bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploitation of Eu3+ red luminescence through order–disorder structural transitions in lanthanide stannate pyrochlores for warm white LED applications
Authors: Sreena T. S. , Prabhakar Rao P. , Raj Athira K. V. , Aju Thara T. R.
Published: August 2018

The structural transition from an ordered pyrochlore to a fluorite-type structure in Ln2.85YSnNbO10.5:0.15Eu3+ (Ln = La, Gd, Y, and Lu) provides a gateway for exploiting Eu3+ red luminescence for warm white LED applications.
Hydrodebromination of allylic and benzylic bromides with water catalyzed by a rhodium porphyrin complex
Authors: Yang Wu , Chen Chen , Chan Kin Shing
Published: August 2018

Rhodium porphyrin catalyzed hydrodebromination of activated organic bromides with water.
Molecular engineered rhenium(i) carbonyl complexes to promote photoisomerization of coordinated stilbene-like ligands in the visible region
Authors: Amaral Ronaldo C. , Murakami Iha Neyde Y.
Published: August 2018

Novel fac-[Re(CO)3(dmcb)(trans-stpyR)]+ complexes have been judiciously engineered to absorb at lower energies and sensitize trans-4-styrylpyridine (trans-stpy) or trans-4-(4-cyano)styrylpyridine (trans-stpyCN) photoisomerizable ligands up to 436 nm of irradiation.
Correction: Water oxidation by a copper(ii) complex: new findings, questions, challenges and a new hypothesis
Authors: Mahdi Najafpour Mohammad , Mehrabani Somayeh , Mousazade Younes , Hołyńska Małgorzata
Published: August 2018

Correction for ‘Water oxidation by a copper(ii) complex: new findings, questions, challenges and a new hypothesis’ by Mohammad Mahdi Najafpour et al., Dalton Trans., 2018, 47, 9021–9029.
A smart hemicapsule with multiple dynamic functions
Authors: Chen Chi-An , Li Chia-Chen , Chen Chih-Hsien
Published: August 2018

A new smart carrier particle—a hemicapsule which has an adjustable half-solid–half-hollow structure with multiple dynamic functions—is synthesized.
Design, physico-chemical and pre-clinical evaluation of a homo-bivalent99mTc-(BTZ)2DTPA radioligand for targeting dimeric 5-HT1A/5-HT7receptors
Authors: Jha Preeti , Chaturvedi Shubhra , Kaul Ankur , Pant Pradeep , Anju Anju , Pal Sunil , Jain Nidhi , Mishra Anil K.
Published: August 2018

A99mTc-labelled bis-benzothiazolone-DTPA radio-complex as a SPECT neuroimaging agent.
Correction: Effect of ionic size compensation by Ag+ incorporation in homogeneous Fe-substituted ZnO: studies on structural, mechanical, optical, and magnetic properties
Authors: Bajpai Gaurav , Srivastava Tulika , Patra N. , Moirangthem Igamcha , Jha S. N. , Bhattacharyya D. , Riyajuddin Sk , Ghosh Kaushik , Basaula Dharma R. , Khan Mahmud , Liu Shun-Wei , Biring Sajal , Sen Somaditya
Published: August 2018

Correction for ‘Effect of ionic size compensation by Ag+ incorporation in homogeneous Fe-substituted ZnO: studies on structural, mechanical, optical, and magnetic properties’ by Gaurav Bajpai et al., RSC Adv., 2018, 8, 24355–24369.
Silk-based systems for highly efficient photothermal conversion under one sun: portability, flexibility, and durability
Authors: Zhang Qian , Xiao Xingfang , Wang Gang , Ming Xing , Liu Xinghang , Wang Han , Yang Hongjun , Xu Weilin , Wang Xianbao
Published: August 2018

A portable, flexible, and durable reduced graphene oxide–silk fabric (RGO–silk-fabric) is developed for solar steam generation with remarkably high photothermal performances and a stable water output of 1.48 kg m−2 h−1 under one sun irradiation.
Thermal stability of Mg3Sb1.475Bi0.475Te0.05 high performance n-type thermoelectric investigated through powder X-ray diffraction and pair distribution function analysis
Authors: Jørgensen Lasse Rabøl , Zhang Jiawei , Zeuthen Christian Bonar , Iversen Bo Brummerstedt
Published: August 2018

The thermal stability of the high performance n-type Te-doped Mg3Sb1.5Bi0.5 system is investigated.
An ultralight and flexible sodium titanate nanowire aerogel with superior sodium storage
Authors: Tran Ngoc Quang , Le Thi Anh , Lee Hyoyoung
Published: August 2018

An ultralight, conductive, and flexible 3D assembly of a metal oxide nanowire aerogel as an electrode for energy storage devices without additives and typically inconvenient flexible supported-substrates remains a challenge.
Asymmetric tris-heteroleptic iridium(iii) complexes containing three different 2-phenylpyridine-type ligands: a new strategy for improving the electroluminescence ability of phosphorescent emitters
Authors: Dang Wanping , Yang Xiaolong , Feng Zhao , Sun Yuanhui , Zhong Daokun , Zhou Guijiang , Wu Zhaoxin , Wong Wai-Yeung
Published: August 2018

A series of asymmetric tris-heteroleptic Ir(iii) phosphorescent complexes adopting chemical constitution of three different ppy-type ligands.
Effects of conjugated bridges on the photovoltaic properties of ortho-functionalized perylene diimides for non-fullerene polymer solar cells
Authors: Wu Jiazun , Li Xiangchun , Liu Xiaodong , Wu Shuanghong , Lai Wen-Yong , Zheng Yonghao
Published: August 2018

The structure of the π-bridge in an ortho-functionalized PDI plays a crucial role in controlling the active layer morphology.
Downlink beamforming scheme for hybrid satellite–terrestrial networks
Authors: Jiang Yang‐Wei , Ouyang Jian , Yin Chun‐Yan , Xu Zhao‐Ye , Tao Xiang‐Shuai , Lou Li
Published: August 2018

Here, the authors propose a beamforming (BF) scheme for the downlink transmission of a hybrid satellite–terrestrial network. The authors first formulate a constrained optimisation problem to maximise the minimal quality‐of‐service of the terrestrial users subject to the interference constraint of the satellite user and the transmit power budget of the base station (BS). Then, by using the uplink–downlink duality theory, the authors design an iterative algorithm to obtain the optimal BF weight vectors as well as the corresponding power coefficients of the considered system. Furthermore, the analytical downlink BF weight vectors are obtained through the equivalence between signal‐to‐leakage‐and‐noise ratio and minimum mean square error. Simulation results are provided to demonstrate the effectiveness of the proposed BF method.
Smart inadvertent islanding detection employing p‐type μPMU for an active distribution network
Authors: Dutta Soham , Sadhu Pradip Kumar , Reddy Maddikara Jaya Bharata , Mohanta Dusmanta Kumar
Published: August 2018

In the smart‐grid paradigm, since distribution systems are controlled by various independent operators, it becomes inevitable for all dispatchers to have a wide‐area view of the network for situational awareness and protection. This visualisation is accomplished with the aid of protection (p) type micro‐phasor measurement unit (μPMU) installed at the bus of the respective distributed generation (DG). One of the pressing issues with DG's is the concern of inadvertent islanding that disrupts orderly reconnection besides posing hazards to utility workers. In view of this, this study proposes a real‐time inadvertent islanding detection by μPMU. The voltage and current phasors obtained from these μPMUs by discrete Fourier transform are further processed by Fortescue transform to compute the angle of sequence components. The absolute angle difference between positive and zero components is used to initiate signal for accomplishing intelligent islanding under islanded condition. The simulation results prove the method to be robust, computationally efficient, non‐detection zone free and feasible. Most significantly, as measuring equipment and relay are already present in p type μPMU, therefore unlike other detection methods, no extra arrangements are required in this method making it economically viable and easy to implement.
Multi‐polarisation electromagnetic energy harvesting with high efficiency
Authors: Ghaderi Bagher , Nayyeri Vahid , Soleimani Mohammad , Ramahi Omar M.
Published: August 2018

This study presents a polarisation‐independent metasurface harvester composed of an ensemble of novel electric‐field‐coupled inductive‐capacitive (ELC) resonators. The ELC resonator has full symmetry in a way that its behaviour is highly insensitive to the polarisation of the incident wave. Loading the resonators with resistors (which model the input impedance of a power combining circuit in a harvesting system), it is shown that the metasurface absorbs the incident electromagnetic wave energy, with nearly unity harvesting efficiency, irrespective of its polarisation while simultaneously delivering the absorbed power to the loads. As a proof of concept, a metasurface harvester composed of a 9 × 9 resonator array working at 2.45 GHz was fabricated. Near‐unity harvesting efficiency of the metasurface was demonstrated using full‐wave numerical simulation for a wide range of polarisation angles. Laboratory tests showed strong agreement between the simulation results and the measurements.
Influence of antenna configuration on mm‐wave MIMO performance in a subway‐like tunnel
Authors: Yin Xiaoyu , Zheng Guoxin , Saleem Asad
Published: August 2018

This study investigates the channel performance of a 28 GHz multiple‐input–multiple‐output (MIMO) system in a subway tunnel, using ray‐tracing‐based simulations and experimental measurements in a realistic tunnel environment. The transmitter (Tx) array was deployed at three positions, i.e. in the centre of the tunnel, close to the sidewalls and under the ceiling. The performance was significantly better in the centre and sidewall positions. Good agreement is obtained between simulation and measurement results. Furthermore, it is inferred that the MIMO channel capacity for the Tx–receiver distance of 60 m is higher than that of 15 m. The angular spread calculated for the 60 m case is also larger than that of the 15 m case.
Human trajectory prediction for automatic guided vehicle with recurrent neural network
Authors: Song Chao , Chen Zhixian , Qi Xiaozhi , Zhao Baoliang , Hu Ying , Liu Shoubin , Zhang Jianwei
Published: August 2018

The accurate prediction of the pedestrian trajectory is necessary to endow automatic guided vehicle with the capabilities to adjust velocity and path dynamically for the navigation in real pedestrian scenes. For this purpose, this study presents a social conscious prediction model considering two main factors that affect the pedestrians’ walking in the crowd – relative distance and moving direction. To form an effective model, the authors’conscious pooling layer is added to the Long Shot Term Memory network (LTSM)model to build the relationship between pedestrians, learning the current position m and movement trend. The experiments are conducted to compare the proposed model with the previous state‐of‐the‐art model on several public datasets. The experimental results show that the proposed model predicts pedestrian trajectories more accurately.
Landlord's equal cards force generation algorithm
Authors: Li Saisai , Li Shuqin , Ding Meng
Published: August 2018

In recent years, deep learning has developed rapidly and gradually infiltrated into various fields. As a rookie, generation‐based confrontation networks based on deep learning show excellent characteristics in many aspects. This study presents two innovative ideas, the same card force and generation cards algorithm. The generation of the equivalent cards force based on the generation of confrontation networks is studied. For the same period of time in the regular game, players will be issued different types of cards with similar card force, so as to distinguish the player level, the theory of the equal force is proposed. Based on the average and variance of scores obtained after the completion of a game, the cards are divided into ten different types of cards. On this basis, the use of generating a counterfeit network Generative Adversarial Nets generates a large number of cards of the equal card force. In the actual game, a network model is generated to generate a large number of game cards with the same force and distributed to different table numbers, so that the points scored by the landlords in different matches can have the characteristics of mutual appraisal.
Smartphone‐based speed acquisition and differential evolution modelling for fitness running
Authors: Mei Ermeng , Du Xin , Ni Youcong , Ye Peng , Wu Yandan
Published: August 2018

There are two shortcomings in Brzostowski's method of modelling for fitness running. One is the low precision of speed acquisition by smartphones. The other is the limited search ability of modelling algorithms. As a result, it is difficult to obtain a highly precise model of fitness running. Aiming at the above two problems, a method for multiple sensors of smartphone and median filter for speed data acquisition in fitness running (MM4SA) is proposed. MM4SA can remove the impulse noise of three‐axis acceleration signal, which is generated by the intermittent gesture changes of smartphones, and filter out the gravitational acceleration from the three‐axis acceleration signal with the help of the orientation sensor. Secondly, the differential evolution modelling algorithm (DEMA) is applied to enlarge search space and find out a better model for fitness running. The experimental results show that the proposed method can obtain more accurate speed and better model for fitness running than Brzostowski's method.
Intelligent identification of gas anomalous area by electro‐magnetic joint exploration technology
Authors: Peng Chen , Tao Yang , Xuexi Chen , Yongjie Liu , Tingxiang Chu
Published: August 2018

For intelligent and accurate identification of the gas anomalous area, two geophysical exploration methods, namely, the direct current (DC) method and the transient electromagnetic method, were adopted for advance detection of the underground roadway before the joint inversion of the detection data to obtain the fusion image of apparent resistivity. Based on the high‐resistivity area in the image, the range of 13–65 m ahead of the driving face is the gas anomalous area. According to the test results of gas prediction indexes q and Δh 2, there is an area with high prediction values in front of the roadway, which is consistent with that determined by geophysical exploration. From the analysis of the thickness of exposed coal, there is an area with large coal thickness ahead of the roadway where there is an increase in gas content. The electrical characteristics of the coal are changed in the area, contributing to the anomalous resistivity, which keeps in consistency with the results of geophysical exploration. Therefore, the electro‐magnetic joint exploration technology can realize the intelligent identification of gas anomalous areas, which is of great significance for the efficient and accurate detection of gas anomalous area in the coal seam.
Multi‐adjoint intuitionistic fuzzy rough sets
Authors: Liang Meishe , Mi Jusheng , Feng Tao , Zhao Tianna
Published: August 2018

The combination of fuzzy information systems (ISs) and multi‐adjoint theory has become a hot issue in the study and applications of artificial intelligence. An intuitionistic fuzzy set has more flexible and practical ability to represent information and is better in dealing with ambiguity and uncertainty when compared with the fuzzy set. Multi‐ adjoint intuitionistic fuzzy rough sets are constructed by using adjoint triples under intuitionistic fuzzy IS. For this purpose, the authors propose intuitionistic fuzzy indiscernibility relation and multi‐adjoint approximation operators. The basic results in the multi‐adjoint fuzzy rough set model are generalised to multi‐adjoint intuitionistic fuzzy rough set model. The analogous results are also verified. After that, a novel approach of attribute reduction is proposed. First, a kind of approximate reduction to keep the dependence of the positive region to a degree is formulated. Second, they propose a heuristic algorithm to compute the attribute reduction. At last, they employ an example to describe the processing of the algorithm.
Image segmentation based on modified superpixel segmentation and spectral clustering
Authors: Yuan Changan , Qin Xiao , Qin Zhengyou , Wang Ruili
Published: August 2018

Spectral clustering has been widely used for image segmentation recently. There are certain issues when using spectral clustering for image segmentation, such as a high complexity. Moreover, it commonly similarity measure is a Gaussian kernel function. However, spectral clustering is very sensitive to the scale parameters in this similarity measure, which is difficult to determine a suitable parameter. For these problems, a modified superpixel segmentation method and a new similarity measure for improving Ng‐Jordan‐Weiss (NJW) method are presented in this study. Then the improved NJW method is applied to image segmentation. In the authors’ scheme, their modified superpixel segmentation method will be utilised to divide the image into several small regions, which are called superpixels. Then, the NJW method is used to cluster these superpixels into some meaningful regions. In NJW, the similarity between two adjacent superpixels is measured by a kernel fuzzy similarity measure. The improving NJW method for image segmentation not only has lower complexity but also not sensitivity to scale parameters. Experimental results have demonstrated that their method visible improvement both in diminishing segmentation error, and also it has a higher efficiency.
Research on initial alignment of vehicle strapdown inertial navigation system
Authors: Jianzhong Wang
Published: August 2018

Due to the impact of the vehicle engine jitter, unevenly inflated tires and people moving, the attitude initial alignment accuracy is not high and the repetition is poor. The author proposed the two‐channel ten state variable error model for land vehicle application, the system for error equation and measurement equation are established to solve the initial alignment problem of strapdown inertial navigation system, and the simulation experiment and the initial comparison of the system static base are carried out, the calculation method of strapdown attitude is optimised and the initial alignment problem in complex environment is solved, which provides a reference for fast initial alignment of the vehicle strapdown inertial navigation system.
Multiple layers uneven clustering algorithm based on residual energy for wireless sensor networks
Authors: Liu Jing , Su Shoubao , Lu Yuhua , Dong Jun
Published: August 2018

Since the node energy is limited, wireless sensor networks need efficient routing algorithms to reduce energy consumption. The authors proposed a multiple layer uneven clustering algorithm. This algorithm is used for single‐hop network. Nodes submit data to the cluster heads, and then all cluster heads submit data to the sink node by single hop. The authors divide the whole network into several layers with different reign. The inner diameter and outer diameter of each layer are calculated by a sink node to meet the aim of balancing energy consumption. The algorithm chooses cluster heads according to the nodes’ residual energy in each layer. According to the reign of each layer, from the perspective of reducing energy consumption, the authors limit the minimum distance between two cluster heads, so that the cluster heads can be distributed evenly in one layer. Simulation results show that the algorithm can promote the lifetime of networks.
Scaling of X-ray spectral properties of a black hole in the Seyfert 1 galaxy NGC7469
Authors: Seifina Elena , Titarchuk Lev , Ugolkova Lyubov
Published: August 2018

We present our analysis of X-ray spectral properties observed from the Seyfert 1 galactic nucleus NGC 7469 using theRossiX-ray Timing Explorer (RXTE) and Advanced Satellite for Cosmology and Astrophysics mission (ASCA) observations. We demonstrate strong observational evidence that NGC 7469 undergoes spectral transitions from the low hard state (LHS) to the intermediate state (IS) during these observations. The RXTE observations (1996–2009) show that the source was in the IS ∼75% of the time only ∼25% of the time in the LHS. The spectra of NGC 7469 are well fitted by the so-called bulk motion Comptonization (BMC) model for all spectral states. We have established the photon index (Γ) saturation level, Γsat= 2.1 ± 0.1, in the Γ versus mass accretion rate,Ṁcorrelation. This Γ –Ṁcorrelation allows us to estimate the black hole (BH) mass in NGC 7469 to beMBH≥ 3 × 106M⊙assuming the distance to NGC 7469 of 70 Mpc. For this BH mass estimate, we use the scaling method taking Galactic BHs, GRO J1655–40, Cyg X–1, and an extragalactic BH source, NGC 4051 as reference sources. The Γ versusṀcorrelation revealed in NGC 7469 is similar to those in a number of Galactic and extragalactic BHs and it clearly shows the correlation along with the strong Γ saturation at ≈2.1. This is robust observational evidence for the presence of a BH in NGC 7469. We also find that the seed (disk) photon temperatures are quite low, of the order of 140–200 eV, which are consistent with a high BH mass in NGC 7469 that is more than 3 × 106solar masses.
Causticum Hahnemannii – Der Hahnemannsche Ätzstoff
Authors: Seyfried Anne-Lore , Milleder Beatrice
Published: August 2018

Es werden ein Kater und ein Hund vorgestellt, die beide erfolgreich mit Causticum Hahnemannii behandelt wurden. Trotz unterschiedlicher Diagnosen führt die Individualisierung – eine wesentliche Säule der Homöopathie – zum Erfolg. Zudem zeigt jeder Patient seine ganz persönlichen Facetten von Causticum, sodass ein guter Gesamteindruck des Mittelbildes entsteht. Spannend ist auch die Repertorisation nach der Methode von Paul Herscu bei Mischling Gismo 2.
„Aerosound“ – ein realitätsnaher Test für die Sprachverständigung der Piloten?
Authors: Uike Kyoko-Nadja , Trabold Katja , Kunz Andres , Briner Hans Rudolf , Bron Denis
Published: August 2018

Die Kommunikation über Funk ist in der Luftfahrtbranche äußerst wichtig. Deshalb gehört die Überprüfung der Hörfähigkeit zur regulären medizinischen Tauglichkeitsuntersuchung. Bisher werden diese Tests nur in Form von Audiometrien in ruhiger Umgebung durchgeführt, was nicht der Realität im Cockpit entspricht. Vor einiger Zeit wurde deshalb das realitätsnahe Testprogramm „Aerosound“ entwickelt: Originalfunkdurchsagen werden abgespielt, während im Hintergrund Cockpitgeräusche zu hören sind. Die Funksprüche müssen anschließend korrekt beantwortet werden, wobei ein wiederholtes Abspielen der Funkdurchsage erlaubt ist. Um die Durchführbarkeit und die Validität von „Aerosound“ zu überprüfen, wurden in einer Pilotstudie Militärpiloten und Piloten mit einer zivilen Fluglizenz (Private Pilote License, PPL) getestet und miteinander verglichen.
Update psychische Gesundheit von Piloten
Authors: Siedenburg Jörg
Published: August 2018

Die Luftfahrt gilt als ultrasicheres System. Fehler, Zwischenfälle und Unfälle können jedoch katastrophale Konsequenzen haben. Wegen der Häufigkeit psychischer Veränderungen in der Allgemeinbevölkerung und deren Zunahme sowie einiger Ereignisse in den letzten Jahren ist das Thema psychische Gesundheit von Piloten zunehmend wichtiger geworden. Der wichtige Einfluss auf die Flugsicherheit wurde von verschiedenen Arbeitsgruppen herausgestellt. Bei den fliegerärztlichen Untersuchungen wird empfohlen, psychische Veränderungen mehr in den Blickpunkt zu nehmen. Deren Anteil an Incapacitations hat im Gegensatz zu den traditionell im Fokus stehenden organischen Veränderungen in den vergangenen Jahren zugenommen. Erschwerend ist die Tatsache, dass die meisten Veränderungen im Intervall zwischen 2 turnusmäßigen Untersuchungen zu erwarten sind. Außerdem erschwert das damit verbundene Stigma die Selbstoffenbarung. Weiterhin liegen im Bereich der Psychologie und Psychiatrie kaum einfache Tests vor, die psychische Veränderungen in der Zukunft ausschließen können. Verschiedene Vorschläge werden diskutiert, die Vorbeugung, Diagnose, damit auch die Möglichkeit einer Behandlung und das Vertrauen zwischen Piloten und Fliegerärzten optimieren sollen.
Intermolecular Stereoselective Iridium-Catalyzed Allylic
Alkylation: An Evolutionary Account
Authors: Stoltz Brian , Shockley Samantha , Hethcox J.
Published: August 2018

Our lab has long been interested in the development of methods for the creation of enantioenriched all-carbon quaternary stereocenters. Historically, our interest has centered on palladium-catalyzed allylic alkylation, though recent efforts have moved to include the study of iridium catalysts. Whereas palladium catalysts enable the preparation of isolated stereocenters, the use of iridium catalysts allows for the direct construction of vicinal stereocenters via an enantio-, diastereo-, and regioselective allylic alkylation. This Account details the evolution of our research program from inception, which focused on the first iridium-catalyzed allylic alkylation to prepare stereodyads containing a single quaternary stereocenter, to our most recent discovery that allows for the synthesis of vicinal quaternary centers.

1 Introduction

2 Synthesis of Vicinal Tertiary and All-Carbon Quaternary Stereocenters via Enantio- and Diastereoselective Iridium-Catalyzed Allylic Alkylation

2.1 Cyclic Nucleophiles

2.2 Acyclic Nucleophiles

2.3 Alkyl-Substituted Electrophiles

3 Umpoled Iridium-Catalyzed Allylic Alkylation Reactions

3.1 Tertiary Allylic Stereocenters

3.2 Quaternary Allylic Stereocenters

4 Synthesis of Vicinal All-Carbon Quaternary Centers via Enantio­selective Iridium-Catalyzed Allylic Alkylation

5 Summary and Future Outlook
Palladium-Catalyzed Reductive Coupling of Nitroarenes with Phenols­ leading to N-Cyclohexylanilines
Authors: He Wei-Min , Liu Kai-Jian , Zeng Xiu-Ling , Zhang Yong , Wang Yi , Xiao Xin-Sheng , Yue Huilan , Wang Ming , Tang Zilong
Published: August 2018

A direct and efficient palladium-catalyzed reductive coupling reaction of nitroarenes with phenols has been developed. A series of N-cyclohexylaniline derivatives was easily and efficiently obtained in moderate to good yields via C–N bond formation by the simple use of safe and inexpensive sodium formate as the hydrogen donor.
Visible-Light-Driven Oxidative Mono- and Dibromination of Benzylic­ sp3 C–H Bonds with Potassium Bromide/Oxone at Room Temperature
Authors: Lu Wenjun , Zhao Mengdi , Li Meiqi
Published: August 2018

Benzylic sp3 C–H bonds have been successfully brominated with potassium bromide by using Oxone as an oxidant in water/dichloromethane under visible light at room temperature. Toluene, ethylbenzene and other alkylbenzenes bearing an electron-withdrawing group, such as Br, Cl, COMe, CO2Et, CO2H, CN or NO2, provide the corresponding benzylic monobromides in good to excellent yields in this reaction. Dibromides can also be produced in the presence of excess potassium bromide in a prolonged reaction time. Control of the illuminance of visible light (~500 lux) is crucial to achieving both high yield and high selectivity in these brominations. Mono- and difluorides can be conveniently prepared through nucleophilic substitutions of the benzylic bromides with potassium fluoride.
Developmental Alterations of Cerebral Gray and White Matter in Children with Congenital Cyanotic Heart Disease
Authors: Leon-Wyss Juan , Rosario Cynthia , Toribio Janet , Speckter Herwin , Foerster Bernd , Oviedo Jairo , Huppertz Hans-Jürgen , Stoeter Peter
Published: August 2018

This article examines the relation between oxygen saturation and T2 star time in cyanotic congenital heart disease and its correlation to cerebral gray and white matter alterations. Magnetic resonance imaging was performed in 25 patients (mean age: 52.2 months) and 32 controls. Gray and white matter volumes, as well as fractional anisotropy and longitudinal diffusivity, were significantly reduced in patients. The reduction longitudinal diffusivity correlated to oxygen saturation and T2 star time of gray matter (p < 0.05). This diffusion tensor imaging (DTI) parameter was most affected in cyanotic congenital heart disease and because is the only parameter showing significant correlation to reduced oxygenation, it should be included more often in the follow-up of these patients over time.
Current Options for the Treatment of Pectus Carinatum: When to Brace and When to Operate?
Authors: Emil Sherif
Published: August 2018

Pectus carinatum has traditionally been described as a rare chest wall anomaly in comparison to pectus excavatum. However, recent data from chest wall anomaly clinics demonstrate that this deformity is probably much more frequent than once believed. In the past, invasive surgical correction by the Ravitch technique was essentially the only option for treatment of pectus carinatum. Major advances over the past two decades have provided additional options, including noninvasive chest wall bracing and minimally invasive surgical correction. This article will discuss current options for the treatment of pectus carinatum, and some of the factors that should be taken into account when choosing the options available. Diagnosis and treatment of the pectus arcuatum variant will also be described.
Patient Reported Outcomes Following Lower Extremity Soft Tissue Sarcoma Resection with Microsurgical Preservation of Ambulation
Authors: MacArthur Ian , McInnes Colin , Dalke Kim , Akra Mohamed , Banerji Shantanu , Buchel Edward , Hayakawa Thomas
Published: August 2018

Background Lower extremity soft tissue sarcoma treatment has evolved from primarily amputation procedures toward limb salvage. This series assesses whether soft tissue sarcoma tissue defects, extensive enough to require microsurgical reconstruction, can reliably result in preservation of ambulation, as well as objectively evaluate functional outcomes utilizing a patient-reported validated scale. It will also look at whether immediate functional muscle reconstructions and tendon transfers can be successful at restoring ambulation, potentially expanding the indications for limb salvage procedures.

Methods A retrospective review of all microsurgical reconstructions for limb salvage in lower extremity sarcoma patients was completed at our institution (2009–2013). Patients were additionally asked to complete the Toronto Extremity Salvage Score(TESS) quality of life survey.

Results Over a 5-year period, 23 patients (mean age: 53 years) underwent free flap reconstructions for 23 sarcomas (mean follow-up: 14 months). Seventy-eight percent of patients received neoadjuvant radiation. The thigh was the most common tumor site (61%) and three muscles were resected on average. Perforator flaps were most frequently used (61%), and functional muscle transfers or immediate tendon transfers were used in four patients. There were no flap take-backs or failures, and 22 patients achieved independent ambulation. Three patients in the series died, two from metastatic disease found postoperatively and one from local recurrence. A 74% response rate was achieved for the TESS survey, with a mean score of 83.

Conclusion Microsurgical reconstruction of lower extremity sarcoma defects enables preservation of independent ambulation. Restoration of function utilizing immediate functional microsurgical reconstructions and tendon transfers should be considered.
Deformities of the Thoracic Wall: Don't Forget the Plastic Surgeon
Authors: Schwabegger Anton
Published: August 2018

Surgical procedures for pectus excavatum (PE) repair, such as minimally invasive repair of pectus excavatum or similar interventions (modified open videoendoscopically assisted repair of pectus excavatum), for remodeling the anterior thoracic wall may finally not always achieve sufficiently pleasing aesthetic results. Particularly in the asymmetric and polymorphic cases, remnant deformities may still be present after any sophisticated remodeling attempt. On the other hand, some cases despite optimal surgical management develop mild recurrences with partial concavity or rib cartilage distortion shortly after pectus-bar removal. Secondary treatment options then may include open access surgery, resection, or reshaping of deformed and prominent costal cartilage. Residual concave areas can be filled by autologous tissue, such as cartilage chips, liposhifting, or implantation of customized alloplastics. To provide the best options for a variety of primary or secondary postsurgical expressions of anterior wall deformities, any physician dealing with PE corrections should be familiar with various shaping and complementary reconstructive techniques or at least should have knowledge of such. However, among treating surgeons, there is an awareness that no single method can be applied for every kind of funnel chest deformity. Careful selection of appropriate techniques, either as a single approach for the ordinary deformities or in conjunction with ancillary procedures for the intricate cases, should be mandatory, based on the heterogeneity of symptoms, severity, expectations, and surgical and technical resources. A variety of such ancillary reconstructive procedures for PE repair are explained and illustrated herewith.
Is the Freedom SOLO Stentless Bioprosthesis a Useful Tool for Patients with Aortic Endocarditis and Aortic Annular Destruction?
Authors: Repossini Alberto , Bacco Lorenzo Di , Gazdag Laszlo , Grubitzsch Herko , Fischlein Theodor , Stara Alessandra , Muneretto Claudio , Santarpino Giuseppe
Published: August 2018

Background The Freedom SOLO (FS) stentless bovine-pericardial prosthesis with a supra-annular implantation technique can be a viable option for patients with endocarditic annular destruction. We assessed early- and long-term outcomes following the use of this prosthesis in extensive aortic valve endocarditis.

Methods From 2006 to 2016, 59 patients with extensive aortic endocarditis underwent aortic valve replacement (AVR) with FS (cumulative follow-up 263 patients-years) in three European centers; all patients presented annular tissue infection, while 54.3% of patients had annular abscess.

Results Mean age was 66 ± 11 years and mean EuroSCORE I was 30.3% (standard deviation: 24.1%). In our series, 30.5% of patients had prosthetic valve endocarditis. Early mortality was 15.2% (nine patients). Estimated overall survival at 5 and 10 years was 68.9% (95% confidence interval [CI]: 62.8–75.0%) and 59.1% (95% CI: 66.8–81.2%), respectively. At 10-year survival, freedom from valve-related death was 83.7% (95% CI: 80.9–86.5%). No structural valve deterioration was reported in this series. Five patients (8.5%) had recurrent endocarditis during follow-up and two of them underwent reoperation. Survival freedom from reoperation and endocarditis at 10-year follow-up was 88.0% (CI: 80.4–95.6%) and 86.7% (CI: 80.5–92.9%), respectively.

Conclusion FS stentless bioprosthesis is a valuable and simple option to achieve AVR in patients with extensive aortic annulus endocarditis. Although in this group of complex patients, early mortality remains considerably high, late survival outcomes are comparable to the more technically demanding homografts and conventional stentless bioprostheses, with low rates of endocarditis recurrence.
Meta-analysis of Valve-in-Valve Transcatheter versus Redo Surgical Aortic Valve Replacement
Authors: Takagi Hisato , Mitta Shohei , Ando Tomo
Published: August 2018

Objective The objective of this study was to determine whether valve-in-valve transcatheter aortic valve implantation (VIV-TAVI) is associated with better survival than redo surgical aortic valve replacement (SAVR) in patients with degenerated aortic valve bioprostheses, and we performed a meta-analysis of comparative studies.

Methods To identify all comparative studies of VIV-TAVI versus redo SAVR; MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched through October 2017. For each study, data regarding all-cause mortality in both the VIV-TAVI and redo SAVR groups were used to generate odds ratios (ORs). To assess selection bias, we generated ORs and (standardized) mean differences (MDs) for baseline characteristics. Study-specific estimates were combined in the random-effects model.

Results Of 446 potentially relevant articles screened initially, 6 reports of retrospective comparative studies enrolling a total of 498 patients were identified. Pooled analyses of baseline characteristics demonstrated no statistically significant differences in the proportion of women, patients with diabetes mellitus, patients with coronary artery disease, and patients with baseline New York Heart Association functional class of ≥III; baseline ejection fraction; and predicted mortality between the VIV-TAVI and redo SAVR groups. Patients in the VIV-TAVI group, however, were significantly older (MD, 4.20 years) and had undergone prior coronary artery bypass grafting more frequently (OR, 2.19) than those in the redo SAVR group. Main pooled analyses demonstrated no statistically significant differences in early (30 days or in-hospital) (OR, 0.91; p = 0.83) and midterm (180 days–3 years) all-cause mortalities (OR, 1.42; p = 0.21) between the VIV-TAVI and redo SAVR groups.

Conclusion In patients with degenerated aortic valve bioprostheses, especially elderly or high-risk patients, VIV-TAVI could be a safe, feasible alternative to redo SAVR. The lack of randomized data and differences in baseline characteristics in the present analysis emphasize the need for prospective randomized trials.
Cardiogenic Necrotizing Enterocolitis: A Clinically Distinct Entity from Classical Necrotizing Enterocolitis
Authors: Siano Elisa , Lauriti Giuseppe , Ceccanti Silvia , Zani Augusto
Published: August 2018

Aim The main purpose of this study was to investigate if necrotizing enterocolitis (NEC) has a different presentation and outcome in patients with congenital heart defect (CHD) (cardiogenic NEC) from those without (classical NEC).

Materials and Methods A systematic review of the literature on the characteristics of infants with NEC and CHD was performed by three independent investigators using a defined strategy (PubMed, Cochrane, Embase, and Web of Science). A meta-analysis was conducted on studies comparing NEC in infants with CHD and non-CHD infants using RevMan 5.3.

Results Systematic review: Of 7,291 abstracts screened, 126 full-text articles were analyzed and 51 studies were included. NEC had an incidence of 5.1% in CHD infants (7,728/151,046, range 0–24%) and 0.8% in non-CHD infants (26,430/3,256,891, range 0.1–8.9%; p < 0.0001). In very low birth weight infants, NEC occurred in 6.3% of CHD patients (6,361/100,454pts) and in 8.9% of non-CHD (23,201/257,794pts; p < 0.0001). In CHD cases, NEC occurred before cardiac surgery in 48% cases and surgery for NEC was required in 31% infants (2,037/6,683). Meta-analysis: In eight comparative studies, the incidence of NEC was higher in CHD infants (6%, 768/13,145) than in infants with no CHD (0.9%, 32,625/3,354,323pts; p < 0.00001, odds ratio [OR] 1.84, 95% confidence interval [CI] 1.7–1.9). The overall mortality was higher in infants with CHD and NEC (38%, 243/640) than in those without CHD (27%, 6651/24810; p < 0.00001, OR 3.4, 95% CI 2.8–4.1).

Conclusion This is the first evidence-based study showing that infants with cardiogenic NEC have different demographics and outcomes than those with classical NEC. The risk of developing NEC and the mortality rate are higher among infants with CHD than in those without. Conversely, the need for intestinal surgery is lower in babies with cardiogenic NEC than in those with classical NEC. Further studies are needed to establish preventative and management interventions that are specific to infants with or at risk of developing cardiogenic NEC.
Modern Neonatal Transport: Sound and Vibration Levels and Their Impact on Physiological Stability
Authors: Bailey Vickie , Cagle Kristi , Kurtz Deborah , Chaaban Hala , Wu Dee , Williams Patricia , Szyld Edgardo
Published: August 2018

Objective To measure sound and vibration in rotary wing air transport (RWAT) and ground ambulance transport (GAT), comparing them to current recommendations, and correlating them with physiological stability measures in transported neonates.

Study Design This is a prospective cohort observational study including infants ≤ 7 days of age transported over an 8-month period. Infants with neurologic conditions were excluded. Sound and vibration was continuously measured during transport. Transport Risk Index of Physiologic Stability (TRIPS) scores were calculated from vital signs as a proxy for physiological stability.

Results In total, 118 newborns were enrolled, of whom 109 were analyzed: 67 in RWAT and 42 in GAT. Peak sound levels ranged from 80.4 to 86.4 dBA in RWAT and from 70.3 to 71.6 dBA in GAT. Whole-body vibration ranged from 1.68 to 5.09 m/s2 in RWAT and from 1.82 to 3.96 m/s2 in GAT. Interval TRIPS scores for each infant were not significantly different despite excessive sound and vibration.

Conclusion Noise levels during neonatal transport exceed published recommendations for both RWAT and GAT and are higher in RWAT. Transported infants are exposed to vibration levels exceeding acceptable adult standards. Despite excessive noise and vibration, levels of physiological stability remained stable after transport in both RWAT and GAT groups.
Muscular-stage Dissection during Far Lateral Approach and Its Transcondylar Extension
Authors: Hirai Sakyo , Obata Yoshiki , Maehara Taketoshi , Aoyagi Masaru , Sato Akihito
Published: August 2018

Background The far lateral approach includes exposure of the C1 transverse process, vertebral artery, posterior arch of the atlas, and occipital condyle. We designed a method for systematic muscular-stage dissection and present our experience with this approach.

Operative Methods We used a horseshoe scalp flap that was reflected downward and medially. The lateral muscle layers were separated layer to layer to expose the suboccipital triangle. The medial muscle layers were separated in the midline and reflected in a single layer. At this stage, the midline of the C1 process and the foramen magnum were identified. The rectus capitis posterior major muscle was reflected to expose the posterior arch of the atlas. The C1 transverse process and vertebral artery were identified by reflection of the superior oblique muscle. The occipital condyle was separated accordingly.

Results We used this method of muscular dissection in 10 patients (foramen magnum meningioma, n = 5; hypoglossal schwannoma, n = 2; others, n = 3). Systematic muscular-stage dissection facilitates identification of the anatomical landmarks with no vertebral artery injury. Gross total removal was obtained in all 9 patients with complex tumors. The patient with vertebral artery dissection successfully underwent proximal clipping.

Conclusion Our muscular-stage dissection could contribute to safe and effective surgery for the far lateral approach.
Indications and Safety of the Zygomatic Osteotomy in Middle Cranial Fossa Surgery: A Retrospective Cohort Review
Authors: Neal Elliot , Pressman Elliot , Athienitis Alexia , Turner Adam , Ma Shunchang , Rao Gautam , Primiani Christopher , Agarwalla Pankaj , van Loveren Harry , Agazzi Siviero
Published: August 2018

Background Zygomatic osteotomy, an adjunct to middle cranial fossa (MCF) surgical approaches, improves the superior-inferior angle of approach and minimizes temporal lobe retraction. However, a decision-making algorithm for selective use of the zygomatic osteotomy and the impact of the zygomatic osteotomy on surgical complications have not been well documented.

Objective We described an algorithm for deciding whether to use a zygomatic osteotomy in MCF surgery and evaluated complications associated with a zygomatic osteotomy.

Methods A retrospective review of MCF cases over 11 years at our academic tertiary referral center was conducted. Demographic variables, tumor characteristics, surgical details, and postoperative complications were extracted.

Results Of the 87 patients included, 15 (17%) received a zygomatic osteotomy. Surgical trajectory oriented from anterior to posterior (A-P) was significantly correlated with the use of the zygomatic osteotomy. Among the cases approached from A-P, we found (receiver-operating characteristic curve) that the cut-off tumor size that predicted a zygomatic osteotomy was 30 mm. Of the 87 cases included, 15 patients had a complication. The multivariate logistic regression model failed to reveal any significant correlation between complications and zygomatic osteotomies.

Conclusions We found that the most important factor determining the use of a zygomatic osteotomy was anticipated trajectory. A-P approaches were most highly correlated with zygomatic osteotomy. Within those cases, a lesion size cut-off of 30 mm was the secondary predicting factor of zygomatic osteotomy use. The odds of suffering a surgical complication were not significantly increased by use of zygomatic osteotomy.
Sinonasal Undifferentiated Carcinoma: A 15-Year Single Institution Experience
Authors: Workman Alan , Brody Robert , Kuan Edward , Baranov Esther , Brooks Steven , Alonso-Basanta Michelle , Newman Jason , Rassekh Christopher , Chalian Ara , Chiu Alexander , Weinstein Gregory , Feldman Michael , Adappa Nithin , O'Malley Bert , Palmer James
Published: August 2018

Objective Sinonasal undifferentiated carcinoma (SNUC) is an aggressive neoplasm, with conflicting existing literature regarding prognosis and treatment due to the rarity of disease. Characterization of optimal SNUC management is necessary for improved outcomes.

Study Design Case series with planned data collection and analysis.

Setting Hospital of the University of Pennsylvania and Pennsylvania Hospital.

Participants Patients with pathologically confirmed SNUC treated within a 15-year period were identified, and records were obtained and evaluated for several demographic characteristics.

Main Outcomes Measures Disease-specific survival from diagnosis was the primary endpoint, while disease recurrence was a secondary endpoint of the study.

Results Twenty-seven patients with established SNUC were included in this cohort, with a median age of 55 years. Eighty-five percent of patients were surgically treated, and 85% of patients presented with stage IV disease. Two-year disease-specific survival was 66% and 5-year disease-specific survival was 46%. Ninety-six percent of patients received both chemotherapy and radiation as adjuvant treatment. Nodal disease at presentation and disease recurrence both significantly decreased patient survival (p < 0.05).

Conclusions The majority of patients at this institution presented with clinically advanced disease, and most were managed with a multimodal approach of surgical resection, chemotherapy, and radiation. Extent of disease at presentation and progression of disease following treatment are poor prognostic signs and may merit a more aggressive approach, while early detection and treatment may improve survival and decrease patient morbidity.
Surgical Intervention for Chronic Mesenteric Ischemia
Authors: Klein Andrea , Bennett Lisa , Ha Cindy , Kirkwood Melissa
Published: August 2018

Symptomatic chronic mesenteric ischemia (CMI) is a relatively rare condition, yet there are significant clinical consequences for those affected by the disease. CMI not only reduces quality of life but also increases an individual's risk for life-threatening acute mesenteric ischemia. Surgery is the definitive treatment to reduce the risk for this potentially fatal outcome, and both endovascular and open surgical strategies are currently utilized. This review article discusses the approach to making a diagnosis of CMI, as well as the surgical techniques used to revascularize the mesenteric circulation.