bluuebunny/crossref_metadata_2025 huggingface dataset:
Switching Off Hysteresis in Perovskite Solar Cells by Fine‐Tuning Energy Levels of Extraction Layers
Authors: Guerrero Antonio , Bou Agustín , Matt Gebhard , Almora Osbel , Heumüller Thomas , Garcia‐Belmonte Germà , Bisquert Juan , Hou Yi , Brabec Christoph
Published: April 2018

Lead halide perovskites often suffer from a strong hysteretic behavior on their j–V response in photovoltaic devices that has been correlated with slow ion migration. The electron extraction layer has frequently been pointed to as the main culprit for the observed hysteretic behavior. In this work three hole transport layers are studied with well‐defined highest occupied molecular orbital (HOMO) levels and interestingly the hysteretic behavior is markedly different. Here it is shown that an adequate energy level alignment between the HOMO level of the extraction layer and the valence band of the perovskite, not only suppresses the hysteresis, avoiding charge accumulation at the interfaces, but also degradation of the hole transport layer is reduced. Numerical simulation suggests that formation of an injection barrier at the organic/perovskite heterointerface could be one mechanism causing hysteresis. The suppression of such barriers may require novel design rules for interface materials. Overall, this work highlights that both external contacts need to be carefully optimized in order to obtain hysteresis‐free perovskite devices.
Design Strategies, Practical Considerations, and New Solution Processes of Sulfide Solid Electrolytes for All‐Solid‐State Batteries
Authors: Park Kern Ho , Bai Qiang , Kim Dong Hyeon , Oh Dae Yang , Zhu Yizhou , Mo Yifei , Jung Yoon Seok
Published: April 2018

Owing to the ever‐increasing safety concerns about conventional lithium‐ion batteries, whose applications have expanded to include electric vehicles and grid‐scale energy storage, batteries with solidified electrolytes that utilize nonflammable inorganic materials are attracting considerable attention. In particular, owing to their superionic conductivities (as high as ≈10−2 S cm−1) and deformability, sulfide materials as the solid electrolytes (SEs) are considered the enabling material for high‐energy bulk‐type all‐solid‐state batteries. Herein the authors provide a brief review on recent progress in sulfide Li‐ and Na‐ion SEs for all‐solid‐state batteries. After the basic principles in designing SEs are considered, the experimental exploration of multicomponent systems and ab initio calculations that accelerate the search for stronger candidates are discussed. Next, other issues and challenges that are critical for practical applications, such as instability in air, electrochemical stability, and compatibility with active materials, are discussed. Then, an emerging progress in liquid‐phase synthesis and solution process of SEs and its relevant prospects in ensuring intimate ionic contacts and fabricating sheet‐type electrodes is highlighted. Finally, an outlook on the future research directions for all‐solid‐state batteries employing sulfide superionic conductors is provided.
Convergent Assembly of Enantioenriched Tetrahydrobenzofuro[2,3‐b]pyrrole Scaffolds by AgI‐Catalyzed Asymmetric Domino Reaction of Isocyanoacetates
Authors: Cheng Hengguang , Zhang Runmei , Wang Min , Zeng Xiaofei , Xie Chunsong
Published: April 2018

In the presence of cinchona‐derived chiral phosphine ligands, enantioenriched tetrahydrobenzofuro[2,3‐b]pyrroles can be efficiently assembled by a mild, convergent and atom‐economic AgI‐catalyzed asymmetric domino reaction of readily available isocyanoacetates and 2‐(2‐hydroxyphenyl)acrylates.
How to perform an ultrasound to diagnose endometriosis
Authors: Leonardi Mathew , Condous George
Published: April 2018

Ultrasound has become an invaluable tool for the workup and management of patients with symptoms and signs of endometriosis. Until the publication on the systematic approach to ultrasound in patients with suspected endometriosis by the International Deep Endometriosis Analysis (IDEA) group, there was significant heterogeneity in the scientific literature in nomenclature, definitions and components of this particular scan. Despite the concise four steps outlined in their consensus statement, the nature of this ultrasound is advanced, complex and time consuming. Without intending to oversimplify the task, we propose a practical and comprehensive approach on how to perform an ultrasound scan to assess the pelvis of a woman with potential underlying endometriosis.
Enhancing the Anti‐Solvatochromic Two‐Photon Fluorescence for Cirrhosis Imaging by Forming a Hydrogen‐Bond Network
Authors: Ren Tian‐Bing , Xu Wang , Zhang Qian‐Ling , Zhang Xing‐Xing , Wen Si‐Yu , Yi Hai‐Bo , Yuan Lin , Zhang Xiao‐Bing
Published: April 2018

Two‐photon imaging is an emerging tool for biomedical research and clinical diagnostics. Electron donor–acceptor (D–A) type molecules are the most widely employed two‐photon scaffolds. However, current D–A type fluorophores suffer from solvatochromic quenching in aqueous biological samples. To address this issue, we devised a novel class of D–A type green fluorescent protein (GFP) chromophore analogues that form a hydrogen‐bond network in water to improve the two‐photon efficiency. Our design results in two‐photon chalcone (TPC) dyes with 0.80 quantum yield and large two‐photon action cross section (210 GM) in water. This strategy to form hydrogen bonds can be generalized to design two‐photon materials with anti‐solvatochromic fluorescence. To demonstrate the improved in vivo imaging, we designed a sulfide probe based on TPC dyes and monitored endogenous H2S generation and scavenging in the cirrhotic rat liver for the first time.
The Contribution of Pyroelectricity of AgI Crystals to Ice Nucleation
Authors: Curland Sofia , Meirzadeh Elena , Cohen Hagai , Ehre David , Maier Joachim , Lahav Meir , Lubomirsky Igor
Published: April 2018

The pyroelectricity of AgI crystals strongly affects the icing temperature of super‐cooled water, as disentangled from that of epitaxy. This deduction was achieved by the design of polar crystalline ceramic pellets of AgI, with experimentally determined sense of polarity. These pellets are suitable for measuring both their pyroelectric properties as well as the icing temperature of super‐cooled water, separately on each of the expressed Ag+ and I− hemihedral surfaces. The positive pyroelectric charge at the silver‐enriched side elevates the icing temperature, whereas the negative charge at the iodide side decreases that temperature. Moreover, the effect of pyroelectric charge remains dominant despite the presence of contaminants on both the silver and the iodide‐enriched surfaces. Consequently an electrochemical process for ice nucleation is suggested, which might be of relevance for understanding the role played by electric charges in heterogeneous icing processes in general.
Preparation of Swellable Hydrogel‐Containing Colloidosomes from Aqueous Two‐Phase Pickering Emulsion Droplets
Authors: Douliez Jean‐Paul , Martin Nicolas , Beneyton Thomas , Eloi Jean‐Charles , Chapel Jean‐Paul , Navailles Laurence , Baret Jean‐Christophe , Mann Stephen , Béven Laure
Published: April 2018

The fabrication of stable colloidosomes derived from water‐in‐water Pickering‐like emulsions are described that were produced by addition of fluorescent amine‐modified polystyrene latex beads to an aqueous two‐phase system consisting of dextran‐enriched droplets dispersed in a PEG‐enriched continuous phase. Addition of polyacrylic acid followed by carbodiimide‐induced crosslinking with dextran produces hydrogelled droplets capable of reversible swelling and selective molecular uptake and exclusion. Colloidosomes produced specifically in all‐water systems could offer new opportunities in microencapsulation and the bottom‐up construction of synthetic protocells.
Cu[B2(SO4)4] und Cu[B(SO4)2(HSO4)] – zwei silicatanaloge Borosulfate unterschiedlicher Dimensionalität: Vergleich von Stabilität und Azidität
Authors: Bruns Jörn , Podewitz Maren , Liedl Klaus R. , Janka Oliver , Pöttgen Rainer , Huppertz Hubert
Published: April 2018

Borosulfate repräsentieren eine stetig wachsende Verbindungsklasse, deren strukturelle und chemische Vielfalt noch nicht absehbar ist. In dieser Zuschrift berichten wir über die ersten zwei Borosulfate des Kupfers, Cu[B2(SO4)4] und Cu[B(SO4)2(HSO4)]. Diese sind strukturell verwandt, unterscheiden sich aber in der Dimensionalität ihrer anionischen Substruktur. Cu[B2(SO4)4] weist anionische Ketten entsprechend der Formel
[B(SO4)4/2]− auf, die sowohl eine Twist‐ als auch eine einzigartige Sessel‐Konformation der B(SO4)2B‐Einheiten zeigen. In Cu[B(SO4)2(HSO4)] hingegen werden komplexe Oxoanionen der Formel [B2(SO4)4(HSO4)2]4− gefunden, für die ausschließlich eine Twist‐Konformation realisiert wird. Bildhaft kann das komplexe Anion als protonierter Ausschnitt aus der anionischen Kette betrachtet werden. Vergleichende DFT‐Studien, basierend auf magnetochemischen Messungen, ergänzen die experimentellen Ergebnisse. Berechnungen der pKs‐Werte der beiden Konformere des Anions [B2(SO4)4(HSO4)2]4− ergeben, dass diese eher mit denen der Kieselsäure als mit denen der Schwefelsäure vergleichbar sind, was die nahe Verwandtschaft der Borosulfate zu Silicaten unterstreicht.
A Crystalline Diazadiborinine Radical Cation and Its Boron‐Centered Radical Reactivity
Authors: Wang Baolin , Li Yongxin , Ganguly Rakesh , Webster Richard D. , Kinjo Rei
Published: April 2018

One‐electron oxidation of 1,4,2,5‐diazadiborinine 1 has been studied. While the reaction of 1 a bearing phenyl groups on the B atoms with AgAl{OC(CF3)3}4 afforded a complex mixture, the same oxidation reaction with 1 b featuring bulky mesityl substituents on the B atoms rendered the corresponding cation radical 2 b as an isolable species. X‐ray diffraction analysis, EPR spectroscopy, and DFT calculations of 2 b revealed the delocalization of the unpaired electron over the entire π‐system of 2 b, as well as a large spin density (0.76 in total) on the two equivalent boron atoms. The chemical trapping reaction of 2 b with p‐benzoquinone and triphenyltin hydride afforded the dicationic species 3 containing two newly formed B−O bonds and the monocationic product 2b‐H containing a B−H bond, respectively, thus confirming the boron‐centered radical reactivity of 2 b.
Aggregation of Giant Cerium–Bismuth Tungstate Clusters into a 3D Porous Framework with High Proton Conductivity
Authors: Liu Jian‐Cai , Han Qing , Chen Li‐Juan , Zhao Jun‐Wei , Streb Carsten , Song Yu‐Fei
Published: April 2018

The exploration of high nuclearity molecular metal oxide clusters and their reactivity is a challenge for chemistry and materials science. Herein, we report an unprecedented giant molecular cerium–bismuth tungstate superstructure formed by self‐assembly from simple metal oxide precursors in aqueous solution. The compound, {[W14CeIV6O61]([W3Bi6CeIII3(H2O)3O14][B‐α‐BiW9O33]3)2}34− was identified by single‐crystal X‐ray diffraction and features 104 metal centers, a relative molar mass of ca. 24 000 and is ca. 3.0×2.0×1.7 nm3 in size. The cluster anion is assembled around a central {Ce6} octahedron which is stabilized by several molecular metal oxide shells. Six trilacunary Keggin anions ([B‐α‐BiW9O33]9−) cap the superstructure and limit its growth. In the crystal lattice, water‐filled channels with diameters of ca. 0.5 nm are observed, and electrochemical impedance spectroscopy shows pronounced proton conductivity even at low temperature.
Berylliumkomplexe mit biologisch relevanten funktionellen Gruppen: Koordinationsgeometrien und Bindungsaffinitäten
Authors: Müller Matthias , Buchner Magnus R.
Published: April 2018

Sowohl der Koordinationsmodus des Berylliumatoms innerhalb eines Proteins als auch die Bindungsaffinität von Beryllium für Peptide sind unbekannt, da bislang keine koordinationschemischen Untersuchungen zu biologisch relevanten funktionellen Gruppen durchgeführt wurden. Hier werden die ersten umfassenden Untersuchungen zu einzähnigen Carboxylaten, Estern, Aldehyden und Alkoholen vorgestellt. Die Bindungsaffinitäten des Be2+‐Kations für die untersuchten funktionellen Gruppen wurden in Lösung und im Festkörper analysiert und lassen sich wie folgt einordnen: Carboxylat>Alkohol>Aldehyd>Ester. Von allen untersuchten Koordinationsverbindungen wurden Einkristallstrukturen erhalten, auch für das nicht‐basische Berylliumbenzoat, dessen Molekülstruktur aus einem unerwarteten, zwölfkernigen Makrocyclus besteht und welches das bislang erste Beispiel dieser Berylliumcarboxylate darstellt. Die Ergebnisse ermöglichen es, potenzielle Bindungsstellen für Be2+‐Kationen innerhalb eines Proteins zu evaluieren, was für das Verständnis des Mechanismus metallinduzierter Immunreaktionen nötig ist.
Photochemical Generation of Chiral N,B,X‐Heterocycles by Heteroaromatic C−X Bond Scission (X=S, O) and Boron Insertion
Authors: Mellerup Soren K. , Li Cally , Radtke Julian , Wang Xiang , Li Quan‐Song , Wang Suning
Published: April 2018

Chiral organoboron compounds with a chelate backbone and mesityl/heterocycle substituents (thienyl, furyl, and derivatives thereof) undergo a quantitative phototransformation that yields rare, chiral N,B,X‐containing heterocycles, such as base‐stabilized 1,2‐thiaborinines and 1,2‐oxaborinines. Boriranes were observed as intermediates in some of these transformations. The oxaborinines display further reactivity, generating 4a,12b‐dihydrobenzo[h][1,2]oxaborinino[4,3‐f]quinolines through a sequential conrotatory electrocyclization and a [1,5]‐H shift. The N,B,X‐containing heterocycles display strong blue‐green to orange‐red emission in the solid state. Combined DFT//CASP2T calculations suggest that a common biradical intermediate is responsible for the formation of these compounds as well as their interconversion.
Universal pH‐Responsive and Metal‐Ion‐Free Self‐Assembly of DNA Nanostructures
Authors: Li Yongfei , Song Lei , Wang Bang , He Jianbo , Li Yulin , Deng Zhaoxiang , Mao Chengde
Published: April 2018

pH‐responsiveness has been widely pursued in dynamic DNA nanotechnology, owing to its potential in biosensing, controlled release, and nanomachinery. pH‐triggering systems mostly depend on specific designs of DNA sequences. However, sequence‐independent regulation could provide a more general tool to achieve pH‐responsive DNA assembly, which has yet to be developed. Herein, we propose a mechanism for dynamic DNA assembly by utilizing ethylenediamine (EN) as a reversibly chargeable (via protonation) molecule to overcome electrostatic repulsions. This strategy provides a universal pH‐responsivity for DNA assembly since the regulation originates from externally co‐existing EN rather than specific DNA sequences. Furthermore, it endows structural DNA nanotechnology with the benefits of a metal‐ion‐free environment including nuclease resistance. The concept could in principle be expanded to other organic molecules which may bring unique controls to dynamic DNA assembly.
Cu[B2(SO4)4] and Cu[B(SO4)2(HSO4)]—Two Silicate Analogue Borosulfates Differing in their Dimensionality: A Comparative Study of Stability and Acidity
Authors: Bruns Jörn , Podewitz Maren , Liedl Klaus R. , Janka Oliver , Pöttgen Rainer , Huppertz Hubert
Published: April 2018

Borosulfates are an ever‐expanding class of compounds and the extent of their properties is still elusive. Herein, the first two copper borosulfates Cu[B2(SO4)4] and Cu[B(SO4)2(HSO4)] are presented, which are structurally related but show different dimensionalities in their substructure: While Cu[B2(SO4)4] reveals an anionic chain,
[B(SO4)4/2]−, with both a twisted and a unique chair conformation of the B(SO4)2B subunits, Cu[B(SO4)2(HSO4)] reveals isolated [B2(SO4)4(HSO4)2]4− anions showing exclusively a twisted conformation. The complex anion can figuratively be obtained as a cut‐out from the anionic chain by protons. Comparative DFT calculations based on magnetochemical measurements complement the experimental studies. Calculation of the pKa values of the two conformers of the [B2(SO4)4(HSO4)2]4− anion revealed them to be more similar to silicic than to sulfuric acid, highlighting the close relationship to silicates.
Facile preparation of Cu(I) impregnated MIL‐101(Cr) and its use in a mixed matrix membrane for olefin/paraffin separation
Authors: Jung Jung Pyo , Kim Min June , Bae Youn‐Sang , Kim Jong Hak
Published: April 2018

Cu(I) impregnated MIL‐100(Cr) [denoted Cu@MIL‐101(Cr)] is fabricated by a facile method and utilized in mixed matrix membranes (MMMs) for propylene/propane separation. Cu(I) is prepared from a CuCl2 solution via mild reduction process using sodium sulfite as the reducing agent. The filler is incorporated into a polystyrene‐b‐polybutadiene‐b‐polystyrene (SBS) block copolymer matrix to form MMMs. As a result, both the permeability and selectivity of propylene/propane are improved after Cu(I) impregnation. The best performance is obtained for SBS/Cu@MIL‐101(Cr) MMM, and these values represent 17% and 54% improvements compared to those of SBS/MIL‐101(Cr) MMM, respectively. This result is attributed to the π‐complexation of the loaded Cu(I) by propylene gas, indicating that Cu@MIL‐101(Cr) with internal Cu(I) and a high pore volume acted as an effective filler to aid propylene/propane separation. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46545.
Pluronic‐based dual‐stimuli sensitive polymers capable of thermal gelation and pH‐dependent degradation for in situ biomedical application
Authors: Whang Chang‐Hee , Lee Hyung Kyung , Kundu Santanu , Murthy S. Narasimha , Jo Seongbong
Published: April 2018

Thermo‐sensitive hydrogels are considered ideal for applications in the biomedical fields for their biocompatibility, flexibility, tissue‐like water content, and reversible gelation property. By adjusting sufficient hydrophilic–hydrophobic balance in block copolymer structure, thermogel's critical gelation temperature (CGT) can be modified to be near the physiological temperature, which makes it an appealing candidate for in situ gel depot. In this study, we report successful syntheses of novel multiple block copolymer compounds, denoted as dual‐stimuli sensitive polymers (DSSPs), by copolymerizing Pluronic P104 (7100 Da) and 2,2‐bis(aminoethoxy)propane (BAP) using diisocyanate linkers, l‐lysine ethyl ester diisocyanate (DSSP‐1), and 1,6‐hexamethylene diisocyanate (DSSP‐2). Through effective elongation of polymer chain lengths (DSSP‐1: 41,760 Da, DSSP‐2: 41,230 Da), Pluronic P104's reversible thermal gelation properties were enhanced, as demonstrated by lowered CGTs (DSSP‐1: 36 °C, DSSP‐2: 38.7 °C; 15 wt %) that is near the physiological temperature. Furthermore, integration of acid‐labile BAP allowed rapid pH‐dependent degradation of the polymer, which was displayed by gel permeation chromatography and release profiles of nile red and irinotecan from polymeric micelles and gels, respectively. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46552.
Novel Imaging Modalities for Human Embryology and Applications in Education
Authors: Yamada Shigehito , Nakano Shiori , Makishima Haruyuki , Motoki Tamaki
Published: April 2018

Advances in imaging technology and development have recently enabled high‐resolution three‐dimensional (3D) imaging of embryos and fetuses. Embryos and fetuses stored at the Congenital Anomaly Research Center (Kyoto Collection of Human Embryos, Kyoto, Japan) were imaged using multiple modalities including magnetic resonance imaging, episcopic fluorescence image capture, and X‐ray computed tomography, both in absorption and phase‐contrasted configurations. Using the acquired images, 3D computer graphics were generated and a movie was created to gain further insight into understanding the developmental process. For educational purposes, self‐learning materials were also produced. The present review article briefly discusses each project and the results of imaging studies performed using specimens from the Kyoto Collection of Human Embryos. Anat Rec, 301:1004–1011, 2018. © 2018 Wiley Periodicals, Inc.
Maximum and minimum temperatures in the United States: Time trends and persistence
Authors: Gil‐Alana Luis A.
Published: April 2018

We investigate the time trends in the maximum and minimum temperatures in the United States from 1895 to 2017 using techniques that allow for fractional integration in the detrended series. In doing so we get more accurate estimates of the trends than those obtained using standard methods that impose either stationarity I(0) or nonstationarity I(1). Our results reveal evidence of significant positive trends in both maximum and minimum temperatures, while the difference between them show a significant negative trend as a consequence of the higher increase in the minimum temperatures. Evidence of stationary long memory behavior is also found in the three series examined.
Evaluation of a combined lignocellulosic / waste water bio‐refinery for the simultaneous production of valuable biochemical products and the remediation of acid mine drainage
Authors: Burman Nicholas W. , Harding Kevin G. , Sheridan Craig M. , Van Dyk Lizelle
Published: April 2018

The additional costs required for the pre‐treatment of lignocellulosic bio‐mass prior to enzymatic hydrolysis have limited the commercial implementation of lignocellulosic bio‐chemical production. The use of acidic mine drainage (AMD) water as an acid source for lignocellulosic pre‐treatment has recently been investigated. Large quantities of AMD in South Africa suggest that AMD can be obtained cheaply, thus reducing the cost and increasing the potential of lignocellulosic bio‐chemicals. Acidic mine drainage could undergo further remediation using sulfate‐reducing bacteria (SRB) so that the water is suitable for release. The feasibility of such a system could be greatly improved if this process were to be incorporated within a bio‐refinery, such that all fractions of the bio‐mass are used to produce multiple products. This paper investigates such a bio‐refinery system, and evaluates the different options based on the bio‐refinery complexity profile (BCP). Due to the abundance of grass in the regions where AMD is generated, this was found to be the most suitable feedstock. The most feasible bio‐refinery option was found to produce ethanol through fermentation of C6 sugars, although it is recommended that further investigation be conducted into additional high‐value bio‐chemicals from the C6 sugar platform. C5 sugars released in pre‐treatment could be used as a substrate by SRB for AMD remediation. Gasification and direct combustion of lignin had similar BCPs and thus further investigation is required to determine the preferred path. Similarly, further investigation is required for the best processing route for distillery silage. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd
Bayesian propensity scores for high‐dimensional causal inference: A comparison of drug‐eluting to bare‐metal coronary stents
Authors: Spertus Jacob V. , Normand Sharon‐Lise T.
Published: April 2018

High‐dimensional data provide many potential confounders that may bolster the plausibility of the ignorability assumption in causal inference problems. Propensity score methods are powerful causal inference tools, which are popular in health care research and are particularly useful for high‐dimensional data. Recent interest has surrounded a Bayesian treatment of propensity scores in order to flexibly model the treatment assignment mechanism and summarize posterior quantities while incorporating variance from the treatment model. We discuss methods for Bayesian propensity score analysis of binary treatments, focusing on modern methods for high‐dimensional Bayesian regression and the propagation of uncertainty. We introduce a novel and simple estimator for the average treatment effect that capitalizes on conjugacy of the beta and binomial distributions. Through simulations, we show the utility of horseshoe priors and Bayesian additive regression trees paired with our new estimator, while demonstrating the importance of including variance from the treatment regression model. An application to cardiac stent data with almost 500 confounders and 9000 patients illustrates approaches and facilitates comparison with existing alternatives. As measured by a falsifiability endpoint, we improved confounder adjustment compared with past observational research of the same problem.
Morbidity and mortality according to age following gastrectomy for gastric cancer
Authors:   the Dutch Upper Gastrointestinal Cancer Audit group, Nelen S D , Bosscha K , Lemmens V E P P , Hartgrink H H , Verhoeven R H A , de Wilt J H W
Published: April 2018

Background

This study investigated age-related differences in surgically treated patients with gastric cancer, and aimed to identify factors associated with outcome.

Methods

Data from the Dutch Upper Gastrointestinal Cancer Audit were used. All patients with non-cardia gastric cancer registered between 2011 and 2015 who underwent surgery were selected. Patients were analysed by age group (less than 70 years versus 70 years or more). Multivariable logistic regression was used to assess the influence of clinicopathological factors on morbidity and mortality.

Results

A total of 1109 patients younger than 70 years and 1206 aged 70 years or more were included. Patients aged at least 70 years had more perioperative or postoperative complications (41·2 versus 32·5 per cent; P < 0·001) and a higher 30-day mortality rate (7·9 versus 3·2 per cent; P < 0·001) than those younger than 70 years. In multivariable analysis, age 70 years or more was associated with a higher risk of complications (odds ratio 1·29, 95 per cent c.i. 1·05 to 1·59). Postoperative mortality was not significantly associated with age. In the entire cohort, morbidity and mortality were influenced most by ASA grade, neoadjuvant chemotherapy and type of resection.

Conclusion

ASA grade, neoadjuvant chemotherapy and type of resection are independent predictors of morbidity and death in patients with gastric cancer, irrespective of age.
Risk of recurrence and death in patients with breast cancer after delayed deep inferior epigastric perforator flap reconstruction
Authors: Adam H , Docherty Skogh A C , Edsander Nord Å , Schultz I , Gahm J , Hall P , Frisell J , Halle M , de Boniface J
Published: April 2018

Background

Postmastectomy reconstruction using a deep inferior epigastric perforator (DIEP) flap is increasingly being performed in patients with breast cancer. The procedure induces extensive tissue trauma, and it has been hypothesized that the release of growth factors, angiogenic agonists and immunomodulating factors may reactivate dormant micrometastasis. The aim of the present study was to estimate the risk of breast cancer recurrence in patients undergoing DIEP flap reconstruction compared with that in patients treated with mastectomy alone.

Methods

Each patient who underwent delayed DIEP flap reconstruction at Karolinska University Hospital, Sweden, between 1999 and 2013, was compared with up to four controls with breast cancer who did not receive a DIEP flap. The control patients were selected using incidence density matching with respect to age, tumour and nodal status, neoadjuvant therapy and year of mastectomy. The primary endpoint was breast cancer-specific survival. Survival analysis was carried out using Kaplan–Meier survival estimates and Cox proportional hazard regression analysis.

Results

The analysis included 250 patients who had 254 DIEP flap reconstructions and 729 control patients. Median follow-up was 89 and 75 months respectively (P = 0·053). Breast cancer recurrence developed in 50 patients (19·7 per cent) in the DIEP group and 174 (23·9 per cent) in the control group (P = 0·171). The 5-year breast cancer-specific survival rate was 92·0 per cent for patients with a DIEP flap and 87·9 per cent in controls (P = 0·032). Corresponding values for 5-year overall survival were 91·6 and 84·7 per cent (P < 0·001). After adjustment for tumour and patient characteristics and treatment, patients without DIEP flap reconstruction had significantly lower overall but not breast cancer-specific survival.

Conclusion

The present findings do not support the hypothesis that patients with breast cancer undergoing DIEP flap reconstruction have a higher rate of breast cancer recurrence than those who have mastectomy alone.
Integrated Cobalt Oxide Based Nanoarray Catalysts with Hierarchical Architectures: In Situ Raman Spectroscopy Investigation on the Carbon Monoxide Reaction Mechanism
Authors: Mo Shengpeng , Zhang Qi , Li Shuangde , Ren Quanming , Zhang Mingyuan , Xue Yudong , Peng Ruosi , Xiao Hailin , Chen Yunfa , Ye Daiqi
Published: April 2018

Herein, a facile strategy for the in situ growth of a Co3O4‐based precursor with unique hierarchical architectures oriented diagonal or perpendicular to Ni surfaces is reported. This strategy to prepare grafted ZIF‐67@Co3O4 and MOF‐199@Co3O4 precursor structures is based on a simple hydrothermal synthesis method to obtain the Co3O4 precursor and the subsequent in situ growth of ZIF‐67 and MOF‐199, respectively. The morphologies of the Co3O4 products can be tailored by controlling the solvent polarity and concentration of precipitants. CO is chosen as a probe molecule to evaluate the catalytic performance of the as‐synthesized Co3O4‐based oxide catalysts, and the structure–activity relationships are confirmed by using TEM, H2 temperature‐programmed reduction, X‐ray photoelectron spectroscopy, Raman spectroscopy and in situ Raman spectroscopy, and extended X‐ray absorption fine structure analysis. These analysis results demonstrate that irislike Co3O4 exhibits a high catalytic activity for CO oxidation and contains an abundance of surface defect sites (Co3+ species) to result in an excellent low‐temperature reducibility, oxygen vacancies and unsaturated chemical bonds on the surface. Moreover, we used in situ Raman spectroscopy to record the structural transformation of Co3O4 directly during the reaction, which confirmed that CO oxidation on the surface of Co3O4 can proceed through the Langmuir–Hinshelwood mechanism (<200 °C) and the Mars–van Krevelen mechanism (>200 °C).
A Technique for Obtaining Reference Measurements to Calibrate Deposition Models for Pipelines
Authors: Haugland Ingrid B. , Halstensen Maths
Published: April 2018

A laser method was extended and prepared for obtaining reference measurements to calibrate scale deposition thickness models for pipelines. The technique makes use of a laser device that is inserted into a pipe. Photographs of traces of laser light projected onto the internal wall of the pipe were obtained by slow‐shutter speed photography. Image processing was applied to find the shape and area of the traces. By comparison with images of a clean pipe, accurate estimations of the deposition thickness and shape can be made. The method succeeded in capturing various deposition shapes and quantifying the amount of scale present both in laboratory and field tests. The field tests were performed in a pneumatic conveying system afflicted with scaling, located in a metal production plant.
Highly Stabilized Zinc‐Air Batteries Based on Nanostructured Co3O4 Composites as Efficient Bifunctional Electrocatalyst
Authors: Nie Qi , Cai Yixiao , Xu Nengneng , Peng Luwei , Qiao Jinli
Published: April 2018

Zinc‐air batteries are expected to be ideal energy storage devices, showing features of high energy density, economic viability, and safety. To design such a system, it is necessary to develop active and durable electrocatalysts to catalyze the slow oxygen reduction reaction (ORR) during discharging and the oxygen evolution reaction (OER) during charging. In this study, a composite bifunctional catalyst (Co3O4@CNT@MC‐200) for use in zinc‐air batteries is prepared through a simple sol‐gel method, which combines Co3O4 with carbon nanotubes (CNTs) and mesoporous carbon (MC). Benefiting from its large specific surface area and, thus, a multitude of active sites, the Co3O4@CNT@MC‐200 composite bifunctional electrocatalyst shows excellent ORR performance in 0.1 M KOH, resulting in a half‐wave potential (E1/2) of 0.72 V and limiting diffusion current of 4.6 mA cm−2. In zinc‐air battery tests, a high discharge peak power density of 267 mW cm−2 and robust lifetime of 8700 min without attenuation is observed. Moreover, the physical properties of the reported catalyst were characterized. This study allows us to envisage the design of highly efficient composite electrocatalysts for zinc‐air batteries and a variety of other energy applications.
Nitrogen‐Doped Hierarchical Porous Carbon through One‐Step Activation of Bean Curd for High‐Performance Supercapacitor Electrode
Authors: Li Qiang , Wu Xiaozhong , Zhao Yi , Miao Zhichao , Xing Lingbao , Zhou Jin , Zhao Jinping , Zhuo Shuping
Published: April 2018

New nitrogen‐doped hierarchical porous carbons (HPCs) with large surface areas were prepared from bean curd through a one‐step impregnation activation method at 750 °C with CH3COOK as an activating agent. The porous carbons were characterized by a variety of techniques such as N2‐sorption analysis, scanning electron microscope (SEM), transmission electron microscope (TEM), and X‐ray photoelectron spectroscopy. The results show that there are numerous macropores with a pore size of ∼200 nm observed by SEM and TEM as well as micropores probed by N2‐sorption analysis, indicating a hierarchical porous structure for these carbon materials. The effect of activating agent dosage on the porous structure of carbon was carefully investigated. The Brunauer‐Emmett‐Teller specific surface area and nitrogen content for the optimized carbon are 2180 m2 g−1 and 2.62 at%, respectively. As evidenced by electrochemical measurements, the as‐prepared carbon has a good capacitive performance and the specific capacitance is calculated to be 284 F g−1 at a current density of 0.1 A g−1 in KOH electrolyte. More importantly, this carbon could deliver a high capacitance up to 118 F g−1 at a very high current density of 30 A g−1 due to its hierarchical porous structure, which will facilitate the ion transfer under high current density. Our research highlights the potential application of these HPCs as high‐performance electrode materials for electric double‐layer capacitors.
Fabricating Bis(phthalocyaninato) Terbium SIM into Tetrakis(phthalocyaninato) Terbium SMM with Enhanced Performance through Sodium Coordination
Authors: Chen Yuxiang , Liu Chao , Ma Fang , Qi Dongdong , Liu Qingyun , Sun Hao‐Ling , Jiang Jianzhuang
Published: April 2018

The non‐peripherally substituted 1,4,8,11,15,18,22,25‐octa(butoxy)‐phthalocyanine‐involved unsymmetrical heteroleptic bis(phthalocyaninato) terbium double‐decker, Tb(Pc){H[Pc(α‐OC4H9)8]} (Pc=unsubstituted phthalocyanine) (1), was revealed to exhibit typical single ion magnet (SIM) behavior with effective energy barrier, 180 K (125 cm−1), and blocking temperature, 2 K, due to the severe deviation of the terbium coordination polyhedron from square‐antiprismatic geometry. Fabrication of this double‐decker compound into the novel tetrakis(phthalocyaninato) terbium pseudo‐quadruple‐decker Na2{Tb(Pc)[Pc(α‐OC4H9)8]}2 (2) single molecule magnet (SMM) not only optimizes the coordination polyhedron of terbium ion towards the square‐antiprismatic geometry and intensifies the coordination field strength, but more importantly significantly enhances the molecular magnetic anisotropy in the unsymmetrical bis(phthalocyaninato) double‐decker unit, along with the change of the counter cation from H+ of 1 to Na+ of 2, leading to an significantly enhanced magnetic behavior with spin‐reversal energy barrier, 528 K (367 cm−1), and blocking temperature, 25 K. The present result is surely helpful towards developing novel tetrapyrrole lanthanide SMMs through rational design and self‐assembly from bis(tetrapyrrole) lanthanide single ion magnet (SIM) building block.
Energy‐Landscape‐Independent Kinetic Trap of an Incomplete Cage in the Self‐Assembly of a Pd2L4 Cage
Authors: Nakagawa Masanori , Kai Shumpei , Kojima Tatsuo , Hiraoka Shuichi
Published: April 2018

A kinetic trap is the metastable species that is transiently or constantly produced during the reaction by trapping in a deep energy well. In most cases, the reactivity of kinetically trapped species is relatively low under the reaction conditions. Herein, we report another type of kinetically trapped species that is an incomplete cage (IC) intermediate produced during the self‐assembly of a Pd2L4 cage from ditopic ligand (L) and PdII ions with a certain lifetime, although IC has a high enough reactivity to be converted into the cage with the reaction of free L, which was confirmed by the reaction of the isolated IC and L under the self‐assembly conditions. IC was kinetically trapped not because IC lies on the bottom of a deep energy well but because the conversion of the intermediates essential for the conversion of IC to the cage preferentially takes place; IC was kinetically trapped independently of the shape of the energy landscape of the self‐assembly.
Efficient Synthesis of a Wide‐Range Absorbing Azaphthalocyanine Dark Quencher and Its Application to Dual‐Labeled Oligonucleotide Probes for Quantitative Real‐Time Polymerase Chain Reactions
Authors: Demuth Jiri , Kucera Radim , Kopecky Kamil , Havlínová Zuzana , Libra Antonín , Novakova Veronika , Miletin Miroslav , Zimcik Petr
Published: April 2018

Unsymmetrical dialkylamino‐substituted zinc azaphthalocyanine (AzaPc) exhibits unique spectral and photophysical properties for dark quenchers of fluorescence in DNA hybridization probes. The panchromatic light absorption of AzaPc from 300 nm up to at least 700 nm and its lack of fluorescence make it an ideal candidate for a universal dark quencher. To prove this experimentally, oligodeoxyribonucleotide probes were labeled at the 3′‐end by this AzaPc and at the 5′‐end by a fluorophore used in the polymerase chain reaction (PCR)—that is, fluorescein, CAL Fluor Red 610, and Cy5. AzaPc showed a significantly higher quenching efficiency compared to the commercially available dark quenchers (BHQ‐1, BHQ‐2, BBQ‐650) in a developed model of TaqMan PCR assay. The AzaPc‐labeled probe proved to also be useful in a practical PCR assay for the quantification of the SLCO2B1 transporter gene expression. The constructed calibration curves indicated linearity in the range from 102 to 107 of target copies.
Bromo‐ and Polybromoantimonates(V): Structural and Theoretical Studies of Hybrid Halogen‐Rich Halometalate Frameworks
Authors: Adonin Sergey A. , Bondarenko Mikhail A. , Abramov Pavel A. , Novikov Alexander S. , Plyusnin Pavel E. , Sokolov Maxim N. , Fedin Vladimir P.
Published: April 2018

Cation‐dependent reactions “[SbBr6]3−+Br2+HBr+CationBrx” result in the formation of bromide/polybromide complexes with zero‐, one‐, two‐, or three‐dimensional supramolecular frameworks and different Br/Sb ratios (up to 11). Seven new compounds representing six structural types were characterized by XRD and thermogravimetric analysis and DFT calculations enabled estimation of the energies of the Br⋅⋅⋅Br contacts (1.1–4.6 kcal mol−1).
Kunststoffe
Authors: Wöhrle Dieter
Published: April 2018

Kunststoffe basierend auf fossilen Ressourcen wie Erdöl sind Werkstoffe unserer Zeit und werden auch in Zukunft große Bedeutung haben. Heute liegt weltweit die Produktion von Kunststoffen bei über 300 Mio. t pro Jahr. Der Artikel behandelt den Verbrauch fossiler Rohstoffe und den energetischen Bedarf zur Herstellung der Kunststoffe. Aus den Bereichen Standard‐, Techno‐ und Hochleistungskunststoffe werden Beispiele behandelt und der Bedarf von Kunststoffen in der Zukunft vorgestellt. Die Verwendung abbaubarer biobasierter Kunststoffe wird in Zukunft zunehmen. Beispiele über toxikologische Probleme im Zusammenhang mit Kunststoffen werden genannt. Für das Recycling von Kunststoffabfällen als Wertstoffe wurden inzwischen geeignete Verfahren entwickelt, die aber noch weltweit umgesetzt werden müssen. Probleme existieren zu Zeit mit Kunststoffen in der Umwelt insbesondere in den Meeren.
Where there is smoke, there is not always fire
Authors: Johnson David C. , Elmore Joann G.
Published: April 2018

False‐positive cancer screening tests are a troubling yet inevitable facet of cancer screening. Although false‐positive examinations are known to lead to short‐term anxiety and additional testing, to the authors' knowledge little data have existed regarding the long‐term impact of these false‐positive experiences on future cancer screening behavior until the work by Taksler et al.

See also pages 2390‐8, this issue.
Implications of false‐positive results for future cancer screenings
Authors: Taksler Glen B. , Keating Nancy L. , Rothberg Michael B.
Published: April 2018

BACKGROUND

False‐positive cancer screening results may affect a patient's willingness to obtain future screening.

METHODS

The authors conducted logistic regression analysis of 450,484 person‐years of electronic medical records (2006‐2015) in 92,405 individuals aged 50 to 75 years. Exposures were false‐positive breast, prostate, or colorectal cancer screening test results (repeat breast imaging or negative breast biopsy ≤3 months after screening mammography, repeat prostate‐specific antigen [PSA] test ≤3 months after PSA test result ≥4.0 ng/mL or negative prostate biopsy ≤3 months after any PSA result, or negative colonoscopy [without biopsy/polypectomy] ≤6 months after a positive fecal occult blood test). Outcomes were up‐to‐date status with breast or colorectal cancer screening. Covariates included prior screening history, clinical information (eg, family history, obesity, and smoking status), comorbidity, and demographics.

RESULTS

Women were more likely to be up to date with breast cancer screening if they previously had false‐positive mammography findings (adjusted odds ratio [AOR], 1.43 [95% confidence interval, 1.34‐1.51] without breast biopsy and AOR, 2.02 [95% confidence interval, 1.56‐2.62] with breast biopsy; both P<.001). The same women were more likely to be up to date with colorectal cancer screening (AOR range, 1.25‐1.47 depending on breast biopsy; both P<.001). Men who previously had false‐positive PSA testing were more likely to be up to date with colorectal cancer screening (AOR, 1.22 [P = .039] without prostate imaging/biopsy and AOR, 1.60 [P = .028] with imaging/biopsy). Results were stronger for individuals with more false‐positive results (all P≤.005). However, women with previous false‐positive colorectal cancer fecal occult blood test screening results were found to be less likely to be up to date with breast cancer screening (AOR, 0.73; P<.001).

CONCLUSIONS

Patients who previously had a false‐positive breast or prostate cancer screening test were more likely to engage in future screening. Cancer 2018;124:2390‐8. © 2018 American Cancer Society.
A New Phase Transfer Strategy to Convert Protein‐Capped Nanomaterials into Uniform Fluorescent Nanoclusters in Reverse Micellar Phase
Authors: Sahu Dillip Kumar , Pal Tapas , Sahu Kalyanasis
Published: April 2018

A new phase transfer strategy to convert aqueous phase protein‐protected nanomaterials into fluorescent nanoclusters in the reverse micellar environment is introduced using bovine serum albumin (BSA)‐protected silver nanoclusters (AgNCs) and nanoparticles (AgNPs) as an example. The basic pH employed in the fabrication of protein‐protected nanoclusters induces the the protein capping to be negatively charged and facilitates the transfer process of the nanomaterials from aqueous phase to a cationic gemini surfactant (16‐2‐16)/hexane/hexanol/water reverse micelle (RM) phase. The original fluorescence characteristics of the seed nanocluster is retained after the transfer process. Strikingly, when both the nanomaterials (AgNCs and AgNPs) coexist in the aqueous feed solution, they are exclusively converted into uniform nanoclusters in the RM extract with enhanced fluorescence intensity.
Be‐ and Mg‐Based Electron and Anion Sponges
Authors: Montero‐Campillo M. Merced , Mó Otilia , Yáñez Manuel , Alkorta Ibon , Elguero José
Published: April 2018

By using G4(MP2) high‐level ab initio methods, we show that Be and Mg derivatives of cyclopropane exhibit very large electron and anion affinities, reflecting the electron‐deficient nature of the −BeX and −MgX (X=CH3, F, Cl, CN) substituents. In particular, these compounds present electron affinities among the largest reported for neutral closed‐shell systems. Their anion affinities are also among the largest reported for single neutral molecules, indeed higher than the 1,8‐diBeX‐naphthalene (X=F, Cl, CN) derivatives, recently shown to behave as anion sponges. Quite unexpectedly, our results indicate that the intrinsic anion affinity of the Mg‐containing compounds is higher than that of the Be‐containing analogs.
Advanced filter design technique based on equivalent circuits and coupling matrix segmentation
Authors: Martinez Martinez David , Pons Abenza Alejandro , Romera Perez Antonio , Hinojosa Juan , Quesada‐Pereira Fernando , Alvarez‐Melcon Alejandro , Guglielmi Marco
Published: April 2018

This paper presents a technique for the efficient design of bandpass waveguide microwave filters using a segmentation technique applied to an equivalent circuit. The technique is based on first developing an equivalent circuit that synthesizes the desired transfer function. Then, the different parts of the real physical structure are optimized by segmenting this equivalent circuit. The technique was originally developed for in‐line filters, and the main contribution of this paper is in the combination of this technique with the coupling matrix formalism. In this way, we adapt for the first time this design strategy to the design of complex coupling topologies, beyond the in‐line configuration. As an example, a complex sixth‐order dual‐mode filter, implemented in all‐inductive waveguide technology, is designed using the new coupling matrix segmentation technique, showing the effectiveness of the presented theory. A prototype of the filter has been manufactured, and the accuracy of the design technique is verified by measurements on the real prototype.
Tr1 cell immunotherapy promotes transplant tolerance via de novo Tr1 cell induction in mice and is safe and effective during acute viral infection
Authors: Jofra Tatiana , Di Fonte Roberta , Galvani Giuseppe , Kuka Mirela , Iannacone Matteo , Battaglia Manuela , Fousteri Georgia
Published: April 2018

Tr1 cell therapy is considered an emerging approach to improve transplant tolerance and enhance allogeneic graft survival. However, it remains unclear how Tr1 cells promote transplant tolerance and whether they will be safe and stable in the face of an acute viral infection. By employing a mouse model of pancreatic islet transplantation, we report that Tr1 cell therapy promoted transplant tolerance via de novo induction of Tr1 cells in the recipients. Acute viral infection with lymphocytic choriomeningitis virus (LCMV) had no impact on Tr1 cell number and function, neither on the Tr1 cells infused nor on the ones induced, and that was reflected in the robust maintenance of the graft. Moreover, Tr1 cell immunotherapy had no detrimental effect on CD8 and CD4 anti‐LCMV effector T‐cell responses and viral control. Together, these data suggest that Tr1 cells did not convert to effector cells during acute infection with LCMV, maintained transplant tolerance and did not inhibit antiviral immunity.