bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrathin Yttria‐Stabilized Zirconia as a Flexible and Stable Substrate for Infrared Nano‐Optics
Authors: Gopalan Kavitha K. , Rodrigo Daniel , Paulillo Bruno , Soni Kamal K. , Pruneri Valerio
Published: December 2018

Infrared (IR) technologies have become increasingly relevant as they offer a wide range of applications, from thermal imaging to chemical and biological vibrational spectroscopy. Substrate materials, such as calcium fluoride and zinc selenide, are commonly used for IR optics. Unfortunately, they are typically fragile or hygroscopic, thus potentially producing problems during device fabrication and in the long‐term functional operation. Here, yttria‐stabilized zirconia (YSZ) ceramic is introduced as a flexible and stable platform for IR nano‐optics. In particular, the YSZ substrate is combined with metallic nanostructures and graphene to demonstrate new plasmonic, polarizing, and transparent heating devices, which, at the same time, enable high‐temperature processing and withstand harsh environments thanks to the high YSZ thermal and chemical stability. In addition, it is shown that the YSZ substrate is mechanically flexible, ideally suited for making foldable or bendable devices, and for low‐cost large‐scale roll‐to‐roll fabrication processes. The combination of all the aforesaid features, which are not available from other alternative materials, and this work offers compelling evidence that ultrathin YSZ is a unique substrate for IR applications.
Electrical Control of Electromagnetically Induced Transparency by Terahertz Metamaterial Funneling
Authors: Jung Hyunseung , Jo Hyunwoo , Lee Wonwoo , Kim Beom , Choi Hyunyong , Kang Moon Sung , Lee Hojin
Published: December 2018

Electromagnetically induced transparency (EIT) analogs using metamaterials have diverse applications, including nonlinear optics, telecommunications, and biochemical sensors. These EIT analogs can be actively controlled by embedding semiconducting materials into metamaterial structures, but most active EIT metamaterials require complex optical setups and complicated fabrication processes. Graphene‐based EIT metamaterials are some of the most promising active EIT systems because of their simple controllability by electrical bias, but related researches have so far been limited to theoretical or numerical studies. Here, experimentally verified graphene EIT metamaterials are provided by controlling the terahertz funneling of the unique metaatom structures. The proposed active EIT metamaterials are fabricated on flexible and ultrathin polyimide films to acquire the lowest substrate insertion losses and achieve a 1 ps group delay change at the transmission peak of the EIT analog. Moreover, because the proposed metamaterials exhibit resonance properties that vary depending on the polarization direction, the phase delay can be controlled up to 80° from the proposed metamaterials by rotating the incident polarization to the orthogonal direction. Overall, by controlling the group and phase delay of incident waves in a single metamaterial device simultaneously, a multifunctional active tuning system can be realized in the terahertz range.
A Narrowband Photo‐Thermoelectric Detector Using Photonic Crystal
Authors: Monshat Hosein , Liu Longju , Lu Meng
Published: December 2018

Here, a wavelength‐specific photo‐thermoelectric (PTE) device is reported that achieves narrowband optical absorption and thermoelectric conversion functions using a stack of thin films on a grating‐patterned substrate. Conventional PTE devices are broadband with the absorption of electromagnetic radiation from ultraviolet to terahertz. There are demands for PTE devices that can exhibit narrowband response at a desired wavelength. Here, the narrowband PTE device consists of a photonic crystal (PC) filter with metal cladding and a thin‐film thermocouple. The PC‐PTE design is investigated numerically to illustrate the underlying energy conversion mechanism. The device is fabricated using nanoreplica molding followed by coating of thin films. The fabricated metal‐cladding PC resonator exhibits a narrowband optical absorption with a resonant absorption coefficient of 85.4% and full‐width‐half‐maximum of 14.8 nm in the visible wavelength range. The PTE measurements show that the thermoelectric output is sensitive to the coupling of incident light and guided‐mode resonance modes. Illuminated under the resonant condition, the PTE device exhibits a responsivity and noise equivalent power of 0.26 V W−1 and 7.5 nW Hz−1/2, respectively. This PC‐PTE technology has the unique attributes of narrowband detection, large surface area, and low cost for the potential application in sensors, optical spectroscopy, and imaging.
Layer‐Dependent Dielectric Function of Wafer‐Scale 2D MoS2
Authors: Song Baokun , Gu Honggang , Fang Mingsheng , Chen Xiuguo , Jiang Hao , Wang Renyan , Zhai Tianyou , Ho Yen‐Teng , Liu Shiyuan
Published: December 2018

Wafer‐scale, high‐quality, and layer‐controlled 2D MoS2 films on c‐sapphire are synthesized by an innovative two‐step method. The dielectric functions of MoS2 ranging from the monolayer to the bulk are investigated by spectroscopic ellipsometry over an ultra‐broadband (0.73–6.42 eV). Up to five critical points (CPs) in the dielectric function spectra are precisely distinguished by CP analysis, and their physical origins are identified in the band structures with the help of first‐principles calculations. Results demonstrate that the center energies of these CPs exhibit intriguing layer dependency, which are interpreted by the intrinsic layer‐dependent transitions in MoS2. Specially, the change in the imaginary part of the dielectric functions versus the thickness exhibits a “W” like curve, and the two valley bottoms appear at about four‐layer and 10‐layer respectively. These complex fluctuations are attributed to the alternating domination of the decreasing excitonic effect, the increasing joint density of states, and the mass density increase in relative thick MoS2 samples.
A Facile Solution‐Processed Light Manipulation Structure for Organic Solar Cells
Authors: Chen Jing‐De , Wang Shu , Sun Qi , Li Yan‐Qing , Tang Jian‐Xin
Published: December 2018

Light manipulation strategy plays a critical role in increasing the light harvesting of organic solar cells (OSCs). However, the incorporation of light manipulation structures in OSCs is usually hindered by complex lithography‐based techniques. Herein, a facile and solution‐processed structured ZnO film is proposed, consisting of ZnO colloidal spheres (CS) embedded in ZnO nanoparticles for broadband light scattering and antireflection in OSCs. By combining monodisperse ZnO CS (m‐ZnO) as an electron collection layer and polydisperse ZnO CS (p‐ZnO) as an antireflection layer, single‐junction OSCs yield a substantial increase in photocurrent and power conversion efficiency by 14.63% compared to the reference cell with a flat structure. The experimental and theoretical characterizations ascribe the performance enhancement to the enhanced absorption due to a synergetic interplay of p‐ZnO‐induced antireflection and surface plasmonic scattering excited by corrugated metal electrode. It is anticipated that this light manipulation method represents a facile yet cost‐effective route to achieving high‐efficiency OSCs for commercially viable photovoltaic applications.
Vapor‐Phase Growth of CsPbBr3 Microstructures for Highly Efficient Pure Green Light Emission
Authors: Lan Shangui , Li Wancai , Wang Shuai , Li Junze , Wang Jun , Wang Haizhen , Luo Hongmei , Li Dehui
Published: December 2018

All‐inorganic lead halide perovskites have been extensively studied in the past several years due to their superior stability against moisture, oxygen, light, and heat compared with their organic–inorganic counterparts. CsPbBr3 with suitable band gap and ultrahigh photoluminescence quantum yield is a promising candidate for pure green emitter in the backlighting display to fill the so‐called “green gap.” Here, vapor‐phase growth of CsPbBr3 microspheres is reported for highly efficient pure green light emission. The as‐synthesized microspheres exhibit a stronger photoluminescence (PL) intensity with a photoluminescence quantum yield of 75% resulting from the lower energy of longitudinal optical phonons revealed by temperature dependent PL studies. Importantly, with the diameter increasing from 2 to 50 µm the PL peak positions of the microspheres can be readily tuned from 527 to 539 nm, well filling the so‐called “green gap.” The red‐shift with increasing diameter can be ascribed to the reabsorption process during the photon propagation inside the microspheres. The studies provide a route to improve the photoluminescence quantum yield in all‐inorganic lead halide perovskites, but also suggest an alternative approach to achieve the pure green emission for the backlighting display.
Rational Molecular Engineering of Glutamate Dehydrogenases for Enhancing Asymmetric Reductive Amination of Bulky α‐Keto Acids
Authors: Yin Xinjian , Liu Yayun , Meng Lijun , Zhou Haisheng , Wu Jianping , Yang Lirong
Published: December 2018

Glutamate dehydrogenases (GluDHs) are promising biocatalysts for the synthesis of chiral α‐amino acids by asymmetric reductive amination of α‐keto acids. However, their strict substrate specificity limits their applications. To address this problem, we developed a molecular engineering method for GluDHs that enhances the asymmetric reductive amination of bulky α‐keto acids. Based on rational design, a “cave” located in the active site pocket of PpGluDH (GluDH from Pseudomonas putida), which plays an essential role in substrate recognition, was tailored to facilitate the accepting of bulky substrates. Two mutants (A167G and V378A) were discovered to have significantly enhanced catalytic activity toward 2‐oxo‐4‐[(hydroxy)(methyl)phosphinyl]butyric acid (PPO) and several other bulky substrates. This molecular engineering method was then applied to ten other GluDHs from different sources and with different properties. All engineered GluDHs acquired substantial improvements in PPO‐oriented catalytic activity. The most efficient mutant of NADP+ (nicotinamide adenine dinucleotide phosphate)‐specific GluDHs showed up to 1820‐fold increased activity and the specific activity reached 111.02 U/mg‐protein. The NAD+ (nicotinamide adenine dinucleotide)‐specific GluDHs, which have no detectable wild type activity toward PPO, acquired a considerable level of activity (1.90–29.48 U/mg‐protein). In batch production of L‐phosphinothricin, these “cave‐tailored” GluDHs exhibited markedly improved catalytic efficiencies compared with their wild types and ee values of >99%. The space‐time yields (STY) varied from 818.16 to 1482.96 g ⋅ L−1 ⋅ d−1, suggesting potential practical applications of these mutants.

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Simulating Transport of Soft Matter in Micro/Nano Channel Flows with Dissipative Particle Dynamics
Authors: Xu Ziyang , Yang Ye , Zhu Guolong , Chen Pengyu , Huang Zihan , Dai Xiaobin , Hou Cuiling , Yan Li‐Tang
Published: December 2018

The flow‐induced transport of various soft matter systems through a fluidic channel has recently attracted great interest due to its significance ranging from the understanding of several chemical and biological processes to potential industrial and technical applications. Dynamic simulation and modeling can yield an insight into the detailed conformational, dynamical, and transport properties of soft matter systems, which is necessary to understand the transport properties of biological macromolecules in living organisms. As a mesoscopic particles‐based simulation technique, dissipative particle dynamics (DPD) has quickly been adopted as a promising approach for simulating dynamic and rheological properties of simple and complex fluids as well as the events taking place inside the fluidic channels. Here, the DPD method widely used in predicting the channel flow containing various soft matter systems is reviewed. The general aspect and basic formulations of DPD are introduced, and different boundary conditions are presented for wall‐bounded flows. In addition, the models based on DPD developed to simulate flow‐induced transport through fluidic channels for some typical soft matter systems are discussed, including red blood cells, vesicles, polymers, and biomacromolecules. Finally, the future directions to signify the framework in enhancing the design of novel functional systems and beyond are discussed.
Large‐Area All‐Printed Temperature Sensing Surfaces Using Novel Composite Thermistor Materials
Authors: Katerinopoulou Dimitra , Zalar Peter , Sweelssen Jorgen , Kiriakidis George , Rentrop Corné , Groen Pim , Gelinck Gerwin H. , van den Brand Jeroen , Smits Edsger C. P.
Published: December 2018

Surfaces which can accurately distinguish spatial and temporal changes in temperature are critical for not only flow sensors, microbolometers, process control, but also future applications like electronic skins and soft robotics. Realizing such surfaces requires the deposition of thousands of thermal sensors over large areas, a task ideally suited for printing technologies. Negative temperature coefficient (NTC) ceramics represent the industry standard in temperature sensing due to their high thermal coefficient and excellent stability. A drawback is their complex and high temperature fabrication process and high stiffness, prohibiting their monolithic integration in large area or flexible applications. As a remedy, a printable NTC composite that combines a rapid and scalable all‐printed fabrication process with performances that are on par with conventional NTC ceramics is demonstrated. The composite consists of micrometer‐sized manganese spinel oxide particles dispersed in a benzocyclobutene matrix. The sensor has a B coefficient of 3500 K, with a 4.0% change in resistance at 25 °C, comparable to bulk ceramics. The selected polymer binder yields a composite exhibiting less than a 1 °C change in resistance to changes in humidity. The sensor's scalability is validated by demonstration of a A4‐sized temperature sensing sheet consisting of over 400 sensors.
Hierarchically Structured Ultraporous Iridium‐Based Materials: A Novel Catalyst Architecture for Proton Exchange Membrane Water Electrolyzers
Authors: Faustini Marco , Giraud Marion , Jones Deborah , Rozière Jacques , Dupont Marc , Porter Thomas R. , Nowak Sophie , Bahri Mounib , Ersen Ovidiu , Sanchez Clément , Boissière Cédric , Tard Cédric , Peron Jennifer
Published: December 2018

Iridium oxide is the gold‐standard catalyst for the oxygen evolution reaction (OER) in acidic media due to its unmatched activity and stability. Here, a new catalyst architecture comprising a nanoneedle network of iridium‐containing oxides assembled into macroporous micrometric particles with ≈75% of porosity is reported. The rationally designed porous hierarchical structure optimizes the accessibility of reactants and products to the surface of the nanoparticles and maximizes catalyst activity. The materials are easily prepared from aqueous solutions by an industrially viable spray‐drying route through an evaporation self‐assembly mechanism. The versatility of the process enables the preparation of mixed oxides with low iridium content, particles with tunable crystallinity, and various iridium surface species with high electrochemical activity. Highly porous Ir0.7Ru0.3O2 outperforms commercial iridium oxide. These materials also represent an ideal platform to assess the reactivity of the iridium and oxygen species involved in the oxygen evolution reaction. Furthermore, it is demonstrated that these highly porous particles are optimal building blocks to be integrated into catalyst layers, without the drawbacks associated with the use of discrete nanoparticles. Fresh‐ and end‐of‐test membrane–electrode assemblies' characterization shows that their particular architecture is preserved upon catalyst layer preparation and after operation in a proton‐exchange membrane electrolysis cell.
Two‐Step Activated Carbon Cloth with Oxygen‐Rich Functional Groups as a High‐Performance Additive‐Free Air Electrode for Flexible Zinc–Air Batteries
Authors: Kordek Karolina , Jiang Lixue , Fan Kaicai , Zhu Zhengju , Xu Li , Al‐Mamun Mohammad , Dou Yuhai , Chen Shan , Liu Porun , Yin Huajie , Rutkowski Piotr , Zhao Huijun
Published: December 2018

A flexible air electrode (FAE) with both high oxygen electrocatalytic activity and excellent flexibility is the key to the performance of various flexible devices, such as Zn–air batteries. A facile two‐step method, mild acid oxidation followed by air calcination that directly activates commercial carbon cloth (CC) to generate uniform nanoporous and super hydrophilic surface structures with optimized oxygen‐rich functional groups and an enhanced surface area, is presented here. Impressively, this two‐step activated CC (CC‐AC) exhibits superior oxygen electrocatalytic activity and durability, outperforming the oxygen‐doped carbon materials reported to date. Especially, CC‐AC delivers an oxygen evolution reaction (OER) overpotential of 360 mV at 10 mA cm−2 in 1 m KOH, which is among the best performances of metal‐free OER electrocatalysts. The practical application of CC‐AC is presented via its use as an FAE in a flexible rechargeable Zn–air battery. The bendable battery achieves a high open circuit voltage of 1.37 V, a remarkable peak power density of 52.3 mW cm−3 at 77.5 mA cm−3, good cycling performance with a small charge–discharge voltage gap of 0.98 V and high flexibility. This study provides a new approach to the design and construction of high‐performance self‐supported metal‐free electrodes.
Spectral Engineering of Semitransparent Polymer Solar Cells for Greenhouse Applications
Authors: Shi Hui , Xia Ruoxi , Zhang Guichuan , Yip Hin‐Lap , Cao Yong
Published: December 2018

In this study, a wavelength selective semitransparent polymer solar cell (ST‐PSC) with a proper transmission spectrum for plant growth is proposed for greenhouse applications. A ternary strategy combining a wide bandgap polymer donor with a near‐infrared absorbing nonfullerene acceptor and a high electron mobility fullerene acceptor is introduced to achieve PSCs with power conversion efficiency (PCE) over 10%. The addition of PC71BM into J52:IEICO‐4F binary blend contributes to the suppressed trap‐assisted recombination, enhanced charge extraction, and improved open‐circuit voltage simultaneously. ST‐PSC based on the J52:IEICO‐4F:PC71BM ternary blend shows an optimized performance with PCE of 7.75% and a defined crop growth factor of 24.8%. Such high‐performance ST‐PSC is achieved by carefully engineering the absorption spectrum of the light harvesting materials. As a result, the transmission spectra of the semitransparent devices are well‐matched with the absorption spectra of the photoreceptors, such as chlorophylls, in green plants, which provides adequate lighting conditions for photosynthesis and plant growth, and therefore making it a competitive candidate for photovoltaic greenhouse applications.
Coaching for Chaos: A Qualitative Study of Instructional Methods for Multipatient Management in the Emergency Department
Authors: Chan Teresa M. , Van Dewark Kenneth , Sherbino Jonathan , Lineberry Matthew
Published: December 2018

Background

Busy environments, like the emergency department (ED), require teachers to develop instructional strategies for coaching trainees to function within these same environments. Few studies have documented the strategies used by emergency physician (EP)‐teachers within these busy, chaotic environments, instead emphasizing teaching in more predictable environments such as the outpatient clinic, hospital wards, or operating room. The authors sought to discover what strategies EP‐teachers were using and what trainees recalled experiencing when learning to handle these unpredictable, overcrowded, complex, multipatient environments.

Method

An interpretive description study was conducted at multiple teaching hospitals affiliated with McMaster University from July 2014 to May 2015. Participants (10 EP‐teachers and 10 junior residents) were asked to recall teaching strategies related to handling ED patient flow. Participants were asked to describe techniques that they used, observed, or experienced as trainees. Two independent coders read through interview transcripts, analyzing these documents inductively and iteratively.

Results

Two main types of strategies to teach ED management were discovered: 1) workplace‐based methods, including both observation and in situ instruction; and 2) principle‐based advice. The most often described techniques were workplace‐based methods, which included a variety of in situ techniques ranging from conversations to managerial coaching (e.g., collaborative problem‐solving of real‐life administrative dilemmas).

Conclusions

A mix of strategies are used to teach and coach trainees to handle multipatient environments. Further research is required to determine how to optimize the use of these techniques and innovate new strategies to support the learning of these crucial skills.
Geophagy among nonhuman primates: A systematic review of current knowledge and suggestions for future directions
Authors: Pebsworth Paula A. , Huffman Michael A. , Lambert Joanna E. , Young Sera L.
Published: December 2018

Objectives

Geophagy, the intentional consumption of earth, is widely practiced among humans and other mammals, but its causes are not well understood. Given the growing number of reports of geophagy among nonhuman primates (NHP), we sought to (1) advance and codify our understanding of the patterns and functional and evolutionary significance of geophagy among NHP and (2) provide a research agenda for a more unified approach to its study.

Methods

We systematically reviewed all available literature on NHP geophagy, extracted available data on taxa, geography, climate, diet, sex, age‐class, reproductive status, and the characteristics of the earth. We used these data to evaluate three major hypotheses about geophagy, that it is protective, provides mineral supplementation, and is nonadaptive.

Results

We identified 287 accounts of geophagy among 136 species, adding 79 new primate species to the list of those considered in prior reviews. Nineteen percent of species were in the suborder Strepsirrhini, while 81% were in the suborder Haplorrhini. There were reports of geophagy from 9 of the 17 families and 39 of the 76 genera currently recognized by the International Union for Conservation of Nature.

Discussion

The limited evidence suggests that geophagy is adaptive, and provides protection and mineral supplementation. We specify the behavioral, dietary, and soil data required to more rigorously investigate these hypotheses across representative species of all taxonomic groups, geographical regions, and dietary classification. Given the plausibility of geophagy for maintaining the health of both wild and captive populations, we urge further study and conservation of geophagy sites.
Genetic contributions to dental dimensions in brown‐mantled tamarins (Saguinus fuscicollis) and rhesus macaques (Macaca mulatta)
Authors: Hardin Anna M.
Published: December 2018

Objectives

The use of dental metrics in phylogenetic reconstructions of fossil primates assumes variation in tooth size is highly heritable. Quantitative genetic studies in humans and baboons have estimated high heritabilities for dental traits, providing a preliminary view of the variability of dental trait heritability in nonhuman primate species. To expand upon this view, the heritabilities and evolvabilities of linear dental dimensions are estimated in brown‐mantled tamarins (Saguinus fuscicollis) and rhesus macaques (Macaca mulatta).

Materials and methods

Quantitative genetic analyses were performed on linear dental dimensions collected from 302 brown‐mantled tamarins and 364 rhesus macaques. Heritabilities were estimated in SOLAR using pedigrees from each population, and evolvabilities were calculated manually.

Results

Tamarin heritability estimates range from 0.19 to 0.99, and 25 of 26 tamarin estimates are significantly different from zero. Macaque heritability estimates range from 0.08 to 1.00, and 25 out of 28 estimates are significantly different from zero.

Discussion

Dental dimensions are highly heritable in captive brown‐mantled tamarins and free‐ranging rhesus macaques. The range of heritability estimates in these populations is broadly similar to those of baboons and humans. Evolvability tends to increase with heritability, although evolvability is high relative to heritability in some dimensions. Estimating evolvability helps to contextualize differences in heritability, and the observed relationship between evolvability and heritability in dental dimensions requires further investigation.
Opioid analgesic use and patient‐reported pain outcomes after rhinologic surgery
Authors: Riley Charles A. , Kim Matthew , Sclafani Anthony P. , Kallush Aron , Kjaer Klaus , Kacker Ashutosh S. , Tabaee Abtin
Published: December 2018

Background

Opioid‐based analgesics are routinely prescribed after elective rhinologic surgery. Balancing appropriate pain management while avoiding overprescription necessitates an evidence‐based approach.

Methods

Patients undergoing elective rhinologic surgery, including endoscopic sinus surgery (ESS), septoplasty, or ESS with septoplasty, were prospectively enrolled. Patients completed demographic and psychometric questionnaires assessing attitudes toward pain, baseline anxiety, and depression before surgery. Postoperatively, patients documented peak pain levels (0‐100 visual analog scale) and daily prescription and nonprescription medication requirements over a 2‐week period.

Results

Of the 42 patients enrolled, 15 underwent ESS, 14 septoplasty, and 13 ESS with septoplasty. Five patients (11.9%) reported a history of chronic pain before surgery. Patients were given a median of 30 opioid pain pills after surgery: acetaminophen with codeine 325/30 mg (10 patients) or oxycodone with acetaminophen 5/325 mg (32 patients). Patients had a median of 27 pills left over at the end of the study period. Median peak pain levels for all procedures were 22 (range, 0‐94) on day 0, 26.5 (range, 0‐86) on day 1, 8.5 (range, 0‐85) on day 3, and 3 (range, 0‐52) on day 7. Median opioid requirements measured in morphine milligram equivalents (MME) over those same days were 6.0, 4.1, 0, and 0, respectively.

Conclusion

Postoperative pain after elective rhinologic surgery appears to peak over the first 3 days and decreases rapidly afterward. Most patients require a few doses of opioid analgesics. Opioid requirements and pain levels did not vary based on surgeon, type and extent of surgery, and demographic factors. Judicious prescribing of opioid medication after rhinologic surgery represents a practical opportunity for rhinologists and otolaryngologists to reduce opioid overprescription and abuse.
Die effektive Konjugationslänge ist für die spektrale Verschiebung im rot/grün schaltenden Cyanobakteriochrom Slr1393g3 verantwortlich
Authors: Wiebeler Christian , Rao Aditya G. , Gärtner Wolfgang , Schapiro Igor
Published: December 2018

Der Ursprung der spektralen Verschiebung in dem von rot zu grün schaltenden Cyanobakteriochrom Slr1393g3 wurde durch Verwendung von kombinierten quantenmechanischen/molekularmechanischen Simulationen identifiziert. Dieses Protein, das mit klassischen Phytochromen verwandt ist, trägt das offenkettige Tetrapyrrolderivat Phycocyanobilin als Chromophor. Unsere Rechnungen zeigen, dass die effektive Konjugationslänge im Chromophor nach Isomerisierung von rot‐ zu grün‐absorbierender Form kürzer wird. Dies ist durch das Ausmaß der Planarität im gesamten Chromophor bedingt. Große Verdrillungen finden sich für die terminalen Pyrrol‐Ringe A und D. Interessanterweise trägt der D‐Ring stärker zur Farbabstimmung des Photoprodukts bei, obwohl die Verdrillung des A‐Rings größer wird. Da unsere Rechnungen zeigen, dass es bevorzugt die Verdrillung des D‐Rings ist, die die Absorption des Photoprodukts reguliert, können Mutationen vorgeschlagen werden, die die D‐Ring‐Verdrillung beeinflussen, um zu einer vorhersagbaren Absorption des Photoprodukts zu gelangen und somit Cyanobakteriochrome für biotechnologische Anwendungen wie Optogenetik und Bioimaging, maßzuschneidern.
Photoactivated Colibactin Probes Induce Cellular DNA Damage
Authors: Moodie Lindon W. K. , Hubert Madlen , Zhou Xin , Albers Michael F. , Lundmark Richard , Wanrooij Sjoerd , Hedberg Christian
Published: December 2018

Colibactin is a small molecule produced by certain bacterial species of the human microbiota that harbour the pks genomic island. Pks+ bacteria induce a genotoxic phenotype in eukaryotic cells and have been linked with colorectal cancer progression. Colibactin is produced in a benign, prodrug form which, prior to export, is enzymatically matured by the producing bacteria to its active form. Although the complete structure of colibactin has not been determined, key structural features have been described including an electrophilic cyclopropane motif, which is believed to alkylate DNA. To investigate the influence of the putative “warhead” and the prodrug strategy on genotoxicity, a series of photolabile colibactin probes were prepared that upon irradiation induced a pks+ like phenotype in HeLa cells. Furthermore, results from DNA cross‐linking and imaging studies of clickable analogues enforce the hypothesis that colibactin effects its genotoxicity by directly targeting DNA.
The Effective Conjugation Length Is Responsible for the Red/Green Spectral Tuning in the Cyanobacteriochrome Slr1393g3
Authors: Wiebeler Christian , Rao Aditya G. , Gärtner Wolfgang , Schapiro Igor
Published: December 2018

The origin of the spectral shift from a red‐ to a green‐absorbing form in a cyanobacteriochrome, Slr1393g3, was identified by combined quantum mechanics/molecular mechanics simulations. This protein, related to classical phytochromes, carries the open‐chain tetrapyrrole chromophore phycocyanobilin. Our calculations reveal that the effective conjugation length in the chromophore becomes shorter upon conversion from the red to the green form. This is related to the planarity of the entire chromophore. A large distortion was found for the terminal pyrrole rings A and D; however, the D ring contributes more strongly to the photoproduct tuning, despite a larger change in the twist of the A ring. Our findings implicate that the D ring twist can be exploited to regulate the absorption of the photoproduct. Hence, mutations that affect the D ring twist can lead to rational tuning of the photoproduct absorption, allowing the tailoring of cyanobacteriochromes for biotechnological applications such as optogenetics and bioimaging.
Base‐Free Iron Catalyzed Transfer Hydrogenation of Esters Using EtOH as Hydrogen Source
Authors: Farrar‐Tobar Ronald A. , Wozniak Bartosz , Savini Arianna , Hinze Sandra , Tin Sergey , de Vries Johannes G.
Published: December 2018

Herein, we report on the use of the iron pincer complex Iron‐MACHO‐BH, in the base‐free transfer hydrogenation of esters with EtOH as a hydrogen source. More than 20 substrates including aromatic and aliphatic esters and lactones were reduced affording the desired primary alcohols and diols with moderate to excellent isolated yields. It is also possible to reduce polyesters to the diols with this method, enabling a novel way of plastic recycling. Reduction of the renewable substrate methyl levulinate proceeds to form 1,4‐pentanediol directly. The yields are largely governed by the equilibrium between the alcohol and the ethyl ester.
Engineering Multifunctional DNA Hybrid Nanospheres through Coordination‐Driven Self‐Assembly
Authors: Li Mengyuan , Wang Congli , Di Zhenghan , Li Hui , Zhang Jingfang , Xue Wenting , Zhao Meiping , Zhang Ke , Zhao Yuliang , Li Lele
Published: December 2018

Developing simple and general approaches for the synthesis of nanometer‐sized DNA materials with specific morphologies and functionalities is important for various applications. Herein, a novel approach for the synthesis of a new set of DNA‐based nanoarchitectures through coordination‐driven self‐assembly of FeII ions and DNA molecules is reported. By fine‐tuning the assembly, Fe–DNA nanospheres of precise sizes and controlled compositions can be produced. The hybrid nanoparticles can be tailored for delivery of functional DNA to cells in vitro and in vivo with enhanced biological function. This highlights the potential of metal ion coordination as a tool for directing the assembly of DNA architectures, which conceptualizes a new pathway to expand the repertoire of DNA‐based nanomaterials. This methodology will advance both the fields of DNA nanobiotechnology and metal–ligand coordination chemistry.
Towards Unveiling the Exact Molecular Structure of Amorphous Red Phosphorus by Single‐Molecule Studies
Authors: Zhang Song , Qian Hu‐jun , Liu Zhonghua , Ju Hongyu , Lu Zhong‐yuan , Zhang Haiming , Chi Lifeng , Cui Shuxun
Published: December 2018

Since the discovery of amorphous red phosphorus (a‐red P) in 1847, many possible structures have been proposed. However, the exact molecular structure has not yet been determined because of its amorphous nature. Herein several methods are used to investigate basic properties of a‐red P. Data from scanning tunneling microscopy (STM) and gel permeation chromatography (GPC) confirm that a‐red P is a linear inorganic polymer with a broad molecular weight distribution. The theoretical single‐molecule elasticities of the possible a‐red P structures are obtained by quantum mechanical (QM) calculations. The experimental single‐molecule elasticity of a‐red P measured by single‐molecule AFM matches with the theoretical result of the zig‐zag ladder structure, indicating that a‐red P may adopt this structure. Although this conclusion needs further validation, this fundamental study represents progress towards solving the structure of a‐red P. It is expected that the strategy utilized in this work can be applied to study other inorganic polymers.
Association of Baseline Peptidylarginine Deiminase 4 Autoantibodies With Favorable Response to Treatment Escalation in Rheumatoid Arthritis
Authors: Darrah Erika , Yu Fang , Cappelli Laura C. , Rosen Antony , O'Dell James R. , Mikuls Ted R.
Published: December 2018

Objective

To determine if the baseline presence of autoantibodies to peptidylarginine deiminase 4 (PAD4) predicts therapeutic response to biologic and conventional disease‐modifying antirheumatic drugs (DMARDs) in patients with rheumatoid arthritis (RA) in whom methotrexate (MTX) monotherapy was unsuccessful.

Methods

Baseline serum from 282 RA patients in whom MTX monotherapy was unsuccessful was screened for the presence of anti‐PAD4 antibodies by immunoprecipitation. Clinical response to either triple DMARD (MTX, sulfasalazine, and hydroxychloroquine) or MTX/etanercept combination therapy was determined at 24 and 48 weeks post–treatment initiation. Disease activity was measured using the Disease Activity Score 28‐joint assessment (DAS28), and erosive disease was quantified using the Sharp/van der Heijde scoring method. Generalized estimating equations (GEEs) were used to model the clinical responses to treatment in patients with and those without baseline anti‐PAD4 antibodies.

Results

Anti‐PAD4 antibody positivity was associated with male sex, a history of never smoking, and anti–citrullinated protein antibodies. At baseline, patients with anti‐PAD4 antibodies had longer disease duration and significantly more radiographic joint damage than anti‐PAD4–negative patients, but did not differ in disease activity according to the DAS28. In unadjusted analyses and multivariable GEE models, patients with anti‐PAD4 antibodies exhibited greater improvements in DAS28 (adjusted P = 0.02 and P = 0.008, respectively) and less radiographic progression (adjusted P = 0.01 and P = 0.002, respectively) compared to anti‐PAD antibody–negative patients, independent of treatment received.

Conclusion

Although anti‐PAD4 antibodies were associated with worse baseline radiographic joint damage, suggesting a history of active or undiagnosed disease, treatment escalation therapy was more effective in reducing disease activity and slowing the progression of joint damage in this patient subset.
Comparing neural‐ and N‐gram‐based language models for word segmentation
Authors: Doval Yerai , Gómez‐Rodríguez Carlos
Published: December 2018

Word segmentation is the task of inserting or deleting word boundary characters in order to separate character sequences that correspond to words in some language. In this article we propose an approach based on a beam search algorithm and a language model working at the byte/character level, the latter component implemented either as an n‐gram model or a recurrent neural network. The resulting system analyzes the text input with no word boundaries one token at a time, which can be a character or a byte, and uses the information gathered by the language model to determine if a boundary must be placed in the current position or not. Our aim is to use this system in a preprocessing step for a microtext normalization system. This means that it needs to effectively cope with the data sparsity present on this kind of texts. We also strove to surpass the performance of two readily available word segmentation systems: The well‐known and accessible Word Breaker by Microsoft, and the Python module WordSegment by Grant Jenks. The results show that we have met our objectives, and we hope to continue to improve both the precision and the efficiency of our system in the future.
Employment of fucosidases for the synthesis of fucosylated oligosaccharides with biological potential
Authors: Guzmán‐Rodríguez Francisco , Alatorre‐Santamaría Sergio , Gómez‐Ruiz Lorena , Rodríguez‐Serrano Gabriela , García‐Garibay Mariano , Cruz‐Guerrero Alma
Published: December 2018

Fucosylated oligosaccharides play important physiological roles in humans, including in the immune response, transduction of signals, early embryogenesis and development, growth regulation, apoptosis, pathogen adhesion, and so on. Efforts have been made to synthesize fucosylated oligosaccharides, as it is difficult to purify them from their natural sources, such as human milk, epithelial tissue, blood, and so on. Within the strategies for itsin vitrosynthesis, it is remarkable the employment of fucosidases, enzymes that normally cleave the fucosyl residue from the non‐reducing end of fucosylated compounds, as these enzymes are also capable of synthesizing them by means of a transfucosylation reaction. This review summarizes the progress in the use of fucosidases for the synthesis of compounds that have potential for industrial and commercial applications.
Multiset sparse redundancy analysis for high‐dimensional omics data
Authors: Csala Attila , Hof Michel H. , Zwinderman Aeilko H.
Published: December 2018

Redundancy Analysis (RDA) is a well‐known method used to describe the directional relationship between related data sets. Recently, we proposed sparse Redundancy Analysis (sRDA) for high‐dimensional genomic data analysis to find explanatory variables that explain the most variance of the response variables. As more and more biomolecular data become available from different biological levels, such as genotypic and phenotypic data from different omics domains, a natural research direction is to apply an integrated analysis approach in order to explore the underlying biological mechanism of certain phenotypes of the given organism. We show that the multiset sparse Redundancy Analysis (multi‐sRDA) framework is a prominent candidate for high‐dimensional omics data analysis since it accounts for the directional information transfer between omics sets, and, through its sparse solutions, the interpretability of the result is improved. In this paper, we also describe a software implementation for multi‐sRDA, based on the Partial Least Squares Path Modeling algorithm. We test our method through simulation and real omics data analysis with data sets of 364,134 methylation markers, 18,424 gene expression markers, and 47 cytokine markers measured on 37 patients with Marfan syndrome.
A novel EMD mutation in a Chinese family with initial diagnosis of conduction cardiomyopathy
Authors: Zhou Junfeng , Li Hui , Li Xiangping , Li Yonggui , Yang Mei , Shi Gaoxing , Xu Danyan , Shi Xiaoliu
Published: December 2018

Introduction

Emery–Dreifuss muscular dystrophy (EDMD) is a hereditary myopathy characterized as triad of muscular dystrophy, joint contractures, and conduction cardiomyopathy. In this study, we diagnosed a X‐linked recessive EDMD patient with severe conduction cardiomyopathy while noteless muscular and joint disorders.

Methods

A Chinese cardiomyopathy family spanning four generations was enrolled in the study. Targeted next‐generation sequencing (NGS) was performed to identify the underlying mutation in the proband and validated by Sanger sequencing. Segregation analysis was applied to all 13 participants.

Results

A novel frameshift mutation (c.253_254insT, p.Y85Lfs*8) of emerin gene (EMD) was found and co‐segregated with family members. Other than the typical manifestations of X‐linked EDMD, this patient presented inconspicuous muscular disorders which were later diagnosed after the mutation been identified.

Conclusions

This study enriches the EMD gene mutation database and reminds us of the possibility of EDMD while encountering patients with severe heart rhythm defects or dilated cardiomyopathy of unknown etiology, even if they have neither obvious skeletal muscle disorder nor joint involvement.
Total MRI burden of cerebral vessel disease correlates with the progression in patients with acute single small subcortical strokes
Authors: Jiang Jingwen , Huang Xiaojun , Zhang Yu , Deng Weiping , Shen Fanxia , Liu Jianrong
Published: December 2018

Background

The patients of single small subcortical strokes (SS) commonly have neurological worsening with risk factors, and mechanisms remain unclear. Asymptomatic lacunes, white matter lesions, cerebral microbleeds, and enlarged perivascular spaces are MRI markers of cerebral small vessel disease (cSVD). Previous studies mostly explored the association between the neurological deterioration and presence of above markers separately. The relationship between progressive single small SS and the simultaneous presence of multiple markers of cSVD has not been fully identified. We aimed to investigate whether total burden of cSVD detected with MRI was associated with progressive small SS in this study.

Methods

Patients with single small SS (2.0 cm in diameter) were prospectively recruited during January 2016 and May 2018. Progression was defined as worsening by ≥1 point in National Institutes Health Stroke Scale (NIHSS) motor score within 72 hr from onset. The presence and burden of cSVD were determined by brain MRI, producing a score between 0 and 4. Besides, the patients' characteristics, clinical data, medical treatments during hospitalization stay were collected and statistically analyzed. Associations with progression were tested with forward stepwise regression analyses.

Results

Fifty‐seven (35.6%) patients underwent progression. No significant difference was observed in the distribution of any single vascular risk factor and its related laboratory data among these patients. After adjustment for age, sex, NIHSS score at admission, and time from stroke to MRI in separate models, severe WMHs (OR = 4.892; 95% CI = 2.011–11.904, p = 0.016), moderate‐ and high‐grade basal ganglia EPVS (OR = 2.970; 95% CI = 1.861–6.121, p = 0.009), and total cSVD score (OR = 3.359; 95% CI = 2.016–5.599, p = 0.010) were associated with progression.

Conclusion

This study demonstrated that total MRI cSVD burden was independently associated with progression after single small subcortical strokes.
Anesthesia for endovascular treatment in anterior circulation stroke: A systematic review and meta‐analysis
Authors: Li Xuefei , Hu Zheng , Li Qian , Guo Yinping , Xu Shabei , Wang Wei , He Dan , Luo Xiang
Published: December 2018

Background

Endovascular treatment in patients with acute anterior circulation stroke could be performed under either conscious sedation (CS) or general anesthesia (GA). Although several studies have investigated the association between the clinical outcomes and the two anesthesia methods, consensus is lacking.

Methods

PubMed and EMBASE searches were used to select full‐text articles comparing the effects of GA and CS on functional outcome and complications in patients with anterior circulation ischemic stroke. Enrolled patients were assigned to receive endovascular treatment with CS or GA, with a primary outcome of functional independency within 90 days. Secondary outcomes included intracranial hemorrhage, all‐cause mortality at 90 days, pneumonia, and intraprocedural complications.

Results

Thirteen studies (3 RCTs and 10 observational studies), which included 3,857 patients (CS = 2,129, GA = 1,728), were eligible for the analysis. The overall analysis including the RCTs and observational studies demonstrated that the functional independence within 90 days occurred more frequently among patients with CS compared with GA (OR, 1.42; 95% CI, 1.05–1.92, p = 0.02); and the risk of mortality was higher with GA compared with CS; furthermore, CS was associated with lower rate of intracranial hemorrhage. In RCTs, GA was associated with increased functional independence (OR, 0.55; 95% CI, 0.34–0.89, p = 0.01) and successful reperfusion (OR, 0.51; 95% CI, 0.30–0.89, p = 0.02).

Conclusions

In the overall analysis and observational studies, CS was associated with improved functional outcomes and relatively safe for anterior ischemic stroke compared with GA. While the pooled data from RCTs suggested that GA was associated with improved outcomes. The inconsistency indicated that more large‐scale RCTs are required to evaluate what factors influenced the effect of the anesthesia methods on clinical outcomes.
Fluorescence‐based real time monitoring and diagnostics of recombinant Pichia pastoris cultivations in a bioreactor
Authors: Karakach Tobias K. , Dachon Aurore , Choi Jerome , Miguez Carlos , Masson Luke , Tartakovsky Boris
Published: December 2018

This study describes the application of the multivariate curve resolution (MCR) analysis technique for real‐time analysis of culture fluorescence during recombinant Pichia pastoris cultivation in a bioreactor. Fluorescence spectra were acquired with an on‐line dual excitation wavelength fluorometer and then used to develop a real time MCR‐based bioprocess monitoring and diagnostics tool. Initial bioreactor experiments using two similar recombinant antibody secreting P. pastoris cell lines showed significant differences in protein production. To distinguish between the contributions of operating conditions and the specific cell line's genetic composition to the observed differences in protein production, the bioreactor experiments were repeated and accompanied by real time MCR analysis. The tests demonstrated high sensitivity of MCR‐derived “pure concentration” profiles to growth as well as to initial conditions, thus enabling real‐time cultivation process trend diagnostics and fault detection. © 2018 Her Majesty the Queen in Right of Canada © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2761, 2019.