bluuebunny/crossref_metadata_2025 huggingface dataset:
Flexible Electrochemical Bioelectronics: The Rise of In Situ Bioanalysis
Authors: Yu You , Nyein Hnin Yin Yin , Gao Wei , Javey Ali
Published: August 2019

The amalgamation of flexible electronics in biological systems has shaped the way health and medicine are administered. The growing field of flexible electrochemical bioelectronics enables the in situ quantification of a variety of chemical constituents present in the human body and holds great promise for personalized health monitoring owing to its unique advantages such as inherent wearability, high sensitivity, high selectivity, and low cost. It represents a promising alternative to probe biomarkers in the human body in a simpler method compared to conventional instrumental analytical techniques. Various bioanalytical technologies are employed in flexible electrochemical bioelectronics, including ion‐selective potentiometry, enzymatic amperometry, potential sweep voltammetry, field‐effect transistors, affinity‐based biosensing, as well as biofuel cells. Recent key innovations in flexible electrochemical bioelectronics from electrochemical sensing modalities, materials, systems, fabrication, to applications are summarized and highlighted. The challenges and opportunities in this field moving forward toward future preventive and personalized medicine devices are also discussed.
Room‐Temperature Cubic Phase Crystallization and High Stability of Vacuum‐Deposited Methylammonium Lead Triiodide Thin Films for High‐Efficiency Solar Cells
Authors: Palazon Francisco , Pérez‐del‐Rey Daniel , Dänekamp Benedikt , Dreessen Chris , Sessolo Michele , Boix Pablo P. , Bolink Henk J.
Published: August 2019

Methylammonium lead triiodide (MAPI) has emerged as a high‐performance photovoltaic material. Common understanding is that at room temperature, it adopts a tetragonal phase and it only converts to the perfect cubic phase around 50–60 °C. Most MAPI films are prepared using a solution‐based coating process, yet they can also be obtained by vapor‐phase deposition methods. Vapor‐phase‐processed MAPI films have significantly different characteristics than their solvent‐processed analogous, such as relatively small crystal‐grain sizes and short excited‐state lifetimes. However, solar cells based on vapor‐phase‐processed MAPI films exhibit high power‐conversion efficiencies. Surprisingly, after detailed characterization it is found that the vapor‐phase‐processed MAPI films adopt a cubic crystal structure at room temperature that is stable for weeks, even in ambient atmosphere. Furthermore, it is demonstrated that by tuning the deposition rates of both precursors during codeposition it is possible to vary the perovskite phase from cubic to tetragonal at room temperature. These findings challenge the common belief that MAPI is only stable in the tetragonal phase at room temperature.
Enhanced Light Utilization in Semitransparent Organic Photovoltaics Using an Optical Outcoupling Architecture
Authors: Li Yongxi , Ji Chengang , Qu Yue , Huang Xinjing , Hou Shaocong , Li Chang‐Zhi , Liao Liang‐Sheng , Guo L. Jay , Forrest Stephen R.
Published: August 2019

Building‐integrated photovoltaics employing transparent photovoltaic cells on window panes provide an opportunity to convert solar energy to electricity rather than generating waste heat. Semitransparent organic photovoltaic cells (ST‐OPVs) that utilize a nonfullerene acceptor‐based near‐infrared (NIR) absorbing ternary cell combined with a thin, semitransparent, high conductivity Cu‐Ag alloy electrode are demonstrated. A combination of optical outcoupling and antireflection coatings leads to enhanced visible transmission, while reflecting the NIR back into the cell where it is absorbed. This combination of coatings results in doubling of the light utilization efficiency (LUE), which is equal to the product of the power conversion efficiency (PCE) and the average photopic transparency, compared with a conventional semitransparent cell lacking these coatings. A maximum LUE = 3.56 ± 0.11% is achieved for an ST‐OPV with a PCE = 8.0 ± 0.2% at 1 sun, reference AM1.5G spectrum. Moreover, neutral colored ST‐OPVs are also demonstrated, with LUE = 2.56 ± 0.2%, along with Commission Internationale d'Eclairage chromaticity coordinates of CIE = (0.337, 0.349) and a color rendering index of CRI = 87.
Waterborne Fluorine‐Free Superhydrophobic Surfaces Exhibiting Simultaneous CO2 and Humidity Sorption
Authors: Baidya Avijit , Yatheendran Anagha , Ahuja Tripti , Sudhakar Chennu , Das Sarit Kumar , Ras Robin H. A. , Pradeep Thalappil
Published: August 2019

Recent progress in the field of superhydrophobic materials has proven their potential to solve many problems of the contemporary society. However, the use of such materials to capture moisture and CO2 from air, to help reduce the impact of global climate change is not explored. In addition, most of the time, fabrication of these materials needs organic solvents and fluorinated molecules involving multiple steps that hinder the use of nonwettable materials in everyday life. Herein, a waterborne, fluorine‐free, robust superhydrophobic material synthesized at room temperature through a one‐step chemical‐modification process is reported, which exhibits moisture and CO2 capturing capability. While covalently grafted low surface energy hydrocarbon molecules control the bulk superhydrophobicity, the incorporated amine functionalities facilitate moisture and CO2 adsorption as these molecules (H2O and CO2) can easily diffuse through hydrocarbon assemblies. Being polar, H2O molecules are observed to readily interact with amine groups and favor the adsorption process. Synthesized material shows an approximate CO2 adsorption of 480 ppm (10.90 mmol L−1) in ambient conditions having 75% humidity. Multifunctionality along with durability of this material will help expand the applications of superhydrophobic materials.
Buoyancy Assisted Janus Membrane Preparation by ZnO Interfacial Deposition for Water Pollution Treatment and Self‐cleaning
Authors: Pan Tian‐Di , Li Zong‐Jie , Shou Da‐Hua , Shou Wan , Fan Jin‐Tu , Liu Xuqing , Liu Yong
Published: August 2019

Water pollution, such as marine oil spill and organic chemicals pollution, is a worldwide challenge. To advance this emerging field, Janus membranes with asymmetric wettability, for oil–water separation, similitude of diode in electrocircuit, are fabricated by leveraging the buoyancy of poly(vinylidene fluoride) nanofiber on water/air interface. ZnO nanowires are in situ grown on the surface of nanofibers immersed in the solution, mimicking a nanoscale Setaria viridis structure. Such Janus membrane shows a good hydrophilicity/underwater oleophobicity on ZnO nanowires modified side and exhibits opposite hydrophobicity on the other side. Due to the side‐specific morphologies, this membrane can work either as “water‐removing” type or “oil‐removing” type filter as a diode in fluid. The membrane shows excellent permeability with the water and oil flux up to 1210 and 7653 L m−2 h−1, respectively, only driven by gravity. The durability of functional membrane is excellent and separation efficiency is higher than 97.24% after ten cycling tests. Furthermore, the hydrophilic side demonstrates an excellent photocatalytic performance over the degradation of rhodamine B dye, as self‐cleaning properties. This Janus membrane is to be an excellent candidate for wastewater remediation, both oil/water separation and organic pollutant decomposition.
Superhydrophobic, Transparent, and Stretchable 3D Hierarchical Wrinkled Film‐Based Sensors for Wearable Applications
Authors: Sahoo Bichitra Nanda , Woo Janghoon , Algadi Hassan , Lee Jaehong , Lee Taeyoon
Published: August 2019

There is currently a high demand for smart wearable and flexible electronics for high‐sensitivity strain sensors with good transparency, stretchability, and water‐repellent characteristics. The demand for such devices, especially those that demonstrate superhydrophobicity, is constantly increasing because of their prospective wearable applications. A stretchable, superhydrophobic, and transparent polydimethylsiloxane/carbon nanotube strain sensor is fabricated by directly spraying a carbon nanotube solution onto a polydimethylsiloxane nanowrinkle substrate. Applying this coating not only provides many substrate materials with a superhydrophobic surface, but also responds to stretching, bending, and torsion—properties that benefit flexible sensor applications. The strain sensor shows high optical transparency (over 70%) and displays excellent superhydrophobicity (a water contact angle of 165 ± 2°). It shows a good response, with over 5000 stretching–relaxing cycles and 10 000 cycles with twisting angles from 0° to 20°, and is able to sense strain for stretching of up to 80%, bending of up to 140°, and rotation of up to 90°. These findings demonstrate the validity of this approach for fabricating transparent superhydrophobic materials with excellent stretchability and conductivity characteristics. Such materials show great potential for wearable devices to detect human motion, including large‐scale movements, without affecting the appearance of the device.
Time‐Resolved Terahertz Spectroscopy Studies on 2D Van der Waals Materials
Authors: Han Peng , Wang Xinke , Zhang Yan
Published: August 2019

Owing to the fascinating and technologically useful electronic and optical properties, 2D van der Waals (vdW) materials are viewed as the key component for the next‐generation optoelectronic, photovoltaic, and nanoelectronic devices. Fully understanding the ultrafast carrier dynamics in 2D vdW materials is essential to study the fundamental physics and realize potential applications. Time‐resolved terahertz (THz) spectroscopy is a powerful tool used to investigate the ultrafast carrier dynamics and transport properties in semiconducting materials. In recent years, the time‐domain THz spectroscopy measurements, with or without photoexcitation on samples, are widely used to investigate the carrier dynamics of 2D vdW materials. A brief summary on the recent progress of time‐domain THz spectroscopy studies on ultrafast dynamics processes is provided. These include exciton formation and relaxation processes in semiconducting 2D materials, the relaxation of hot electrons in graphene layers, the conductivity of 2D materials modulated by femtosecond laser pulses, and their related physical properties. Finally, the physical properties of 2D vdW materials observed using the time‐domain THz spectroscopy approach are highlighted and the future challenges for time‐resolved THz spectroscopy investigations on 2D vdW materials are presented.
Bonding and Antibonding Modes in Metal–Dielectric–Metal Plasmonic Antennas for Dual‐Band Applications
Authors: Domina Kateryna L. , Khardikov Vyacheslav V. , Goryashko Vitaliy , Nikitin Alexey Y.
Published: August 2019

Resonant optical antennas supporting plasmon polaritons (SPPs)—collective excitations of electrons coupled to electromagnetic fields in a medium—are relevant to sensing, photovoltaics, and light‐emitting devices, among others. Due to the SPP dispersion, a conventional antenna of fixed geometry, exhibiting a narrow SPP resonance, cannot simultaneously operate in two different spectral bands. In contrast, here it is demonstrated that in metallic disks, separated by a nanometric spacer, the hybridized antibonding SPP mode stays in the visible range, while the bonding one can be pushed down to the mid‐infrared range. Such an SPP dimer can sense two materials of nanoscale volumes, whose fingerprint central frequencies differ by a factor of 5. Additionally, the mid‐infrared SPP resonance can be tuned by employing a phase‐change material (VO2) as a spacer. The dielectric constant of the phase‐change material is controlled by heating the material at the frequency of the antibonding optical mode. These findings open the door to a new class of optoelectronic devices able to operate in significantly different frequency ranges in the linear regime, and with the same polarization of the illuminating wave.
Giant Electric Bias‐Induced Tunability of Photoluminescence and Photoresistance in Hybrid Perovskite Films on Ferroelectric Substrates
Authors: Ren Lixia , Wang Min , Guan Xinwei , Wang Shuanhu , Yan Hong , Zhang Zhan , Yuan Guoliang , Wu Tom , Jin Kexin
Published: August 2019

Hybrid organic–inorganic perovskites represent the frontier of optoelectronic research due to their outstanding physical properties and remarkable photovoltaic performance. Despite the success of perovskite‐based photovoltaic devices, the investigation on tuning photoelectric properties of perovskites is still scarce. Here, giant modulations of photoluminescence (up to 91.3%) and photoresistance (up to 70.8%) are achieved in CH3NH3PbI3 films by applying an electric bias on single‐crystal ferroelectric Pb(Mg1/3Nb2/3)0.7Ti0.3O3 substrates. The results indicate that the electrostatic (converse piezoelectric) effect is predominant in thinner (thicker) film, resulting in rich optical and electronic tuning phenomena. This work integrates hybrid perovskites with piezoelectric platforms, paving the way toward solution‐processed piezophototronic and bias‐tunable optoelectronics.
Molecular Dynamics Simulations of the “Breathing” Phase Transformation of MOF Nanocrystallites
Authors: Keupp Julian , Schmid Rochus
Published: August 2019

The displacive phase transformation of metal‐organic frameworks (MOFs), referred to as “breathing,” is computationally investigated intensively within periodic boundary conditions (PBC). In contrast, the first‐principles parameterized force field MOF‐FF is used to investigate the thermal‐ and pressure‐induced transformations for non‐periodic nanocrystallites of DMOF‐1 (Zn2(bdc)2(dabco); bdc: 1,4‐benzenedicarboxylate; dabco: 1,4‐diazabicyclo[2.2.2]octane) as a model system to investigate the effect of the PBC approximation on the systems' kinetics and thermodynamics and to assess whether size effects can be captured by this kind of simulation. By the heating of differently sized closed pore nanocrystallites, a spontaneous opening is observed with an interface between the closed and open pore phase moving rapidly through the system. The nucleation temperature for the opening transition rises with size. By enforcing the phase transition with a distance restraint, the free energy can be quantified via umbrella sampling. The apparent barrier is substantially lower than for a concerted process under PBC. Interestingly, the barrier reduces with the size of the nanocrystallite, indicating a hindering surface effect. The results demonstrate that the actual free energy barriers and the importance of surface effects for the transformation under real conditions can only be studied beyond PBC.
Toroidal Dipole Resonances in All‐Dielectric Oligomer Metasurfaces
Authors: Zhang Guanqiao , Lan Chuwen , Gao Rui , Wen Yongzheng , Zhou Ji
Published: August 2019

Dynamic toroidal multipoles have been attracting an increasing amount of attention, thanks to their unique electromagnetic properties. The concept bears great promises in the field of optical sensing as well as electromagnetic energy localization. Metal‐based structures with specific designs have been widely adopted to obtain toroidal responses. However, applications for such structures are often hindered by the significant intrinsic loss when it comes to optical frequencies. Here, several configurations of all‐dielectric metasurfaces, in which the meta‐molecules are composed of disk oligomers (trimer, quadrumer, pentamer, and hexamer), are proposed to support toroidal dipole resonances in the near‐infrared waveband when the polarization of the normally incident excitation plane wave is directed to one of the symmetry axes of the oligomers. Multipole expansion including the toroidal dipole term along with near‐field electromagnetic patterns confirms the existence of strong toroidal dipolar responses within certain wavelength ranges. This work would enrich the diversity of the all‐dielectric optical systems with toroidal dipole resonances.
Role of staging laparoscopy for gastric cancer patients
Authors: Fukagawa Takeo
Published: August 2019

Staging laparoscopy (SL) is frequently carried out in patients with advanced gastric cancer. However, some clinical questions are being debated and consensus must be obtained. With this aim, a literature search of PubMed/MEDLINE was carried out using the keywords “gastric cancer,” “SL,” and “diagnostic laparoscopy”. Articles published online up to February 2019 were analyzed, focusing on the following questions. (i) What is an adequate indication for SL? (ii) How do you carry out SL? (iii) Does SL provide accurate information about peritoneal dissemination? (iv) Is the yield of SL different by tumor location? (v) Is SL a safe procedure? (vi) Is “repeat SL” needed? (vii) Does SL provide oncological benefit? Results provided the following responses: (i) In Western countries, clinically resectable advanced tumor is an indication for SL. Terms to be introduced for adequate indication include “location,” “type 4 (linitis feature),” “large tumor,” “equivocal computed tomography (CT] findings,” and “lymph node swelling”. (ii) Exploration of the entire peritoneal cavity is preferable. (iii) Detection rate of peritoneal disease is 43%‐52% in Japanese institutions and 7.8%‐40% in other countries. False‐negative findings during SL were 0%‐17%, and 10%‐13% when limited to cytology. (iv) Yield of SL was higher in gastric cancer compared with esophagogastric junctional tumor. (v) SL‐related complications were estimated to occur in 0.4%. (vi) Repeat SL is important after treatment. (vii) If the efficacy of neoadjuvant chemotherapy for patients with P0CY1 is established, SL can provide oncological benefit. SL can be carried out safely and effectively. Considering the prevalence of neoadjuvant treatment, the role of SL will become more important.
Carbon molecular sieving membranes for butane isomer separation
Authors: Zhou Yingwu , Wang Yuecheng , Ban Yujie , Guo Ang , Yang Kun , Cao Na , Yang Weishen
Published: August 2019

Membrane‐based separations of hydrocarbon isomers are major challenges for the petrochemical industry. Herein, high quality carbon molecular sieving membranes (CMSMs) were prepared on γ‐alumina substrates from pyrolysis of P84 polymer membranes. Targeting at butane isomer separations, we tailored the slit‐like ultramicropores of CMSMs at angstrom level by rational manipulations of the pyrolysis temperature. The crack‐free CMSMs were obtained at 600°C with the narrow and uniform ultramicropores centered at 6.0 å. A clear molecular size/shape discrimination was achieved successfully and remarkable n‐butane permeance (384 GPU) and n‐butane/iso‐butane separation factor (74) was observed, which transcends the upper limit of well‐intergrown crystalline zeolite membranes. Fine‐tuning of the membrane thickness at sub‐micron level, the n‐butane permeance and n‐butane/iso‐butane separation factor were further optimized, which shows a great potential for petrochemical separation.
Study and modeling of the liquid–solid equilibrium of the KCl–KNO3–HCl–H2O system at 283.15 K
Authors: Wang Houpeng , Zhou Zhiyong , Qin Wei , Li Yigui , Fei Weiyang
Published: August 2019

In this work, the liquid–solid equilibrium of the KCl–KNO3–HCl–H2O system at 283.15 K was investigated. To calculate the solubility product constants of KCl and KNO3 in HCl solution, the Pitzer equation was used to calculate the activity coefficient of the ionic species in aqueous solution. In addition, the thermodynamic model with the Pitzer equation was constructed to regress the temperature coefficient parameters for HCl and HNO3. The calculation and prediction of the KCl–KNO3–HCl–H2O system using the results of the regression confirmed that the regression was successful and the Pitzer equation was suitable. For the reaction KCl(s) + HNO3 → KNO3(s) + HCl, the equilibrium constant K can be obtained from the solubility product constants of KCl and KNO3. Eutectic points for the KCl–KNO3–HCl–H2O system were also predicted. These equilibrium data could be expressed by the triangular phase diagram. The process of the reaction to produce KNO3 could be explained through this triangular phase.
Continuous ion‐selective separations by shock electrodialysis
Authors: Conforti Kameron M. , Bazant Martin Z.
Published: August 2019

Water purification remains a challenge across sectors worldwide, especially the efficient removal of specific (toxic or valuable) dissolved ions at low salinity. In this article, shock electrodialysis (SED) is shown for the first time to have this capability, by demonstrating continuous separation of magnesium ions from aqueous mixtures of NaCl and MgCl2. By systematically measuring the composition of all input and output streams, the mechanisms that drive selectivity, current efficiency, and desalination are revealed, as well as strategies to improve performance. For solutions initially rich in sodium, highly selective (> 98%) continuous removal of magnesium can be achieved with only moderate (50–70%) total salt removal. This remarkable selectivity is associated with super‐diffusive ion transport, mediated by charged double layers in a porous glass frit, behind a steady deionization shockwave in cross flow.
A graphene oxide membrane with self‐regulated nanochannels for the exceptionally stable bio‐oil dehydration
Authors: Li Gang , Ma Shanhong , Yang He , Fan Shuanshi , Lang Xuemei , Wang Yanhong , Li Wentao , Liu Yuanzhi , Zhou Liang
Published: August 2019

The transport behaviors and nanochannel structures of a graphene oxide (GO) membrane were studied for pervaporation dehydration of bio‐oil with a high acidity and a complex composition. The GO membrane showed an unprecedentedly stable water flux of approximately 0.43 kg m−2 hr−1, with a water content of 97 wt% in the permeate throughout 70 hr of pervaporation testing at 30°C. Both the calculated activation energy for water permeation and X‐ray diffraction characterization results confirmed that the nanochannel structures of the GO membrane were temperature‐ and liquid media‐responsive. The molecular intercalation‐induced self‐regulation of the size of laminar nanochannels in the GO membrane was suggested to be primarily responsible for the significantly reduced membrane fouling and the exceptionally stable pervaporation performance for the GO membrane. The mechanistic insights into the nanochannel structures and antifouling properties would provide important inspiration for the design of novel highly fouling‐resistant membrane materials for practical applications.
Metabolic engineering of Bacillus subtilis for high‐titer production of menaquinone‐7
Authors: Yang Shaomei , Wang Yongping , Cai Zhigang , Zhang Guoyin , Song Hao
Published: August 2019

Menaquinone‐7 (MK‐7) is a member of vitamin K2 used for prevention from osteoporosis and cardiovascular calcification. This study constructed Bacillus subtilis strains for high‐titer production of MK‐7 through metabolic engineering approaches. In B. subtilis, MK‐7 biosynthesis was categorized into five modules: glycerol dissociation pathway, shikimate pathway, pyrimidine metabolic pathway, methylerythritol phosphate pathway, and MK‐7 pathway. Overexpression of GlpK and GlpD (glycerol dissociation pathway) led to a ~10% increase in the MK‐7 titer. Deletion of the genes mgsA and araM increased the MK‐7 production by 15%. Furthermore, overexpression of AroGD146N (shikimate pathway), PyrGE156K (pyrimidine metabolic pathway), HepS (methylerythritol phosphate pathway), and VHb could also increase the MK‐7 titer. Finally, we obtained a recombinant strain BSMK_11 with simultaneous overexpressing the genes glpK, glpD, aroG
fbr, pyrG
fbr, hepS, vgb, and knockouting the genes mgsA and araM, and the MK‐7 titer reached 281.4 ± 5.0 mg/L (i.e., 12.0 mg/g DCW) in a 5 L fermenter.
Development of a filtered interphase heat transfer model based on fine‐grid simulations of gas–solid flows
Authors: Huang Zheqing , Zhang Chi , Jiang Ming , Zhou Qiang
Published: August 2019

The filtered interphase heat‐transfer coefficient for coarse‐grid simulations of gas–solid flows can be obtained via a correction (Q) to its microscopic counterpart. The numerical results show that a good linear correlation between Q and the subgrid drift temperature exists at various filtered solid volume fractions, filter sizes and Reynolds numbers, where the subgrid drift temperature is the correlation between the fluctuating temperature of the gas phase and the fluctuation of the gas volume fraction. Since Q can be determined solely by one subgrid quantity, closure for Q is directly pursued. It is found that Q correlates surprisingly well with the product of the filtered solid volume fraction and the filtered temperature difference between the two phases normalized by the filtered heat transfer at a larger scale than the considered coarse grid. A fitting correlation is formulated based on this observation, and its predictability is evaluated in an a priori test.
A comparison of different geometrical elements to model fluid wicking in paper‐based microfluidic devices
Authors: Boodaghi Miad , Shamloo Amir
Published: August 2019

Recently, microfluidic paper‐based analytical devices (μPADs) have outstripped polymeric microfluidic devices in the ease of fabrication and simplicity. Surface tension‐based fluid motion in the paper's porous structure has made the paper a suitable substrate for multiple biological assays by directing fluid into multiple assay zones. The widespread assumption in most works for modeling wicking in a paper is that the paper is a combination of capillaries with the same diameter equal to the effective pore diameter. Although assuming paper as a bundle of capillaries gives a good insight into pressure force that drives the fluid inside the paper, there are some difficulties using the effective pore radius. The effective pore radius is totally different from the average geometrical pore radius which makes it impossible to predict wicking in μPADs based on geometrical parameters. In this article, we introduce different analytical and numerical models to investigate the possibility of determining the permeability of the paper, based on geometrical parameters rather than effective parameters. The lattice Boltzmann method is used for numerical simulations. The permeability of each of the proposed models was compared with the experimental permeability. Results indicated that assuming paper as a combination of capillaries and annuluses leads to accurate results that totally depend on average geometrical values rather than effective values. This paves the way for prediction of the fluid wicking only by considering average geometrical pore and fiber diameters.
6‐Methylenebicyclo[3.2.1]oct‐1‐en‐3‐one: A Twisted Olefin as Diels–Alder Dienophile for Expedited Syntheses of Four Kaurane Diterpenoids
Authors: Wang Junjie , Ma Dawei
Published: August 2019

6‐Methylenebicyclo[3.2.1]oct‐1‐en‐3‐one, a twisted and highly reactive enone, was prepared for the first time by elimination of its bromide precursor. Its reactions as a dienophile with several dienes in Diels–Alder reactions proceeded smoothly to provide tricyclic and tetracyclic adducts, which allowed short syntheses (10–11 steps) of four kurane diterpenoids including 11β‐hydroxy‐16‐kaurene, 11α‐hydroxy‐16‐kaurene, liangshanin G, and gesneroidin B.
Atomic Layer Deposition of ZnO on CuO Enables Selective and Efficient Electroreduction of Carbon Dioxide to Liquid Fuels
Authors: Ren Dan , Gao Jing , Pan Linfeng , Wang Zaiwei , Luo Jingshan , Zakeeruddin Shaik M. , Hagfeldt Anders , Grätzel Michael
Published: August 2019

Electrochemical reduction of carbon dioxide, if powered by renewable electricity, could serve as a sustainable technology for carbon recycling and energy storage. Among all the products, ethanol is an attractive liquid fuel. However, the maximum faradaic efficiency of ethanol is only ≈10 % on polycrystalline Cu. Here, CuZn bimetallic catalysts were synthesized by in situ electrochemical reduction of ZnO‐shell/CuO‐core bi‐metal‐oxide. Dynamic evolution of catalyst was revealed by STEM‐EDS mapping, showing the migration of Zn atom and blending between Cu and Zn. CuZn bimetallic catalysts showed preference towards ethanol formation, with the ratio of ethanol/ethylene increasing over five times regardless of applied potential. We achieved 41 % faradaic efficiency for C2+ liquids with this catalyst. Transitioning from H‐cell to an electrochemical flow cell, we achieved 48.6 % faradaic efficiency and −97 mA cm−2 partial current density for C2+ liquids at only −0.68 V versus reversible hydrogen electrode in 1 m KOH. Operando Raman spectroscopy showed that CO binding on Cu sites was modified by Zn. Free CO and adsorbed *CH3 are believed to combine and form *COCH3 intermediate, which is exclusively reduced to ethanol.
Construction of C(sp2)−C(sp3) Bond between Quinoxalin‐2(1H)‐ones and N‐Hydroxyphthalimide Esters via Photocatalytic Decarboxylative Coupling
Authors: Yan Zhiyang , Sun Bin , Zhang Xun , Zhuang Xiaohui , Yang Jin , Su Weike , Jin Can
Published: August 2019

A novel visible‐light‐driven decarboxylative coupling of alkyl N‐hydroxyphthalimide esters (NHP esters) with quinoxalin‐2(1H)‐ones has been developed. This C(sp2)−C(sp3) bond‐forming transformation exhibits excellent substrate generality with respect to both the coupling partners. Of note, a series of 3‐primary alkyl‐substituted quinoxalin‐2(1H)‐ones that were difficult to synthesize by previous methods could be obtained in moderate to excellent yields. Additionally, the mild conditions, easy availability of substrates, wide functional group tolerance and operational simplicity make this protocol practical in the synthesis of 3‐alkylated quinoxalin‐2(1H)‐ones.
Wider Voltage Window, High Capacity and Ultra‐Long Life of an Na0.91MnO2 Cathode for an Aqueous High‐Performance Supercapacitor
Authors: Qin Tianfeng
Published: August 2019

The potential window of an aqueous supercapacitor cathode is usually less than 1.3 V, which hinders the enhancement of the energy density and can be conquered by activating the multiple redox reactions of the cathode. Herein, tetragonal phase Na0.91MnO2 nanosheets/nanowires arrays with high cation content are produced in situ on an electrochemically treated carbon cloth by an electrochemical oxidation method. It is observed that the Na0.91MnO2 nanosheet/nanowire array electrode can operate stably within the potential window of −0.6 V to 1.2 V (vs Ag/AgCl) with an ultrahigh capacity of 856 C g−1 and an outstanding stability and excellent rate ability. With a carbon fiber fabric with a large surface area as the anode, the Na0.91MnO2 cathode in the two‐electrode cell can still operate stably within the voltage range from 0 to 2.07 V (still within the range of the three redox peak couples, demonstrating a high energy density of 138 Wh kg−1, an excellent power density of 33 kW kg−1 as well as 100 % retention even after 120 000 cycles. This work may pave the way for the development of an aqueous supercapacitor cathode with a wider potential window.
An Unintentional Discovery of a Fluorogenic DNA Probe for Ribonuclease I
Authors: Chang Dingran , Chang Thomas , Salena Bruno , Li Yingfu
Published: August 2019

Ribonuclease I belongs to a class of nonspecific endoribonucleases and plays many important roles in a variety of biological and cellular processes. While their ubiquitous nature and high activity contribute to the well‐known problem of RNase contamination in experimentation, their abundance in bacteria can potentially be leveraged as a biosensor target. As a result, there is substantial interest in generating a specific and reliable probe for RNase detection for a variety of purposes. To that end, we report on our unintentional discovery of the RNase I probe RFA13‐1 isolated through in vitro selection with the crude extracellular mixture from Clostridium difficile contaminated with Klebsiella aerogenes as a selection target. Characterization of RFA13‐1 reveals that it exhibits high sensitivity to Escherichia coli RNase I with a detection limit of 1.39 pm. Furthermore, RFA13‐1 also shows high specificity for RNase I produced only in select bacteria from the Enterobacteriaceae family. As a result, this probe offers a simple tool for RNase I detection with potential applications in RNase functional studies, ribonuclease contamination monitoring, and bacterial detection.
Steric Effects Dictate the Formation of Terminal Arylborylene Complexes of Ruthenium from Dihydroboranes
Authors: Lenczyk Carsten , Roy Dipak Kumar , Nitsch Jörn , Radacki Krzysztof , Rauch Florian , Dewhurst Rian D. , Bickelhaupt F. Matthias , Marder Todd B. , Braunschweig Holger
Published: August 2019

The steric and electronic properties of aryl substituents in monoaryl borohydrides (Li[ArBH3]) and dihydroboranes were systematically varied and their reactions with [Ru(PCy3)2HCl(H2)] (Cy: cyclohexyl) were studied, resulting in bis(σ)‐borane or terminal borylene complexes of ruthenium. These variations allowed for the investigation of the factors involved in the activation of dihydroboranes in the synthesis of terminal borylene complexes. The complexes were studied by multinuclear NMR spectroscopy, mass spectrometry, X‐ray diffraction analysis, and density functional theory (DFT) calculations. The experimental and computational results suggest that the ortho‐substitution of the aryl groups is necessary for the formation of terminal borylene complexes.
Facile Synthesis of Ultra‐Small Few‐Layer Nanostructured MoSe2 Embedded on N, P Co‐Doped Bio‐Carbon for High‐Performance Half/Full Sodium‐Ion and Potassium‐Ion Batteries
Authors: Zeng Lingxing , Kang Biyu , Luo Fenqiang , Fang Yixing , Zheng Cheng , Liu Junbin , Liu Renpin , Li Xinye , Chen Qinghua , Wei Mingdeng , Qian Qingrong
Published: August 2019

Sodium/potassium‐ion batteries (SIBs/PIBs) arouse intensive interest on account of the natural abundance of sodium/potassium resources, the competitive cost and appropriate redox potential. Nevertheless, the huge challenge for SIBs/PIBs lies in the scarcity of an anode material with high capacity and stable structure, which are capable of accommodating large‐size ions during cycling. Furthermore, using sustainable natural biomass to fabricate electrodes for energy storage applications is a hot topic. Herein, an ultra‐small few‐layer nanostructured MoSe2 embedded on N, P co‐doped bio‐carbon is reported, which is synthesized by using chlorella as the adsorbent and precursor. As a consequence, the MoSe2/NP‐C‐2 composite represents exceedingly impressive electrochemical performance for both sodium‐ion batteries (SIBs) and potassium‐ion batteries (PIBs). It displays a promising reversible capacity (523 mAh g−1 at 100 mA g−1 after 100 cycles) and impressive long‐term cycling performance (192 mAh g−1 at 5 A g−1 even after 1000 cycles) in SIBs, which are some of the best properties of MoSe2‐based anode materials for SIBs to date. To further probe the great potential applications, full SIBs pairing the MoSe2/NP‐C‐2 composite anode with a Na3V2(PO4)3 cathode also exhibits a satisfactory capacity of 215 mAh g−1 at 500 mA g−1 after 100 cycles. Moreover, it also delivers a decent reversible capacity of 131 mAh g−1 at 1 A g−1 even after 250 cycles for PIBs.
Isolation of Carbene‐Stabilized Arsenic Monophosphide [AsP] and its Radical Cation [AsP]+. and Dication [AsP]2+
Authors: Doddi Adinarayana , Bockfeld Dirk , Zaretzke Marc‐Kevin , Bannenberg Thomas , Tamm Matthias
Published: August 2019

Arsenic monophosphide (AsP) species supported by two different N‐heterocyclic carbenes were prepared by reaction of (IDipp)PSiMe3 (1) (IDipp=1,3‐bis(2,6‐diisopropylphenyl)imidazolin‐2‐ylidene) with (IMes)AsCl3 (2) (IMes=1,3‐bis(2,4,6‐trimethylphenyl)imidazolin‐2‐ylidene) to afford the dichloride [(IMes)As(Cl)P(IDipp)]Cl (3), which upon reduction with KC8 furnished heteroleptic [(IMes)AsP(IDipp)] (4). The corresponding mono‐ and dications [(IMes)AsP(IDipp)][PF6], [5]PF6, and [(IMes)AsP(IDipp)][GaCl4]2, [6][GaCl4]2, respectively, were prepared by one‐electron oxidation of 4 with ferrocenium hexafluorophosphate, [Fc]PF6, or by chloride abstraction from 3 with two equivalents of GaCl3, respectively. Compounds 4–6 represent rare examples of heterodiatiomic interpnictogen compounds, and X‐ray crystal structure determinations together with density functional theory (DFT) calculations reveal a consecutive shortening of the As−P bond lengths and increasing bond order, in agreement with the presence of an arsenic–phosphorus single bond in 4 and a double bond in 62+. The EPR signal of the cationic radical [5]+. indicates a symmetric spin distribution on the AsP moiety through strong hyperfine coupling with the 75As and 31P nuclei.
Morphological and molecular motifs of fibrosing pulmonary injury patterns
Authors: Jonigk Danny , Stark Helge , Braubach Peter , Neubert Lavinia , Shin Hoen‐oh , Izykowski Nicole , Welte Tobias , Janciauskiene Sabina , Warnecke Gregor , Haverich Axel , Kuehnel Mark , Laenger Florian
Published: August 2019

Interstitial lung diseases encompass a large number of entities, which are characterised by a small number of partially overlapping fibrosing injury patterns, either alone or in combination. Thus, the presently applied morphological diagnostic criteria do not reliably discriminate different interstitial lung diseases. We therefore analysed critical regulatory pathways and signalling molecules involved in pulmonary remodelling with regard to their diagnostic suitability. Using laser‐microdissection and microarray techniques, we examined the expression patterns of 45 tissue‐remodelling associated target genes in remodelled and non‐remodelled tissue samples from patients with idiopathic pulmonary fibrosis/usual interstitial pneumonia (IPF/UIP), non‐specific interstitial pneumonia (NSIP), organising pneumonia (OP) and alveolar fibroelastosis (AFE), as well as controls (81 patients in total). We found a shared usage of pivotal pathways in AFE, NSIP, OP and UIP, but also individual molecular traits, which set the fibrosing injury patterns apart from each other and correlate well with their specific morphological aspects. Comparison of the aberrant gene expression patterns demonstrated that (1) molecular profiling in fibrosing lung diseases is feasible, (2) pulmonary injury patterns can be discriminated with very high confidence on a molecular level (86–100% specificity) using individual gene subsets and (3) these findings can be adapted as suitable diagnostic adjuncts.
Achieving Mucosal Healing in Inflammatory Bowel Diseases: Which Drug Concentrations Need to Be Targeted?
Authors: Van den Berghe Nathalie , Gils Ann , Thomas Debby
Published: August 2019

Biologicals introduced a major shift in the treatment of patients suffering from inflammatory bowel diseases. Despite providing a tight disease control for many patients, a considerable proportion of patients will fail to respond favorably to treatment or will lose response over time. Therapeutic drug monitoring emerged as a valuable tool to guide clinical decision making as serum drug concentrations have been linked to outcomes. Focusing on mucosal healing as the ultimate treatment goal, different drug concentration thresholds to achieve this outcome have been identified in the literature and are summarized in this review. For therapeutic drug monitoring to be successful in guiding clinical decision making, the used assay, the sampling time point, and the outcome that is aimed for should be taken into account when interpreting drug concentration thresholds. Awareness of these essential aspects among clinicians will improve the implementation of therapeutic drug monitoring and aid in making an evidence‐based decision.
Cobalt‐Tungsten Bimetallic Carbide Nanoparticles as Efficient Catalytic Material for High‐Performance Lithium–Sulfur Batteries
Authors: Zhao Pengfei , Zhang Ze , He Haoxuan , Yu Yinghui , Li Xiao , Xie Weicheng , Yang Zhenyu , Cai Jianxin
Published: August 2019

Lithium–sulfur (Li–S) batteries are promising candidates for next‐generation energy storage devices owing to their advantages such as high theoretical specific capacity and energy density. However, the shuttle effect of polysulfide intermediates and the slow electrochemical kinetics have a severe passive effect on the cycling stability and rate performance. A Co3W3C@C composite was prepared through a simple one‐pot pyrolysis method and used as a modifying layer on a commercial separator. The obtained modified separator not only prevented the shuttle effect through both strong chemical interaction and a physical barrier toward polysulfides, but also acted as a catalytic membrane to catalyze the electrochemical redox of active sulfur species. By employing the coated separator, the cathode with 60 wt % sulfur delivered a high initial capacity of 1345 mAh g−1 at 0.1 A g−1, excellent rate performance with a high capacity of 670 mAh g−1 even at 7 A g−1, and outstanding cycle performance with a low decay rate of 0.06 % per cycle and an average Coulombic efficiency of 99.3 % within 500 cycles at 1 A g−1. Even at a sulfur loading of 3 mg cm−1, a high initial capacity of 869 mAh g−1 and 632 mAh g−1 after 200 cycles at 1 A g−1 were obtained. The results demonstrate the advantages of Co–W bimetallic carbide in preventing the shuttle effect and promoting the redox kinetics for high performance Li–S batteries.
Cytological diagnosis of juvenile xanthogranuloma: A rare histiocytic disorder
Authors: Chauhan Shivangi , Diwaker Preeti , Singh Aakanksha , Gogoi Priyanka , Arora Vinod K.
Published: August 2019

Juvenile xanthogranuloma (JXG) is a rare type of non‐Langerhan cell histiocytic disorder, which is mostly confined to skin of head and neck. It is a self‐limiting benign condition, which does not require surgery. We present a case of 8‐month‐old girl child with multiple yellowish brown colored papules over scalp, face, and neck. A clinical diagnosis of cutaneous mastocytosis was made. Fine‐needle aspiration cytology (FNAC) smears showed foamy macrophages along with mixed inflammatory infiltrate and few touton giant cells. A diagnosis of JXG was rendered which was confirmed on histopathology and immunohistochemistry.Juvenile xanthogranuloma can be diagnosed on FNAC based on its characteristic cytologic features; however, it requires a high index of suspicion by cytopathologist. Cytological diagnosis of JXG can save the patient from unnecessary surgical biopsy or excision.
High‐definition transcranial direct current stimulation in anorexia nervosa: A pilot study
Authors: Phillipou Andrea , Kirkovski Melissa , Castle David J. , Gurvich Caroline , Abel Larry A. , Miles Stephanie , Rossell Susan L.
Published: August 2019

Objective

Anorexia nervosa (AN) is a serious psychiatric condition often associated with poor outcomes. Biologically informed treatments for AN, such as brain stimulation, are lacking, in part due to the unclear nature of the neurobiological contributions to the illness. However, recent research has suggested a specific neurobiological target for the treatment of AN, namely stimulation of the inferior parietal lobe (IPL). The aim of this study was to stimulate—noninvasively—the left IPL in individuals with AN using high‐definition transcranial direct current stimulation (HD‐tDCS).

Method

Twenty participants will be randomized to receive 10 daily sessions of HD‐tDCS or sham HD‐tDCS (placebo). Assessments will be carried out at baseline and end point, as well as 4‐ and 12‐week follow‐ups.

Discussion

This pilot investigation will primarily determine the feasibility and acceptability of this intervention.
Dynamic changes in DNA methylation during embryonic and postnatal development of an altricial wild bird
Authors: Watson Hannah , Salmón Pablo , Isaksson Caroline
Published: August 2019

DNA methylation could shape phenotypic responses to environmental cues and underlie developmental plasticity. Environmentally induced changes in DNA methylation during development can give rise to stable phenotypic traits and thus affect fitness. In the laboratory, it has been shown that the vertebrate methylome undergoes dynamic reprogramming during development, creating a critical window for environmentally induced epigenetic modifications. Studies of DNA methylation in the wild are lacking, yet are essential for understanding how genes and the environment interact to affect phenotypic development and ultimately fitness. Furthermore, our knowledge of the establishment of methylation patterns during development in birds is limited. We quantified genome‐wide DNA methylation at various stages of embryonic and postnatal development in an altricial passerine bird, the great tit Parus major. While, there was no change in global DNA methylation in embryonic tissue during the second half of embryonic development, a twofold increase in DNA methylation in blood occurred between 6 and 15 days posthatch. Though not directly comparable, DNA methylation levels were higher in the blood of nestlings compared with embryonic tissue at any stage of prenatal development. This provides the first evidence that DNA methylation undergoes global change during development in a wild bird, supporting the hypothesis that methylation mediates phenotypic development. Furthermore, the plasticity of DNA methylation demonstrated during late postnatal development, in the present study, suggests a wide window during which DNA methylation could be sensitive to environmental influences. This is particularly important for our understanding of the mechanisms by which early‐life conditions influence later‐life performance. While, we found no evidence for differences in genome‐wide methylation in relation to habitat of origin, environmental variation is likely to be an important driver of variation in methylation at specific loci.
The Bellerophon pipeline, improving de novo transcriptomes and removing chimeras
Authors: Kerkvliet Jesse , de Fouchier Arthur , van Wijk Michiel , Groot Astrid Tatjana
Published: August 2019

Transcriptome quality control is an important step in RNA‐Seq experiments. However, the quality of de novo assembled transcriptomes is difficult to assess, due to the lack of reference genome to compare the assembly to. We developed a method to assess and improve the quality of de novo assembled transcriptomes by focusing on the removal of chimeric sequences. These chimeric sequences can be the result of faulty assembled contigs, merging two transcripts into one. The developed method is incorporated into a pipeline, which we named Bellerophon, that is broadly applicable and easy to use. Bellerophon first uses the quality assessment tool TransRate to indicate the quality, after which it uses a transcripts per million (TPM) filter to remove lowly expressed contigs and CD‐HIT‐EST to remove highly identical contigs. To validate the quality of this method, we performed three benchmark experiments: (1) a computational creation of chimeras, (2) identification of chimeric contigs in a transcriptome assembly, (3) a simulated RNA‐Seq experiment using a known reference transcriptome. Overall, the Bellerophon pipeline was able to remove between 40% and 91.9% of the chimeras in transcriptome assemblies and removed more chimeric than nonchimeric contigs. Thus, the Bellerophon sequence of filtration steps is a broadly applicable solution to improve transcriptome assemblies.
Structure and Properties of the Non‐Centrosymmetric Manganese(II) Borate Mn5(BO3)3OH
Authors: Falkowski Viktoria , Zeugner Alexander , Bayarjargal Lkhamsuren , Saxer Andreas , Ruck Michael , Huppertz Hubert
Published: August 2019

The rose‐colored compound Mn5(BO3)3OH was synthesized under high‐pressure/high‐temperature conditions of 2.5 GPa and 973 K in a Walker‐type multianvil press. Single‐crystal X‐ray structure determination yielded the non‐centrosymmetric monoclinic space group Pm (no. 6) with the lattice parameters a = 329.71(1), b = 1384.92(5), c = 902.37(3) pm, and β = 107.92(1)°. The presence of the hydroxide group is ascertained by vibrational spectroscopy. Magnetization experiments in the range from 300 to 14 K revealed paramagnetic behavior with antiferromagnetic ordering below 14 K and an effective magnetic moment of 12.2 µB per formula unit. The acentric nature of the material was verified by second harmonic generation measurements, yielding a considerably strong intensity (Isample/Iquartz = 11.14). Additionally, thermal investigations showed a several‐step transformation to Mn2OBO3 upon heating under air.