bluuebunny/crossref_metadata_2025 huggingface dataset:
On the Representation of the Porosity‐Pressure Relationship in General Subsurface Flow Codes
Authors: Birdsell Daniel T. , Karra Satish , Rajaram Harihar
Published: January 2018

The governing equations for subsurface flow codes in a deformable porous media are derived from the balance of fluid mass and Darcy's equation. One class of these codes, which we call general subsurface flow codes (GSFs), allow for more general constitutive relations for material properties such as porosity, permeability and density. Examples of GSFs include PFLOTRAN, FEHM, TOUGH2, STOMP, and some reservoir simulators such as BOAST. Depending on the constitutive relations used in GSFs, an inconsistency arises between the standard groundwater flow equation and the governing equation of GSFs, and we clarify that the reason for this inconsistency is because the Darcy's equation used in the GSFs should account for the velocity of fluid with respect to solid. Due to lack of awareness of this inconsistency, users of the GSFs tend to use a porosity‐pressure relationship that comes from the standard groundwater flow equation and assumes that the relative velocity is already accounted for. For the Theis problem, we show that using this traditional relationship in the GSFs leads to significantly large errors. We propose an alternate porosity‐pressure relationship that is consistent with the derivation of the governing equations in the GSFs where the solid velocity is not tracked, and show that, with this relationship, the results are more accurate for the Theis problem. The purpose of this note is to make the users and developers of these GSFs aware of this inconsistency and to advocate that the alternate porosity model derived here should be incorporated in GSFs.
Variations in dosimetric distribution and plan complexity with collimator angles in hypofractionated volumetric arc radiotherapy for treating prostate cancer
Authors: Li Ming‐Hsien , Huang Sheng‐Fang , Chang Chih‐Chieh , Lin Jang‐Chun , Tsai Jo‐Ting
Published: January 2018

Purpose

Hypofractionated radiotherapy can reduce treatment durations and produce effects identical to those of conventionally fractionated radiotherapy for treating prostate cancer. Volumetric arc radiotherapy (VMAT) can decrease the treatment machine monitor units (MUs). Previous studies have shown that VMAT with multileaf collimator (MLC) rotation exhibits better target dose distribution. Thus, VMAT with MLC rotation warrants further investigation.

Methods and materials

Ten patients with prostate cancer were included in this study. The prostate gland and seminal vesicle received 68.75 and 55 Gy, respectively, in 25 fractions. A dual‐arc VMAT plan with a collimator angle of 0° was generated and the same constraints were used to reoptimize VMAT plans with different collimator angles. The conformity index (CI), homogeneity index (HI), gradient index (GI), normalized dose contrast (NDC), MU, and modulation complexity score (MCSV) of the target were analyzed. The dose–volume histogram of the adjacent organs was analyzed. A Wilcoxon signed‐rank test was used to compare different collimator angles.

Results

Optimum values of CI, HI, and MCSV were obtained with a collimator angle of 45°. The optimum values of GI, and NDC were observed with a collimator angle of 0°. In the rectum, the highest values of maximum dose and volume receiving 60 Gy (V60 Gy) were obtained with a collimator angle of 0°, and the lowest value of mean dose (Dmean) was obtained with a collimator angle of 45°. In the bladder, high values of Dmean were obtained with collimator angles of 75° and 90°. In the rectum and bladder, the values of V60 Gy obtained with the other tested angles were not significantly higher than those obtained with an angle of 0°.

Conclusion

This study found that MLC rotation affects VMAT plan complexity and dosimetric distribution. A collimator angle of 45° exhibited the optimal values of CI, HI, and MCSv among all the tested collimator angles. Late side effects of the rectum and bladder are associated with high‐dose volumes by previous studies. MLC rotation did not have statistically significantly higher values of V60 Gy in the rectum and bladder than did the 0° angle. We thought a collimator angle of 45° was an optimal angle for the prostate VMAT treatment plan. The findings can serve as a guide for collimator angle selection in prostate hypofractionated VMAT planning.
Optimizing the NIR Fluence Threshold for Nanobubble Generation by Controlled Synthesis of 10–40 nm Hollow Gold Nanoshells
Authors: Ogunyankin Maria O. , Shin Jeong Eun , Lapotko Dmitri O. , Ferry Vivian E. , Zasadzinski Joseph A.
Published: January 2018

The laser fluence to trigger nanobubbles around hollow gold nanoshells (HGN) with near infrared light is examined through systematic modification of HGN size, localized surface plasmon resonance (LSPR), HGN concentration, and surface coverage. Improved temperature control during silver template synthesis provides monodisperse, silver templates as small as 9 nm. 10 nm HGN with <2 nm shell thickness are prepared from these templates with a range of surface plasmon resonances from 600 to 900 nm. The fluence of picosecond near infrared (NIR) pulses to induce transient vapor nanobubbles decreases with HGN size at a fixed LSPR wavelength, unlike solid gold nanoparticles of similar dimensions that require an increased fluence with decreasing size. Nanobubble generation causes the HGN to melt with a blue shift of the LSPR. The nanobubble threshold fluence increases as the irradiation wavelength moves off the nanoshell LSPR. Surface treatment does not influence the threshold fluence. The threshold fluence increases with decreasing HGN concentration, suggesting that light localization through multiple scattering plays a role. The nanobubble threshold to rupture liposomes is four times smaller for 10 nm than for 40 nm HGN at a given LSPR, allowing us to use HGN size, LSPR, laser wavelength and fluence to control nanobubble generation.
Compositionally Graded Absorber for Efficient and Stable Near‐Infrared‐Transparent Perovskite Solar Cells
Authors: Fu Fan , Pisoni Stefano , Weiss Thomas P. , Feurer Thomas , Wäckerlin Aneliia , Fuchs Peter , Nishiwaki Shiro , Zortea Lukas , Tiwari Ayodhya N. , Buecheler Stephan
Published: January 2018

Compositional grading has been widely exploited in highly efficient Cu(In,Ga)Se2, CdTe, GaAs, quantum dot solar cells, and this strategy has the potential to improve the performance of emerging perovskite solar cells. However, realizing and maintaining compositionally graded perovskite absorber from solution processing is challenging. Moreover, the operational stability of graded perovskite solar cells under long‐term heat/light soaking has not been demonstrated. In this study, a facile partial ion‐exchange approach is reported to achieve compositionally graded perovskite absorber layers. Incorporating compositional grading improves charge collection and suppresses interface recombination, enabling to fabricate near‐infrared‐transparent perovskite solar cells with power conversion efficiency of 16.8% in substrate configuration, and demonstrate 22.7% tandem efficiency with 3.3% absolute gain when mechanically stacked on a Cu(In,Ga)Se2 bottom cell. Non‐encapsulated graded perovskite device retains over 93% of its initial efficiency after 1000 h operation at maximum power point at 60 °C under equivalent 1 sun illumination. The results open an avenue in exploring partial ion‐exchange to design graded perovskite solar cells with improved efficiency and stability.
Topotactic Engineering of Ultrathin 2D Nonlayered Nickel Selenides for Full Water Electrolysis
Authors: Wu Hao , Lu Xin , Zheng Gengfeng , Ho Ghim Wei
Published: January 2018

Fabrication of ultrathin 2D nonlayered nanomaterials remains challenging, yet significant due to the new promises in electrochemical functionalities. However, current strategies are largely restricted to intrinsically layered materials. Herein, a combinatorial self‐regulating acid etching and topotactic transformation strategy is developed to unprecedentedly prepare vertically stacked ultrathin 2D nonlayered nickel selenide nanosheets. Due to the inhibited hydrolyzation under acidic conditions, the self‐regulating acid etching results in ultrathin layered nickel hydroxides (two layers). The ultrathin structure allows limited epitaxial extension during selenization, i.e., the nondestructive topotactic transformation, enabling facile artificial engineering of hydroxide foundation frameworks into ultrathin nonlayered selenides. Consequently, the exquisite nonlayered nickel selenide affords high turnover frequencies, electrochemical surface areas, exchange current densities, and low Tafel slopes, as well as facilitating charge transfer toward both oxygen and hydrogen evolution reactions. Thus, the kinetically favorable bifunctional electrocatalyst delivers advanced and robust overall water splitting activities in alkaline intermediates. The integrated methodology may open up a new pathway for designing other highly active 2D nonlayered electrocatalysts.
Skills transfer to sinus surgery via a low‐cost simulation‐based curriculum
Authors: Harbison R. Alex , Dunlap Jennifer , Humphreys Ian M. , Davis Greg E.
Published: January 2018

Background

Surgical skill development outside the operating room aims to improve technique and subsequent patient safety. The purpose of this study was to evaluate the correlation between technical and cognitive skills with cadaveric endoscopic sinus surgery (ESS) performance and change in ESS performance before and after implementation of a dedicated ESS simulation‐based and knowledge‐based curriculum.

Methods

A before‐after study design was implemented among 10 medical students and 10 junior otolaryngology residents. Participants completed a knowledge‐based, multiple‐choice ESS pretest and watched an ESS prosection video. Participants performed 9 tasks on a previously validated low‐cost, low‐technology, nonbiologic sinus surgery task trainer followed by cadaveric maxillary antrostomy and anterior ethmoidectomy. Participants then completed a simulation‐based and knowledge‐based ESS curriculum followed by a repeat cadaveric maxillary antrostomy and anterior ethmoidectomy. Performance was graded with a 5‐point global rating scale (GRS) and a 5‐point ESS‐specific checklist.

Results

We observed a stronger correlation between the multiple‐choice, knowledge‐based, ESS pretest scores and cadaveric ESS GRS score (r = 0.73) than between task trainer performance and cadaveric ESS GRS score (r = 0.43). We also noted a significant increase in precurriculum vs postcurriculum mean ± standard deviation (SD) cadaveric ESS checklist scores for both medical students (1.18 ± 0.25 vs 2.58 ± 0.57; p = 0.0002) and residents (2.09 ± 0.78 vs 2.88 ± 0.54; p = 0.023). The greatest improvements for residents were in performance of uncinectomy, enlargement of maxillary os, and identification of the bulla.

Conclusion

These findings provide evidence supporting the use of ESS training curricula outside the operating room.
Catalytic Desymmetrizing Dehydrogenation of 4‐Substituted Cyclohexanones through Enamine Oxidation
Authors: Zhu Lihui , Zhang Long , Luo Sanzhong
Published: January 2018

A desymmetrizing dehydrogenation process catalyzed by a chiral primary amine is described herein. The reaction proceeds through the oxidation of a ketone enamine by IBX and enables the highly enantioselective desymmetrization of 4‐substituted cyclohexanones with the generation of chiral 4‐substituted cyclohexenones containing a remote γ‐stereocenter.
Kryptofix 5 as an inexpensive and efficient ligand for the palladium‐catalyzed Mizoroki‐Heck reaction
Authors: Movassagh Barahman , Ranjbari Shabnam
Published: January 2018

A novel complex of PdCl2 with a multidentate cryptand ligand, Kryptofix 5, has been prepared and characterized by various techniques including 1H‐ and 13C NMR spectroscopy, Fourier transform infrared (FT‐IR), Raman, ultraviolet and visible (UV‐VIS) spectroscopy, inductively coupled plasma (ICP), CHN elemental and energy dispersive X‐ray analysis (EDX). This heat‐ and air‐stable complex was utilized as a highly active catalyst for the Mizoroki‐Heck reaction of aryl halides with various olefins. Interestingly, it was found that aryl bromides as well as aryl iodides were efficiently cross‐coupled with terminal alkenes at 130 °C in 10 min. Furthermore, the least reactive aryl chlorides reacted with styrene to obtain the desired products in acceptable yields.
Silver nanoparticles supported on ionic‐tagged magnetic hydroxyapatite as a highly efficient and reusable nanocatalyst for hydrogenation of nitroarenes in water
Authors: Pashaei Mokhtar , Mehdipour Ebrahim
Published: January 2018

A novel chemically modified magnetic hydroxyapatite (MHAp) was prepared and used as support and stabilizer for the synthesis of silver nanoparticles. First, 1,4‐diazabicyclo[2.2.2]octane (DABCO) was successfully grafted onto the surface of MHAp, and then silver nanoparticles were homogeneously loaded on mesoporous MHAp‐DABCO (ionic‐tagged MHAp) nanocomposite by in situ chemical reduction of silver nitrate using sodium borohydride. The structure and properties of the resulting MHAp‐DABCO‐Ag nanocomposite were confirmed using various techniques. The catalytic activity of ionic‐tagged MHAp‐Ag nanocatalyst was investigated for the hydrogenation reaction of nitroarenes in aqueous media. The results reveal that the Ag‐containing inorganic–organic nanocomposite is highly efficient for the reduction of a wide range of aromatic nitro compounds under green conditions. The superparamagnetic nature of the nanocatalyst leads to its being readily removed from solution via application of a magnetic field, and it can be easily stored and reused.
Nanostructured Pyrophosphate Na2PdP2O7‐Catalyzed Suzuki‐Miyaura Cross‐Coupling Under Microwave Irradiation
Authors: Dânoun Karim , Essamlali Younes , Amadine Othmane , Tabit Rida , Fihri Aziz , Len Christophe , Zahouily Mohamed
Published: January 2018

Nanostructured palladium pyrophosphate (Na2PdP2O7) catalyst was synthesized and well characterized by using different techniques (TGA, XRD, SEM, TEM....). This nanocatalyst exhibited excellent catalytic activity in the synthesis of biaryl compounds via Suzuki‐Miyaura cross‐coupling to produce their corresponding products in good to excellent yields under mild conditions. The catalyst is recyclable and was recycled for four runs for the reaction of 4‐bromoacetophenone with phenylboronic acid without appreciable loss of its catalytic activity.
Cell‐based studies of the first‐in‐class half‐sandwich Ir(III) complex containing histone deacetylase inhibitor 4‐phenylbutyrate
Authors: Štarha Pavel , Trávníček Zdeněk , Drahoš Bohuslav , Herchel Radovan , Dvořák Zdeněk
Published: January 2018

We report on a cytotoxic half‐sandwich iridium(III) complex [Ir(η5‐Cpph)(phen)(PB)]PF6 (1‐PB), containing a monodentate coordinated O‐donor 4‐phenylbutyrato ligand (PB) belonging to the family of histone deacetylase inhibitors (HDACi); HCpph = (2,3,4,5‐tetramethylcyclopenta‐2,4‐dien‐1‐yl)benzene, phen = 1,​10‐phenanthroline. The solution behaviour studies indicated that complex 1‐PB partially hydrolysed in the mixture of methanol and water (1:4, v/v), resulting in the release of the PB ligand. The extent of the PB ligand release increased in the presence of 2 molar equiv. of the reduced glutathione (GSH). Complex 1‐PB exhibited comparable in vitro cytotoxicity against the cisplatin‐sensitive (IC50 = 15.8 μM) and ‐resistant (IC50 = 13.0 μM) variants of the A2780 human ovarian carcinoma cells, while its potency against the MRC‐5 human normal fibroblast cells was markedly lower (IC50 = 124.1 μM). The cytotoxicity studies revealed an ability of complex 1‐PB to overcome the acquired resistance against cisplatin, with the resistance factor (RF = 0.8) being markedly lower than for complex 1‐Cl (RF = 1.8) and cisplatin (RF = 2.9). The A2780 cell‐based flow cytometry experiments showed different cell cycle modification induced by complex 1‐PB and cisplatin, induction of production of reactive oxygen species, and higher mitochondria membrane potential depleted cell populations after the treatment by complex 1‐PB as compared with cisplatin. In the cell‐free assay, complex 1‐PB inhibited the HDAC activity to ca 66% as compared to ca 74% valid for NaPB. The [Ir(η5‐Cpph)(phen)(H2O)]2+ species (1‐OH2), representing the hydrolysis product of both complexes 1‐PB and 1‐Cl, induced hydroxyl radical from the hydrogen peroxide, as proved by the EPR spin trapping studies with the 5‐(diethoxyphosphoryl)‐5‐methyl‐1‐pyrroline‐N‐oxide (DEPMPO) spin trap.
The colloidal properties of alkaline‐soluble waterborne polymers
Authors: Scheerder Jurgen , Dollekens Remy , Langermans Harm
Published: January 2018

Waterborne polymer dispersions are widely used in coatings and graphic arts markets as environmentally friendly and more sustainable alternatives to solvent borne binders. Traditionally, waterborne (meth)acrylic dispersions are prepared by emulsion polymerization using low molar mass surfactants as a key ingredient to control particle size. However, these surfactants can have a negative influence on the performance of coatings such as reduced water resistance and adhesion. To mitigate the negative effects of surfactants, polymer latexes have been developed that employ alkaline‐soluble polymers as the sole stabilizer for a subsequent emulsion polymerization step. In this way surfactant‐free polymer dispersions are obtained. Despite the high commercial impact and relevance of this technology, fundamental studies regarding the physicochemical properties of the alkaline‐soluble polymers are lacking. In this article, the synthesis and colloidal properties of alkaline‐soluble waterborne methacrylic copolymers are reported. The dissolution behavior and colloidal properties of these alkaline‐soluble polymers were studied as function of molar mass, acid content, and pH. The dissolving polymer particles were characterized using static and dynamic light scattering, static and dynamic surface tension measurements, and cryogenic‐transmission electron microscopy analysis. It is concluded that the dissolution mechanism of alkaline‐soluble polymers follows a gradual process. As the pH increases deprotonation of the carboxylic acid groups swells the particle enhancing the further swelling with water. At a certain amount of base, the particles disintegrate into small polymer aggregates while the most water‐soluble polymer chains are dissolved in the water phase. An important learning is that part of the alkaline‐soluble polymer resides in very small particles (<5 nm). The formation of these polymer particles below 5 nm was not reported previously and offers a new insight into the dissolution mechanism of alkaline soluble polymers. The most important parameter steering this process is the acid value of the polymer, while the molar mass plays a modest role. The understanding gained in this study can be used to further advance alkaline‐soluble polymers as stabilizer in surfactant‐free emulsion polymerization technology, improving the performance of a wide range of industrially relevant coatings. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46168.
Molecular characterization and gene silencing of Laccase 1 in the grain aphid, Sitobion avenae
Authors: Zhang Yong , Fan Jia , Francis Frédéric , Chen Julian
Published: January 2018

Laccase 1 (Lac1), a polyphenol oxidase, has been proposed to be involved in insect iron metabolism and immunity responses. However, little information is available on the roles of Lac 1 in insect–plant interactions. The grain aphid Sitobion avenae is one of the most destructive pests of cereal, directly drawing phloem sap and transmitting viruses. In the present study, we first cloned the open reading frame (ORF) of Lac 1 from S. avenae, and the putative protein sequence was predicted to have a carboxyl‐terminal transmembrane domain. We found that SaLac1 had higher expression levels in the fourth and adult stages using reverse transcription real‐time quantitative PCR (RT‐qPCR). SaLac 1 was highly expressed in the salivary gland and midgut and also in wingless compared with winged morphs. After feeding on aphid‐resistant wheat with a high total phenol content, the expression level of SaLac 1 increased significantly. RNA interference (RNAi) by oral feeding successfully inhibited the transcript levels of SaLac 1, and the knockdown of Lac 1 significantly decreased the survival rate of S. avenae on aphid‐resistant wheat. Our study demonstrated that S. avenae Lac1 was involved in the detoxification of phenolic compounds in wheat and was essential for the aphid to adapt to resistant plants.
Maternal exposures and risk of oral clefts in South Vietnam
Authors: Dien Vu H. A. , McKinney Christy M. , Pisek Araya , Pitiphat Waranuch
Published: January 2018

Background

Oral clefts are among the most common congenital anomalies. Most studies on risk factors of oral clefts have been carried out in developed countries. We investigated the associations between maternal exposures in the first trimester and oral clefts in South Vietnam.

Methods

We conducted a hospital‐based case‐control study during October 2014‐November 2015. Cases included 170 patients with nonsyndromic cleft lip with or without cleft palate and those with cleft palate only. Controls were 170 children without oral clefts, matched to each case by age and gender. Mothers were interviewed using structured questionnaire. We performed conditional logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Passive smoking was associated with increased risk of oral clefts in univariate analysis, but not in multivariable analysis (adjusted OR [aOR] = 1.68; 95% CI, 0.53–5.37). No association was observed between liver intake and oral clefts. Compared with nondrinkers, mothers who reported consumption of caffeine‐containing beverages were more likely to have an infant with oral cleft (aOR = 5.89; 95% CI, 1.08–32.00). Periconceptional use of folic acid and multivitamins supplementation was associated with reduced risk of oral clefts (aOR = 0.01; 95% CI, 0.00–0.09 and aOR = 0.03; 95% CI, 0.01–0.13, respectively).

Conclusions

The results suggest no associations of maternal passive smoking or liver intake with oral clefts. Periconceptional use of folic acid or multivitamins may protect against oral clefts. Further studies are warranted to examine the roles of caffeine consumption in pregnant mothers on occurrence of oral clefts in offspring.
Oral delivery system enhanced the bioavailability of stilbenes: Resveratrol and pterostilbene
Authors: Peng Ru‐Min , Lin Guan‐Ru , Ting Yuwen , Hu Jing‐Yu
Published: January 2018

Stilbenes are a large group of compounds with the C6C2C6 skeleton, in which two aromatic rings are connected by an ethylene bridge. Resveratrol and its structural analog, pterostilbene, are by far the two most widely researched stilbenes in terms of their beneficial bioactivities. However, the bioefficacy of these compounds is greatly reduced when consumed orally due to their poor aqueous solubility, which leads to poor bioavailability. To overcome the limitation, strategies improving their solubility, absorption, and systemic concentration were applied when designing a suitable edible delivery system. This review will summarize the findings from the studies evaluating the oral bioavailability of stilbenes with emphasize on the resveratrol and pterostilbene. It will also include the edible delivery systems currently available and their effect on the oral bioavailability. © 2018 BioFactors, 44(1):5–15, 2018
3D Printing for Chemical Process Laboratories I: Materials and Connection Principles
Authors: Gelhausen Marius Gerrit , Feuerbach Tim , Schubert Ansgar , Agar David William
Published: January 2018

The fabrication of milliliter‐scale test structures for chemical process laboratories with a low‐cost 3D printer operating according to the principle of fused filament fabrication is evaluated. Different polymers such as polypropylene and poly(vinylidene fluoride) were used and fabrication guidelines are provided. Furthermore, reversible and irreversible concepts for connecting 3D‐printed parts to peripherals or to other additively manufactured parts are described. After fabrication, the structures were tested for gas tightness, which was limited without subsequent finishing due to the layer‐wise fabrication process. However, gas tightness up to 600 kPa was attained by using tools like sealing tape. Finally, the developed concepts were extended to permit the insertion of thermoelements or other metallic probes.
Pentacene Dimers as a Critical Tool for the Investigation of Intramolecular Singlet Fission
Authors: Hetzer Constantin , Guldi Dirk M. , Tykwinski Rik R.
Published: January 2018

Singlet fission (SF) involves the spontaneous splitting of a photoexcited singlet state into a pair of triplets, and it holds great promise toward the realization of more efficient solar cells. Although the process of SF has been known since the 1960s, debate regarding the underlying mechanism continues to this day, especially for molecular materials. A number of different chromophores have been synthesized and studied in order to better understand the process of SF. These previous reports have established that pentacene and its derivatives are especially well‐suited for the study of SF, since the energetic requirement E(S1)≥2E(T1) is fulfilled rendering the process exothermic and unidirectional. Dimeric pentacene derivatives, in which individual pentacene chromophores are tethered by a “spacer”, have emerged as the system of choice toward exploring the mechanism of intramolecular singlet fission (iSF). The dimeric structure, and in particular the spacer, allows for controlling and tuning the distance, geometric relationship, and electronic coupling between the two pentacene moieties. This Minireview describes recent advances using pentacene dimers for the investigation of iSF.
Energy Transfer in Supramolecular Heteronuclear Lanthanide Dimers and Application to Fluoride Sensing in Water
Authors: Nonat Aline , Liu Tao , Jeannin Olivier , Camerel Franck , Charbonnière Loïc J.
Published: January 2018

In the presence of fluoride anions, [LnL(H2O)]+ complexes, based on the coordination of a lanthanide (Ln) cation into the cavity of a C2v symmetrical cyclen‐based ligand (L), self‐assemble in water to form [(LnL)2F]+ dimers. The crystal structures of the Yb hydrated monomer and of the fluorinated dimer are reported and analyzed to unravel the impact of the cumulative effect of weak hydrogen bonding and aromatic stacking interactions in the supramolecular assembly. The assembly is stable over a broad range of pH 3–8. A combination of equimolar amounts of Eu and Tb complexes led to a quasistatistical mixture of homo‐ and heterodimers, as observed by using electrospray mass spectrometry. In the heterodimers, selective excitation into the 7F6→5D4 absorption band of the Tb center at λ=488 nm allowed the observation of a Tb‐to‐Eu downshifting energy transfer, not observed in the absence of fluoride ions. Analysis of the excited‐state lifetimes of the dimers within the frame of the Förster theory of energy transfer showed the transfer to have an efficiency of 34 %, with a corresponding Förster radius of 4.1 Å; thereby, unraveling the short Ln–Ln distance as a crucial parameter of the energy‐transfer process. By using equimolar mixtures of the Tb and Eu complexes, the energy‐transfer phenomenon was used for a ratiometric sensing of fluoride anions in water with a detection limit of 17.7 nm.
A “Signal On” Photoelectrochemical Biosensor Based on Bismuth@N,O‐Codoped‐Carbon Core–Shell Nanohybrids for Ultrasensitive Detection of Telomerase in HeLa Cells
Authors: Liu Shanshan , Zhao Shulin , Tu Wenwen , Wang Xiaoying , Wang Xiao , Bao Jianchun , Wang Yu , Han Min , Dai Zhihui
Published: January 2018

Invited for the cover of this issue is the group of Min Han and Zhihui Dai at the Nanjing Normal University. Read the full text of the article at 10.1002/chem.201704251.
Damit die RNA‐Polymerase nicht „fremdgeht“
Authors: Tetsch Larissa
Published: January 2018

DNA‐Methylierungen sind die wichtigste epigenetische Modifikation. Im Promotor sorgen sie dafür, dass das entsprechende Gen still gelegt wird. Innerhalb des in Boten‐RNA umgeschriebenen Genkörpers war ihre Rolle dagegen bislang unklar. Nun wurde gezeigt, dass Methylierungen im Genkörper ebenso wie solche im Promotor eine Anlagerung der RNA‐Polymerase verhindern. Wäre dies nicht der Fall, könnten verkürzte Transkripte und funktionslose Proteine entstehen, die die Zelle schädigen.
In Silico Studies Designed to Select Sesquiterpene Lactones with Potential Antichagasic Activity from an In‐House Asteraceae Database
Authors: Acevedo Chonny Herrera , Scotti Luciana , Scotti Marcus Tullius
Published: January 2018

Chagas disease is an endemic disease caused by Trypanosoma cruzi, which affects more than eight million people, mostly in the Americas. A search for new treatments is necessary to control and eliminate this disease. Sesquiterpene lactones (SLs) are an interesting group of secondary metabolites characteristic of the Asteraceae family that have presented a wide range of biological activities. From the ChEMBL database, we selected a diverse set of 4452, 1635, and 1322 structures with tested activity against the three T. cruzi parasitic forms: amastigote, trypomastigote, and epimastigote, respectively, to create random forest (RF) models with an accuracy of greater than 74 % for cross‐validation and test sets. Afterward, a ligand‐based virtual screen of the entire SLs of the Asteraceae database stored in SistematX (1306 structures) was performed. In addition, a structure‐based virtual screen was also performed for the same set of SLs using molecular docking. Finally, using an approach combining ligand‐based and structure‐based virtual screening along with the equations proposed in this study to normalize the probability scores, we verified potentially active compounds and established a possible mechanism of action.
A comprehensive analysis of neurotrophins and neurotrophin tyrosine kinase receptors expression during development of zebrafish
Authors: Nittoli Valeria , Sepe Rosa M. , Coppola Ugo , D'Agostino Ylenia , De Felice Elena , Palladino Antonio , Vassalli Quirino A. , Locascio Annamaria , Ristoratore Filomena , Spagnuolo Antonietta , D'Aniello Salvatore , Sordino Paolo
Published: January 2018

Neurotrophins (NTF) are a family of secreted nerve growth factors with affinity for tyrosine kinase (Ntrk) and p75 receptors. To fully understand the variety of developmental roles played by NTFs, it is critical to know when and where genes encoding individual ligands and receptors are transcribed. Identification of ntf and ntrk transcripts in zebrafish development remains to be fully characterized for further uncovering the potential function(s) of the NTF signal transduction pathway. Here, we conducted a systematic analysis of the expression profiles of four ntf and five ntrk genes during zebrafish development using whole‐mount in situ hybridization. Our study unveils new expression domains in the developing embryo, confirms those previously known, and shows that ntf and ntrk genes have different degrees of cell‐ and tissue‐type specificity. The unique and overlapping expression patterns here depicted indicate the coordination of the redundant and divergent functions of NTFs and represent valuable tools for deciphering the molecular pathways involved in the specification and function of embryonic cell types.
Eye‐specific segregation and differential fasciculation of developing retinal ganglion cell axons in the mouse visual pathway
Authors: Sitko Austen A. , Kuwajima Takaaki , Mason Carol A.
Published: January 2018

Prior to forming and refining synaptic connections, axons of projection neurons navigate long distances to their targets. While much is known about guidance cues for axon navigation through intermediate choice points, whether and how axons are organized within tracts is less clear. Here we analyze the organization of retinal ganglion cell (RGC) axons in the developing mouse retinogeniculate pathway. RGC axons are organized by both eye‐specificity and topography in the optic nerve and tract: ipsilateral RGC axons are segregated from contralateral axons and are offset laterally in the tract relative to contralateral axon topographic position. To identify potential cell‐autonomous factors contributing to the segregation of ipsilateral and contralateral RGC axons in the visual pathway, we assessed their fasciculation behavior in a retinal explant assay. Ipsilateral RGC neurites self‐fasciculate more than contralateral neurites in vitro and maintain this difference in the presence of extrinsic chiasm cues. To further probe the role of axon self‐association in circuit formation in vivo, we examined RGC axon organization and fasciculation in an EphB1−/− mutant, in which a subset of ipsilateral RGC axons aberrantly crosses the midline but targets the ipsilateral zone in the dorsal lateral geniculate nucleus on the opposite side. Aberrantly crossing axons retain their association with ipsilateral axons in the contralateral tract, indicating that cohort‐specific axon affinity is maintained independently of guidance signals present at the midline. Our results provide a comprehensive assessment of RGC axon organization in the retinogeniculate pathway and suggest that axon self‐association contributes to pre‐target axon organization.
Cognitive Characterization of Air‐Flow Stimulus
Authors: TAKAHASHI HARUKA , BANDO SHIZUKA , OIWA KOSUKE , NOZAWA AKIO , ISHIKAWA TOMOHARU , MITSUI MINORU
Published: January 2018

Extra‐high‐quality audio devices, which are reproducible sound of broadband, have appeared in recent years. Such audio devices of broadband can feel like a deeper sense of realism as an air field by feeling the vibration of the air with entire body. This technology is expected application as sense of presentation technology. Using this technology, development of the new stimulus medium that is the field generating device, such as wrapped up in air is enabled. The purpose of this study is to create a completely new sense with the airflow stimulus termed “air sensation” by using the air field. In this study, we measured the psychophysical quantities to clarify the cognitive characterization of air sensation as a basic examination. Specifically, we measured the absolute thresholds to detect the air‐flow stimulus and sensitivity characteristics with respect to the strength of the stimulus. Consequently, it was revealed that cognitive characterizations vary with the properties of signal waveform, stimulus presentation site, and stimulus presentation order.
Electrochemical Aptasensor Based on Poly(Neutral Red) and Carboxylated Pillar[5]arene for Sensitive Determination of Aflatoxin M1
Authors: Smolko Vladimir , Shurpik Dmitry , Porfireva Anna , Evtugyn Gennady , Stoikov Ivan , Hianik Tibor
Published: January 2018

Aptasensor for highly sensitive determination of aflatoxin M1 (AFM1) was developed on the base of glassy carbon electrode (GCE) covered with polymeric Neutral red (NR) dye obtained by electropolymerization in the presence of polycarboxylated pillar[5]arene derivative. Aptamer against AFM1 and NR label were then covalently linked to the carboxylic groups of the carrier by carbodiimide binding. At presence of AFM1 the cathodic peak current related to the NR conversion decreases. AFM1 induced also an increase of the charge transfer resistance measured by electrochemical impedance spectroscopy. In optimal conditions, this make it possible to determine from 5 to 120 ng/L AFM1 in standard solutions with limit of detection (LOD) of 0.5 ng/L. The aptasensor was validated on the spiked samples of cow and sheep milk as well as in kefir after their methanol dilution. Reliable detection of the 40–160 ng/kg of mycotoxins was reached. This is below limited threshold value (50 μg/kg) established in EC.
WT1 peptide‐based immunotherapy for advanced thymic epithelial malignancies
Authors: Oji Yusuke , Inoue Masayoshi , Takeda Yoshito , Hosen Naoki , Shintani Yasushi , Kawakami Manabu , Harada Takuya , Murakami Yui , Iwai Miki , Fukuda Mari , Nishida Sumiyuki , Nakata Jun , Nakae Yoshiki , Takashima Satoshi , Shirakata Toshiaki , Nakajima Hiroko , Hasegawa Kana , Kida Hiroshi , Kijima Takashi , Morimoto Soyoko , Fujiki Fumihiro , Tsuboi Akihiro , Morii Eiichi , Morita Satoshi , Sakamoto Junichi , Kumanogoh Atsushi , Oka Yoshihiro , Okumura Meinoshin , Sugiyama Haruo
Published: January 2018

Thymic epithelial tumors are rare malignancies, and no optimal therapeutic regimen has been defined for patients with advanced disease. Patients with advanced thymic epithelial tumors, which were resistant or intolerable to prior therapies, were eligible for this study. Patients received 9 mer‐WT1‐derived peptide emulsified with Montanide ISA51 adjuvant via intradermal administration once a week as a monotherapy. After the 3‐month‐protocol treatment, the treatment was continued mostly at intervals of 2–4 weeks until disease progression or intolerable adverse events occurred. Of the 15 patients enrolled, 11 had thymic carcinoma (TC) and 4 had invasive thymoma (IT). Median period from diagnosis to the start of treatment was 13.3 and 65.5 months for TC and IT, respectively. No patients achieved a complete or partial response. Of the 8 evaluable TC patients, 6 (75.0%) had stable disease (SD) and 2 had progressive disease (PD). Of the 4 evaluable IT patients, 3 (75.0%) had SD and 1 (25.0%) had PD. Median period of monotherapy treatment was 133 and 683 days in TC and IT patients, respectively. No severe adverse events occurred during the 3‐month‐protocol treatment. As adverse events in long responders, thymoma‐related autoimmune complications, pure red cell aplasia and myasthenia gravis occurred in two IT patients. Cerebellar hemorrhage developed in a TC patient complicated with Von Willebrand disease. Induction of WT1‐specific immune responses was observed in the majority of the patients. WT1 peptide vaccine immunotherapy may have antitumor potential against thymic malignancies.
A generalized focused information criterion for GMM
Authors: Chang Minsu , DiTraglia Francis J.
Published: January 2018

This paper proposes a criterion for simultaneous generalized method of moments model and moment selection: the generalized focused information criterion (GFIC). Rather than attempting to identify the “true” specification, the GFIC chooses from a set of potentially misspecified moment conditions and parameter restrictions to minimize the mean squared error (MSE) of a user‐specified target parameter. The intent of the GFIC is to formalize a situation common in applied practice. An applied researcher begins with a set of fairly weak “baseline” assumptions, assumed to be correct, and must decide whether to impose any of a number of stronger, more controversial “suspect” assumptions that yield parameter restrictions, additional moment conditions, or both. Provided that the baseline assumptions identify the model, we show how to construct an asymptotically unbiased estimator of the asymptotic MSE to select over these suspect assumptions: the GFIC. We go on to provide results for postselection inference and model averaging that can be applied both to the GFIC and various alternative selection criteria. To illustrate how our criterion can be used in practice, we specialize the GFIC to the problem of selecting over exogeneity assumptions and lag lengths in a dynamic panel model, and show that it performs well in simulations. We conclude by applying the GFIC to a dynamic panel data model for the price elasticity of cigarette demand.
Realized extreme quantile: A joint model for conditional quantiles and measures of volatility with EVT refinements
Authors: Bee Marco , Dupuis Debbie J. , Trapin Luca
Published: January 2018

We propose a new framework exploiting realized measures of volatility to estimate and forecast extreme quantiles. Our realized extreme quantile (REQ) combines quantile regression with extreme value theory and uses a measurement equation that relates the realized measure to the latent conditional quantile. Model estimation is performed by quasi maximum likelihood, and a simulation experiment validates this estimator in finite samples. An extensive empirical analysis shows that high‐frequency measures are particularly informative of the dynamic quantiles. Finally, an out‐of‐sample forecast analysis of quantile‐based risk measures confirms the merit of the REQ.
MAPK and NF‐κB signalling pathways regulate the expression of miRNA, let‐7f in human endocervical epithelial cells
Authors: Ayyar Kanchana K. , Reddy Kudumula V. R.
Published: January 2018

MicroRNAs (miRNAs) mediate post‐transcriptional gene suppression and are a critical component of the complex regulatory networks in epithelial immune responses. Transcription of miRNA genes in epithelial cells can be elaborately controlled through Toll‐like receptors (TLRs), and associated nuclear factor kappa‐light‐chain‐enhancer of activated B cells (NF‐κB) and mitogen‐activated protein kinase (MAPK) pathways, leading to nuclear transcription factor associated‐transactivation and transrepression of miRNAs. MiRNA, let‐7f is involved in the regulation of innate immune responses post TLR3 stimulation in human endocervical cells (End1/E6E7) and decreased let‐7f is associated with poor immune activation. Thus, expression of let‐7f is under strict control. However, the mechanism by which let‐7f is regulated in these cells is not known. Therefore, in the present study, we have investigated the role of MAPK and NF‐κB in the transcription of let‐7f. We report that signalling of TLR3, results in activation of multiple signalling pathways including MAPK/ERK, JNK, p38, and NF‐κB. Of these MAPK/ p38 and JNK directly influence the expression of let‐7f in End1/E6E7 cells. Inhibition of ERK and NF‐κB up regulates the expression of let‐7f and its transcription factor, C/EBPβ. In conclusion, we have identified a system through which TLR3 mediated immune response is regulated by C/EBPβ and let‐7f through the temporal activation of MAPK and NF‐κB in human endocervical cells.
How are the charge transfer descriptors affected by the quality of the underpinning electronic density?
Authors: Maschietto Federica , Campetella Marco , Frisch Michael J. , Scalmani Giovanni , Adamo Carlo , Ciofini Ilaria
Published: January 2018

With the aim of investigating qualitatively and quantitatively the impact of using excited state relaxed or unrelaxed density for the estimation of nature and characteristic of electronic excited states, we analyzed the behavior of 52 exchange correlation functionals for the prediction of density‐based indexes such as those recently introduced in literature to evaluate the charge transfer distance (DCT) (Le Bahers et al. J. Chem. Theory Comput. 2011, 7, 2498) in the case of a prototype family of push–pull dyes. Our results show that while a qualitatively consistent assessment of the nature of the excited states is obtained using either the unrelaxed or the relaxed density, from a quantitative standpoint we observe large discrepancies in the charge transfer distance for electronic transitions having substantial CT character. This behavior is independent of nature of the exchange–correlation functional used. © 2018 Wiley Periodicals, Inc.
Discrimination, religious and cultural factors, and Middle Eastern/Arab Americans’ psychological distress
Authors: Ikizler Ayse S. , Szymanski Dawn M.
Published: January 2018

Objective(s)

We investigated (1) the moderating role of religiosity in the link between religious affiliation and ethnic discrimination and (2) the moderating roles of religiosity, ethnic identity, and family connectedness in the relations between ethnic discrimination and psychological distress.

Method

Our sample consisted of 122 (60% women, 40% men) Middle Eastern/Arab Americans (MEAAs), ranging in age from 18 to 82 years old, who completed an online survey.

Results

Muslim identification predicted discrimination for MEAAs with high but not low religiosity. Higher levels of discrimination, more family connectedness, the interaction of discrimination and religiosity, and the interaction of discrimination and family connectedness were unique predictors of psychological distress.

Conclusions

Religiosity is a risk factor for experiencing ethnic discrimination among Muslim identified MEAAs. MEAAs who have high religiosity and low to moderate levels of family connectedness are vulnerable to psychological distress associated with ethnic discrimination.
Ox‐LDL induces endothelial cell apoptosis and macrophage migration by regulating caveolin‐1 phosphorylation
Authors: Lin Fei , Pei Likai , Zhang Qingbin , Han Weizhong , Jiang Shiliang , Lin Yanliang , Dong Bo , Cui Lianqun , Li Min
Published: January 2018

Oxidative low‐density lipoprotein (ox‐LDL) is a risk factor for atherosclerosis. Ox‐LDL leads to endothelial injury in the initial stage of atherosclerosis. In this study, we investigated the role of ox‐LDL in endothelial injury and macrophage recruitment. We demonstrated that ox‐LDL promoted a dose‐dependent phosphorylation of caveolin‐1 in human umbilical vein endothelial cells. Phosphorylated caveolin‐1 increased ox‐LDL uptake. Intracellular accumulation of ox‐LDL induced NF‐κB p65 phosphorylation, promoted HMGB1 translocation from nucleus to cytoplasm and cytochrome C release from mitochondria to cytoplasm, and activated caspase 3, resulting in cell apoptosis. NF‐κB activation also facilitated cavolin‐1 phosphorylation and HMGB1 expression. In addition, caveolin‐1 phosphorylation favored HMGB1 release and nuclear translocation of EGR1. Nuclear translocation of EGR1 contributed to cytoplasmic translocation of HMGB1. The extracellular HMGB1 induced the migration of PMBC‐derived macrophages toward HUVECs in a TLR4‐dependent manner. Our results suggested that ox‐LDL promoted HUVECs apoptosis and macrophage recruitment by regulating caveolin‐1 phosphorylation.
Haplo‐insufficiency of Bcl2‐associated athanogene 3 in mice results in progressive left ventricular dysfunction, β‐adrenergic insensitivity, and increased apoptosis
Authors: Myers Valerie D. , Tomar Dhanendra , Madesh Muniswamy , Wang JuFang , Song Jianliang , Zhang Xue‐Qian , Gupta Manish K. , Tahrir Farzaneh G. , Gordon Jennifer , McClung Joseph M. , Kontos Christopher D. , Khalili Kamel , Cheung Joseph Y. , Feldman Arthur M.
Published: January 2018

Bcl2‐associated athanogene 3 (BAG3) is a 575 amino acid protein that is found predominantly in the heart, skeletal muscle, and many cancers. Deletions and truncations in BAG3 that result in haplo‐insufficiency have been associated with the development of dilated cardiomyopathy. To study the cellular and molecular events attributable to BAG3 haplo‐insufficiency we generated a mouse in which one allele of BAG3 was flanked by loxP recombination sites (BAG3fl/+). Mice were crossed with α‐MHC‐Cre mice in order to generate mice with cardiac‐specific haplo‐insufficiency (cBAG3+/−) and underwent bi–weekly echocardiography to assess their cardiac phenotype. By 10 weeks of age, cBAG3+/− mice demonstrated increased heart size and diminished left ventricular ejection fraction when compared with non‐transgenic littermates (Cre−/−BAG3fl/+). Contractility in adult myocytes isolated from cBAG3+/− mice were similar to those isolated from control mice at baseline, but showed a significantly decreased response to adrenergic stimulation. Intracellular calcium ([Ca2+]i) transient amplitudes in myocytes isolated from cBAG3+/− mice were also similar to myocytes isolated from control mice at baseline but were significantly lower than myocytes from control mice in their response to isoproterenol. BAG3 haplo‐insufficiency was also associated with decreased autophagy flux and increased apoptosis. Taken together, these results suggest that mice in which BAG3 has been deleted from a single allele provide a model that mirrors the biology seen in patients with heart failure and BAG3 haplo‐insufficiency.