bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement of voltage deficit of Ge-incorporated kesterite solar cell with 12.3% conversion efficiency
Authors: Kim Shinho , Kim Kang Min , Tampo Hitoshi , Shibata Hajime , Niki Shigeru
Published: September 2016

We demonstrate the improved efficiency of a Cu2Zn(Sn1−

x
Ge
x
)Se4 (CZTGSe) thin-film solar cell with a conversion efficiency of 12.3%; this cell exhibits a greatly improved open-circuit voltage (V
OC) deficit of 0.583 V and a fill factor (FF) of 0.73 compared with previously reported CZTGSe cells. The V
OC deficit was found to be improved through a reduced band tailing via the control of the Ge/(Sn + Se) ratio. In addition, the high FF was mainly induced by a reduced carrier recombination at the absorber/buffer interface and/or in the space charge region, whereas parasitic resistive effects on FF were very small.
Rising atmospheric methane: 2007–2014 growth and isotopic shift
Authors: Nisbet E. G. , Dlugokencky E. J. , Manning M. R. , Lowry D. , Fisher R. E. , France J. L. , Michel S. E. , Miller J. B. , White J. W. C. , Vaughn B. , Bousquet P. , Pyle J. A. , Warwick N. J. , Cain M. , Brownlow R. , Zazzeri G. , Lanoisellé M. , Manning A. C. , Gloor E. , Worthy D. E. J. , Brunke E.‐G. , Labuschagne C. , Wolff E. W. , Ganesan A. L.
Published: September 2016

From 2007 to 2013, the globally averaged mole fraction of methane in the atmosphere increased by 5.7 ± 1.2 ppb yr−1. Simultaneously, δ13CCH4 (a measure of the 13C/12C isotope ratio in methane) has shifted to significantly more negative values since 2007. Growth was extreme in 2014, at 12.5 ± 0.4 ppb, with a further shift to more negative values being observed at most latitudes. The isotopic evidence presented here suggests that the methane rise was dominated by significant increases in biogenic methane emissions, particularly in the tropics, for example, from expansion of tropical wetlands in years with strongly positive rainfall anomalies or emissions from increased agricultural sources such as ruminants and rice paddies. Changes in the removal rate of methane by the OH radical have not been seen in other tracers of atmospheric chemistry and do not appear to explain short‐term variations in methane. Fossil fuel emissions may also have grown, but the sustained shift to more 13C‐depleted values and its significant interannual variability, and the tropical and Southern Hemisphere loci of post‐2007 growth, both indicate that fossil fuel emissions have not been the dominant factor driving the increase. A major cause of increased tropical wetland and tropical agricultural methane emissions, the likely major contributors to growth, may be their responses to meteorological change.
Regional‐scale jet waviness modulates the occurrence of midlatitude weather extremes
Authors: Röthlisberger Matthias , Pfahl Stephan , Martius Olivia
Published: September 2016

Several studies have attributed the occurrence of recent weather extremes to an amplified waviness of the upper tropospheric jet stream. Although trends in jet waviness are still under discussion, it is crucial to better understand the mechanisms through which jet waviness affects weather extremes. Here we show that variations in jet waviness on regional scales effectively modulate the occurrence of daily weather extremes but in regionally different ways. The jet waviness over the North Atlantic and the North Pacific mainly affects where wind, precipitation and cold extremes occur, while a wavy jet over Eurasia strongly favors the occurrence of hot extremes in summer. This is because regional variations of jet waviness are intrinsically linked to the occurrence and tracks of synoptic‐scale weather systems, which can trigger the extremes. We conclude that potential jet waviness changes would affect the occurrence of weather extremes differently depending on where these changes occur.
Comment on “Atmospheric ionization by high‐fluence, hard spectrum solar proton events and their probable appearance in the ice core archive” by A. L. Melott et al.
Authors: Duderstadt K. A. , Dibb J. E. , Jackman C. H. , Randall C. E. , Schwadron N. A. , Solomon S. C. , Spence H. E.
Published: September 2016

Key Points

It is necessary to include preexisting stratospheric HNO3 in an analysis of nitrate deposition from SPEs

SPE‐produced nitrate is negligible compared to the stratospheric background
Investigation on the Manufacture of a Large‐Scale Aluminum Alloy Ingot: Microstructure and Macrosegregation
Authors: Li Ruiqing , Liu Zhilin , Chen Pinghu , Zhong Zhentao , Li Xiaoqian
Published: September 2016

A large‐scale cylindrical 2219 Al alloy ingot (1 250 mm in diameter and 3 300 mm in length) is manufactured using a special DC casting facility. Macrosegregation of major element (Cu) at different casting stages is determined on three cross‐sections of as‐cast ingot. Meanwhile, the evolution of temperature filed in the sump is simulated at different casting stages. Further, the relationships, between macrosegregation, temperature field, and grain structures, are investigated. These work provide some insights in the macrosegregation formation during large‐scale casting or solidification, further promoting to manufacture the large‐scale metallic ingots for potential application.
Electrochemical Intercalation of Potassium into Graphite
Authors: Zhao Jin , Zou Xiaoxi , Zhu Yujie , Xu Yunhua , Wang Chunsheng
Published: September 2016

Exceptional cycling performance of graphite anode in K‐ion batteries is demonstrated with a reversible capacity of 246 mAh g–1 and 89% retention of the initial capacity after 200 cycles. Although the graphite anode experiences huge volume change and worse kinetics during K intercalation/deintercalation, the cycling stability delivered in K‐ion batteries is comparable to that of Li‐ion batteries using the same graphite anode. The combination of excellent electrochemical performance, the abundance and wide availability of K in earth's crust, and the well‐developed technology of the graphite anode make the K‐ion battery very attractive for offering a low cost battery chemistry for large‐scale energy storage applications.
Hyperspectral Imaging Offers Visual and Quantitative Evidence of Drug Release from Zwitterionic‐Phospholipid‐Nanocarbon When Concurrently Tracked in 3D Intracellular Space
Authors: Misra Santosh K. , Ostadhossein Fatemeh , Daza Enrique , Johnson Elyse V. , Pan Dipanjan
Published: September 2016

Spatial and spectral information of a nanocarrier and its payload is crucial for the advancement of luminescence‐based imaging, disease detection, and treatment in complex biological environment. However, it remains challenging to track and quantify the delivery and localization of drugs lacking inherent fluorescence. It is demonstrated that sub 30 nm phospholipid‐stabilized nanoparticles can be detected and quantified using hyperspectral transmitted light microscopy without using a fluorophore. In two proposed model systems, phospholipid‐passivated carbon nanoparticles incorporate the drug in either free form or as a lipid‐based prodrug. Following a rigorous characterization of these nanoparticles, in vitro toxicities via loss in cell growth density and mitochondrial respiration is studied in MCF‐7 breast cancer cells. Furthermore, a detailed inhibitor based study reveals that these particles are internalized based on a clathrin‐mediated pathway, irrespective of the choice of drug formulation. Hyperspectral imaging is performed to obtain the colocalization of carbon nanoparticles and drug molecules intracellularly and can successfully be tracked while therapeutic release is quantified in 3D space. The present work demonstrates that nanoparticles and therapeutic agents can be mapped and measured simultaneously barring the requirement of a dye, thus providing new avenues in the spatiotemporal characterization and synchronous detection and quantification of payload and carrier.
Effective Ligand Engineering of the Cu2ZnSnS4 Nanocrystal Surface for Increasing Hole Transport Efficiency in Perovskite Solar Cells
Authors: Khanzada Laraib Sarfraz , Levchuk Ievgen , Hou Yi , Azimi Hamed , Osvet Andres , Ahmad Rameez , Brandl Marco , Herre Patrick , Distaso Monica , Hock Rainer , Peukert Wolfgang , Batentschuk Miroslaw , Brabec Christoph J.
Published: September 2016

Effective engineering of surface ligands in semiconductor nanocrystals can facilitate the electronic interaction between the individual nanocrystals, making them promising for low‐cost optoelectronic applications. Here, the use of high purity Cu2ZnSnS4 (CZTS) nanocrystals as the photoactive layer and hole‐transporting material is reported in low‐temperature solution‐processed solar cells. The high purity CZTS nanocrystals are prepared by engineering the surface ligands of CZTS nanocrystals, capped originally with the long‐chain organic ligand oleylamine. After ligand removal, CZTS nanocrystals show substantial improvement in photoconductivity and mobility, displaying also an appreciable photoresponse in a simple heterojunction solar cell architecture. More notably, CZTS nanocrystals exhibit excellent hole‐transporting properties as interface layer in perovskite solar cells, yielding power conversion efficiency (PCE) of 15.4% with excellent fill factor (FF) of 81%. These findings underscore the importance of removing undesired surface ligands in nanocrystalline optoelectronic devices, and demonstrate the great potential of CZTS nanocrystals as both active and passive material for the realization of low‐cost efficient solar cells.
High Performance, Multiplexed Lung Cancer Biomarker Detection on a Plasmonic Gold Chip
Authors: Liu Bin , Li Yaling , Wan Hao , Wang Lin , Xu Wei , Zhu Shoujun , Liang Yongye , Zhang Bo , Lou Jiatao , Dai Hongjie , Qian Kun
Published: September 2016

Diagnosis of lung cancer is performed using a plasmonic gold (pGOLD) chip through multiplexed near‐infrared (NIR) detection of carcino‐embryonic antigen (CEA), Cyfra21‐1, and neuron‐specific enolase (NSE) in the serum samples of patients. With ≈50‐fold enhancement of NIR fluorescence, multiplexed microarray analysis of CEA, Cyfra21‐1, and NSE in 10 μL of human serum or whole blood samples on pGOLD chip leads to markedly improved limit‐of‐quantification, limit‐of‐detection, reproducibility, and higher diagnostic sensitivity and specificity compared to traditional biochips and Luminex technology currently in use in hospitals.
Engineering TiO2/Perovskite Planar Heterojunction for Hysteresis‐Less Solar Cells
Authors: Trifiletti Vanira , Manfredi Norberto , Listorti Andrea , Altamura Davide , Giannini Cinzia , Colella Silvia , Gigli Giuseppe , Rizzo Aurora
Published: September 2016

Hybrid halide perovskite solar cells generally show differences in the power output depending on the voltage sweep direction, an undesired phenomenon termed hysteresis. Although the causes of this behavior have not yet been univocally determined, commonly, hysteresis heavily affects solar cells based on flat TiO2 as electron extracting layer. Herein, it is shown how perovskite material quality has a preeminent impact on hysteresis, and how combined deposition and post‐deposition engineered manufacturing could lead to highly efficient and hysteresis‐less solar cells, notwithstanding a planar TiO2‐based layout. This methodology relies on solvent engineering during the casting process, leading to an ultra‐flat, uniform, and thick film ensuring an optimal interface connection with the charge‐extracting layer combined with post‐deposition thermal and vacuum treatments, which merge the crystalline domains and cure the defects at the grain boundaries. This method allows obtaining perovskite active layer with superior optical properties, explaining the ideal device behavior and performances, therefore, a simple optimization of perovskite processing conditions can efficiently stem hysteresis targeting different device layouts. Power conversion efficiency of 15.4% and reduced hysteresis are achieved.
Twist Angle and Rotation Freedom Effects on Luminescent Donor–Acceptor Materials: Crystal Structures, Photophysical Properties, and OLED Application
Authors: Jiang Jianxia , Hu Dehua , Hanif Muddasir , Li Xianglong , Su Shijian , Xie Zengqi , Liu Linlin , Zhang Shitong , Yang Bing , Ma Yuguang
Published: September 2016

The twist angle and rotation freedom between the donor (D) and acceptor (A) in D–A materials plays an important role in their photophysical properties. Here, the authors select the asymmetric acceptor pyridal[2,1,3]thiadiazole (PT) to construct two D–A isomers (p‐TPA‐PT and d‐TPA‐PT) with different twist angle and rotation freedom due to the donor triphenylamine (TPA) proximal or distal to N‐atom (pyridyl), as well as a symmetric bis‐triphenylamine‐substituted compound DTPA‐PT for their investigation. On the basis of experimental and theoretical analysis, the authors have explained how the difference in twist‐angle and freedom of rotation affects the photophysical properties of these materials. The p‐TPA‐PT has small twist angles with a relative large kr, however, the more freedom of rotation of the D–A bond causes larger knr, which is comparable to the kr, and thus a lower photoluminescence (PL) efficiency is obtained in the doped film. Although the d‐TPA‐PT has relative large twist angles with low kr, the suppressed rotation of the DA bond significantly reduces knr, resulting in more competitive kr when compared with the p‐TPA‐PT, consequently relatively higher PL efficiency is observed. The DTPA‐PT, combination of p‐TPA‐PT and d‐TPA‐PT, shows highest kr, much larger than its knr, therefore shows highest PL efficiency. As a result, the DTPA‐PT based organic light emitting diode (OLED) shows beautiful deep‐red emission, maximum external quantum efficiency of 3.87%, Lmax = 12 000 cd m−2, which is among the best deep‐red OLED devices.
Hybrid Perovskite Thin Films as Highly Efficient Luminescent Solar Concentrators
Authors: Nikolaidou Katerina , Sarang Som , Hoffman Christine , Mendewala Benaz , Ishihara Hidetaka , Lu Jennifer Q. , Ilan Boaz , Tung Vincent , Ghosh Sayantani
Published: September 2016

Organic–inorganic hybrid perovskite (PVSK) compounds are at the forefront of photovoltaic research, consistently surpassing silicon solar cells in power conversion efficiency. Possessing high refractive index, broad absorption spectrum, and superior quantum yields, hybrid PVSK thin films are theoretically also ideal candidates for luminescent solar concentrators (LSCs). In practice, however, the possibility of high self‐absorption in a continuous film, coupled with the inherent instability of PVSK materials, have hindered their use in this context. In this work, the viability of hybrid PVSK thin films as the active medium in planar LSCs is investigated. Using spectroscopic and photovoltaic measurements, variation of optical stability and device performance with different lead sources in the PVSK film precursors are monitored. The results display high optical efficiency in the range 15%–29% despite high self‐absorption losses, and the devices remain operational even after seven weeks in ambient conditions. Confirmed by Monte Carlo simulations, the superior performance is attributed to the high quantum yield and refractive index of the PVSKs. These results are encouraging not only for the implementation of PVSK thin films in LSCs, but additionally, for preparation of tandem devices to capture energy escaping as radiative exciton recombination in PVSK solar cells.
Mixed Cation FAxPEA1–xPbI3 with Enhanced Phase and Ambient Stability toward High‐Performance Perovskite Solar Cells
Authors: Li Nan , Zhu Zonglong , Chueh Chu‐Chen , Liu Hongbin , Peng Bo , Petrone Alessio , Li Xiaosong , Wang Liduo , Jen Alex K.‐Y.
Published: September 2016

In this work, different from the commonly explored strategy of incorporating a smaller cation, MA+ and Cs+ into FAPbI3 lattice to improve efficiency and stability, it is revealed that the introduction of phenylethylammonium iodide (PEAI) into FAPbI3 perovksite to form mixed cation FAxPEA1–xPbI3 can effectively enhance both phase and ambient stability of FAPbI3 as well as the resulting performance of the derived devices. From our experimental and theoretical calculation results, it is proposed that the larger PEA cation is capable of assembling on both the lattice surface and grain boundaries to form quais‐3D perovskite structures. The surrounding of PEA+ ions at the crystal grain boundaries not only can serve as molecular locks to tighten FAPbI3 domains but also passivate the surface defects to improve both phase and moisture stablity. Consequently, a high‐performance (PCE:17.7%) and ambient stable FAPbI3 solar cell could be developed.
Motivational Factors for Remaining in or Exiting a Cooperative
Authors: Nilsson Lovisa , Hansson Helena , Lagerkvist Carl Johan
Published: September 2016

Cooperative attributes were incorporated into a push–pull framework to explain exit/remain behavior for dairy farmers delivering to dairy cooperatives. The exit behavior meant establishing a marketing or processing operation in parallel to cooperative deliveries or the planning such an action. Scale development to measure cooperative attributes resulted in six latent variables: A need to restructure the farm business, the membership role in the cooperative, opportunity, fear of negative evaluation, self‐efficacy, and cooperative (dis)loyalty. The latent variables identified were tested against behavioral intentions in two logistic regressions where the dairy farmers’ plans for remaining or exiting the cooperative and their plans for postfarm gate entrepreneurial activities were the dependent variables. Two latent variables emerged as significant predictors: restructuring the farm business and the membership role. These predictors were push factors in the model, suggesting that dissatisfaction with delivery to existing dairy cooperatives, rather than job or life satisfaction from setting up their own business, acted as farmers’ motive to exit. These results can be used in developing communication and strategies for more viable dairy cooperatives and in understanding the incentives behind the ongoing restructuring of the dairy market from a supply perspective. [EconLit citations: Q130, J230, D810].
Hydrocarbon steam reforming using Silicalite‐1 zeolite encapsulated Ni‐based catalyst
Authors: Cimenler Ummuhan , Joseph Babu , Kuhn John N.
Published: September 2016

A Silicalite‐1 zeolite membrane encapsulated 1.6 wt % Ni–1.2 wt % Mg/Ce0.6Zr0.4O2 steam reforming composite catalyst synthesized by a physical coating method was used to investigate effect of encapsulation on size selective steam reforming, using methane (CH4) and toluene (C7H8) as representative species. Characterization methods (scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Physisorption Analysis, and x‐ray diffraction (XRD)) were used to analyze pre‐ and post‐reaction samples. SEM, EDS, and XRD analyses showed that Silicalite‐1 was coated successfully onto the core catalyst. Weisz‐Prater Criteria and Thiele moduli calculations indicated internal diffusion limitations. Combined reforming of CH4 and C7H8 at 800°C on the composite catalyst demonstrated stability during the 10 h time on stream while the uncoated SR catalyst deactivated. The non‐acidic Silicalite‐1 encapsulated catalyst showed decreases (∼2–7%) in both CH4 and C7H8 conversions compared to acidic H‐β zeolite confirming that shell acidity did contribute to conversion and suggested that shell defects/grain boundaries were responsible for the C7H8 conversion. © 2016 American Institute of Chemical Engineers AIChE J, 63: 200–207, 2017
Large‐scale heat exchanger networks synthesis using simulated annealing and the novel rocket fireworks optimization
Authors: Pavão Leandro Vitor , Costa Caliane Bastos Borba , Ravagnani Mauro Antonio da Silva Sá , Jiménez Laureano
Published: September 2016

Heat Exchanger Network (HEN) synthesis is an important field of study in process engineering. However, obtaining optimal HEN design is a complex task. When mathematically formulated, it may require sophisticated methods to achieve good solutions. The complexity increases even more for large‐scale HEN. In this work, a hybrid meta‐heuristic method is presented. A rather simple Simulated Annealing approach is used for the combinatorial level, while a strategy named rocket fireworks optimization is developed and applied to the continuous domain. An advantage over other approaches is that the algorithm was written in C++, which is free and faster when compared to many other languages. The developed method was able to provide the lowest costs solutions reported so far to six cases well studied in the literature. An important feature of the approach here proposed is that, differently from other approaches, it does not split HEN into smaller problems during the optimization. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1582–1601, 2017
Ontogeny of modern human longitudinal body and transverse shoulder proportions
Authors: Frelat Mélanie A. , Coquerelle Michael , Trinkaus Erik
Published: September 2016

Objectives

Whereas variation of modern human adult body size and shape has been widely studied in the context of ecogeographical clines, little is known about the differential growth patterns of transverse and longitudinal dimensions among human populations. Our study explored the ontogenetic variation of those body proportions in modern humans.

Methods

We compared results from four different approaches to study cross‐sectional skeletal samples of Africans (n = 43), Amerindians (n = 69) and Europeans (n = 40) from 0 to 14 years of age. Clavicle, humerus, and femur intermetaphyseal lengths, and femoral distal metaphyseal breadth, were measured. Average ontogenetic trajectories were computed in order to compare the growth patterns of the three groups.

Results

Our findings demonstrated that the three geographical groups shared similar absolute and relative patterns of change with age for the four dimensions considered. Although interpopulation differences existed in transverse to longitudinal as well as in interlimb proportions, those differences did not seem to remain constant throughout ontogeny, similar to what has been shown for intralimb proportions. Growth rates of transverse shoulder proportions differed between populations from different regions after 10 years, whereas those for longitudinal proportions were very similar.

Conclusions

The ontogeny of transverse shoulder proportions is more complex than what is observed for bi‐iliac breadth, suggesting that transverse shoulder to limb proportions are not solely influenced by ecogeographical conditions. Our analysis demonstrates that methodologies that incorporate critical dimensions of body form could shed new light on human adaptation in both paleontological and neontological contexts.
Clinical and genetic aspects of KBG syndrome
Authors: Low Karen , Ashraf Tazeen , Canham Natalie , Clayton‐Smith Jill , Deshpande Charu , Donaldson Alan , Fisher Richard , Flinter Frances , Foulds Nicola , Fryer Alan , Gibson Kate , Hayes Ian , Hills Alison , Holder Susan , Irving Melita , Joss Shelagh , Kivuva Emma , Lachlan Kathryn , Magee Alex , McConnell Vivienne , McEntagart Meriel , Metcalfe Kay , Montgomery Tara , Newbury‐Ecob Ruth , Stewart Fiona , Turnpenny Peter , Vogt Julie , Fitzpatrick David , Williams Maggie ,   DDD Study, Smithson Sarah
Published: September 2016

KBG syndrome is characterized by short stature, distinctive facial features, and developmental/cognitive delay and is caused by mutations in ANKRD11, one of the ankyrin repeat‐containing cofactors. We describe 32 KBG patients aged 2–47 years from 27 families ascertained via two pathways: targeted ANKRD11 sequencing (TS) in a group who had a clinical diagnosis of KBG and whole exome sequencing (ES) in a second group in whom the diagnosis was unknown. Speech delay and learning difficulties were almost universal and variable behavioral problems frequent. Macrodontia of permanent upper central incisors was seen in 85%. Other clinical features included short stature, conductive hearing loss, recurrent middle ear infection, palatal abnormalities, and feeding difficulties. We recognized a new feature of a wide anterior fontanelle with delayed closure in 22%. The subtle facial features of KBG syndrome were recognizable in half the patients. We identified 20 ANKRD11 mutations (18 novel: all truncating) confirmed by Sanger sequencing in 32 patients. Comparison of the two ascertainment groups demonstrated that facial/other typical features were more subtle in the ES group. There were no conclusive phenotype–genotype correlations. Our findings suggest that mutation of ANKRD11 is a common Mendelian cause of developmental delay. Affected patients may not show the characteristic KBG phenotype and the diagnosis is therefore easily missed. We propose updated diagnostic criteria/clinical recommendations for KBG syndrome and suggest that inclusion of ANKRD11 will increase the utility of gene panels designed to investigate developmental delay. © 2016 The Authors. American Journal of Medical Genetics Part A Published by Wiley Periodicals, Inc.
Using a qualitative approach to conceptualize concerns of patients with neurofibromatosis type 1 associated plexiform neurofibromas (pNF) across the lifespan
Authors: Lai Jin‐Shei , Jensen Sally E. , Patel Zabin S. , Listernick Robert , Charrow Joel
Published: September 2016

Neurofibromatosis Type 1 (NF1) plexiform neurofibromas (pNFs) are associated with a variety of symptoms and concerns that affect patients’ quality of life (QOL), highlighting the value of incorporating the patients’ perspective when evaluating treatment outcomes. To better conceptualize the experience of patients with pNFs, this qualitative study sought to identify the most important outcomes to assess from the perspective of patients, families, and clinicians. Clinicians, patients age 5 years old and above, and parents of patients aged 5–17 years participated in semi‐structured interviews to elicit the pNF symptoms/concerns considered most important to assess. The data were analyzed using an iterative coding procedure and the frequency with which symptoms/concerns emerged was tabulated. Eight clinicians, 31 patients, and 17 parents of patients participated in semi‐structured interviews. The most frequently reported concerns raised by patients across all age groups included pain, appearance/disfigurement, social activity/role participation, stigma, and anxiety. For parents, physical functioning was the primary concern, followed by pain, social activity/role participation, appearance/disfigurement, and social relationships. The resulting conceptual framework included five domains to represent the most important identified symptoms/concerns: pain, social functioning, physical function impact, stigma, and emotional distress. This conceptual framework describing the symptoms/concerns of patients with pNF can help investigators create a measurement system to improve assessment of aspects of QOL only patients can report on. It may also provide the ability to identify symptoms/concerns that might warrant referrals to various clinical disciplines. © 2016 Wiley Periodicals, Inc.
Uncommon complications of monochorionic twin pregnancies: Twin reversed arterial perfusion sequence
Authors: Fisher Katie E , Welsh Alec W , Henry Amanda
Published: September 2016

Introduction

Twin reversed arterial perfusion (TRAP) sequence occurs when there is one non‐viable twin without cardiac structures and a viable pump twin that perfuses the acardiac mass. This study aims to investigate the management and immediate neonatal outcomes for monochorionic multiple pregnancies complicated by TRAP referred to the NSW Fetal Therapy Centre (NSW FTC).

Methods

Retrospective cohort study of multiple pregnancies referred to NSW FTC between April 2006 and April 2014, reviewing data for cases of TRAP sequence (n = 19, including two triplet cases) compared to a timeframe matched sample of uncomplicated monochorionic diamniotic (MCDA) twin pregnancies managed in the unit (n = 45).

Results

Primary management of the 19 TRAP cases was expectant management in 10 (53%), radiofrequency ablation (RFA) in 6 (32%), and bipolar cord coagulation, amniodrainage and termination of pregnancy in 1 case each. 1 of 6 RFA cases had pump twin demise <1 week post‐procedure. Average gestation at birth (35.1 ± 5.0 vs. 35.0 ± 2.8 weeks) and mean birthweight (2157 ± 1019 g vs. 2245 ± 537 g) were similar between TRAP pump fetuses and uncomplicated MCDA cases. Pump twin survival was 81% (twins only) compared to 98% for uncomplicated MCDA twins (P = 0.02), and in 5 of 19 (26%) TRAP pregnancies the pump fetus had a congenital anomaly.

Conclusion

Mean gestational age at birth and mean birthweight were similar for both TRAP and uncomplicated MCDA pregnancies. TRAP cases, however, had higher perinatal mortality, and high rates of congenital anomaly. The overall neonatal outcome at NSW FTC for TRAP cases is similar to reported international outcomes.
Reply to “Comment on ‘Super‐resolution microscopy by movable thin‐films with embedded microspheres: Resolution analysis’ [Ann. Phys. (Berlin) 527, 513 (2015)]”
Authors: Allen Kenneth W. , Li Yangcheng , Astratov Vasily N.
Published: September 2016

In a comment [A. Darafsheh, Ann. Phys. (Berlin) 528 (2016)] on our paper [K. W. Allen et al., Ann. Phys. (Berlin) 527, 513–522 (2015)], the results and conclusions of our work were doubted along two directions. The first is related to the methodology of our resolution quantification and use of confocal microscopy. The second is related to the mathematical treatment of our magnification measurements aimed at estimating the gap between the microsphere and the object which is relevant to the mechanisms of super‐resolution imaging. We explain that both our estimates of the object resolution and gap are valid. The comment brings out points that are of rather secondary relevance, does not offer a worthwhile improvement of the mathematical treatment, and misrepresents our estimation procedure for the gap size. We also discuss general factors and problems involved in the quantification of resolution in microsphere‐assisted microscopy.

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Discovery of a Superconducting Cu–Bi Intermetallic Compound by High‐Pressure Synthesis
Authors: Clarke Samantha M. , Walsh James P. S. , Amsler Maximilian , Malliakas Christos D. , Yu Tony , Goedecker Stefan , Wang Yanbin , Wolverton Chris , Freedman Danna E.
Published: September 2016

A new intermetallic compound, the first to be structurally identified in the Cu−Bi binary system, is reported. This compound is accessed by high‐pressure reaction of the elements. Its detailed characterization, physical property measurements, and ab initio calculations are described. The commensurate crystal structure of Cu11Bi7 is a unique variation of the NiAs structure type. Temperature‐dependent electrical resistivity and heat capacity measurements reveal a bulk superconducting transition at Tc=1.36 K. Density functional theory calculations further demonstrate that Cu11Bi7 can be stabilized (relative to decomposition into the elements) at high pressure and temperature. These results highlight the ability of high‐pressure syntheses to allow for inroads into heretofore‐undiscovered intermetallic systems for which no thermodynamically stable binaries are known.
A Programmable Signaling Molecular Recognition Nanocavity Prepared by Molecular Imprinting and Post‐Imprinting Modifications
Authors: Horikawa Ryo , Sunayama Hirobumi , Kitayama Yukiya , Takano Eri , Takeuchi Toshifumi
Published: September 2016

Inspired by biosystems, a process is proposed for preparing next‐generation artificial polymer receptors with molecular recognition abilities capable of programmable site‐directed modification following construction of nanocavities to provide multi‐functionality. The proposed strategy involves strictly regulated multi‐step chemical modifications: 1) fabrication of scaffolds by molecular imprinting for use as molecular recognition fields possessing reactive sites for further modifications at pre‐determined positions, and 2) conjugation of appropriate functional groups with the reactive sites by post‐imprinting modifications to develop programmed functionalizations designed prior to polymerization, allowing independent introduction of multiple functional groups. The proposed strategy holds promise as a reliable, affordable, and versatile approach, facilitating the emergence of polymer‐based artificial antibodies bearing desirable functions that are beyond those of natural antibodies.
Difference between Extra‐ and Intracellular T1 Values of Carboxylic Acids Affects the Quantitative Analysis of Cellular Kinetics by Hyperpolarized NMR
Authors: Karlsson Magnus , Jensen Pernille Rose , Ardenkjær‐Larsen Jan Henrik , Lerche Mathilde H.
Published: September 2016

Incomplete knowledge of the longitudinal relaxation time constant (T1) leads to incorrect assumptions in quantitative kinetic models of cellular systems, studied by hyperpolarized real‐time NMR. Using an assay that measures the intracellular signal of small carboxylic acids in living cells, the intracellular T1 of the carboxylic acid moiety of acetate, keto‐isocaproate, pyruvate, and butyrate was determined. The intracellular T1 is shown to be up to four‐fold shorter than the extracellular T1. Such a large difference in T1 values between the inside and the outside of the cell has significant influence on the quantification of intracellular metabolic activity. It is expected that the significantly shorter T1 value of the carboxylic moieties inside cells is a result of macromolecular crowding. An artificial cytosol has been prepared and applied to predict the T1 of other carboxylic acids. We demonstrate the value of this prediction tool.
Electron Delocalization in Perylene Diimide Helicenes
Authors: Schuster Nathaniel J. , Paley Daniel W. , Jockusch Steffen , Ng Fay , Steigerwald Michael L. , Nuckolls Colin
Published: September 2016

We report two new helicenes derived from the double fusion of an acene with two perylene diimide (PDI) subunits. These PDI‐helicene homologs exhibit very different structural and electronic properties, despite differing by only a single ring in the link between the PDI units. The shorter inter‐PDI link brings the two PDI subunits closer together, and this results in the collision of their respective π‐electron clouds. This collision facilitates intramolecular through‐space electronic delocalization when the PDI‐helicene is reduced.
Discovery of a Mosaic‐Like Biosynthetic Assembly Line with a Decarboxylative Off‐Loading Mechanism through a Combination of Genome Mining and Imaging
Authors: Mir Mohseni Mahsa , Höver Thomas , Barra Lena , Kaiser Marcel , Dorrestein Pieter C. , Dickschat Jeroen S. , Schäberle Till F.
Published: September 2016

The biosynthetic gene cluster for the antiplasmodial natural product siphonazole was identified by using a combination of genome mining, imaging, and expression studies in the natural producer Herpetosiphon sp. B060. The siphonazole backbone is assembled from an unusual starter unit from the shikimate pathway that is extended by the action of polyketide synthases and non‐ribosomal peptide synthetases with unusual domain structures, including several split modules and a large number of duplicated domains and domains predicted to be inactive. Product release proceeds through decarboxylation and dehydration independent of the thioesterase SphJ and yields the diene terminus of siphonazole. High variation in terms of codon‐usage within the gene cluster, together with the dislocated domain organization, suggest a recent emergence in evolutionary terms.
Electrophilic RNA for Peptidyl‐RNA Synthesis and Site‐Specific Cross‐Linking with tRNA‐Binding Enzymes
Authors: Fonvielle Matthieu , Sakkas Nicolas , Iannazzo Laura , Le Fournis Chloé , Patin Delphine , Mengin‐Lecreulx Dominique , El‐Sagheer Afaf , Braud Emmanuelle , Cardon Sébastien , Brown Tom , Arthur Michel , Etheve‐Quelquejeu Mélanie
Published: September 2016

RNA functionalization is challenging due to the instability of RNA and the limited range of available enzymatic reactions. We developed a strategy based on solid phase synthesis and post‐functionalization to introduce an electrophilic site at the 3′ end of tRNA analogues. The squarate diester used as an electrophile enabled sequential amidation and provided asymmetric squaramides with high selectivity. The squaramate‐RNAs specifically reacted with the lysine of UDP‐MurNAc‐pentapeptide, a peptidoglycan precursor used by the aminoacyl‐transferase FemXWv for synthesis of the bacterial cell wall. The peptidyl‐RNA obtained with squaramate‐RNA and unprotected UDP‐MurNAc‐pentapeptide efficiently inhibited FemXWv. The squaramate unit also promoted specific cross‐linking of RNA to the catalytic Lys of FemXWv but not to related transferases recognizing different aminoacyl‐tRNAs. Thus, squaramate‐RNAs provide specificity for cross‐linking with defined groups in complex biomolecules due to its unique reactivity.
One‐Step Microfluidic Fabrication of Polyelectrolyte Microcapsules in Aqueous Conditions for Protein Release
Authors: Zhang Liyuan , Cai Li‐Heng , Lienemann Philipp S. , Rossow Torsten , Polenz Ingmar , Vallmajo‐Martin Queralt , Ehrbar Martin , Na Hui , Mooney David J. , Weitz David A.
Published: September 2016

We report a microfluidic approach for one‐step fabrication of polyelectrolyte microcapsules in aqueous conditions. Using two immiscible aqueous polymer solutions, we generate transient water‐in‐water‐in‐water double emulsion droplets and use them as templates to fabricate polyelectrolyte microcapsules. The capsule shell is formed by the complexation of oppositely charged polyelectrolytes at the immiscible interface. We find that attractive electrostatic interactions can significantly prolong the release of charged molecules. Moreover, we demonstrate the application of these microcapsules in encapsulation and release of proteins without impairing their biological activities. Our platform should benefit a wide range of applications that require encapsulation and sustained release of molecules in aqueous environments.
Mirror‐Image Packing Provides a Molecular Basis for the Nanomolar Equipotency of Enantiomers of an Experimental Herbicide
Authors: Bisson Claudine , Britton K. Linda , Sedelnikova Svetlana E. , Rodgers H. Fiona , Eadsforth Thomas C. , Viner Russell C. , Hawkes Tim R. , Baker Patrick J. , Rice David W.
Published: September 2016

Programs of drug discovery generally exploit one enantiomer of a chiral compound for lead development following the principle that enantiomer recognition is central to biological specificity. However, chiral promiscuity has been identified for a number of enzyme families, which have shown that mirror‐image packing can enable opposite enantiomers to be accommodated in an enzyme's active site. Reported here is a series of crystallographic studies of complexes between an enzyme and a potent experimental herbicide whose chiral center forms an essential part of the inhibitor pharmacophore. Initial studies with a racemate at 1.85 Å resolution failed to identify the chirality of the bound inhibitor, however, by extending the resolution to 1.1 Å and by analyzing high‐resolution complexes with the enantiopure compounds, we determined that both enantiomers make equivalent pseudosymmetric interactions in the active site, thus mimicking an achiral reaction intermediate.
Lessons from 1,3‐Hydride Shifts in Sesquiterpene Cyclizations
Authors: Rinkel Jan , Rabe Patrick , Garbeva Paolina , Dickschat Jeroen S.
Published: September 2016

Stereospecifically labelled precursors were subjected to conversion by seven bacterial sesquiterpene cyclases to investigate the stereochemistry of their initial 1,10‐cyclisation‐1,3‐hydride shift cascades. Enzymes with products of known absolute configuration showed a coherent stereochemical course, except for (−)‐α‐amorphene synthase, for which the obtained results are better explained by an initial 1,6‐cyclisation. The link between the absolute configuration of the product and the stereochemical course of the 1,3‐hydride shifts enabled assignment of the absolute configurations of three enzyme products, which were confirmed independently through the absolute configuration of the common byproduct germacrene D‐4‐ol.
A Macrocyclic Ruthenium(III) Complex Inhibits Angiogenesis with Down‐Regulation of Vascular Endothelial Growth Factor Receptor‐2 and Suppresses Tumor Growth In Vivo
Authors: Kwong Wai‐Lun , Lam Kar‐Yee , Lok Chun‐Nam , Lai Yau‐Tsz , Lee Pui‐Yan , Che Chi‐Ming
Published: September 2016

A macrocyclic ruthenium(III) complex [RuIII(N2O2)Cl2]Cl (Ru‐1) is reported as an inhibitor of angiogenesis and an anti‐tumor compound. The complex is relatively non‐cytotoxic towards endothelial and cancer cell lines in vitro, but specifically inhibited the processes of angiogenic endothelial cell tube formation and cancer cell invasion. Moreover, compared with known anti‐cancer ruthenium complexes, Ru‐1 is distinct in that it suppressed the expression of vascular endothelial growth factor receptor‐2 (VEGFR2), and the associated downstream signaling that is crucial to tumor angiogenesis. In addition, in vivo studies showed that Ru‐1 inhibited angiogenesis in a zebrafish model and suppressed tumor growth in nude mice bearing cancer xenografts.
Enantioselective Pd‐Catalyzed Allylic Alkylation Reactions of Dihydropyrido[1,2‐a]indolone Substrates: Efficient Syntheses of (−)‐Goniomitine, (+)‐Aspidospermidine, and (−)‐Quebrachamine
Authors: Pritchett Beau P. , Kikuchi Jun , Numajiri Yoshitaka , Stoltz Brian M.
Published: September 2016

The successful application of dihydropyrido[1,2‐a]indolone (DHPI) substrates in Pd‐catalyzed asymmetric allylic alkylation chemistry facilitates rapid access to multiple alkaloid frameworks in an enantioselective fashion. Strategic bromination at the indole C3 position greatly improved the allylic alkylation chemistry and enabled a highly efficient Negishi cross‐coupling downstream. The first catalytic enantioselective total synthesis of (−)‐goniomitine, along with divergent formal syntheses of (+)‐aspidospermidine and (−)‐quebrachamine, are reported herein.
Preparation and characterization of cellulose triacetate membranes via thermally induced phase separation
Authors: Yu Yuan , Wu Qing‐Yun , Liang Hong‐Qing , Gu Lin , Xu Zhi‐Kang
Published: September 2016

A series of cellulose triacetate (CTA) membranes were prepared via thermally induced phase separation (TIPS) process with dimethyl sulfone (DMSO2) and polyethylene glycol (PEG400) as a crystallizable diluent and an additive, respectively. The phase separation behavior of CTA/DMSO2/PEG400 ternary system was investigated in detail by optical microscopy, differential scanning calorimetry and wide angle X‐ray diffraction. This ternary system dynamically undergoes solid‐solid phase separation and thus the CTA membranes possess cellular, lacy, plate‐, or even ellipse‐shaped pores. However, we can modulate the pore structure, porosity, water flux, and mechanical properties of the membranes by varying polymer concentration, composition of the mixed diluent, and cooling condition. Due to the intrinsic hydrophilicity, the prepared CTA membranes have better antifouling property than polysulfone membranes. These porous membranes were used as supports to fabricate thin‐film composite forward osmosis (FO) membranes, which show good water permeability and selectivity. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2017,134, 44454.
Metal/Graphitic Carbon Nitride Composites: Synthesis, Structures, and Applications
Authors: Wang Luona , Wang Chengyin , Hu Xiaoya , Xue Huaiguo , Pang Huan
Published: September 2016

Graphitic carbon nitride (g‐C3N4) has been widely used in fields related to energy and materials science. However, nanostructured g‐C3N4 photocatalysts synthesized by traditional thermal polycondensation methods have the disadvantage of small specific surface areas and wide band gaps; these limit the catalytic activity and application range of g‐C3N4. Based on the unique nanostructure of g‐C3N4, it is a feasible method to modify g‐C3N4 with metals to design novel metal–semiconductor composites. Metals alter the photochemical properties of g‐C3N4, in particular, narrow the band gap and expand photoabsorption into the visible range, which improves the photocatalytic performance. This review covers recent progress in metal/g‐C3N4 nanocomposites for photocatalysts, organic systems, biosensors, and so on. The aim is to summarize the synthetic methods, nanostructures, and applications of metal/g‐C3N4 nanocomposite materials, as well as discuss future research directions in these areas.
Acid‐Base Switchable [2]‐ and [3]Rotaxane Molecular Shuttles with Benzimidazolium and Bis(pyridinium) Recognition Sites
Authors: Zhu Kelong , Vukotic V. Nicholas , Loeb Stephen J.
Published: September 2016

For the purpose of developing higher level mechanically interlocked molecules (MIMs), such as molecular switches and machines, a new rotaxane system was designed in which both the 1,2‐bis(pyridinium)ethane and benzimidazolium recognition templating motifs were combined. These two very different recognition sites were successfully incorporated into [2]rotaxane and [3]rotaxane molecular shuttles which were fully characterized by 1H NMR, 2D EXSY, single‐crystal X‐ray diffraction and VT NMR analysis. By utilizing benzimidazolium as both a recognition site and stoppering group it was possible to create not only an acid/base switchable [2]rotaxane molecular shuttle (energy barrier 20.9 kcal⋅mol−1) but also a [3]rotaxane molecular shuttle that displays unique dynamic behavior involving the simultaneous motion of two macrocyclic wheels on a single dumbbell. This study provides new insights into the design of switchable molecular shuttles. Due to the unique properties of benzimidazoles, such as fluorescence and metal coordination, this new type of molecular shuttle may find further applications in developing functional molecular machines and materials.
A GIS‐based model to estimate citrus pulp availability for biogas production: an application to a region of the Mediterranean Basin
Authors: Valenti Francesca , Porto Simona MC , Chinnici Gaetano , Cascone Giovanni , Arcidiacono Claudia
Published: September 2016

In recent years, biogas from biomasses has increasingly been considered a feasible alternative to energy from fossil fuel. The utilization of biomasses obtained from citrus processing for juice extraction is being investigated for energy purposes, as a biofuel or organic matrix for bioethanol or biogas extraction, besides for the extraction of high added‐value by‐products and animal feed. In citrus producing areas, uncertainty often exists as to the amount of processed product and, therefore, correct planning of the use of ‘citrus pulp’ for energy purposes has not yet been carried out.

The objective of this study was to analyze the spatial distribution of the citrus fruit production area and the amount of processed citrus in order to quantify the citrus pulp available for biogas production. It could contribute to build an information base suitable for multi‐criteria analysis aimed at finding optimal locations for biogas plants and increasing their number in a territory. The GIS‐based methodology, which was applied to the case study of citrus pulp production in Sicily, included official statistics data and information derived from specific surveys and the computation of indicators regarding citrus‐producing areas, citrus production, processed production, and the amount of citrus pulp obtained. The results showed that the index that describes the level of availability of citrus pulp for biogas production is suitable to provide information on the potential production of citrus pulp in the different areas of the whole territory analyzed. Furthermore, the total amount of available citrus pulp corresponded theoretically to 15,204,775.8 Nm3 biogas. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd