bluuebunny/crossref_metadata_2025 huggingface dataset:
Gulf Cooperation Council (GCC)—Energy Price Reforms in the GCC—What Can Be Learned From International Experiences?
Authors:   International Monetary Fund
Published: August 2019

Energy prices in the GCC countries are low by international standards. These low prices have co-existed with rapid economic development in the region over the past 50 years, but the costs of this policy have also risen in terms of very high energy usage per capita. Providing energy at low prices has also effectively absorbed resources that could otherwise have been invested in human and physical capital or saved for future generations. The implicit cost of low energy prices in the GCC, in terms of foregone revenue, is estimated to be around 5 percent of GDP (about 8 percent of non-oil GDP) this year.

GCC countries have been embarking on energy price reform in recent years. The recent decision of the UAE to remove fuel subsidies is an important initiative. Nevertheless, energy prices are generally still below international levels and differ substantially across the GCC countries. In most countries, further steps are needed to raise energy prices to reduce the growth in energy consumption and to support the fiscal adjustment that is necessary in the current lower oil price environment.

Evidence in this paper suggests the inflationary impact of higher energy prices in the GCC is likely to be small, and while there may be some adverse effect on growth in the near-term, over the longer-term the growth benefits should be positive. Given the low weight of energy products in the CPI, first round effects of higher energy prices should be limited, while well anchored inflation expectations should help prevent second-round effects. On growth, a gradual increase in energy prices should have a manageable impact on industrial activity, although energy intensive industries will be adversely affected and will need to adjust. In the longer-term energy price reforms could generate significant permanent real income gains for the economy as a whole.

More broadly, international experiences suggest that the likelihood of success with energy price reforms increases if the reforms are:
Strengthening the Framework for Post Program Monitoring
Authors:   International Monetary Fund
Published: August 2019

Post-Program Monitoring (PPM) is an important part of the Fund’s safeguards architecture. It provides a framework for closer engagement with members that have substantial outstanding Fund credit but are no longer in a program relationship, and helps identify risks and provide advice on policies that will assist these members in repaying the Fund. The significant expansion in Fund credit since the global financial crisis, much of it through medium-term financing of members with high access levels, puts a premium on this form of monitoring. The design and implementation of the current policy can be strengthened.
New Common Evaluation Framework for IMF Capacity Development
Authors:   International Monetary Fund
Published: August 2019

new common evaluation framework for the Fund’s capacity development (CD) activities. The new common evaluation framework is intended to streamline current practices and increase comparability and use of results by adopting for all CD evaluations a common four-step process that includes use of the OECD Development Assistance Committee (DAC) evaluation criteria. Around this common approach, there is flexibility to adapt evaluations to reflect the wide range of CD activities. Key elements of the framework are grouped around the objectives of: producing shorter, more focused, and more comparable evaluations; improving the information supporting evaluations;spending the same level of resources on evaluations while allocating these scarce resources more efficiently; and using the information from evaluations to alter practices or shift the targeting of CD resources.
Approaches to Macrofinancial Surveillance in Article IV Reports
Authors:   International Monetary Fund
Published: August 2019

The Fund has made good progress over the past two years in integrating macrofinancial analysis into Article IV surveillance for a wide range of members. Building on past work to enhance financial sector analysis, Fund staff has sought to develop a consistent and forward-looking view on how the financial sector affects each member’s economic outlook with the aim of strengthening staff’s capacity to provide advice on macro-critical questions.

The focus has been on developing a fuller understanding of macrofinancial linkages, and applying this analysis to inform policy advice. Staff has sought to articulate the role of the financial sector in the macroeconomic baseline, and to integrate the financial sector into the risk assessment, taking into account both the impact of macro shocks on the financial sector as well as the effect of financial shocks on macroeconomic stability. Strengthening the analytical foundations of this work has helped staff provide advice in all policy areas, including financial sector policies.

Staff has tailored macrofinancial analysis to the circumstances of a diverse set of economies. Area departments have taken the lead in selecting 66 economies for enhanced macrofinancial coverage and in identifying topics, drawing on targeted support from functional departments. The choice of coverage has included legacies from the global financial crisis—such as deleveraging and stretched balance sheets in advanced economies and some emerging markets—and more recent challenges such as commodity price shocks, especially in low income countries, and the risks of housing booms. The financial sector’s contribution to growth and inclusion has become an important question in countries across all income groups.

Staff sees benefits in mainstreaming this approach across the membership, while continuing to address analytical gaps and adapting to new challenges. The work of the past two years has underscored the criticality of macrofinancial analysis for a diverse range of members, and laid the basis for progressively mainstreaming macrofinancial surveillance across the membership. Building on this progress, staff sees scope for the Fund to deepen its understanding of the macroeconomic effects of financial shocks, to better adapt microprudential and macroprudential policy advice with an assessment of macro-critical risks including systemic risk, and to deepen the analysis of outward spillovers. Staff will also need to continue to adapt the focus of analysis and tools, and seek relevant data, as economic challenges evolve.
Influence of degree of crystallinity on DC-conduction of polypropylene
Authors: Laihonen Sari J , Greijer Helena
Published: August 2019

Aim of this work was to study how degree of crystallinity influences the DC conduction characteristics of capacitor grade polypropylene (PP). PP pellets were pressed to 0.3 mm plates using two different cooling rates in order to vary the degree of crystallinity. The DC conduction currents were measured at 50 and 70 °C at 8-55 kV/mm. 3 h polarization and 15 h depolarization times were used. It turned out that temperature and the dielectric stress played a more dominant role regarding DC-conductivity than the obtained ~4 wt-% difference in crystallinity. Especially at 39-55 kV/mm, when temperature increased from 50 to 70 °C the DC-conductivity increased 10-15 times. There was however a trend related to the degree of crystallinity: the increase in crystallinity (more slowly sample cooling) led to lower conductivity values.
Time-Dependent Electric Field Distribution in Layered Paper-Oil Insulation
Authors: Håkonseth Gunnar , Ildstad Erling
Published: August 2019

Layered paper–oil insulation is used in several types of HVDC equipment. In order to better understand breakdown mechanisms and optimize the design, it is important to understand the electric field distribution in the insulation. In the present work, a test object with such insulation has been modeled as a series connection of oil and impregnated paper. The permittivity, conductivity, and the dielectric response function has been measured for impregnated paper and oil separately and used as parameters in a dielectric response model for the layered insulation system. A system of differential equations has been established describing the voltages across each material, i.e. across each layer of the test object. These equations have been solved considering a DC step voltage across the whole test object. Based on this, the time-dependent electric field in each material as well as the time-dependent polarization current density in the test object have been calculated. The calculated polarization current density was found to agree well with the measured polarization current density of the test object. This indicates that application of dielectric response theory gives a good estimate of the time-dependent electric field distribution in layered insulation systems. The results show that 90 % of the change from initial values to steady-state values for the electric fields has occurred within the first 35 minutes after the voltage step. This applies to the electric fields in both of the materials of the examined test object at a temperature of 323 K.
Practical Notes on the Measurement and Interpretation of Thermally Stimulated Discharge Currents in Biaxially Oriented Polypropylene
Authors: Rytöluoto Ilkka , Niittymäki Minna , Lahti Kari
Published: August 2019

The measurement and interpretation of high-field thermally stimulated depolarization current (TSDC) of capacitor-grade biaxially oriented polypropylene (BOPP) films are investigated in order to facilitate the derivation of trap parameters. Two main relaxations associable with the glass transition and detrapping of space charge from deep traps are observed, and their dependence on the polarization/depolarization conditions are studied. The complex bipolar nature of the space charge relaxation makes the derivation of trap parameters challenging. Lastly, a brief attempt is made to correlate the TSDC features with morphology and other short-term dielectric properties.
Surface Hydrophobicity in Medium Voltage Terminations
Authors: Väkeväinen Kenneth Kimmo Miika
Published: August 2019

The surface hydrophobicity in medium voltage terminations is studied in this paper to see if the performance of aged heat shrink terminations could be improved. Terminations which are used inside of unheated outdoor enclosures can often be subjected to leakage currents and surface discharges along the insulating surface if the environmental conditions inside the enclosure become harsh. The discharge phenomena on the insulating surface is generally not critical but continuous electrical activity on the surface could eventually lead to a flashover or breakdown as the materials age. The effect of surface hydrophobicity was studied by comparing the performance of heat shrink terminations over a longer time in operation. Improvements were done to aged heat shrink indoor terminations which already had signs of discharge occurrence on the termination surfaces. The results indicate that the performance of these aged terminations improved simply by increasing the surface hydrophobicity of the original installation. The improvement can be done by applying a silicone coating on the termination surface. This solution offers a convenient method for improving the performance of aged heat shrink terminations used in unheated outdoor enclosures.
Solution Modified Fumed Silica and Its Effect on Charge Trapping Behavior of PP/POE/Silica Nanodielectrics
Authors: Mathabani Amirhossein , Rytöluoto Ilkka , He Xiaozhen , Saarimäki Eetta , Lahti Kari , Paajanen Mika , Anyszka Rafal , Dierkes Wilma , Blume Anke
Published: August 2019

Various dielectric nanocomposite materials are studied in the frame of the European Commission funded project GRIDABLE. This project has the aim to develop DC cable extruded insulation and medium and low voltage DC capacitor films exhibiting enhanced performance with respect to presently used materials. The nanocomposites intended for cable applications are polypropylene (PP)/polyolefin elastomer (POE) blends filled with surface modified nano-silica particles. The surface modification is carried out via the state-of-the-art solution method using a polar silane as the modifying agent. Thermally Stimulated Depolarization Current (TSDC) measurements were carried out in order to study the charge trapping behavior of the nanocomposite samples. TSDC results indicate that the addition of the treated nano-silica, for most cases, reduces the density of the deep traps significantly. The effect of the addition of silica nanoparticles - both modified and unmodified - on the crystallinity of the samples was studied using X-ray Diffraction (XRD). This is important as the charge trapping properties of the nanodielectrics can be affected by the degree of crystallinity. While more detailed studies are necessary, these results imply that the depth and the density of the deep trap states is profoundly influenced by the level of the silica modification i.e. the amount of the grafted silane on the silica surface.
Fashioning Fame: Fernando de Herrera'sAnotacionesas a Space of Knowledge
Authors: Lazure Guy
Published: August 2019

The 1580 edition of Fernando de Herrera's Anotaciones a Garcilaso marked the entrance of a new protagonist in the literary landscape of Golden Age poetry. Contrasting the notions of “academies” and “spaces of knowledge”, this article focuses on how Herrera and the group of Sevillian literati who collaborated on the project took advantage of this publication to make a name for themselves within the Spanish republic of letters. Their efforts are examined through the different strategies for authority elaborated in the book's paratextual material, as well as the various critical responses and reactions to the Anotaciones.
Rebolledo, un poeta ante la imprentaRebolledo, a Poet at the Printing Press
Authors: Pérez Pedro Ruiz
Published: August 2019

Aristocrat and diplomat Bernardino de Rebolledo regularly resorted to the printing press to disseminate his verses and materially shape them in books. More idiosyncratically, indeed a novelty in Spain at the time, he also reviewed the process that lead to the publication of his complete works. As an amateur writer, his use of the printing press and his entering the book market were remarkably free of economic reasons. The publication of Rebolledo's works illustrates the distance between the oral, courtly practice of poetry and its materialization in a book, a process that stands both as an obstacle and a springboard in the development of authorial conscience and of the idea of poet.
Recruiting the underrepresented to academic libraries
Authors: Recruitment of Underrepresented Minorities ACRL Task Force on
Published: August 2019

Recruiting the underrepresented to academic libraries
Functional group based marine ecosystem assessment for the Bay of Biscay via elasticity analysis
Authors: Hosack Geoffrey R. , Trenkel Verena M.
Published: August 2019

The transitory and long-term elasticities of the Bay of Biscay ecosystem to density-independent and density-dependent influences were estimated within a state space model that accounted for both process and observation uncertainties. A functional group based model for the Bay of Biscay fish ecosystem was fit to time series obtained from scientific survey and commercial catch and effort data. The observation model parameters correspond to the unknown catchabilities and observation error variances that vary across the commercial fisheries and fishery-independent scientific surveys. The process model used a Gompertz form of density dependence, which is commonly used for the analysis of multivariate ecological time series, with unknown time-varying fishing mortalities. Elasticity analysis showed that the process model parameters are directly interpretable in terms of one-year look-ahead prediction elasticities, which measure the proportional response of a functional group in the next year given a proportional change to a variable or parameter in the current year. The density dependent parameters were also shown to define the elasticities of the long term means or quantiles of the functional groups to changes in fishing pressure. Evidence for the importance of indirect effects, mediated by density dependence, in determining the ecosystem response of the Bay of Biscay to changes in fishing pressure is presented. The state space model performed favourably in an assessment of model adequacy that compared observations of catch per unit effort against cross-validation predictive densities blocked by year.
Effect of Hexanal as a Post-harvest Treatment to Extend the Shelf-life of Banana Fruits (Musa acuminata var. Sweet Banana) in Kenya
Authors: Yumbya Peninah , Hutchinson Margaret , Ambuko Jane , Owino Willis
Published: August 2019

The short shelf-life of fruits in the tropics continues to be a pressing problem for farmers and other value chain actors. Hexanal is a naturally occurring compound that has received attention as a novel postharvest compound preservative. This study was conducted to determine the effect of hexanal on enhancing the postharvest shelf-life and quality of ‘sweet banana’ fruits. Two hexanal concentrations (2% and 3%) were applied as either a pre-harvest spray or a post-harvest dip. Fruits were obtained from two different agro ecological zones of Kenya (AEZs II and IV). The treated fruits were kept under ambient room conditions of 25 ± 1°C and RH 60 ± 5% to ripen. Hexanal treatment maintained the fruits quality and prolonged the shelf-life by 6 days in the dipped fruits, 6 and 3 days in the sprayed fruits from the drier AEZ IV and colder AEZ II respectively compared to the untreated controls. Hexanal treatments significantly (P = .05) delayed or reduced the rate of most of the physicochemical parameters analysed irrespective of the concentration and mode of application used. Fruit firmness was significantly (P = .05) maintained up to day 6 and 9 of storage in the treated fruits compared to the controls which softened drastically as from day 3 and 6 in the sprayed and dipped fruits respectively. Hexanal treatment delayed ethylene and respiratory peaks by 3 days in both modes of application and significantly delayed progression of other ripening related changes such as 0Brix, titratable acidity, simple sugars and vitamin C. Sensory evaluation showed no significant differences in the various quality attributes analysed between the hexanal treated and control fruits. The results of this study indicate that, use of hexanal is a potential technology that could be adopted by banana farmers to enhance post-harvest shelf-life without compromising on quality.
Effects of the Administration of Thyroid Hormones in Cases of Hepatic Ischemia and Reperfusion Injury
Authors: Ustun Yasemin Burcu , Kaya Cengiz , Koksal Ersin , Atalay Yunus , Yilmaz Ziya , Torun Aysun Caglar , Karabicak Ilhan , Aksoy Abdurrahman , Yarim Murat
Published: August 2019

Objective:

Hepatic ischemia and reperfusion (IR) injury is the most important cause of cellular death and hepatic dysfunction following liver transplantation and resection. Our aim in this study is to reveal the early stage effects of thyroid hormone levels on hepatic IR injury that effectively act on cellular homeostasis.

Methods:

Forty-six male Wistar albino rats were divided into 6 groups as follows: euthyroid-sham (n = 8), euthyroid with IR injury (n = 8), hyperthyroid-sham (n = 7), hyperthyroid with IR injury (n = 7), hypothyroid-sham (n = 8), and hypothyroid with IR injury (n = 8). After 90 minutes of partial hepatic ischemia, 90 minutes of reperfusion was applied. Liver tissue malondialdehyde (MDA) levels, catalase (CAT), glutathion peroxidase, and superoxide dismutase (SOD) enzyme activities were measured. Hepatic tissue was immunohistochemically analyzed.

Results:

MDA levels of liver tissue were analyzed, and hepatic MDA levels in the hyper-IR group were found to be significantly lower (P = 0.002) than those of the hypo-IR and euthyroid-IR groups. Serum CAT levels did not differ between control groups, whereas CAT values in the hyper-IR group were detected to be significantly lower than in the euthyroid-IR and hypothyroid-IR groups (P = 0.003). However, levels of SOD and glutathione peroxidase (GPX) were not affected by the functional state of the thyroid. No statistically significant difference was seen in the results of the histopathologic evaluation and immunohistochemical staining of the liver tissue.

Conclusion:

The administration of thyroid hormone within a short time before IR injury may have protective effects.
Noise reduction in dual‐energy computed tomography virtual monoenergetic imaging
Authors: Liu Chi‐Kuang , Huang Hsuan‐Ming
Published: August 2019

Purpose

Virtual monoenergetic images (VMIs) derived from dual‐energy computed tomography (DECT) have been explored for several clinical applications in recent years. However, VMIs at low and high keVs have high levels of noise. The aim of this study was to reduce image noise in VMIs by using a two‐step noise reduction technique.

Methods

VMI was first denoised using a modified highly constrained backprojection (HYPR) method. After the first‐step denoising, a general‐threshold filtering method was performed. Two sets of anthropomorphic phantoms were scanned with a clinical dual‐source DECT system. DECT data (80/140Sn kV) were reconstructed as VMI series at 12 different energy levels (range, 40‐150 keV, interval, 10 keV). For comparison, the averaged VMIs obtained from 10 repeated DECT scans were used as the reference standard. The signal‐to‐noise ratio (SNR), contrast‐to‐noise ratio (CNR) and root‐mean‐square error (RMSE) were used to evaluate the quality of VMIs.

Results

Compared to the original HYPR method, the proposed two‐step image denoising method could provide better performance in terms of SNR, CNR, and RMSE. In addition, the proposed method could achieve effective noise reduction while preserving edges and small structures, especially for low‐keV VMIs.

Conclusion

The proposed two‐step image denoising method is a feasible method for reducing noise in VMIs obtained from a clinical DECT scanner. The proposed method can also reduce edge blurring and the loss of intensity in small lesions.
Lubrication Characteristics of Epoxy Resin‐Based Monolithic Thin Films with a Well‐Defined Porous Morphology
Authors: Shimizu Yoshihiko , Sakakibara Keita , Yasuda Syuma , Tsujii Yoshinobu
Published: August 2019

The tribological properties of epoxy resin‐based monolithic materials filled with lubricants are described. They exhibit viscoelastic compression behavior, with films of smaller thickness or smaller pore size exhibiting higher stiffness. The frictional coefficient is scaled by the thickness and pore size, indicating the unique properties of novel soft and resilient porous polymer/lubricant systems.
Two‐Phase Emulgels for Direct Ink Writing of Skin‐Bearing Architectures
Authors: Huan Siqi , Mattos Bruno D. , Ajdary Rubina , Xiang Wenchao , Bai Long , Rojas Orlando J.
Published: August 2019

Direct ink writing (DIW) provides programmable and customizable platforms to engineer hierarchically organized constructs. However, one‐step, facile synthesis of such architectures via DIW has been challenging. This study introduces inks based on two‐phase emulgels for direct printing and in situ formation of protecting layers enveloping multicomponent cores, mimicking skin‐bearing biological systems. The emulgel consists of a Pickering emulsion with an organic, internal phase containing poly(lactic acid) stabilized by chitin/cellulose nanofibers and a continuous, cross‐linkable hydrogel containing cellulose nanofibers and any of the given solid particles. The shear during ink extrusion through nozzles of low surface energy facilitates the generation of the enveloped structures via fast and spontaneous phase separation of the emulgel. The skin‐bearing architectures enable control of mass transport as a novel configuration for cargo release. As a demonstration, a hydrophilic molecule is loaded in the hydrogel, which is released through the core and skin, enabling regulation of diffusion and permeation phenomena. This 3D‐printed functional material allows independent control of strength owing to the hierarchical construction. The new method of fabrication is proposed as a simple way to achieve protection, regulation, and sensation, taking the example of the functions of skins and cuticles, which are ubiquitous in nature.
An Optically Responsive Soft Etalon Based on Ultrathin Cellulose Hydrogels
Authors: Dong Yue , Akinoglu Eser Metin , Zhang Heyou , Maasoumi Fatemeh , Zhou Jinping , Mulvaney Paul
Published: August 2019

Stimuli‐responsive optical etalons are an exciting class of next‐generation sensors because they are scalable, cost‐effective and offer tunability of their optical response across the entire UV–vis–NIR wavelength range. In this study, double‐network cellulose hydrogels are used as a soft, responsive medium and are incorporated into Fabry–Pérot optical etalons. The thin cellulose hydrogel layer can be solution processed. The hygroscopic hydrogel undergoes both refractive index and thickness changes in response to changes in humidity. This leads to strong changes in reflection due to optical interference within the metal–insulator–metal (MIM) cavity. The response can be optimized by adjusting the chemical crosslinker ratio. These flexible MIM structures provide a robust platform for optically based chemical sensors.
Fluorous Metal–Organic Frameworks and Nonporous Coordination Polymers as Low‐κ Dielectrics
Authors: Galli Simona , Cimino Alessandro , Ivy Joshua F. , Giacobbe Carlotta , Arvapally Ravi K. , Vismara Rebecca , Checchia Stefano , Rawshdeh Mustafa A. , Cardenas Christian T. , Yaseen Waleed K. , Maspero Angelo , Omary Mohammad A.
Published: August 2019

A fluorous metal–organic framework [Cu(FBTB)(DMF)] (FMOF‐3) [H2FBTB = 1,4‐bis(1‐H‐tetrazol‐5‐yl)tetrafluorobenzene] and fluorous nonporous coordination polymer [Ag2(FBTB)] (FN‐PCP‐1) are synthesized and characterized as for their structural, thermal, and textural properties. Together with the corresponding nonfluorinated analogues lc‐[Cu(BTB)(DMF)] and [Ag2(BTB)], and two known (super)hydrophobic MOFs, FMOF‐1 and ZIF‐8, they have been investigated as low‐dielectric constant (low‐κ) materials under dry and humid conditions. The results show that substitution of hydrogen with fluorine or fluoroalkyl groups on the organic linker imparts higher hydrophobicity and lower polarizability to the overall material. Pellets of FMOF‐1, FMOF‐3, and FN‐PCP‐1 exhibit κ values of 1.63(1), 2.44(3), and 2.57(3) at 2 × 106 Hz, respectively, under ambient conditions, versus 2.94(8) and 3.79(1) for lc‐[Cu(BTB)(DMF)] and [Ag2(BTB)], respectively. Such low‐κ values persist even upon exposure to almost saturated humidity levels. Correcting for the experimental pellet density, the intrinsic κ for FMOF‐1 reaches the remarkably low value of 1.28, the lowest value known to date for a hydrophobic material.
Molecular Beam Epitaxy and Electronic Structure of Atomically Thin Oxyselenide Films
Authors: Liang Yan , Chen Yujie , Sun Yuanwei , Xu Shipu , Wu Jinxiong , Tan Congwei , Xu Xiaofeng , Yuan Hongtao , Yang Lexian , Chen Yulin , Gao Peng , Guo Jiandong , Peng Hailin
Published: August 2019

Atomically thin oxychalcogenides have been attracting intensive attention for their fascinating fundamental properties and application prospects. Bi2O2Se, a representative of layered oxychalcogenides, has emerged as an air‐stable high‐mobility 2D semiconductor that holds great promise for next‐generation electronics. The preparation and device fabrication of high‐quality Bi2O2Se crystals down to a few atomic layers remains a great challenge at present. Here, molecular beam epitaxy (MBE) of atomically thin Bi2O2Se films down to monolayer on SrTiO3 (001) substrate is achieved by co‐evaporating Bi and Se precursors in oxygen atmosphere. The interfacial atomic arrangements of MBE‐grown Bi2O2Se/SrTiO3 are unambiguously revealed, showing an atomically sharp interface and atom‐to‐atom alignment. Importantly, the electronic band structures of one‐unit‐cell (1‐UC) thick Bi2O2Se films are observed by angle‐resolved photoemission spectroscopy (ARPES), showing low effective mass of ≈0.15 m0 and bandgap of ≈0.8 eV. These results may be constructive to the synthesis of other 2D oxychalcogenides and investigation of novel physical properties.
Biofunctionalization of Glass‐ and Paper‐Based Microfluidic Devices: A Review
Authors: Shakeri Amid , Jarad Noor Abu , Leung Ashlyn , Soleymani Leyla , Didar Tohid F.
Published: August 2019

Biofunctionalization of microchannels is of great concern in the fabrication of microfluidic devices. Different substrates such as glass slides, papers, polymers, and beads require different biofunctionalization approaches granting the utilization of microfluidics in several biomedical applications. Covalent immobilization of biomolecules inside the microchannels is achieved by chemical modification of the surface such as silanization or introducing different coupling agents. Although creating biointerfaces that are covalently bonded to the microchannel surface necessitates multiple steps of surface modification and incubation times, it bestows a robust biointerface capable of withstanding high shear stresses and harsh conditions without dissipating the biofunctionality. Regarding the applications that do not require robustness and long‐term stability, noncovalent attachment of biomolecules such as van der Waals and hydrophobic interactions are adequate to successfully create a functional biointerface. This review summarizes the various biofunctionalization approaches used in the most common microfluidic substrates: glass and paper. In addition, several biofunctionalization examples are proposed and described in detail along with their associated applications.
Enhancing Photocatalytic Activity of NO Removal through an In Situ Control of Oxygen Vacancies in Growth of TiO2
Authors: Shen Xiaoling , Dong Guohui , Wang Lan , Ye Liqun , Sun Jianwu
Published: August 2019

Although defects play an important role in the photocatalytic activity of TiO2, the mechanism of the photocatalytic activity related to different defects remains disputable. Moreover, the reported methods to introduce defects raise the preparation cost. In this work, different types of defects including O‐vacancy cluster, surface O‐vacancy, and bulk O‐vacancy defects are in situ introduced in TiO2 by controlling the crystallization temperature. The medium‐degree crystallinity TiO2 sample mainly containing surface O‐vacancies exhibits the best NO removal activity. The systematic study of photocatalytic mechanism demonstrates that the surface O‐vacancies significantly promote the adsorption of H2O molecules and improve charge transfer to the adsorbed H2O forming ·OH, thus dramatically enhancing the photocatalytic NO removal activity. On the contrary, bulk O‐vacancies neither help the adsorption of H2O molecules, nor improve the charge transfer to H2O.
Visible Colorimetric Oxygen Indicator Based on Ag‐Loaded TiO2 Nanotubes for Quick Response and Real‐Time Monitoring of the Integrity of Modified Atmosphere Packaging
Authors: Wen Junwei , Huang Shuting , Jia Ling , Ding Fuyuan , Li Houbin , Chen Lingyun , Liu Xinghai
Published: August 2019

Oxygen indication is a new technique for non‐destructive testing (NDT) of modified atmosphere packaging (MAP). Damage may occur at any time during the transportation and storage of MAP, resulting in increased oxygen concentration. This may lead to food quality decline and even food spoilage. However, it is difficult to judge whether the package is undamaged without professional equipment. A visible colorimetric oxygen indicator that can accurately identify an intact packaging system to ensure food safety is reported. The indicator consists of an Ag‐loaded titanium dioxide nanotube (Ag‐TNT), glycerol, methylene blue (MB), and hydroxyethyl cellulose (HEC). According to X‐ray diffraction, X‐ray photoelectron spectroscopy, transmission electron microscopy, Brunauer–Emmett–Teller analysis, diffuse reflectance spectroscopy, and UV–vis results, the Ag‐TNT showed efficient photocatalytic performance, increased specific surface area (from 85 to 227 m2 g−1), and an increased band gap of 3.30 eV. These results dramatically improved the performance of Ag‐TNT as an oxygen indicator. Additionally, it demonstrated two outstanding properties: blocking indicator response to natural light (wavelength > 380 nm) and shortening the bleaching time during activation. Such an oxygen indicator can considerably enhance the accuracy of NDT for packages. Furthermore, it can be used in the packaging of different foodstuffs, ensuring food safety.
Semiconductor Quantum Dots‐Embedded Inorganic Glasses: Fabrication, Luminescent Properties, and Potential Applications
Authors: Xia Mengling , Luo Jiajun , Chen Chao , Liu Huan , Tang Jiang
Published: August 2019

Quantum dots (QDs)‐embedded inorganic glasses combine the outstanding luminescent properties of QDs with the chemical, mechanical, and thermal stability of glasses, overcoming the instability bottleneck of QDs and facilitating their wide and endurable applications such as nonlinear optical devices, light emission, and signal amplification in the fiber‐optic communication system. Typical QDs incorporated into glasses include IIB‐VIA (e.g., ZnO, CdSe), IVB‐VIA (e.g., PbS), and halide perovskite (CsPbBr3, et al.) QDs. Here, the preparation methods and growth kinetics of QDs in glasses are first discussed, followed by the summary of the optical properties and application explorations of IIB‐VIA, IVB‐VIA, and halide perovskite QDs‐embedded glasses. Finally, research directions to overcome the major challenges associated with these glasses for ultimate applications are proposed.
Light‐Stimulated Charge Transport in Bilayer Molecular Junctions for Photodetection
Authors: Saxena Shailendra K. , Smith Scott R. , Supur Mustafa , McCreery Richard L.
Published: August 2019

Eleven bilayer molecular junctions (MJs) consisting of two different 5–7 nm thick molecular layers between conducting contacts are investigated to determine how orbital energies and optical absorbance spectra of the oligomers affect the photocurrent (PC) response, the direction of photoinduced charge transport, and maximum response wavelength. Photometric sensitivity of 2 mA W−1 and a detection limit of 11 pW are demonstrated for MJs, yielding an internal quantum efficiency of 0.14 electrons per absorbed photon. For unbiased MJs, the PC tracks the absorption spectrum of the molecular layer, and is stable for >5 h of illumination. The organic/organic (O/O) interface between the molecular layers within bilayer MJs is the primary determinant of PC polarity, and the bilayer MJ mechanism is conceptually similar to that of a single O/O heterojunction studied in bilayers of much greater thickness. The charge transport direction of the 11 MJs is completely consistent with hole‐dominated transport of photogenerated carriers. For MJs illuminated while an external bias is applied, the PC greatly exceeds the dark current by factors of 102 to 105, depending on bias, bilayer structure, and wavelength. The bilayer MJs are amenable to flexible substrates, and may have applications as sensitive, wavelength‐specific photodetectors.
Influence of Grain Size on Phase Transitions in Halide Perovskite Films
Authors: Stavrakas Camille , Zelewski Szymon J. , Frohna Kyle , Booker Edward P. , Galkowski Krzysztof , Ji Kangyu , Ruggeri Edoardo , Mackowski Sebastian , Kudrawiec Robert , Plochocka Paulina , Stranks Samuel D.
Published: August 2019

Grain size in polycrystalline halide perovskite films is known to have an impact on the optoelectronic properties of the films, but its influence on their soft structural properties and phase transitions is unclear. Here, temperature‐dependent X‐ray diffraction, absorption, and macro‐ and micro‐photoluminescence measurements are used to investigate the tetragonal to orthorhombic phase transition in thin methylammonium lead iodide films with grain sizes ranging from the micrometer scale down to the tens of nanometer scale. It is shown that the phase transition nominally at ≈150 K is increasingly suppressed with decreasing grain size and, in the smallest grains, the first evidence of a phase transition is only seen at temperatures as low as ≈80 K. With decreasing grain size, an increasing magnitude of the hysteresis is also seen in the structural and optoelectronic properties when cooling to, and then upon heating from, 100 K. This work reveals the remarkable sensitivity of the optoelectronic, physical, and phase properties to the local environment of the perovskite structure, which will have large ramifications for phase and defect engineering in operating devices.
Resistive Memory‐Based In‐Memory Computing: From Device and Large‐Scale Integration System Perspectives
Authors: Yan Bonan , Li Bing , Qiao Ximing , Xue Cheng-Xin , Chang Meng‐Fan , Chen Yiran , Li Hai (Helen)
Published: August 2019

In‐memory computing is a computing scheme that integrates data storage and arithmetic computation functions. Resistive random access memory (RRAM) arrays with innovative peripheral circuitry provide the capability of performing vector‐matrix multiplication beyond the basic Boolean logic. With such a memory–computation duality, RRAM‐based in‐memory computing enables an efficient hardware solution for matrix‐multiplication‐dependent neural networks and related applications. Herein, the recent development of RRAM nanoscale devices and the parallel progress on circuit and microarchitecture layers are discussed. Well suited for analog synapse and neuron implementation, RRAM device properties and characteristics are emphasized herein. 3D‐stackable RRAM and on‐chip training are introduced in large‐scale integration. The circuit design and system organization of RRAM‐based in‐memory computing are essential to breaking the von Neumann bottleneck. These outcomes illuminate the way for the large‐scale implementation of ultra‐low‐power and dense neural network accelerators.
Damage to leaf veins suppresses root foraging precision
Authors: Yamawo Akira , Ohsaki Haruna , Cahill James F.
Published: August 2019

Premise

Plants generally increase root growth in areas with high nutrients in heterogeneous soils, a phenomenon called foraging precision. The physiology of this process is not well understood, but it may involve shoot–root signaling via leaf veins. If this is true, then damage to leaf veins, but not to nearby mesophyll, would reduce plant foraging precision.

Methods

To test this hypothesis, we imposed two leaf damage treatments on Plantago asiatica and Prunus jamasakura, removing either the tip of each main vein or mesophyll tissue between the veins with a 3‐mm‐diameter hole punch. After 30 days or 20 weeks of plant growth, we measured root biomass in the soil in response to soil nutrient concentration.

Results

When leaf mesophyll was damaged, root biomass of both species was greater in nutrient‐rich patches than in nutrient‐poor patches. However, when leaf veins were damaged, root biomass was similar between patches.

Conclusions

These results suggest the importance of shoot–root signaling in plants, emphasizing that physiological processes are not necessarily restricted to single organs. The idea that herbivores that damage leaf veins may affect a plant's ability to selectively forage in high‐nutrient patches is novel, with implications for natural and managed systems.
The association between knee breadth and body mass: The Northern Finland Birth Cohort 1966 case study
Authors: Keisu Asla , Oura Petteri , Niskanen Markku , Ruff Christopher B. , Niinimäki Jaakko , Arvola Timo , Auvinen Juha , Tuukkanen Juha , Lehenkari Petri , Junno Juho‐Antti
Published: August 2019

Objectives

Body mass estimation from skeletal dimensions is a useful tool when studying archeological human samples. Bony articular surface dimensions of the lower limb have frequently been utilized to estimate body size. In the present study, we investigated the association between knee breadth and body mass in a Northern European population. Our study aimed to confirm both methodology and results presented in earlier studies.

Materials and methods

The study sample consists of 1,290 subjects belonging to the Northern Finland Birth Cohort 1966. Three knee breadth dimensions—femoral biepicondylar breadth, mediolateral breadth of femoral condyles, and mediolateral breadth of the tibial plateau—were measured from subjects' knee PA‐radiographs. Measurements and their association with body weight at 31 years were utilized for creating body mass estimation equations using linear regression and reduced major axis regression. Correlations between knee measurements and body weight at three different ages (18, 31, and 46) were also analyzed.

Results

Positive associations were detected between each knee breadth variable and weight in the total sample and both genders separately. Body mass estimation equations were created for the total sample, for males and for females. R values of the models ranged from 0.38 to 0.74. Median absolute percent prediction errors ranged from 6.89 to 9.72%. The highest correlations were obtained between knee breadth and body weight in early adulthood.

Discussion

Our large sample confirmed that equations derived from knee breadth dimensions are accurate when estimating body mass of modern humans. Knee breadth measurements clearly have a positive association with body weight in early maturity.
Synthesis of Sulfonimidamides from Sulfenamides via an Alkoxy‐amino‐λ6‐sulfanenitrile Intermediate
Authors: Briggs Edward L. , Tota Arianna , Colella Marco , Degennaro Leonardo , Luisi Renzo , Bull James A.
Published: August 2019

Sulfonimidamides are intriguing new motifs for medicinal and agrochemistry, and provide attractive bioisosteres for sulfonamides. However, there remain few operationally simple methods for their preparation. Here, the synthesis of NH‐sulfonimidamides is achieved directly from sulfenamides, themselves readily formed in one step from amines and disulfides. A highly chemoselective and one‐pot NH and O transfer is developed, mediated by PhIO in iPrOH, using ammonium carbamate as the NH source, and in the presence of 1 equivalent of acetic acid. A wide range of functional groups are tolerated under the developed reaction conditions, which also enables the functionalization of the antidepressants desipramine and fluoxetine and the preparation of an aza analogue of the drug probenecid. The reaction is shown to proceed via different and concurrent mechanistic pathways, including the formation of novel S≡N sulfanenitrile species as intermediates. Several alkoxy‐amino‐λ6‐sulfanenitriles are prepared with different alcohols, and shown to be alkylating agents to a range of nucleophiles.
An Oligothiophene–Fullerene Molecule with a Balanced Donor–Acceptor Backbone for High‐Performance Single‐Component Organic Solar Cells
Authors: Wang Wei , Sun Rui , Guo Jing , Guo Jie , Min Jie
Published: August 2019

A new balanced donor–acceptor molecule, namely, benzodithiophene (BDT)‐rhodanine‐[6,6]‐phenyl‐C71 butyric acid methyl ester (Rh‐PC71BM) comprising two covalently linked blocks, a p‐type oligothiophene‐containing BDT‐based moiety and an n‐type PC71BM unit was designed and synthesized. The single‐component organic solar cell (SCOSC) fabricated from Rh‐PC71BM molecules showed a power conversion efficiency (PCE) of 3.22 % with an open‐circuit voltage (Voc) of 0.98 V. These results rank are among the highest values for SCOSCs based on a monomolecular material. In particular, the one‐molecule Rh‐PC71BM device exhibits excellent thermal stability compared to reference Rh‐OH:PC71BM device. The success of our monomolecular strategy can provide a new way to develop high‐performance SCOSCs.
A Nanobody‐Conjugated DNA Nanoplatform for Targeted Platinum‐Drug Delivery
Authors: Wu Tiantian , Liu Jianbing , Liu Manman , Liu Shaoli , Zhao Shuai , Tian Run , Wei Dengshuai , Liu Yangzhong , Zhao Yao , Xiao Haihua , Ding Baoquan
Published: August 2019

The targeted delivery of chemotherapeutic drugs is a major challenge in the clinical treatment of cancer. Herein, we constructed a multifunctional DNA nanoplatform as a versatile carrier of the highly potent platinum‐based DNA intercalator, 56MESS. In our rational design, 56MESS was efficiently loaded into the double‐bundle DNA tetrahedron through intercalation with the DNA duplex. With the integration of a nanobody that both targets and blocks epidermal growth factor receptor (EGFR), the DNA nanocarriers exhibit excellent selectivity for cells with elevated EGFR expression (a common biomarker related to tumor formation) and combined tumor therapy without obvious systemic toxicity. This DNA‐based platinum‐drug delivery system provides a promising strategy for the treatment of tumors.
A Nickel‐Diamine/Mesoporous Silica Composite as a Heterogeneous Chiral Catalyst for Asymmetric 1,4‐Addition Reactions
Authors: Ishitani Haruro , Kanai Kan , Yoo Woo‐Jin , Yoshida Tomoko , Kobayashi Shū
Published: August 2019

A chiral composite material, derived from the deposition of a chiral nickel–diamine complex via wet impregnation to MCM‐41, was shown to be an efficient heterogeneous catalyst for asymmetric 1,4‐addition reactions of 1,3‐dicarbonyl compounds with nitroalkenes, and of nitromethane with alkylidenemalonates. It was discovered that MCM‐41 enhanced the reactivity and improved the stability of the chiral nickel complex that resides within the mesoporous material.
In Situ Single‐Cell Western Blot on Adherent Cell Culture
Authors: Zhang Yizhe , Naguro Isao , Herr Amy E.
Published: August 2019

Integrating 2D culture of adherent mammalian cells with single‐cell western blotting (in situ scWB) uses microfluidic design to eliminate the requirement for trypsin release of cells to suspension, prior to single‐cell isolation and protein analysis. To assay HeLa cells from an attached starting state, we culture adherent cells in fibronectin‐functionalized microwells formed in a thin layer of polyacrylamide gel. To integrate the culture, lysis, and assay workflow, we introduce a one‐step copolymerization process that creates protein‐decorated microwells. After single‐cell culture, we lyse each cell in the microwell and perform western blotting on each resultant lysate. We observe cell spreading after overnight microwell‐based culture. scWB reports increased phosphorylation of MAP kinases (ERK1/2, p38) under hypertonic conditions. We validate the in situ scWB with slab‐gel western blot, while revealing cell‐to‐cell heterogeneity in stress responses.
Facile Stereoselective Approach to Diverse Spiroheterocyclic Tetrahydropyrans: Concise Synthesis of (+)‐Broussonetine G and H
Authors: Zhou Li , Yu Shu‐Yang , Tang Yong , Wang Lijia
Published: August 2019

A highly diastereoselective copper‐catalyzed multicomponent cyclization of exocyclic enol ethers/enamines with methylene malonate and aldehydes has been developed to furnish spiroheterocyclic tetrahydropyrans in high yields with greater than 95:5 d.r. This method is practical, in that 36 examples, including a range of aldehydes and exo‐vinyl heterocycles, are presented. By applying the newly developed method, the total synthesis of (+)‐broussonetine G and formal synthesis of (+)‐broussonetine H were achieved in a concise way.