bluuebunny/crossref_metadata_2025 huggingface dataset:
Bright AIE Nanoparticles with F127 Encapsulation for Deep‐Tissue Three‐Photon Intravital Brain Angiography
Authors: Wang Yalun , Han Xiao , Xi Wang , Li Jinyu , Roe Anna Wang , Lu Ping , Qian Jun
Published: August 2017

Deep‐tissue imaging is of great significance to biological applications. In this paper, a deep‐red emissive luminogen 2,3‐bis(4′‐(diphenylamino)‐[1,1′‐biphenyl]‐4‐yl) fumaronitrile (TPATCN) with aggregation‐induced emission (AIE) feature is prepared. TPATCN molecules were then encapsulated within a polymeric matrix of Pluronic F‐127 to form nanoparticles (NPs). TPATCN NPs exhibit bright three‐photon fluorescence (3PF) in deep‐red region, together with high chemical stability, good photostability, and biocompatibility. They are further utilized for in vivo 3PF imaging of the brain vasculature of mice, under the excitation of a 1550 nm femtosecond laser. A vivid 3D reconstruction of the brain vasculature is then built with a penetration depth of 875 µm, which is the largest in ever reported 3PF imaging based on AIE NPs. After that, by collecting both of the 3PF and third‐harmonic generation signals, multichannel nonlinear optical imaging of the brain blood vessels is further realized. These results will be helpful to study the structures and functions of the brain in the future.
Thiol–Ene Click Reaction as a Facile and General Approach for Surface Functionalization of Colloidal Nanocrystals
Authors: Liu Bin , Deng Xiaoran , Xie Zhongxi , Cheng Ziyong , Yang Piaoping , Lin Jun
Published: August 2017

Oleic acid (OA) and/or oleylamine (OAm) are generally used as the surface ligands for stabilization of inorganic nanocrystals (NCs). The hydrophobic and inert surface of the NCs limits their applications such as in biomedical areas. Hence, surface modifications are essential in many physical and chemical processes. Here, a facile and versatile strategy is reported for the modification of NCs by ultraviolet‐induced thiol–ene chemistry, in which thiol‐terminated poly(ethylene glycol) (HSPEG) and its derivatives can react directly with double bonds in OA/OAm ligands to form covalent linking within one step. Through this strategy, various hydrophobic NCs with different compositions and morphologies are able to be transferred into water combining with functionalization of active groups. As a proof‐of‐concept, this strategy is successfully used to construct a sensor for detecting avidin based on upconverting luminescence analysis. Therefore, this strategy provides a new tool for designing and tuning the surface properties of NCs for different applications.
The Synthesis of Chiral α‐Aryl α‐Hydroxy Carboxylic Acids via RuPHOX‐Ru Catalyzed Asymmetric Hydrogenation
Authors: Guo Huan , Li Jing , Liu Delong , Zhang Wanbin
Published: August 2017

A ruthenocenyl phosphino‐oxazoline‐ruthenium complex (RuPHOX−Ru) catalyzed asymmetric hydrogenation of α‐aryl keto acids has been successfully developed, affording the corresponding chiral α‐aryl α‐hydroxy carboxylic acids in high yields and with up to 97% ee. The reaction could be performed on a gram scale with a relatively low catalyst loading (up to 5000 S/C) and the resulting products can be transformed to several chiral building blocks, biologically active compounds and chiral drugs.

magnified image
Synthesis of Fluorinated Benzo[a]quinolizidines via Visible Light‐induced Tandem Substitution of Two Fluorine Atoms in a CF3 Group
Authors: Chen Haoguo , Xiao Tiebo , Li Linyong , Anand Devireddy , He Yuwei , Zhou Lei
Published: August 2017

An efficient method for the construction of fluorinated benzo[a]quinolizidines from α‐trifluoromethyl alkenes and dihydroisoquinoline acetic acids using visible light photocatalysis was developed. The reaction was accomplished through a decarboxylative/defluorinative cross‐coupling, followed by an intramolecular defluorinative C−H functionalization in one‐pot. Diversified fluorinated benzo[a]quinolizidines, which are less accessible by other methods, were obtained in good yields with high diastereoselectivity.

magnified image
Gustatory and olfactory responses to stimulation of the human insula
Authors: Mazzola Laure , Royet Jean‐Pierre , Catenoix Hélène , Montavont Alexandra , Isnard Jean , Mauguière François
Published: August 2017

Objective

Despite numerous studies suggesting the role of insular cortex in the processing of gustatory and olfactory inputs, the exact location of olfactogustatory representation in the insula remains controversial. Here we provide a functional mapping of olfactory–gustatory responses to stimulation of the human insular cortex.

Methods

We reviewed 651 electrical stimulations of the insula that were performed in 221 patients, using stereotactically implanted depth electrodes, during the presurgical evaluation of drug‐refractory epilepsy.

Results

Gustatory sensations were evoked in 15 (2.7%) of the 550 stimulations that elicited a clinical response. They were exclusively obtained after stimulation of a relatively delimited zone of insula, located in its mid‐dorsal part (posterior short gyrus). Six olfactory sensations (1.1%) could be obtained during stimulations of an insular region that partially overlapped with the gustatory representation.

Interpretation

Our study provides a functional mapping of gustatory representation in the insular posterior short gyrus and the first detailed description of olfactory sensations obtained by direct stimulation of mid‐dorsal insula. Our data also show a spatial overlap between gustatory, olfactory, and oral somatosensory representation in the mid‐dorsal insula, and suggest that this part of the insula may be an integrated oral sensory region that plays a key role in flavor perception. It also indicates that dysfunction in this region should be considered during the evaluation of gustatory and olfactory epileptic seizures. Ann Neurol 2017;82:360–370
Synthesis and thermal properties of organically modified palygorskite/fluorinated polyurethane nanocomposites
Authors: Li Ying , Zhu Zhiqiang , Wang Xia
Published: August 2017

In this article, fluorinated polyurethane (FPU) nanocomposites filled with organic modified palygorskite (Pal) were synthesized and characterized by Fourier transform infrared, X‐ray diffraction, thermogravimetric analysis (TGA), and scanning electron microscope individually. The Pal nanorods were modified with 4,4′‐methylene (MDI) by chemical bond. TGA results showed that there are almost 27 wt % of 4,4′‐methylene grafting or absorbing on Pal nanorods’ surface. Compared with neat FPU, FPU nanocomposites exhibited somewhat increase in the soft segment glass transition temperature and decrease in the hard segment glass transition temperature. It means the compatibility between soft segment and hard segment becomes better than neat FPU. TGA results also showed that the thermal stability of FPU nanocomposites improved with increasing modified Pal loadings. Pal showed good compatibility with the FPU matrix through scanning electron microscope test results. And, the introduction of Pal into FPU matrix will not affect migration of fluoride side chain. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45460.
Biocomposites based on poly(lactic acid) and superabsorbent sodium polyacrylate
Authors: Sartore Luciana , Pandini Stefano , Baldi Francesco , Bignotti Fabio , Di Landro Luca
Published: August 2017

In this research work, biocomposites based on crosslinked particles of sodium polyacrylate, commonly used as superabsorbent polymer, and poly(l‐lactic acid) (PLLA) were developed to obtain superabsorbent thermoplastic products, and to elucidate the role of this type of filler (i.e., polymeric crosslinked particles) on their overall physical‐mechanical behavior. Samples prepared by melt‐blending components with different ratios showed a biphasic system with a uniform distribution of particles, with diameters up to about 50 μm, within the PLLA polymeric matrix. The polymeric biphasic system, coded PLASA, that is, superabsorbent PLLA, showed excellent swelling properties, demonstrating that crosslinked particles retain their superabsorbent ability even if distributed in a thermoplastic polymeric matrix. The thermal characteristics of the biocomposites evidenced enhanced thermal stability in comparison with neat PLLA and also mechanical properties are markedly modified by addition of crosslinked particles, revealing a regular stiffening effect. Furthermore, in aqueous environments the particles swell and are leached from PLLA matrix generating very high porosity. These new open‐pore foams coded PLASAW, that is, PLASA after water treatment, produced in absence of organic solvents and chemical foaming agents, with good physicomechanical properties appear very promising for several applications, for instance in tissue engineering for scaffold production. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45655.
ROMP‐based boron nitride composites
Authors: Hüner Keziban , Ulutaş Kemal , Deligöz Hüseyin , Sartinska Lina , Eren Tarik
Published: August 2017

The present work focuses on the investigation of the thermal and dielectric properties of composites obtained by surface‐modified hexagonal boron nitride (hBN) and ring‐opening metathesis polymerization (ROMP) based polymer. A new kind of high performance composites was developed based on using amino silane functionalized hBN (AS‐hBN) and bromine functional group possessing homo and copolymers synthesized via ROMP pathway. Aminosilane capped boron nitride (BN) and bromine bearing polymer backbone enhance the interaction between filler and the polymer chains. The effects of surface‐modified BN (AS‐hBN) and its content on the dielectric properties, and thermal resistance of composites, are systematically investigated and discussed. The resultant composites possess high electrical break over voltages. While all of the ROMP‐based films exhibit low ɛ′ value in a wide frequency range, in the case of the composite with 20% AS‐hBN and poly(bromooxanorbornene‐co‐cyclooctadiene) (ROMP‐BN‐6) displays very low dielectric constants in around 1.5 up to 1 MHz at 20 °C. This value is significantly lower than that of common polymer dielectrics, which is usually in the range of 3–6. Besides the lowest dielectric constant of ROMP‐BN‐6, it has also the smallest dielectric loss tangent even at high temperatures. Tan δ of ROMP‐BN‐6 is 0.003 and 0.0067 at 10 Hz–1 MHz at 20 °C, respectively. Thermal stability of polymers was also improved by introducing surface‐modified hBN. Polymers bearing 20% AS‐hBN are highly thermally stable up to ∼350 °C and gave 25% char yield at 800 °C. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45658.
Effect of chemically modified clinoptilolite on the thermal, morphological, and gas separation properties of mixed matrix membranes
Authors: Castruita‐de León Griselda , Meléndez‐Ortiz H. Iván , Hernández‐Silva Gema C. , García‐Rodríguez Sandra P. , García‐Cerda Luis Alfonso , Montes‐Luna Angel de J.
Published: August 2017

Mixed matrix membranes (MMM) based on polysulfone and chemically modified clinoptilolite were prepared. Clinoptilolite enriched with Ca2+, K+, and Na+ by ion exchange at two test temperatures was prepared. Chemical composition was monitored by energy dispersive X‐ray spectroscopy. X‐ray diffraction, thermogravimetric analysis, and N2 adsorption–desorption isotherms were also performed. Thermal and morphological properties of MMM were evaluated. CH4/CO2 gas mixture permeability tests at different upstream pressure were carried out. Type of exchanged cation in modified clinoptilolite affected the CO2 permeability. An improvement on the CO2/CH4 selectivity values in the MMM compared to the polymeric membrane was appreciated. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45659.
Geographic variation in host fish use and larval metamorphosis for the endangered dwarf wedgemussel
Authors: St. John White Barbara , Paola Ferreri C. , Lellis William A. , Wicklow Barry J. , Cole Jeffrey C.
Published: August 2017

Host fishes play a crucial role in survival and dispersal of freshwater mussels (Unionoida), particularly rare unionids at conservation risk. Intraspecific variation in host use is not well understood for many mussels, including the endangered dwarf wedgemussel (Alasmidonta heterodon) in the USA.

Host suitability of 33 fish species for dwarf wedgemussel glochidia (larvae) from the Delaware and Connecticut river basins was tested in laboratory experiments over 9 years. Relative suitability of three different populations of a single host fish, the tessellated darter (Etheostoma olmstedi), from locations in the Connecticut, Delaware, and Susquehanna river basins, was also tested.

Connecticut River basinA. heterodonmetamorphosed into juvenile mussels on tessellated darter, slimy sculpin (Cottus cognatus), and Atlantic salmon (Salmo salar) parr. Delaware River basin mussels metamorphosed using these three species, as well as brown trout (Salmo trutta), banded killifish (Fundulus diaphanus), mottled sculpin (Cottus bairdii), striped bass (Morone saxatilis), and shield darter (Percina peltata). Atlantic salmon, striped bass, and sculpins were highly effective hosts, frequently generating 5+ juveniles per fish (JPF) and metamorphosis success (MS; proportion of attaching larvae that successfully metamorphose) ≥ 0.4, and producing juveniles in repeated trials.

In experiments on tessellated darters, mean JPF and MS values decreased as isolation between the mussel source (Connecticut River) and each fish source increased; mean JPF = 10.45, 6.85, 4.14, and mean MS = 0.50, 0.41, and 0.34 in Connecticut, Delaware, and Susquehanna river darters, respectively. Host suitability of individual darters was highly variable (JPF = 2–11; MS = 0.20–1.0).

The results show that mussel–host fish compatibility inA. heterodondiffers among Atlantic coastal rivers, and suggest that hosts including anadromous Atlantic salmon and striped bass may help sustainA. heterodonin parts of its range. Continued examination of host use variation, migratory host roles, and mussel–fish interactions in the wild is critical in conservation ofA. heterodonand other vulnerable mussel species.
Stability Analysis of Periodic Solution for a Complex‐valued Neural Networks With Bounded and Unbounded Delays
Authors: Du Bo
Published: August 2017

This paper is devoted to investigating a class of complex‐valued neural networks with bounded and unbounded delays. By means of Mawhin's continuation theorem, some criteria on existence and uniqueness of periodic solution are established for the complex‐valued neural networks. By constructing an appropriate Lyapunov‐Krasovskii functional and M−matrix theory, some sufficient conditions are derived for the global exponential stability of periodic solutions to the complex‐valued neural networks. Finally, two numerical examples are given to show the effectiveness and merits of the present results.
Malformations Surveillance: Comparison between Findings at Birth and Age 1 Year
Authors: Thomas Emma G. , Higgins Cathleen , Westgate Marie‐Noel , Lin Angela E. , Anderka Marlene , Holmes Lewis B.
Published: August 2017

Background

Malformations surveillance programs among newborn infants are used to determine the prevalence of congenital anomalies. A comparison in the same group of infants between the malformations detected at birth and those detected at 1 year of age will identify errors in the surveillance process and, also, the abnormalities more likely not to be detected at birth, but later in the first year of life.

Methods

The malformations identified at birth by Brigham and Women's Hospital (BWH) in the years 2000 and 2005 have been compared with the abnormalities detected in the same infants up to age 1 year by the Massachusetts Birth Defects Monitoring Program.

Results

The Massachusetts Birth Defects Monitoring Program identified 557 malformed infants in 2000 and 415 in 2005. Of these, 34 (3.5%) of the malformed infants were missed at birth by BWH Surveillance Program. An additional 22 (2.3%) malformed infants had delayed detection, as they were identified later in the first year. The reasons were the fact that: (1) the Surveillance staff reviewed the physicians’ recorded findings only on the first day of life; (2) failure of the examining pediatrician to record the presence of a malformation in her/his notes. The most common abnormalities with delayed detection were mild heart defects, such as atrial septal defects.

Conclusion

These findings emphasize the importance in a newborn malformations surveillance program of continued follow up in the first days of life, especially in small, premature infants. Birth Defects Research 110:142–147, 2018. © 2017 Wiley Periodicals, Inc.
Anatomic characterization of the humeral nutrient artery: Application to fracture and surgery of the humerus
Authors: Ichimura Koichiro , Kinose Shota , Kawasaki Yuto , Okamura Taro , Kato Kota , Sakai Tatsuo
Published: August 2017

Anatomic characterization of the humeral nutrient artery varies among the several textbooks on human anatomy. To clarify the anatomic characteristics of the humeral nutrient artery, we reexamined its origin and course by cadaveric dissection. In typical cases, one prominent nutrient foramen was situated on the anteromedial surface of the humeral shaft, and the nutrient canal distally penetrated the cortical bone layer. The humeral nutrient artery originated from the brachial artery below the level of the nutrient foramen as a short ascending branch. On reaching near the nutrient foramen, the humeral nutrient artery formed a hairpin loop on the periosteum to enter into the nutrient foramen. In some cases, an accessory nutrient foramen was also found near the groove for the radial nerve on the posterior surface of the humerus. This accessory nutrient foramen received an accessory humeral nutrient artery that originated from the radial collateral artery. The present findings corresponded well with the descriptions in the anatomy textbooks published in English‐speaking countries. However, textbooks published in German‐speaking countries describe only one type of humeral nutrient artery, the branch of the profunda brachii artery. Terminologia Anatomica, the international standard in human anatomic terminology, most likely adopted the description in the German anatomy textbooks, and thus, it is necessary to correct the position of the humeral nutrient artery in the hierarchy of Terminologia Anatomica for accurate morphological description. Clin. Anat. 30:978–987, 2017. © 2017 Wiley Periodicals, Inc.
Chaetochromones A – C, Three New Polyketides from Mangrove Plant Derived Endophytic Fungus Phomopsis sp. SCSIO 41006
Authors: Ju Zhi‐Ran , Lin Xiu‐Ping , Li Minke , Wang Ying , Tian Yong‐Qi , Wang Jun‐Feng , Liu Juan , Tu Zhengchao , Xu Shi‐Hai , Liu Yonghong
Published: August 2017

Three new polyketides, chaetochromones A – C (1 – 3), together with a chromone (4), were isolated from the ethyl acetate extract of mangrove‐derived fungus Phomopsis sp. SCSIO 41006. Their structures were elucidated by means of spectroscopic techniques (UV, IR, MS, 1D‐ and 2D‐NMR). The absolute configurations of the new compounds were established by CD data.
Extending the Scope of GTFR Glucosylation Reactions with Tosylated Substrates for Rare Sugars Synthesis
Authors: Görl Julian , Possiel Christian , Sotriffer Christoph , Seibel Jürgen
Published: August 2017

Functionalized rare sugars were synthesized with 2‐, 3‐, and 6‐tosylated glucose derivatives as acceptor substrates by transglucosylation with sucrose and the glucansucrase GTFR from Streptococcus oralis. The 2‐ and 3‐tosylated glucose derivatives yielded the corresponding 1,6‐linked disaccharides (isomaltose analogues), whereas the 6‐tosylated glucose derivatives resulted in 1,3‐linked disaccharides (nigerose analogue) with high regioselectivity in up to 95 % yield. Docking studies provided insight into the binding mode of the acceptors and suggested two different orientations that were responsible for the change in regioselectivity.
Robotic technology in interventional cardiology: Current status and future perspectives
Authors: Mahmud Ehtisham , Pourdjabbar Ali , Ang Lawrence , Behnamfar Omid , Patel Mitul P. , Reeves Ryan R.
Published: August 2017

Robotic technology has been utilized in cardiovascular medicine for over a decade, and over that period, its use has been expanded to percutaneous coronary and peripheral vascular interventions. The safety and feasibility of robotically assisted percutaneous cardiovascular interventions has been demonstrated in studies including simple to complex coronary lesions, and both iliac and femoropopliteal lesions. These reports have shown that robotically assisted PCI significantly reduces operator exposure to harmful ionizing radiation without a detrimental effect on procedural success or clinical efficacy. Additionally, the use of robotics has the intuitive benefit of alleviating the risk of orthopedic injuries faced by interventional operators. In addition to the interventional operator benefits, robotically assisted intervention has the potential for patient level benefit by allowing more accurate lesion length measurement, precise stent placement, and lower patient radiation exposure. However, further investigation is required to fully elucidate these potential benefits.
Utility of the guideliner catheter for percutaneous coronary interventions in patients with prior transcatheter aortic valve replacement
Authors: Bharadwaj Aditya S. , Bhatheja Samit , Sharma Samin K. , Kini Annapoorna S.
Published: August 2017

The safety and utility of GuideLiner catheters in complex percutaneous coronary interventions (PCI) has been well established. Patients with prior trans‐catheter aortic valve replacement especially with CoreValve, who present for PCI, pose a unique set of challenges. Not only does the operator often encounter difficulty with selective engagement of coronary ostia through the struts of the CoreValve, but also the complex nature of the underlying CAD in this high‐risk population. We present a case series to illustrate the use of GuideLiner catheter as an adjunctive tool for PCI in this patient population.
Designing an O2‐Insensitive Glucose Oxidase for Improved Electrochemical Applications
Authors: Tremey Emilie , Stines‐Chaumeil Claire , Gounel Sébastien , Mano Nicolas
Published: August 2017

The O2 reactivity of flavoproteins and particularly, glucose oxidase, is a limitation for numerous biotechnological applications, and this has been the subject of intense research. In the present study, we performed site‐directed mutations on Val464 of GOx from Penicilium amagasakiense and combined steady‐state, rapid kinetics and electrochemistry to investigate the effect of such mutations on the O2 reactivity. We propose that replacing the non‐polar Valine with a polar Serine permits to decrease the diffusion/stabilization of O2 near the active redox center without altering the oxidation of glucose. When incorporated in osmium hydrogels, the resulting electrodes were insensitive to O2 in the 0.5–60 mM glucose concentration range and were 4.7 times more stable under continuous operation than similar electrodes made with the native GOx. To the best of our knowledge, this is the first example in which O2 sensitivity in GOx can be significantly decrease without altering the electrochemical efficiency for glucose oxidation.
A Highly Sensitive Bimodal Detection of Amine Vapours Based on Aggregation Induced Emission of 1,2‐Dihydroquinoxaline Derivatives
Authors: Alam Parvej , Leung Nelson L. C. , Su Huifang , Qiu Zijie , Kwok Ryan T. K. , Lam Jacky W. Y. , Tang Ben Zhong
Published: August 2017

The detection of food spoilage is a major concern in food safety as large amounts of food are transported globally. Direct analysis of food samples is often time‐consuming and requires expensive analytical instrumentation. A much simpler and more cost‐effective method for monitoring food fermentation is to detect biogenic amines generated as a by‐product during food decomposition. In this work, a series of 1,2‐dihydroquinoxaline derivatives (DQs) with aggregation‐induced emission (AIE) characteristics were synthesised and their protonated forms, that is, H+DQs, can be utilised for the sensitive detection of biogenic amines. For example, upon exposure to amine vapours, deprotonation occurs that converts the red‐coloured, non‐emissive H+DQ2 back to its yellow‐coloured, fluorescent parent form. The bimodal absorption and emission changes endow the system with high sensitivity, capable of detecting ammonia vapour at a concentration of as low as 690 ppb. Taking advantage of this, H+DQ2 was successfully applied for the detection of food spoilage and was established as a robust and cost effective technique to monitor food safety.
Organocatalytic Highly Regio‐ and Enantioselective Umpolung Michael Addition Reaction of α‐Imino Esters
Authors: Yoshida Yasushi , Mino Takashi , Sakamoto Masami
Published: August 2017

The catalytic asymmetric umpolung reaction of ketimines is of great importance, because it can easily provide chiral amines bearing a tetrasubstituted carbon atom on its asymmetric center. Because amino acids with a tetrasubstituted carbon center are useful due to their wide applicability as pharmaceuticals and chiral building blocks, their enantioselective synthesis has great significance in organic synthesis. Herein, we demonstrate a metal‐free novel phase‐transfer‐catalyzed highly regio‐ and enantioselective umpolung Michael reaction of α‐imino esters, which provides amino acid derivatives in high yields with up to 98 % ee. The products are successfully converted into chiral amino acid derivative and δ‐lactone with high enantiopurity.
From an Easily Accessible Pentacarbonylcobalt(I) Salt to Piano‐Stool Cations [(arene)Co(CO)2]+
Authors: Meier Stefan C. , Holz Albina , Schmidt Alexei , Kratzert Daniel , Himmel Daniel , Krossing Ingo
Published: August 2017

The facile synthesis of a pentacarbonyl cobalt(I) salt without the need for a superacid as solvent is presented. This salt, [Co(CO)5]+[Al(ORF)4]− {RF=C(CF3)3}, readily accessible on a multigram scale, undergoes substitution reactions with arenes yielding the hitherto unknown class of two‐legged cobalt piano‐stool complexes [(arene)Co(CO)2]+ with four different arene ligands. Such a substitution chemistry would have been impossible in superacid solution, as the arenes used would have been oxidized and/or protonated. Thus, the general approach described herein may have a wide synthetic use. Additionally, the thermochemistry of the piano‐stool complexes is shown to be not easy to describe computationally and most of the established DFT methods overestimate the reaction energies. Only CCSD(T) calculations close to the basis set limit gave energies fully agreeing with the experiment.
Indole‐ and Pyrrole‐BX: Bench‐Stable Hypervalent Iodine Reagents for Heterocycle Umpolung
Authors: Caramenti Paola , Nicolai Stefano , Waser Jerome
Published: August 2017

The one‐step synthesis of the bench‐stable hypervalent iodine reagents IndoleBX and PyrroleBX using mild Lewis acid catalyzed conditions is reported. The new reagents are stable up to 150 °C and were applied in the C−H arylation of unactivated arenes using either rhodium or ruthenium catalysts. A broad range of heterocyclic systems of high interest for synthetic and medicinal chemistry was accessed in high yields. The developed C−H functionalization could not be achieved using reported reagents or methods, highlighting the unique reactivity of Indole‐ and Pyrrole‐BX.
Red color in flags: A signal for competition
Authors: Zhang Tengxiao , Feng Shiyu , Han Buxin , Sun Si
Published: August 2017

The color‐in‐context theory and ecological valence theory suggest that color preference depends on the context and ecological object that define the psychological meanings of colors. The present study was conducted to identify the preference for the color red in national flags across the world. We explored 192 national flags across the world and found that red was the most frequently used color. Through a systemic examination of symbolic meanings behind use of the color red in flags, it was also found that the color red was often attached with an aggressive connotation. In contrast, the flags of the selected international collaborative organizations did not appear to prefer red. These results support the hypothesis of “red flag preference” in real‐world competitive contexts. Limitations and future research directions are also discussed.
A Hydrogel/Carbon‐Nanotube Needle‐Free Device for Electrostimulated Skin Drug Delivery
Authors: Guillet Jean‐François , Flahaut Emmanuel , Golzio Muriel
Published: August 2017

The permeability of skin allows passive diffusion across the epidermis to reach blood vessels but this is possible only for small molecules such as nicotine. In order to achieve transdermal delivery of large molecules such as insulin or plasmid DNA, permeability of the skin and mainly the permeability of the stratum corneum skin layer has to be increased. Moreover, alternative routes that avoid the use of needles will improve the quality of life of patients. A method known as electropermeabilisation has been shown to increase skin permeability. Herein, we report the fabrication of an innovative hydrogel made of a nanocomposite material. This nanocomposite device aims to permeabilise the skin and deliver drug molecules at the same time. It includes a biocompatible polymer matrix (hydrogel) and double‐walled carbon nanotubes (DWCNTs) in order to bring electrical conductivity and improve mechanical properties. Carbon nanotubes and especially DWCNTs are ideal candidates, combining high electrical conductivity with a very high specific surface area together with a good biocompatibility when included into a material. The preparation and characterization of the nanocomposite hydrogel as well as first results of electrostimulated transdermal delivery using an ex vivo mouse skin model are presented.
A Highly Stereoselective and Efficient Catalytic Approach for the Synthesis of trans‐Stilbene–Arenes as π‐Conjugated Materials
Authors: Majchrzak Mariusz , Wilkowski Grzegorz , Kubicki Maciej
Published: August 2017

The potential expansion of the variety of catalytic methods for carbon–carbon bond formation is explored in many research centers all over the world. In this work, we describe very precise and controlled catalytic transformations as useful tools for the synthesis of new trans‐π‐conjugated molecular organic compounds. The combination of Suzuki–Miyaura coupling and cross‐metathesis reactions is established as a simple and efficient method for the design of new (E)‐stilbenes in the presence of well‐defined transition‐metal catalysts at 0.0001–1 % loadings. All of the desired products are isolated in good‐to‐excellent yields (up to 96 % isolated yield) with high purity.
Oxidative Cross‐Coupling of Substituted Phenols with Unactivated Aromatics
Authors: More Nagnath Yadav , Jeganmohan Masilamani
Published: August 2017

A regioselective C–H arylation of substituted phenols or naphthols with substituted aromatics in the presence of K2S2O8 and Bu4N+·HSO4– in CF3COOH at ambient temperature providing unsymmetrical biaryls is described. The cross‐coupling reaction is compatible with various substituted phenols and aromatics. Based on oxidation potential studies, it was observed that phenols with oxidation potentials up to 0.68 V and naphthols up to 0.88 V were compatible with the reaction. The cross‐coupling reaction proceeds through the reaction of K2S2O8 with substituted phenol, providing a cationic phenol radical intermediate that was further converted into the phenoxy radical intermediate by the dissociation of H+. Subsequent radical‐anion coupling of the phenoxy radical intermediate with a substituted aromatic affords the cross‐coupling product. The formation of a cationic phenol radical intermediate and phenoxy radical intermediate were confirmed by UV/Vis and EPR studies.
Synthesis of Amines, Carbamates and Amides by Multi‐Step Continuous Flow Synthesis
Authors: Sagandira Cloudius R. , Watts Paul
Published: August 2017

We report the continuous flow synthesis of acyl azides in various continuous flow systems and demonstrate that liquid–liquid separation may be incorporated to prepare anhydrous solutions of the acyl azide, which may be subsequently reacted with appropriate nucleophiles to prepare amines, carbamates and amides within a fully integrated multi‐step process in high yields (> 80 %). Interesting effects were also observed when preparing carbamates with long chain alcohols, whereby as the chain length of the alcohol increased the products could be made in high yield even without incorporation of the liquid–liquid separation module.
Stereocontrolled [11C]Alkylation of N‐Terminal Glycine Schiff Bases To Obtain Dipeptides
Authors: Filp Ulrike , Pekošak Aleksandra , Poot Alex J. , Windhorst Albert D.
Published: August 2017

The use of various quaternary ammonium salts as chiral phase‐transfer catalysts allowed effective and stereoselective radiochemical [11C]alkylation to obtain functionalized dipeptides. We herein report a broadly applicable procedure for the asymmetric [11C]alkylation of dipeptides to give labeled N‐terminal peptides by using different [11C]alkyl halides. Contended stereoselectivities of the reactions were observed by using 11C‐labeled alkyl halides, [11C]methyl iodide and [11C]benzyl iodide, and diastereomeric ratios with different specialized catalysts of 95:5 and 90:10 were achieved, respectively. Accordingly, the straightforward synthesis of enantioenriched compounds should play a vital role in peptide‐based radiopharmaceutical development and positron emission tomography imaging.
Validation of the modified 4‐tiered categorization system through comparison with the 5‐tiered categorization system of the 2015 American Thyroid Association guidelines for classifying small thyroid nodules on ultrasound
Authors: Lee Ji Hye , Han Kyunghwa , Kim Eun‐Kyung , Moon Hee Jung , Yoon Jung Hyun , Park Vivian Y. , Kwak Jin Young
Published: August 2017

Background

The purpose of this study was to validate the modified 4‐tiered categorization system and to compare stratification of malignancy risk in small thyroid nodules with the 2015 American Thyroid Association (ATA) management guidelines.

Methods

From January 2015 to December 2015, 737 thyroid nodules measured ≥ 1 cm and <2 cm were included in this study. Each nodule was assigned a category with the ultrasonographic patterns described by the 2015 ATA guidelines.

Results

On univariate analysis, there was no difference of malignancy risk between low suspicion and very low suspicion nodules (P = .584). Therefore, we suggested a modified 4‐tiered categorization, which combines very low suspicion and low suspicion nodules into the “revised low suspicion” category. Specificity, positive predictive value (PPV) and accuracy were higher with the modified 4‐tiered categorization system (P < .001 for all).

Conclusion

The modified 4‐tiered categorization system allows more efficient management with better diagnostic performance than the 2015 ATA categorization system in small thyroid nodules.
Bidirectional stream–groundwater flow in response to ephemeral and intermittent streamflow and groundwater seasonality
Authors: Zimmer Margaret A. , McGlynn Brian L.
Published: August 2017

It is often assumed that the net groundwater flow direction is towards the channel in headwater streams in humid climates, with magnitudes dependent on flow state. However, studies that characterize stream–groundwater interactions in ephemeral and intermittent streams in humid landscapes remain sparse. Here, we examined seasonally driven stream–groundwater interactions in response to temporary streamflow on the basis of field observations of streamflow and groundwater on an adjacent hillslope. The direction of hydraulic head gradients between the stream and groundwater shifted seasonally. The stream gained water (head gradients were towards the stream) when storage state was high. During this period, streamflow was persistent. The stream lost water to the groundwater system (head gradients were away from the stream) when storage state was low. During this period, streamflow only occurred in response to precipitation events, and head gradients remained predominantly away from the stream during events. This suggested that mechanisms other than deep groundwater contributions produced run‐off when storage was low, such as surface and perched subsurface flowpaths above the water table. Analysis of the annual water balance for the study period showed that the residual between precipitation inputs and streamflow and evapotranspiration outputs, which were attributed to the loss of water to the deeper, regional groundwater system, was similar in magnitude to streamflow. This, coupled with results that showed bidirectionality in stream–groundwater head gradients, indicated that headwaters composed of temporary (e.g., ephemeral and intermittent) streams can be important focal areas for regional groundwater recharge, and both contribute to and receive water, solutes, and materials from the groundwater system.
Meta‐analysis of the association between dietary inflammatory index (DII) and cancer outcomes
Authors: Fowler Mackenzie E. , Akinyemiju Tomi F.
Published: August 2017

Proinflammatory dietary patterns have been associated with increased cancer risk and mortality. We present a systematic review and meta‐analysis of the current published literature on a dietary inflammatory index (DII) score and its association with cancer risk and mortality outcomes. Published articles from online databases (PubMed, Scopus, and Embase) examining the association between DII and any cancer risk, incidence, or mortality between 1980 and November 2016 were selected for review. Results of studies meeting inclusion criteria were summarized and meta‐analyzed using STATA to generate summary measures of association across studies. Sixty‐three published articles were identified from the search, and following title, abstract and full‐text review, twenty‐four studies met inclusion criteria. All articles calculated DII scores based on study‐specific food‐frequency questionnaires using methodology from the same article. Of the 24 included studies, 13 were case–control, 6 were prospective cohort, 1 was a retrospective cohort, 3 were RCTs, and 1 did not specify study design. The most common cancers examined were colorectal, breast, lung, and prostate. Individuals in the highest versus lowest DII categories had 25% increased risk of overall cancer incidence (RR: 1.25, 95% CI: 1.16–1.35), 75% higher odds of cancer (OR: 1.75, 95% CI: 1.43–2.16) and 67% increased risk of cancer mortality (RR: 1.67, 95% CI: 1.13–2.48). Upon stratification for cancer type, positive associations remained (RRbreast: RR: 1.12, 95% CI: 1.03–1.22) (RRcolorectal: 1.33, 95% CI: 1.22–1.46) (RRlung: 1.30, 95% CI: 1.13–1.50). There were consistent and significant positive associations between higher DII and cancer incidence and mortality across cancer types, study populations, and study design.
Prostate and breast cancer in four Nordic countries: A comparison of incidence and mortality trends across countries and age groups 1975–2013
Authors: Kvåle R. , Myklebust T.Å. , Engholm G. , Heinävaara S. , Wist E. , Møller B.
Published: August 2017

In recent decades, management of prostate and breast cancer patients has changed considerably. The purpose of our study is to interpret patterns of prostate and breast cancer incidence and mortality in four Nordic countries across age groups and time periods. Prostate and breast cancer incidence and mortality data (1975–2013) were obtained from the NORDCAN database. Joinpoint regression models were used to identify changes in the trends. A more prominent increase in prostate than breast cancer incidence was observed. From the mid‐1990s, mortality rates in patients below 75 years of age have decreased for both cancers in all four countries. The relative decline in breast cancer mortality from 1985–1989 to 2009–2013 were largest in women under 50 years of age, with reductions in mortality rates ranging from 38% in Finland to 55% in Denmark. In the age group 55–74 years, mortality rates for prostate cancer declined more than for breast cancer in all countries except Denmark, ranging from 14% in Denmark to 39% in Norway. The substantial decrease in breast cancer mortality in women below regular screening age and the reductions in mortality from both cancers in Denmark from the mid‐1990s are consistent with beneficial contributions from improved treatment besides mammography screening and increased PSA testing. Alongside similar mortality decreases, the larger increases in prostate cancer incidence as compared to breast cancer indicate that a higher proportion of prostate cancer cases are overdiagnosed.
Disulfide‐bond‐containing agamatine‐cystaminebisacrylamide polymer demonstrates better transfection efficiency and lower cytotoxicity than polyethylenimine in NIH/3T3 cells
Authors: Yang Zhen , Sun Yanping , Xian Lei , Xun Zhe , Yu Jiankun , Yang Tianzhi , Zhao Xiaoyun , Cai Cuifang , Wang Dongkai , Ding Pingtian
Published: August 2017

Previously, we synthesized a non‐viral vector containing disulfide bond by polymerization of agamatine (AGM) and N,N′‐cystaminebisacrylamide (CBA). In this study, we investigated the transfection efficiency of disulfide bond (SS) containing AGM‐CBA polymer in gene delivery into NIH/3T3 cells, and examined the factors affecting its transfection efficiency by comparing with polyethylenimine (PEI). In addition, experiments were carried out to determine the mechanisms of cell entry pathways and intracellular behavior of AGM‐CBA/pDNA polyplexes. The transfection efficiency of AGM‐CBA/pDNA with different weight ratios and different amounts of pDNA was measured and the pathways mediated transfection processes were studied by using various endocytosis inhibitors. To determine the intracellular behavior of AGM‐CBA/pDNA polyplexes, the transfection efficiencies of AGM‐CBA/pDNA and PEI/pDNA polyplexes with different combination structures were determined by using reporter gene and fake plasmid DNA. The transfection efficiency of AGM‐CBA/pDNA polyplexes was correlated with its weight ratio of AGM‐CBA and pDNA, and the amount of pDNA. Both AGM‐CBA/pDNA and PEI/pDNA polyplexes enter into cell by clathrin‐ and caveolae‐mediated endocytic pathways. However, AGM‐CBA/pDNA showed different intracellular behavior in NIH/3T3 cells compared to PEI/pDNA polyplexes. It was hypothesized that disulfide bond in AGM‐CBA could be an important factor contributing to its intracellular behavior and better transfection efficiency. Overall, AGM‐CBA demonstrated better transfection efficiency and lower cytotoxicity than PEI in NIH/3T3 cells as a gene delivery vector.
Retracted: Effects of gene knockdown of CNP on ventricular remodeling after myocardial ischemia‐reperfusion injury through NPRB/Cgmp signaling pathway in rats
Authors: Wu Lian‐He , Zhang Qi , Zhang Shen , Meng Lu‐Yu , Wang Yan‐Chi , Sheng Cun‐Jian
Published: August 2017

This study aimed to explore effects of CNP on ventricular remodeling following myocardial ischemia‐reperfusion (I/R) injury through the NPRB/cGMP signaling pathway. Rat cardiomyocytes were assigned into: control, I/R, I/R + CNP, and I/R + 8‐Br‐cGMP groups. ELISA, qRT‐PCR, and Western blotting were used to detect cGMP content and expression, respectively. After model establishment of I/R rats, normal control, CNP−/− control, I/R, and CNP−/− groups were set. Indexes of heart were detected using echocardiography and hemodynamics. ELISA was used to measure serum CNP, cGMP, LDH, cTn I, CK‐MB, TNF‐α, and IL‐6 levels. Myocardial infarct was identified by TTC staining, and apoptosis conditions by TUNEL staining. QRT‐PCR and Western blotting were adopted to detect expressions of CNP, NPRB, cGMP, and apoptosis‐related genes. Compared with control group, cGMP contents and expression in the I/R, I/R + CNP and I/R + 8‐Br‐cGMP groups were decreased. Levels of LVEDV, LVESV, LVDS, LVDD, IVSD, LVM, LVEDP, and LVSP were higher in the I/R, CNP−/− control, and CNP−/−groups than normal control group while LVEF, SV, CO, and ±dp/dtmax were lower. Compared with the normal control group, LDH, cTn I, CK‐MB, TNF‐α, and IL‐6 were higher in the I/R, CNP−/− control and CNP−/− groups; pathological changes and myocardial infarction were observed in the I/R, CNP−/− control, and CNP−/− groups; expressions of apoptosis‐related genes in those groups were higher; while CNP, NPRB, cGMP, and Bcl‐2 expressions were decreased. We came to the conclusion that gene knockdown of CNP blocks the NPRB/cGMP signaling pathway, thereby aggravating myocardial I/R injury and causing ventricular remodeling in rats.
Computerized implementation of higher‐order electron‐correlation methods and their linear‐scaling divide‐and‐conquer extensions
Authors: Nakano Masahiko , Yoshikawa Takeshi , Hirata So , Seino Junji , Nakai Hiromi
Published: August 2017

We have implemented a linear‐scaling divide‐and‐conquer (DC)‐based higher‐order coupled‐cluster (CC) and Møller–Plesset perturbation theories (MPPT) as well as their combinations automatically by means of the tensor contraction engine, which is a computerized symbolic algebra system. The DC‐based energy expressions of the standard CC and MPPT methods and the CC methods augmented with a perturbation correction were proposed for up to high excitation orders [e.g., CCSDTQ, MP4, and CCSD(2)TQ]. The numerical assessment for hydrogen halide chains, polyene chains, and first coordination sphere (C1) model of photoactive yellow protein has revealed that the DC‐based correlation methods provide reliable correlation energies with significantly less computational cost than that of the conventional implementations. © 2017 Wiley Periodicals, Inc.
Implications of potential evapotranspiration methods for streamflow estimations under changing climatic conditions
Authors: Seong Chounghyun , Sridhar Venkataramana , Billah Mirza M.
Published: August 2017

Several potential evapotranspiration (PET) estimation methods are commonly used to quantify water and energy budgets. As each PET method can differ, their effects on projected streamflows under changing climatic conditions are critical to quantify the sensitivities of these methods. We used the Coupled Model Intercomparison Project (CMIP5) climate dataset and Hydrological Simulation Program – FORTRAN (HSPF) model to compare the following five PET methods [Hargreaves (HG), Hamon (HM), Thornthwaite (TW), Priestley–Taylor (PT) and Penman–Monteith (PM)] for the Susquehanna River Basin in the northeastern United States. As PET is used as an input, various configurations of HSPF driven by these five PET estimates were used to calibrate HSPF with observed streamflow data from 41 gaging stations. We also used nine global climate model inputs to derive five PET estimates, which were subsequently used as inputs to compute streamflow projections for 2020–2099. An increase in precipitation from 6.2 to 7.2% and an increase in temperature from 1.8 to 2.7 °C were projected, while changes in PET and actual evapotranspiration (AET) were found to substantially differ among the PET methods. The HM method shows an increase in AET of between 14 and 24%, while the other methods show an increase of between 7 and 12%. It is concluded that streamflow projections are sensitive to the selection of the PET methods in the HSPF model; a decrease of up to 5.5% and increase of up to 3.6% are projected for PET levels estimated by using the HM and HG methods, respectively; and both HM and TW are found to be suitable for simple seasonal water balance analyses conducted at regional scales.