bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of Variations in the Extraction Yield, Phenolic Contents and Antioxidant Activities of the Bark of F. religiosa as a Function of Extraction Procedure
Authors: Aftab Ashraf  , Ijaz Ahmad Bhatti  , Bushra Sultana  , Amer Jamil
Published: January 2016

In present study, the effect of different solvents and multiple techniques on the extraction yield, phenolic contents and antioxidant activities of bark of F. Religiosa, was investigated. Four solvents (absolute ethanol, absolute methanol, 80% aqueous ethanol and 80% aqueous methanol) and three techniques (orbital shaker, sonication and magnetic stirrer) were applied for this purpose. The extract obtained by the application of 80% methanol, exhibited significantly (p 80% ethanol > absolute methanol >absolute ethanol. As for as techniques are concerned, the extracts obtained by the application of sonication demonstrated significantly (p
The magnesium transporter A is activated by cardiolipin and is highly sensitive to free magnesium in vitro
Authors: Subramani Saranya , Perdreau-Dahl Harmonie , Morth Jens Preben
Published: January 2016

The magnesium transporter A (MgtA) is a specialized P-type ATPase, believed to import Mg2+ into the cytoplasm. In Salmonella typhimurium and Escherichia coli, the virulence determining two-component system PhoQ/PhoP regulates the transcription of mgtA gene by sensing Mg2+ concentrations in the periplasm. However, the factors that affect MgtA function are not known. This study demonstrates, for the first time, that MgtA is highly dependent on anionic phospholipids and in particular, cardiolipin. Colocalization studies confirm that MgtA is found in the cardiolipin lipid domains in the membrane. The head group of cardiolipin plays major role in activation of MgtA suggesting that cardiolipin may act as a Mg2+ chaperone for MgtA. We further show that MgtA is highly sensitive to free Mg2+ (Mg2+free) levels in the solution. MgtA is activated when the Mg2+free concentration is reduced below 10 μM and is strongly inhibited above 1 mM, indicating that Mg2+free acts as product inhibitor. Combined, our findings conclude that MgtA may act as a sensor as well as a transporter of Mg2+.
Rho-associated kinase (ROCK) function is essential for cell cycle progression, senescence and tumorigenesis
Authors: Kümper Sandra , Mardakheh Faraz K , McCarthy Afshan , Yeo Maggie , Stamp Gordon W , Paul Angela , Worboys Jonathan , Sadok Amine , Jørgensen Claus , Guichard Sabrina , Marshall Christopher J
Published: January 2016

Rho-associated kinases 1 and 2 (ROCK1/2) are Rho-GTPase effectors that control key aspects of the actin cytoskeleton, but their role in proliferation and cancer initiation or progression is not known. Here, we provide evidence that ROCK1 and ROCK2 act redundantly to maintain actomyosin contractility and cell proliferation and that their loss leads to cell-cycle arrest and cellular senescence. This phenotype arises from down-regulation of the essential cell-cycle proteins CyclinA, CKS1 and CDK1. Accordingly, while the loss of either Rock1 or Rock2 had no negative impact on tumorigenesis in mouse models of non-small cell lung cancer and melanoma, loss of both blocked tumor formation, as no tumors arise in which both Rock1 and Rock2 have been genetically deleted. Our results reveal an indispensable role for ROCK, yet redundant role for isoforms 1 and 2, in cell cycle progression and tumorigenesis, possibly through the maintenance of cellular contractility.
A chemical proteomic atlas of brain serine hydrolases identifies cell type-specific pathways regulating neuroinflammation
Authors: Viader Andreu , Ogasawara Daisuke , Joslyn Christopher M , Sanchez-Alavez Manuel , Mori Simone , Nguyen William , Conti Bruno , Cravatt Benjamin F
Published: January 2016

Metabolic specialization among major brain cell types is central to nervous system function and determined in large part by the cellular distribution of enzymes. Serine hydrolases are a diverse enzyme class that plays fundamental roles in CNS metabolism and signaling. Here, we perform an activity-based proteomic analysis of primary mouse neurons, astrocytes, and microglia to furnish a global portrait of the cellular anatomy of serine hydrolases in the brain. We uncover compelling evidence for the cellular compartmentalization of key chemical transmission pathways, including the functional segregation of endocannabinoid (eCB) biosynthetic enzymes diacylglycerol lipase-alpha (DAGLα) and –beta (DAGLβ) to neurons and microglia, respectively. Disruption of DAGLβ perturbed eCB-eicosanoid crosstalk specifically in microglia and suppressed neuroinflammatory events in vivo independently of broader effects on eCB content. Mapping the cellular distribution of metabolic enzymes thus identifies pathways for regulating specialized inflammatory responses in the brain while avoiding global alterations in CNS function.
NuMA-microtubule interactions are critical for spindle orientation and the morphogenesis of diverse epidermal structures
Authors: Seldin Lindsey , Muroyama Andrew , Lechler Terry
Published: January 2016

Mitotic spindle orientation is used to generate cell fate diversity and drive proper tissue morphogenesis. A complex of NuMA and dynein/dynactin is required for robust spindle orientation in a number of cell types. Previous research proposed that cortical dynein/dynactin was sufficient to generate forces on astral microtubules (MTs) to orient the spindle, with NuMA acting as a passive tether. In this study, we demonstrate that dynein/dynactin is insufficient for spindle orientation establishment in keratinocytes and that NuMA’s MT-binding domain, which targets MT tips, is also required. Loss of NuMA-MT interactions in skin caused defects in spindle orientation and epidermal differentiation, leading to neonatal lethality. In addition, we show that NuMA-MT interactions are also required in adult mice for hair follicle morphogenesis and spindle orientation within the transit-amplifying cells of the matrix. Loss of spindle orientation in matrix cells results in defective differentiation of matrix-derived lineages. Our results reveal an additional and direct function of NuMA during mitotic spindle positioning, as well as a reiterative use of spindle orientation in the skin to build diverse structures.
Acceleration of degradation by highly accelerated stress test and air-included highly accelerated stress test in crystalline silicon photovoltaic modules
Authors: Suzuki Soh , Tanahashi Tadanori , Doi Takuya , Masuda Atsushi
Published: January 2016

We examined the effects of hyper-hygrothermal stresses with or without air on the degradation of crystalline silicon (c-Si) photovoltaic (PV) modules, to shorten the required duration of a conventional hygrothermal-stress test [i.e., the “damp heat (DH) stress test”, which is conducted at 85 °C/85% relative humidity for 1,000 h]. Interestingly, the encapsulant within a PV module becomes discolored under the air-included hygrothermal conditions achieved using DH stress test equipment and an air-included highly accelerated stress test (air-HAST) apparatus, but not under the air-excluded hygrothermal conditions realized using a highly accelerated stress test (HAST) machine. In contrast, the reduction in the output power of the PV module is accelerated irrespective of air inclusion in hyper-hygrothermal test atmosphere. From these findings, we conclude that the required duration of the DH stress test will at least be significantly shortened using air-HAST, but not HAST.
Structural, optical and dispersion properties of 5,10,15,20-tetraphenyl-21H,23H-porphyrin zinc thin films
Authors: Zeyada Hamdy M. , Makhlouf Mohamed M. , Ali Mohamed A.
Published: January 2016

The thin films of 5,10,15,20-tetraphenyl-21H,23H-porphyrin zinc, ZnTPP, were successfully prepared by the thermal evaporation technique. The structure formation and optical properties of ZnTPP thin films were studied. The surface morphology and structural characteristics of ZnTPP thin films were analyzed by atomic force microscopy (AFM) and X-ray diffraction (XRD) techniques, respectively. The optical constants of ZnTPP films were measured by spectrophotometer measurements of the transmittance and reflectance at a normal incidence of light in the spectral wavelength range from 200 to 2500 nm. The absorption spectrum of ZnTPP films showed four absorption bands, namely, the Q, B, N, and M bands. Anomalous dispersion was observed in the absorption region and normal dispersion occurred in the transparent region of the spectrum. We adopted the multi-oscillator and the single-oscillator models to interpret the results of anomalous and normal dispersion characteristics, respectively. The energy band gap of ZnTPP films was measured and the type of electron transition was determined to be the indirect allowed transition. The annealing process had an obvious effect on the morphology, structure, optical constants, and spectral dispersion parameters of ZnTPP thin films.
Comparative genomics ofSynechococcusand proposal of the new genusParasynechococcus
Authors: Coutinho Felipe , Tschoeke Diogo Antonio , Thompson Fabiano , Thompson Cristiane
Published: January 2016

Synechococcusis among the most important contributors to global primary productivity. The genomes of several strains of this taxon have been previously sequenced in an effort to understand the physiology and ecology of these highly diverse microorganisms. Here we present a comparative study ofSynechococcusgenomes. For that end, we developed GenTaxo, a program written in Perl to perform genomic taxonomy based on average nucleotide identity, average amino acid identity and dinucleotide signatures, which revealed that the analyzed strains are drastically distinct regarding their genomic content. Phylogenomic reconstruction indicated a division ofSynechococcusin two clades (i.e. Synechococcus and the new genus Parasynechococcus), corroborating evidences that this is in fact a polyphyletic group. By clustering protein encoding genes into homologue groups we were able to trace the Pangenome and core genome of both marine and freshwaterSynechococcusand determine the genotypic traits that differentiate these lineages.
Effects of temperature and host stage on the parasitization rate and offspring sex ratio ofAenasius bambawaleiHayat inPhenacoccus solenopsisTinsley
Authors: Zhang Juan , Huang Jun , Lu Yaobin , Xia Tianfeng
Published: January 2016

Temperature and host stage are important factors that determine the successful development of parasitoids.Aenasius bambawaleiHayat (Hymenoptera: Encyrtidae) is a primary parasitoid of the newly invasive mealybug,Phenacoccus solenopsisTinsley (Hemiptera: Pseudococcidae). The effects of temperature on the parasitic characteristics ofA. bambawaleihave seldom been investigated. In the study, we explored the effects of temperature, exposure time, and host stage on the parasitization rate and offspring sex ratio (female to male) ofA. bambawaleiunder laboratory conditions. The laboratory results showed that the successful parasitization rate ofA. bambawaleiincreased with higher temperatures and older host stages. When the parasitoids were exposed to 36 °C for 24 h, the parasitization rate of female adults (52%) was nearly two times that of 3rd instar nymphs. Additionally, heat stress duration and host stage resulted in an increase in the offspring sex ratio ofA. bambawalei. WhenA. bambawaleiwas exposed to 36 °C for 24 h, the offspring sex ratio increased dramatically to 81.78% compared with those exposed for 12 h, and it increased to 45.34% compared with those exposed for 16 h. The offspring sex ratio was clearly higher when the host stage was an adult female mealybug Our findings provide important guidance for the mass rearing and field releases ofA. bambawaleifor the management ofP. solenopsisin the future.
Non-invasive cortisol measurements as indicators of physiological stress responses in guinea pigs
Authors: Nemeth Matthias , Pschernig Elisabeth , Wallner Bernard , Millesi Eva
Published: January 2016

Non-invasive measurements of glucocorticoid (GC) concentrations, including cortisol and corticosterone, serve as reliable indicators of adrenocortical activities and physiological stress loads in a variety of species. As an alternative to invasive analyses based on plasma, GC concentrations in saliva still represent single-point-of-time measurements, suitable for studying short-term or acute stress responses, whereas fecal GC metabolites (FGMs) reflect overall stress loads and stress responses after a species-specific time frame in the long-term. In our study species, the domestic guinea pig, GC measurements are commonly used to indicate stress responses to different environmental conditions, but the biological relevance of non-invasive measurements is widely unknown. We therefore established an experimental protocol based on the animals’ natural stress responses to different environmental conditions and compared GC levels in plasma, saliva, and fecal samples during non-stressful social isolations and stressful two-hour social confrontations with unfamiliar individuals. Plasma and saliva cortisol concentrations were significantly increased directly after the social confrontations, and plasma and saliva cortisol levels were strongly correlated. This demonstrates a high biological relevance of GC measurements in saliva. FGM levels measured 20 h afterwards, representing the reported mean gut passage time based on physiological validations, revealed that the overall stress load was not affected by the confrontations, but also no relations to plasma cortisol levels were detected. We therefore measured FGMs in two-hour intervals for 24 h after another social confrontation and detected significantly increased levels after four to twelve hours, reaching peak concentrations already after six hours. Our findings confirm that non-invasive GC measurements in guinea pigs are highly biologically relevant in indicating physiological stress responses compared to circulating levels in plasma in the short- and long-term. Our approach also underlines the importance of detailed investigations on how to use and interpret non-invasive measurements, including the determination of appropriate time points for sample collections.
The Iflaviruses Sacbrood virus and Deformed wing virus evoke different transcriptional responses in the honeybee which may facilitate their horizontal or vertical transmission
Authors: Ryabov Eugene V. , Fannon Jessica M. , Moore Jonathan D. , Wood Graham R. , Evans David J.
Published: January 2016

Sacbrood virus (SBV) and Deformed wing virus (DWV) are evolutionarily related positive-strand RNA viruses, members of the Iflavirus group. They both infect the honeybee Apis mellifera but have strikingly different levels of virulence when transmitted orally. Honeybee larvae orally infected with SBV usually accumulate high levels of the virus, which halts larval development and causes insect death. In contrast, oral DWV infection at the larval stage usually causes asymptomatic infection with low levels of the virus, although high doses of ingested DWV could lead to DWV replicating to high levels. We investigated effects of DWV and SBV infection on the transcriptome of honeybee larvae and pupae using global RNA-Seq and real-time PCR analysis. This showed that high levels of SBV replication resulted in down-regulation of the genes involved in cuticle and muscle development, together with changes in expression of putative immune-related genes. In particular, honeybee larvae with high levels of SBV replication, with and without high levels of DWV replication, showed concerted up-regulated expression of antimicrobial peptides (AMPs), and down-regulated expression of the prophenoloxidase activating enzyme (PPAE) together with up-regulation of the expression of a putative serpin, which could lead to the suppression of the melanisation pathway. The effects of high SBV levels on expression of these immune genes were unlikely to be a consequence of SBV-induced developmental changes, because similar effects were observed in honeybee pupae infected by injection. In the orally infected larvae with high levels of DWV replication alone we observed no changes of AMPs or of gene expression in the melanisation pathway. In the injected pupae, high levels of DWV alone did not alter expression of the tested melanisation pathway genes, but resulted in up-regulation of the AMPs, which could be attributed to the effect of DWV on the regulation of AMP expression in response to wounding. We propose that the difference in expression of the honeybee immune genes induced by SBV and DWV may be an evolutionary adaptation to the different predominant transmission routes used by these viruses.
More for the Mind and Its Legacy
Authors: Lurie Steve , Goldbloom David S.
Published: January 2016

More For the Mind was published by the Canadian Mental Health Association in 1963. It reviewed the state of mental health services in Canada and called for transforming the delivery of mental health services from a neglected asylum-based system to a community-focused system where people could access services in general hospitals and the community. The article reviews the history of mental health services in Canada, the legacy of More for the Mind and the prospects for the reforms outlined in Changing Directions, Changing Lives.
An ocean bottom seismic observatory with near real‐time telemetry
Authors: Berger J. , Laske G. , Babcock J. , Orcutt J.
Published: January 2016

We describe a new technology that can provide near real‐time telemetry of sensor data from the ocean bottom without a moored buoy or a cable to shore. The breakthrough technology that makes this system possible is an autonomous surface vehicle called a Wave Glider developed by Liquid Robotics, Inc. of Sunnyvale, CA, which harvests wave and solar energy for motive and electrical power. We present results from several deployments of a prototype system that demonstrate the feasibility of this concept. We also demonstrated that a wave glider could tow a suitably designed ocean bottom package with acceptable loss of speed. With further development such a system could be deployed autonomously and provide real‐time telemetry of data from seafloor sensors.
Estimating time‐dependent connectivity in marine systems
Authors: Defne Zafer , Ganju Neil K. , Aretxabaleta Alfredo
Published: January 2016

Hydrodynamic connectivity describes the sources and destinations of water parcels within a domain over a given time. When combined with biological models, it can be a powerful concept to explain the patterns of constituent dispersal within marine ecosystems. However, providing connectivity metrics for a given domain is a three‐dimensional problem: two dimensions in space to define the sources and destinations and a time dimension to evaluate connectivity at varying temporal scales. If the time scale of interest is not predefined, then a general approach is required to describe connectivity over different time scales. For this purpose, we have introduced the concept of a “retention clock” that highlights the change in connectivity through time. Using the example of connectivity between protected areas within Barnegat Bay, New Jersey, we show that a retention clock matrix is an informative tool for multitemporal analysis of connectivity.
A revised picture of the atmospheric moisture residence time
Authors: Läderach Alexander , Sodemann Harald
Published: January 2016

Refined Lagrangian moisture source diagnostics are applied on an air mass transport climatology covering the period 1979–2013 to provide an estimate of the atmospheric moisture residence time. Our diagnostics yield an estimate of about 4–5 days for the global mean residence time, which is about half compared to depletion times that are commonly interpreted as proxies for the residence time. The discrepancies to depletion times are mainly explained by the fact that these are based on simplified representations of precipitation processes. The revised picture given by our results is supported by the overall consistency with the footprints of precipitation producing weather systems in different regions of the Earth.
Bias characterization of CrIS shortwave temperature sounding channels using fast NLTE model and GFS forecast field
Authors: Yin Mengtao
Published: January 2016

The strong nonlocal thermal equilibrium (NLTE) emission in the upper atmosphere impedes the usage of Cross‐track Infrared Sounder (CrIS) temperature channels near 4.3 µm in the operational data assimilation. This study explores the bias characteristics of those temperature channels near 4.3 µm with and without a fast NLTE model implemented in the Community Radiative Transfer Model (CRTM). It is shown that the biases of those temperature channels can reach up to 12 K and are dramatically reduced to below 4 K during daytime by the fast NLTE model with small differences from the nighttime biases. However, the biases after applying the NLTE correction remain large for CrIS upper atmospheric temperature channels during both daytime and nighttime. A further investigation suggests that the remaining biases in those temperature channels mainly originate from the cold biases in the stratospheric temperature profiles of National Center for Environmental Prediction Global Forecast System (GFS) forecasts as input to CRTM. The cold biases reach the maximum of about 8 K near the tropics at about 1 hPa, decreasing toward higher latitudes and lower altitudes.
The sensitivity of carbon exchanges in Great Plains grasslands to precipitation variability
Authors: Petrie M. D. , Brunsell N. A. , Vargas R. , Collins S. L. , Flanagan L. B. , Hanan N. P. , Litvak M. E. , Suyker A. E.
Published: January 2016

In the Great Plains, grassland carbon dynamics differ across broad gradients of precipitation and temperature, yet finer‐scale variation in these variables may also affect grassland processes. Despite the importance of grasslands, there is little information on how fine‐scale relationships compare between them regionally. We compared grassland C exchanges, energy partitioning and precipitation variability in eight sites in the eastern and western Great Plains using eddy covariance and meteorological data. During our study, both eastern and western grasslands varied between an average net carbon sink and a net source. Eastern grasslands had a moderate vapor pressure deficit (VPD = 0.95 kPa) and high growing season gross primary productivity (GPP = 1010 ± 218 g C m−2 yr−1). Western grasslands had a growing season with higher VPD (1.43 kPa) and lower GPP (360 ± 127 g C m−2 yr−1). Western grasslands were sensitive to precipitation at daily timescales, whereas eastern grasslands were sensitive at monthly and seasonal timescales. Our results support the expectation that C exchanges in these grasslands differ as a result of varying precipitation regimes. Because eastern grasslands are less influenced by short‐term variability in rainfall than western grasslands, the effects of precipitation change are likely to be more predictable in eastern grasslands because the timescales of variability that must be resolved are relatively longer. We postulate increasing regional heterogeneity in grassland C exchanges in the Great Plains in coming decades.
Combustion Synthesis
Authors: Liu Guanghua , Li Jiangtao , Chen Kexin
Published: January 2016

Combustion synthesis is used to synthesize useful materials via combustion reactions. Compared to many other material synthesis approaches, combustion synthesis is furnace‐free and more efficient, with negligible energy consumption, short processing times, large productivities, and low costs of production. The unique conditions of combustion synthesis, characterized by extremely high temperatures and rapid heating/cooling rates, offers tremendous possibilities for controlling the microstructure and synthesis of novel materials. To date, combustion synthesis has been used to produce a wide variety of inorganic materials, including metals, ceramics, and metal–ceramic composites, in different forms of powders, coatings, and bulks. Today, combustion synthesis is associated with many scientific disciplines, is applied to various industrial fields, and represents a promising branch of modern science and technology with an ever‐growing influence. In this chapter, a comprehensive introduction to combustion synthesis, from theory to practice, is provided. Initially, some basic concepts and fundamentals of the process are elucidated, with the essential parameters of combustion reactions, including adiabatic temperature, propagation velocity and stability of combustion wave, being explained based on homogeneous models. Heterogeneous and discrete combustion models are then described for heterogeneous reaction media. Finally, the reaction mechanism of combustion synthesis is discussed, along with improvements in experimental skills. The processing of combustion synthesis (and materials thus created) are also reviewed. The effects of the main parameters in routine processing of combustion synthesis are discussed for solid–solid and solid–gas reactions. Details of various hybrid processes based on combustion synthesis are then presented, with high‐gravity combustion synthesis as a particular example. Finally, solution combustion synthesis and gas combustion synthesis are introduced, with emphasis placed on the preparation of nanosized particles.
Scale‐Up in Combustion
Authors: Bolhàr‐Nordenkampf Markus
Published: January 2016

Scale‐up in combustion has been a fundamental driver in the past to utilize the economy of scale effect in industrial combustion plants. Several scaling methods have been used successfully in engineering applications to transfer the properties of smaller equipment onto larger equipment. Today, fluid dynamic scaling based on scaling criteria derived from fundamental fluid dynamic equations, describing the movement of the two‐phase medium in a fluidized bed reactor, can be performed with sufficient accuracy, using cold flow models. However, combustion scaling using laboratory data obtained from a small‐scale boiler inherits the difference that complete fluid dynamic similarity can never be obtained. In complete boiler design the main problem is the scale‐up of known features to very large sizes; scaling can then use elements already developed in similar size and employ them in multiple numbers to reach the required throughput. In bubbling fluidized bed technology the upscaling has reached a limit, while in circulating fluidized bed boilers the strong upscaling tendency shows a slower movement. The main challenges today are the substitution of an existing fuel with a more challenging counterpart, or the use of low‐grade fuel. This can cause severe problems in industrial‐sized plants, mainly in terms of fuel feeding, ash discharge, and the erosion and corrosion behaviors of the flue gases. Further challenges of today exists in the increase in pressure on the return of investment ofR&Dprojects, the high requirements on plant availability, even on prototypes, and the constant reduction inR&Dbudgets.
Smog Formation
Authors: Brimblecombe Peter
Published: January 2016

The historic transition from wood to coal as a fuel leads to primary pollutants such as carbon monoxide, polycyclic aromatic hydrocarbons, and soot. In addition, the Zeldovich cycle adds nitric oxides, while impurities in coal produce sulfur dioxide. By the late 19th century, winter smogs dominated the air of many cities where coal was used as a domestic fuel, and this sulfur dioxide was oxidized, acidifying the fog droplets. By contrast, modern winter smogs are often dominated by nitrogen oxides, although 21st century Northern China suffers severe winter pollution where coal makes a contribution, along with petroleum. A novel form of smog became evident in mid‐20th century Los Angeles, and involves nitrogen oxide chemistry promoted by the presence of volatile organic matter resulting from the use of petroleum‐based fuels in automobiles. As the formation of Los Angeles smog is complex, rather than to control emissions an improvement in air quality requires an understanding of atmospheric chemistry. In the past, pollution episodes have provided epidemiological evidence for enhanced death rates and respiratory complaints. However, in modern cites, fine particles that deposit deep into the lung alveoli can increase the risk of stroke or heart attack. Air pollutants can also damage building materials.
Gas Turbine Combustors
Authors: Kushari Abhijit
Published: January 2016

Gas turbine engines are widely used for power generation and aircraft propulsion due to their better efficiency, thrust‐to‐weight ratio, ease of startup and operation, and compactness. The basic gas generator, consisting of a compressor, a combustor and a turbine, is in the heart of every gas turbine engine. The compressor compresses the incoming air to which fuel is added and burned in the combustor. The turbine provides the power to operate the compressor. The design of a gas turbine combustor ensures that quite stringent and varied operational requirements are met efficiently for a wide range of operating conditions. The design also ensures complete combustion of the fuel inside a very short combustor, as well as substantially low levels of emissions per unit flow rate with respect to other engines. The basic operation of a gas turbine engine and its variants, the unique features of a gas turbine combustor and the emissions from gas turbine engines, with their dependence on operating conditions, are discussed in this chapter.
Fundamentals and Technology of Oxy‐Coal Combustion
Authors: Fujimori Toshiro , Ito Takamasa , Zhang Juwei
Published: January 2016

As one of the most attractive technologies for carbon capture, oxy‐fuel combustion of coal has been studied worldwide. Some important results of fundamental studies and practical systems of oxy‐fuel combustion are introduced in this chapter. According to the results of fundamental experiments, a slower flame propagation velocity in a O2/CO2atmosphere requires a higher O2concentration to obtain a stable combustion in oxy‐fuel mode compared to air mode. CO2and H2O gasification each have effects on reducing the char particle temperature and increasing the char consumption rate. In oxy‐fuel mode, gasification reactions between char and CO2or H2O can result in a high devolatilization rate and a clearly different char structure. As with simulations of heat transfer in the boiler for oxy‐fuel combustion, the new weighted sum of gray‐gases model for calculating gas radiation properties should be developed to adapt to very high concentrations of CO2and H2O in the flue gas. However, particle radiation generally plays a more important role than gas radiation. Computational fluid dynamics simulation data obtained with the Callide furnace have shown an oxy‐fuel combustion of 27 vol.% O2with flue gas recycling to have a similar heat absorption to air combustion. Fundamental and applications research are still required, however, to optimize boiler design and system configurations.
Adaptive model‐based event‐triggered sliding mode control
Authors: Incremona Gian Paolo , Ferrara Antonella
Published: January 2016

This paper addresses the design of a model‐based event‐triggered sliding mode control strategy of adaptive type. The overall proposal can be regarded as a networked control scheme, because one of the design objectives is to reduce the number of transmissions of the plant state over the network used to construct the control loop. The key idea consists in using the actual plant state or the state of a suitably updated nominal model of the plant to generate the control variable, depending on the magnitude of the sliding variable. The proposed adaptive control scheme proves to be capable of steering the sliding variable to a boundary layer of the sliding manifold in finite time, in spite of the presence of bounded uncertainties with unknown bounds. When the sliding variable is confined within the boundary layer, the nominal model state is used to compute the control variable. Then, a continuous control can be analytically determined and applied, which provides a beneficial chattering alleviation effect. The proposed networked control scheme is theoretically analyzed and assessed in simulation with satisfactory results. Copyright © 2016 John Wiley & Sons, Ltd.
Growth of Large Crystalline Grains of Vanadyl‐Phthalocyanine without Epitaxy on Graphene
Authors: Marsden Alexander J. , Rochford Luke A. , Wood Dawn , Ramadan Alexandra J. , Laker Zachary P. L. , Jones Tim S. , Wilson Neil R.
Published: January 2016

The performance of organic semiconductor thin films in electronic devices is related to their crystal structure and morphology, with charge transport mobility dependent on the degree of crystallinity and on the crystallographic orientation. Here organic molecular beam deposition of vanadyl phthalocyanine is studied on graphene and it is shown that crystalline grains up to several micrometers across can be formed at substrate temperatures of 155 °C, compared to room temperature grain sizes of ≈30 nm. Transmission electron microscopy confirms the presence of long range order at elevated substrate temperatures and reveals that the molecules are stacked in an edge‐on orientation, but are not epitaxially aligned to the graphene. The crystalline grain sizes are significantly larger on graphene than on disordered substrates such as graphene oxide and silicon oxide. The effect on charge transport is probed by conducting atomic force microscopy, with the high temperature films on graphene showing increased mobility and uniformity and decreased trap density. These results illustrate an important advantage for the integration of graphene electrodes with organic semiconductor devices: the homogeneous surface of graphene results in high diffusion and low nucleation rates for thin film growth, encouraging the formation of highly crystalline films even with nonepitaxial growth.
Long Circulation Red‐Blood‐Cell‐Mimetic Nanoparticles with Peptide‐Enhanced Tumor Penetration for Simultaneously Inhibiting Growth and Lung Metastasis of Breast Cancer
Authors: Su Jinghan , Sun Huiping , Meng Qingshuo , Yin Qi , Tang Shan , Zhang Pengcheng , Chen Yi , Zhang Zhiwen , Yu Haijun , Li Yaping
Published: January 2016

Limited blood circulation and poor tumor penetration are two main obstacles hampering the clinical translation of conventional nanosized drug delivery systems (NDDS). Here, red‐blood‐cell (RBC)‐mimetic nanoparticles (NPs) with long circulation and peptide‐enhanced tumor penetration for treating metastatic breast cancer are reported. The RBC‐mimetic NPs are composed of a paclitaxel (PTX)‐loaded polymeric core and a hydrophilic RBC vesicle shell. The RBC‐mimetic NPs display dramatically elongated blood circulation with an elimination half time of 32.8 h, 5.8‐fold higher than that of the parental polymeric NPs (i.e., 5.6 h). Moreover, the experimental results demonstrate that the tumor penetration ability of the RBC‐mimetic NPs can be significantly improved by coadministrating with a tumor‐penetrating peptide iRGD. Antitumor studies using a metastatic 4T1 breast tumor model show that RBC‐mimetic NPs in combination with iRGD significantly inhibit over 90% of the tumor growth and suppress 95% of the lung metastasis, much more efficient than PTX‐loaded polymer NP alone or the combination of polymer NPs and iRGD. The results reveal the importance of both long circulation and tumor penetration of nanosized drugs for efficient cancer therapy, which can provide a new insight for NDDS design.
Synthesis and Characterization of New pH‐Sensitive Hydrogels Based on Poly(glycidyl methacrylate‐co‐maleic anhydride)
Authors: Shohraty Farhad , Moghadam Peyman Najafi , Fareghi Amir Reza , Movagharnezhad Nasim , Khalafy Jabbar
Published: January 2016

In the present study, two new kinds of modified poly(glycidyl methacrylate‐co‐maleic anhydride) hydrogels have been prepared and studied as pH‐sensitive drug carriers. At first, poly(glycidyl methacrylate‐co‐maleic anhydride) (PGMA‐co‐MA) was prepared via free‐radical polymerization of glycidyl methacrylate and maleic anhydride in the presence of benzoyl peroxide as an initiator. Then the copolymer was modified with two different kinds of amino‐containing compounds, 2‐aminopyridine and 4‐aminobutyric acid. Samples were characterized by FT‐IR and TGA analysis. Besides, the water‐swelling behavior was studied to determine the approximate swelling capacity. Then as a model, Cefotaxime drug was loaded on both hydrogels, and the release studies were carried out at different pH values (3, 7, and 8, respectively). It was concluded from the results that the amino acid–modified hydrogel has a more controlled release rate than the aminopyridine‐modified hydrogel. But generally, both of these hydrogels showed acceptable response to different pH values and can be employed as pH‐sensitive drug carriers.
Amorphous‐Si‐Based Resistive Switching Memories with Highly Reduced Electroforming Voltage and Enlarged Memory Window
Authors: Qian Kai , Nguyen Viet Cuong , Chen Tupei , Lee Pooi See
Published: January 2016

Amorphous Si (a‐Si) based memory devices that offer significant improvement in switching performance are fabricated by inserting a gold nanoparticles (Au NPs) monolayer between the amorphous Si and inert bottom electrodes. It is demonstrated that the Au NPs‐interlayer amorphous Si memory devices deliver great improvements in lowering the electroforming voltage as well as enhancing the ON/OFF ratio, as compared to a pure amorphous Si memory structure. The switching mechanism is due to the modified electric field distribution with the insertion of Au NPs, which can directly affect the dynamic transport of ions and lead to the change of filament growth. Transmission electron microscopy (TEM) is used to directly capture the filaments growth process in these two types of memory devices to verify the evolution of conductive filament (CF). In addition, it is also demonstrated that the Au NPs‐interlay amorphous Si memory fabricated on a flexible substrate can maintain low electroforming voltage and high ON/OFF ratio. This fabrication approach offers a versatile structural platform for next‐generation memory applications with enhancement of the switching properties.
Origin of the S‐Shaped JV Curve and the Light‐Soaking Issue in Inverted Organic Solar Cells
Authors: Sundqvist Anton , Sandberg Oskar J. , Nyman Mathias , Smått Jan‐Henrik , Österbacka Ronald
Published: January 2016

Inverted organic solar cells generally exhibit a strong s‐shaped kink in the current–voltage characteristics (JV curve) that may be removed by exposure to UV light (light‐soaking) leading to a drastically improved performance. Using in‐device characterization methods the origin of the light‐soaking issue in inverted solar cells employing titanium dioxide (TiO2) as an electron selective layer is clarified. An injected hole reservoir accumulated at the TiO2/organic interface of the pristine device is observed from extraction current transients; the hole reservoir increases the recombination and results in an s‐shape in the JV curve of pristine devices. The hole reservoir and the s‐shape is a result of the energetics at the selective contact in the pristine device; the effect of UV exposure is to decrease the work function of the indium tin oxide/TiO2‐contact, increasing the built‐in potential. This hinders the build‐up of the hole reservoir and the s‐shape is removed. The proposed model is in excellent agreement with drift‐diffusion simulations.
Optimal reuse of flowback wastewater in hydraulic fracturing including seasonal and environmental constraints
Authors: Lira‐Barragán Luis Fernando , Ponce‐Ortega José María , Serna‐González Medardo , El‐Halwagi Mahmoud M.
Published: January 2016

This article presents a mathematical programing formulation for the optimal management of flowback water in shale gas wells. The formulation accounts for the time‐based generation of the flowback water, the options for treatment, storage, reuse, and disposal. The economic and environmental objectives are considered. The economic objective function is aimed at determining the minimum cost for the fresh water, treatment, storage, disposals, and transportation. The environmental objectives account for the fresh water usage and wastewater discharge. To carry out the water integration, a reuse network including treatment is proposed. Additionally, the model considers seasonal fluctuations in the fresh water availability. A given scheduling for the completion phases of the wells is required to implement the methodology. Finally, an example problem is presented to show the applicability of the proposed methodology. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1634–1645, 2016
Auricular ossification: A newly recognized feature of osteoprotegerin‐deficiency juvenile Paget disease
Authors: Gottesman Gary S. , Madson Katherine L. , McAlister William H. , Nenninger Angela , Wenkert Deborah , Mumm Steven , Whyte Michael P.
Published: January 2016

We report auricular ossification (AO) affecting the elastic cartilage of the ear as a newly recognized feature of osteoprotegerin (OPG)‐deficiency juvenile Paget disease (JPD). AO and auricular calcification refer interchangeably to rigid pinnae, sparing the ear lobe, from various etiologies. JPD is a rare Mendelian disorder characterized by elevated serum alkaline phosphatase activity accompanied by skeletal pain and deformity from rapid bone turnover. Autosomal recessive transmission of loss‐of‐function mutations within TNFRSF11B encoding OPG accounts for most JPD (JPD1). JPD2 results from heterozygous constitutive activation of TNFRSF11A encoding RANK. Other causes of JPD remain unknown. In 2007, we reported a 60‐year‐old man with JPD1 who described hardening of his external ears at age 45 years, after 4 years of treatment with bisphosphonates (BPs). Subsequently, we noted rigid pinnae in a 17‐year‐old boy and 14‐year‐old girl, yet pliable pinnae in a 12‐year‐old boy, each with JPD1 and several years of BP treatment. Cranial imaging indicated cortical bone within the pinnae of both teenagers. Radiologic studies of our three JPD patients without mutations in TNFRSF11B showed normal auricles. Review of the JPD literature revealed possible AO in several reports. Two of our JPD1 patients had experienced difficult tracheal intubation, raising concern for mineralization of laryngeal elastic cartilage. Thus, AO is a newly recognized feature of JPD1, possibly exacerbated by BP treatment. Elastic cartilage at other sites in JPD1 might also ossify, and warrants investigation. © 2016 Wiley Periodicals, Inc.
Katalytische enantioselektive Funktionalisierung von nichtaktivierten terminalen Alkenen
Authors: Coombs John R. , Morken James P.
Published: January 2016

Terminale Alkene sind leicht verfügbare Verbindungen, die in der chemischen Industrie in Form von α‐Olefinen sowie als Produkte vieler gängiger Synthesereaktionen anfallen. Die organischen Transformationen solcher Alkene gehören zu den am besten untersuchten Reaktionen in der chemischen Synthese, allerdings kennt man nur relativ wenige Reaktionen, in denen nichtaktivierte terminale Alkene katalytisch und enantioselektiv umgesetzt werden. In diesem Kurzaufsatz stellen wir diejenigen Fälle vor, in denen die Stereokontrolle in katalytischen Reaktionen von 1‐Alkenen ausreicht, um sie für asymmetrische Synthesen nutzbar zu machen.
Synthesis and Biological Evaluation of Bromo‐ and Fluorodanicalipin A
Authors: Fischer Stefan , Huwyler Nikolas , Wolfrum Susanne , Carreira Erick M.
Published: January 2016

We disclose the syntheses of (+)‐bromodanicalipin A as well as (±)‐fluorodanicalipin A. The relative configuration and ground‐state conformation in solution of both molecules was secured by J‐based configuration analysis which revealed that these are identical to natural danicalipin A. Furthermore, preliminary toxicological investigations suggest that the adverse effect of danicalipin A may be due to the lipophilicity of the halogens.
Polyoxometalate‐Driven Self‐Assembly of Short Peptides into Multivalent Nanofibers with Enhanced Antibacterial Activity
Authors: Li Jingfang , Chen Zhijun , Zhou Mengcheng , Jing Jiangbo , Li Wen , Wang Yang , Wu Lixin , Wang Liyan , Wang Yanqiu , Lee Myongsoo
Published: January 2016

Multivalent peptide nanofibers have attracted intense attention as promising platforms, but the fabrication of those nanofibers is mainly dependent on the spontaneous assembly of β‐sheet peptides. Herein we report an alternative approach to the creation of nanofibers: the polyoxometalate‐driven self‐assembly of short peptides. The resultant nanofibers with concentrated positive charges are excellent multivalent ligands for binding with bacterial cells and thus lead to a salient improvement in bioactivity.
Catalytic Enantioselective Functionalization of Unactivated Terminal Alkenes
Authors: Coombs John R. , Morken James P.
Published: January 2016

Terminal alkenes are readily available functional groups which appear in α‐olefins produced by the chemical industry, and they appear in the products of many contemporary synthetic reactions. While the organic transformations that apply to alkenes are amongst the most studied reactions in all of chemical synthesis, the number of reactions that apply to nonactivated terminal alkenes in a catalytic enantioselective fashion is small in number. This Minireview highlights the cases where stereocontrol in catalytic reactions of 1‐alkenes is high enough to be useful for asymmetric synthesis.
Construction of Insulin 18‐mer Nanoassemblies Driven by Coordination to Iron(II) and Zinc(II) Ions at Distinct Sites
Authors: Munch Henrik K. , Nygaard Jesper , Christensen Niels Johan , Engelbrekt Christian , Østergaard Mads , Porsgaard Trine , Hoeg‐Jensen Thomas , Zhang Jingdong , Arleth Lise , Thulstrup Peter W. , Jensen Knud J.
Published: January 2016

Controlled self‐assembly (SA) of proteins offers the possibility to tune their properties or to create new materials. Herein, we present the synthesis of a modified human insulin (HI) with two distinct metal‐ion binding sites, one native, the other abiotic, enabling hierarchical SA through coordination with two different metal ions. Selective attachment of an abiotic 2,2′‐bipyridine (bipy) ligand to HI, yielding HI–bipy, enabled ZnII‐binding hexamers to SA into trimers of hexamers, [[HI–bipy]6]3, driven by octahedral coordination to a FeII ion. The structures were studied in solution by small‐angle X‐ray scattering and on surfaces with AFM. The abiotic metal ligand had a higher affinity for FeII than ZnII ions, enabling control of the hexamer formation with ZnII and the formation of trimers of hexamers with FeII ions. This precise control of protein SA to give oligomers of oligomers provides nanoscale structures with potential applications in nanomedicine.
Metal Free Bi(hetero)aryl Synthesis: A Benzyne Truce–Smiles Rearrangement
Authors: Holden Catherine M. , Sohel Shariar M. A. , Greaney Michael F.
Published: January 2016

A new benzyne transformation is described that affords versatile biaryl structures without recourse to transition‐metal catalysis or stoichiometric amounts of organometallic building blocks. Aryl sulfonamides add to benzyne upon fluoride activation, and then undergo an aryl Truce–Smiles rearrangement to afford biaryls with sulfur dioxide extrusion. The reaction proceeds under simple reaction conditions and has excellent scope for the synthesis of sterically hindered atropisomeric biaryl amines.
Enantioselective Total Synthesis of Terreumols A and C from the Mushroom Tricholoma terreum
Authors: Frichert Alex , Jones Peter G. , Lindel Thomas
Published: January 2016

The cytotoxic meroterpenoids terreumol A and C from the grey knight mushroom Tricholoma terreum were synthesized for the first time. The key step of the enantioselective total synthesis of terreumol C is a ring‐closing metathesis to form a trisubstituted Z double bond embedded in the 10‐membered ring of the [8.4.0] bicycle. Interestingly, the presence of a free hydroxy group in the metathesis precursor prevents cyclization and favors cross metathesis. (−)‐Terreumol C was converted into (−)‐terreumol A by diastereoselective epoxidation. Starting from 2‐bromo‐3,5‐dimethoxybenzaldehyde, 14 steps with an overall yield of 23 % are needed for the synthesis of (−)‐terreumol A. X‐ray analysis of the benzoquinone analogue of terreumol A provides independent proof of the absolute configuration.