bluuebunny/crossref_metadata_2025 huggingface dataset:
Specific cancer-associated mutations in the switch III region of Ras increase tumorigenicity by nanocluster augmentation
Authors: Šolman Maja , Ligabue Alessio , Blaževitš Olga , Jaiswal Alok , Zhou Yong , Liang Hong , Lectez Benoit , Kopra Kari , Guzmán Camilo , Härmä Harri , Hancock John F , Aittokallio Tero , Abankwa Daniel
Published: August 2015

Hotspot mutations of Ras drive cell transformation and tumorigenesis. Less frequent mutations in Ras are poorly characterized for their oncogenic potential. Yet insight into their mechanism of action may point to novel opportunities to target Ras. Here, we show that several cancer-associated mutations in the switch III region moderately increase Ras activity in all isoforms. Mutants are biochemically inconspicuous, while their clustering into nanoscale signaling complexes on the plasma membrane, termed nanocluster, is augmented. Nanoclustering dictates downstream effector recruitment, MAPK-activity, and tumorigenic cell proliferation. Our results describe an unprecedented mechanism of signaling protein activation in cancer.
Down-regulation of TORC2-Ypk1 signaling promotes MAPK-independent survival under hyperosmotic stress
Authors: Muir Alexander , Roelants Françoise M , Timmons Garrett , Leskoske Kristin L , Thorner Jeremy
Published: August 2015

In eukaryotes, exposure to hypertonic conditions activates a MAPK (Hog1 in Saccharomyces cerevisiae and ortholog p38 in human cells). In yeast, intracellular glycerol accumulates to counterbalance the high external osmolarity. To prevent glycerol efflux, Hog1 action impedes the function of the aquaglyceroporin Fps1, in part, by displacing channel co-activators (Rgc1/2). However, Fps1 closes upon hyperosmotic shock even in hog1∆ cells, indicating another mechanism to prevent Fps1-mediated glycerol efflux. In our prior proteome-wide screen, Fps1 was identified as a target of TORC2-dependent protein kinase Ypk1 (Muir et al., 2014). We show here that Fps1 is an authentic Ypk1 substrate and that the open channel state of Fps1 requires phosphorylation by Ypk1. Moreover, hyperosmotic conditions block TORC2-dependent Ypk1-mediated Fps1 phosphorylation, causing channel closure, glycerol accumulation, and enhanced survival under hyperosmotic stress. These events are all Hog1-independent. Our findings define the underlying molecular basis of a new mechanism for responding to hypertonic conditions.
FAK/PYK2 promotes the Wnt/β-catenin pathway and intestinal tumorigenesis by phosphorylating GSK3β
Authors: Gao Chenxi , Chen Guangming , Kuan Shih-Fan , Zhang Dennis Han , Schlaepfer David D , Hu Jing
Published: August 2015

Aberrant activation of Wnt/β-catenin signaling plays an unequivocal role in colorectal cancer, but identification of effective Wnt inhibitors for use in cancer remains a tremendous challenge. New insights into the regulation of this pathway could reveal new therapeutic point of intervention, therefore are greatly needed. Here we report a novel FAK/PYK2/GSK3βY216/β-catenin regulation axis: FAK and PYK2, elevated in adenomas in APCmin/+ mice and in human colorectal cancer tissues, functioned redundantly to promote the Wnt/β-catenin pathway by phosphorylating GSK3βY216 to reinforce pathway output—β-catenin accumulation and intestinal tumorigenesis. We previously showed that Wnt-induced β-catenin accumulation requires Wnt-induced GSK3β/β-TrCP interaction; the current study revealed that phosphorylation of GSK3βY216 was a molecular determinant of GSK3β recruitment of β-TrCP. Pharmacological inhibition of FAK/PYK2 suppressed adenoma formation in APCmin/+ mice accompanied with reduced intestinal levels of phospho-GSK3βY216 and β-catenin, indicating that FAK/PYK2/GSK3βY216 axis is critical for the activation of Wnt/β-catenin signaling in APC driven intestinal tumorigenesis.
Hürthle cell adenoma diagnosed by core needle biopsy in a male patient
Authors: Desai A , Peterson SE , Raiser F , Marx RJ , Wilner R
Published: August 2015

Huuml;rthle cell adenomas (HCAs) are a rare and potentially lethal variant of follicular tumors of the thyroid. Considerable controversy exists regarding potential risk factors, diagnosis, and treatment of HCAs. The authors report the case of a 38-year-old male patient with an 8.3 cm x 3.5 cm HCA. Diagnosis was made preoperatively from a core needle biopsy and confirmed postoperatively on frozen section. Treatment consisted of a right lobectomy.
Whither field hydrology? The need for discovery science and outrageous hydrological hypotheses
Authors: Burt T. P. , McDonnell J. J.
Published: August 2015

Field hydrology is on the decline. Meanwhile, the need for new field‐derived insight into the age, origin and pathway of water in the headwaters, where most runoff is generated, is more needed than ever. Water Resources Research (WRR) has included some of the most influential papers in field‐based runoff process understanding, particularly in the formative years when the knowledge base was developing rapidly. Here we take advantage of this 50th anniversary of the journal to highlight a few of these important field‐based papers and show how field scientists have posed strong and sometimes outrageous hypotheses—approaches so needed in an era of largely model‐only research. We chronicle the decline in field work and note that it is not only the quantity of field work that is diminishing but its character is changing too: from discovery science to data collection for model parameterization. While the latter is a necessary activity, the loss of the former is a major concern if we are to advance the science of watershed hydrology. We outline a vision for field research to seek new fundamental understanding, new mechanistic explanations of how watershed systems work, particularly outside the regions of traditional focus.
High emission rate of sulfuric acid from Bezymianny volcano, Kamchatka
Authors: Zelenski Michael , Taran Yuri , Galle Bo
Published: August 2015

High concentrations of primary sulfuric acid (H2SO4) in fumarolic gases and high emission rate of sulfuric acid aerosol in the plume were measured at Bezymianny volcano, an active dome‐growing andesitic volcano in central Kamchatka. Using direct sampling, filter pack sampling, and differential optical absorption spectroscopy measurements, we estimated an average emission of H2SO4 at 243 ± 75 t/d in addition to an average SO2 emission of 212 ± 65 t/d. The fumarolic gases of Bezymianny correspond to arc gases released by several magma bodies at different stages of degassing and contain 25–92% of entrained air. H2SO4 accounts for 6–87 mol% of the total sulfur content, 42.8 mol% on average, and SO2 is the rest. The high H2SO4 in Bezymianny fumaroles can be explained by catalytic oxidation of SO2 inside the volcanic dome. Because sulfate aerosol is impossible to measure remotely, the total sulfur content in a plume containing significant H2SO4 may be seriously underestimated.
Solar wind conditions leading to efficient radiation belt electron acceleration: A superposed epoch analysis
Authors: Li W. , Thorne R. M. , Bortnik J. , Baker D. N. , Reeves G. D. , Kanekal S. G. , Spence H. E. , Green J. C.
Published: August 2015

Determining preferential solar wind conditions leading to efficient radiation belt electron acceleration is crucial for predicting radiation belt electron dynamics. Using Van Allen Probes electron observations (>1 MeV) from 2012 to 2015, we identify a number of efficient and inefficient acceleration events separately to perform a superposed epoch analysis of the corresponding solar wind parameters and geomagnetic indices. By directly comparing efficient and inefficient acceleration events, we clearly show that prolonged southward Bz, high solar wind speed, and low dynamic pressure are critical for electron acceleration to >1 MeV energies in the heart of the outer radiation belt. We also evaluate chorus wave evolution using the superposed epoch analysis for the identified efficient and inefficient acceleration events and find that chorus wave intensity is much stronger and lasts longer during efficient electron acceleration events, supporting the scenario that chorus waves play a key role in MeV electron acceleration.
On solar geoengineering and climate uncertainty
Authors: MacMartin Douglas G. , Kravitz Ben , Rasch Philip J.
Published: August 2015

Uncertain climate system response has been raised as a concern regarding solar geoengineering. We explore the effects of geoengineering on one source of climate system uncertainty by evaluating the intermodel spread across 12 climate models participating in the Geoengineering Model Intercomparison project. The model spread in simulations of climate change and the model spread in the response to solar geoengineering are not additive but rather partially cancel. That is, the model spread in regional temperature and precipitation changes is reduced with CO2 and a solar reduction, in comparison to the case with increased CO2 alone. Furthermore, differences between models in their efficacy (the relative global mean temperature effect of solar versus CO2 radiative forcing) explain most of the regional differences between models in their response to an increased CO2 concentration that is offset by a solar reduction. These conclusions are important for clarifying geoengineering risks regarding uncertainty.
Ion acceleration dependence on magnetic shear angle in dayside magnetopause reconnection
Authors: Vines S. K. , Fuselier S. A. , Trattner K. J. , Petrinec S. M. , Drake J. F.
Published: August 2015

Magnetic reconnection at the Earth's magnetopause plays an important role in magnetospheric dynamics. Understanding the dynamics requires theory and observations. Previous theoretical work suggests that for no guide field, ions in the exhaust region on the magnetosheath side of the boundary counterstream with a velocity separation that is twice the upstream Alfvén speed (vA) and that the counterstreaming velocity decreases with increasing guide field. These theoretical predictions are tested for reconnection at the Earth's magnetopause using observations from the Cluster spacecraft. The difference between the incident and reflected ion velocities (vsep) in the magnetosheath boundary layer ion populations is used to determine the exhaust velocity. The ratio of vsep over twice the Alfvén speed (RV = vsep/2vA,L) is predicted to approach 1 for reconnection with shear angles near 180° (no guide field) but is observed to reach a value of approximately 0.84 for the magnetopause crossings analyzed with shear angles near 180°. This value is consistent with previous observations of ion velocities from reconnection at the magnetopause investigated using the Walén relation. While magnetic shear angle can contribute to the disagreement between observations and the Walén relation, it does not play a large role, given the reduced ratio for the events near 180° in this study.
The 3 May 2006 (Mw 8.0) and 19 March 2009 (Mw 7.6) Tonga earthquakes: Intraslab compressional faulting below the megathrust
Authors: Meng Qingjun , Heeszel David S. , Ye Lingling , Lay Thorne , Wiens Douglas A. , Jia Minghai , Cummins Phil R.
Published: August 2015

The Tonga subduction zone is among the most seismically active regions and has the highest plate convergence rate in the world. However, recorded thrust events confidently located on the plate boundary have not exceeded Mw 8.0, and the historic record suggests low seismic coupling along the arc. We analyze two major thrust fault earthquakes that occurred in central Tonga in 2006 and 2009. The 3 May 2006 Mw 8.0 event has a focal mechanism consistent with interplate thrusting, was located west of the trench, and caused a moderate regional tsunami. However, long‐period seismic wave inversions and finite‐fault modeling by joint inversion of teleseismic body waves and local GPS static offsets indicate a slip distribution centered ~65 km deep, about 30 km deeper than the plate boundary revealed by locations of aftershocks, demonstrating that this was an intraslab event. The aftershock locations were obtained using data from seven temporary seismic stations deployed shortly after the main shock, and most lie on the plate boundary, not on either nodal plane of the deeper main shock. The fault plane is ambiguous, and investigation of compound rupture involving coseismic slip along the megathrust does not provide a better fit, although activation of megathrust faulting is responsible for the aftershocks. The 19 March 2009 Mw 7.6 compressional faulting event occurred below the trench; finite‐fault and W‐phase inversions indicate an intraslab, ~50 km deep centroid, with ambiguous fault plane. This event also triggered small megathrust faulting. There continues to be a paucity of large megathrust earthquakes in Tonga.
Distinguishing induced seismicity from natural seismicity in Ohio: Demonstrating the utility of waveform template matching
Authors: Skoumal Robert J. , Brudzinski Michael R. , Currie Brian S.
Published: August 2015

This study investigated the utility of multistation waveform cross correlation to help discern induced seismicity. Template matching was applied to all Ohio earthquakes cataloged since the arrival of nearby EarthScope TA stations in late 2010. Earthquakes that were within 5 km of fluid injection activities in regions that lacked previously documented seismicity were found to be swarmy. Moreover, the larger number of events produced by template matching for these swarmy sequences made it easier to establish more detailed temporal and spatial relationships between the seismicity and fluid injection activities, which is typically required for an earthquake to be considered induced. Study results detected three previously documented induced sequences (Youngstown, Poland Township, and Harrison County) and provided evidence that suggests two additional cases of induced seismicity (Belmont/Guernsey County and Washington County). Evidence for these cases suggested that unusual swarm‐like behaviors in regions that lack previously documented seismicity can be used to help distinguish induced seismicity, complementing the traditional identification of an anthropogenic source spatially and temporally correlated with the seismicity. In support of this finding, we identified 17 additional cataloged earthquakes in regions of previously documented seismicity and away from disposal wells or hydraulic fracturing that returned very few template matches. The lack of swarminess helps to indicate that these events are most likely naturally occurring.
Main eddy vertical structures observed in the four major Eastern Boundary Upwelling Systems
Authors: Pegliasco Cori , Chaigneau Alexis , Morrow Rosemary
Published: August 2015

In the four major Eastern Boundary Upwelling Systems (EBUS), mesoscale eddies are known to modulate the biological productivity and transport near‐coastal seawater properties toward the offshore ocean, however little is known about their main characteristics and vertical structure. This study combines 10 years of satellite‐altimetry data and Argo float profiles of temperature and salinity, and our main goals are (i) to describe the main surface characteristics of long‐lived eddies formed in each EBUS and their evolution, and (ii) to depict the main vertical structure of the eddy‐types that coexist in these regions. A clustering analysis of the Argo profiles surfacing within the long‐lived eddies of each EBUS allows us to determine the proportion of surface and subsurface‐intensified eddies in each region, and to describe their vertical structure in terms of temperature, salinity and dynamic height anomalies. In the Peru‐Chile Upwelling System, 55% of the sampled anticyclonic eddies (AEs) have subsurface‐intensified maximum temperature and salinity anomalies below the seasonal pycnocline, whereas 88% of the cyclonic eddies (CEs) are surface‐intensified. In the California Upwelling System, only 30% of the AEs are subsurface‐intensified and all of the CEs show maximum anomalies above the pycnocline. In the Canary Upwelling System, ∼40% of the AEs and ∼60% of the CEs are subsurface‐intensified with maximum anomalies extending down to 800 m depth. Finally, the Benguela Upwelling System tends to generate ∼40–50% of weak surface‐intensified eddies and ∼50–60% of much stronger subsurface‐intensified eddies with a clear geographical distribution. The mechanisms involved in the observed eddy vertical shapes are discussed.
Precipitation efficiency derived from isotope ratios in water vapor distinguishes dynamical and microphysical influences on subtropical atmospheric constituents
Authors: Bailey A. , Nusbaumer J. , Noone D.
Published: August 2015

With water vapor and clouds expected to effect significant feedbacks on climate, moisture transport through convective processes has important implications for future temperature change. The precipitation efficiency—the ratio of the rates at which precipitation and condensation form (e = P/C)—is useful for characterizing how much boundary layer moisture recycles through precipitation versus mixes into the free troposphere through cloud detrainment. Yet it is a difficult metric to constrain with traditional observational techniques. This analysis characterizes the precipitation efficiency of convection near the Big Island of Hawaii, USA, using a novel tracer: isotope ratios in water vapor. The synoptic circulation patterns associated with high and low precipitation efficiency are identified, and the importance of large‐scale dynamics and local convective processes in regulating vertical distributions of atmospheric constituents important for climate is evaluated. The results suggest that high e days are correlated with plume‐like transport originating from the relatively clean tropics, while low e days are associated with westerly transport, generated by a branching of the jet stream. Differences in transport pathway clearly modify background concentrations of water vapor and other trace gases measured at Mauna Loa Observatory; however, local convective processes appear to regulate aerosols there. Indeed, differences between observed and simulated diurnal cycles of particle number concentration indicate that precipitation scavenges aerosols and possibly facilitates new particle formation when e is high. As measurements of isotope ratios in water vapor expand across the subtropics, the techniques presented here can further our understanding of how synoptic weather, precipitation processes, and climate feedbacks interrelate.
Comprehensive evaluation of multisatellite precipitation estimates over India using gridded rainfall data
Authors: Sunilkumar K. , Narayana Rao T. , Saikranthi K. , Purnachandra Rao M.
Published: August 2015

This study presents a comprehensive evaluation of five widely used multisatellite precipitation estimates (MPEs) against 1° × 1° gridded rain gauge data set as ground truth over India. One decade observations are used to assess the performance of various MPEs (Climate Prediction Center (CPC)‐South Asia data set, CPC Morphing Technique (CMORPH), Precipitation Estimation From Remotely Sensed Information Using Artificial Neural Networks, Tropical Rainfall Measuring Mission's Multisatellite Precipitation Analysis (TMPA‐3B42), and Global Precipitation Climatology Project). All MPEs have high detection skills of rain with larger probability of detection (POD) and smaller “missing” values. However, the detection sensitivity differs from one product (and also one region) to the other. While the CMORPH has the lowest sensitivity of detecting rain, CPC shows highest sensitivity and often overdetects rain, as evidenced by large POD and false alarm ratio and small missing values. All MPEs show higher rain sensitivity over eastern India than western India. These differential sensitivities are found to alter the biases in rain amount differently. All MPEs show similar spatial patterns of seasonal rain bias and root‐mean‐square error, but their spatial variability across India is complex and pronounced. The MPEs overestimate the rainfall over the dry regions (northwest and southeast India) and severely underestimate over mountainous regions (west coast and northeast India), whereas the bias is relatively small over the core monsoon zone. Higher occurrence of virga rain due to subcloud evaporation and possible missing of small‐scale convective events by gauges over the dry regions are the main reasons for the observed overestimation of rain by MPEs. The decomposed components of total bias show that the major part of overestimation is due to false precipitation. The severe underestimation of rain along the west coast is attributed to the predominant occurrence of shallow rain and underestimation of moderate to heavy rain by MPEs. The decomposed components suggest that the missed precipitation and hit bias are the leading error sources for the total bias along the west coast. All evaluation metrics are found to be nearly equal in two contrasting monsoon seasons (southwest and northeast), indicating that the performance of MPEs does not change with the season, at least over southeast India. Among various MPEs, the performance of TMPA is found to be better than others, as it reproduced most of the spatial variability exhibited by the reference.
Intracellular Antibiotic Molecules
Authors: Sørensen Ole E
Published: August 2015

Phagocytes kill microbes through the action of intracellularly molecules that can be released into the phagolysosome or to the extracellular milieu. In particular, neutrophils have a vast arsenal of peptides and proteins with antimicrobial activity of importance for killing of ingested microbes. Many of these (poly)peptides act through membrane permeabilisation and subsequent lysis of bacteria, while others kill by depriving microbes of important nutrients such as iron. Furthermore, phagocytes generate short‐lived low‐molecular intermediates such as oxygen radicals and nitric oxide of great importance for the ability to kill ingested microbes. Microbes have developed elaborate strategies to circumvent exposure to intracellular antibiotic molecules by blocking cellular activation or blocking granule fusion with the phagolysosome.

Key Concepts

Phagocytes kill microbes through the action of intracellular antibiotic molecules.

Antibiotic (poly)peptides are positively charged molecules that bind to the negatively charged surface of microorganisms and kill bacteria through lysis.

Other antibiotic molecules limit bacterial growth by iron deprivation or through enzymatic activity.

Reactive oxygen derivatives such as superoxide anions and hypochlorous acid are generated by phagocytes and kill microorganisms.

Microbes have developed several strategies to circumvent killing of intracellular antibiotic molecules.
Differential Association of Psychosocial Comorbidities With Subclinical Atherosclerosis in Rheumatoid Arthritis
Authors: Liu Ying L. , Szklo Moyses , Davidson Karina W. , Bathon Joan M. , Giles Jon T.
Published: August 2015

Objective

Rheumatoid arthritis (RA) is associated with an elevated risk of cardiovascular disease (CVD) events and subclinical atherosclerosis, but the reasons for the excess risk are unclear. We explored whether psychosocial comorbidities, which may be associated with CVD in the general population, are differentially associated with subclinical atherosclerosis in RA compared to controls.

Methods

Data were from a longitudinal cohort study of 195 RA patients and 1,073 non‐RA controls. Using validated scales, heterogeneity in the associations of psychosocial measures (depression, stress, anxiety/anger, support, discrimination/hassles) with measures of subclinical atherosclerosis (coronary artery calcium [CAC] and carotid intima‐media thickness [IMT]/plaque) were compared in RA and non‐RA groups using multivariable generalized linear models. Computed tomography and ultrasound were used to identify CAC and IMT/plaque, respectively. CAC >100 units was used to define moderate/severe CAC.

Results

In RA, per‐unit higher anxiety scores (odds ratio [OR] 1.10, P = 0.029), anger scores (OR 1.14, P = 0.037), depressive symptoms (OR 3.41, P = 0.032), and caregiver stress (OR 2.86, P = 0.014) were associated with increased odds of CAC >100 units after adjustment for relevant covariates. These findings persisted despite adjustment for markers of inflammation (C‐reactive protein and interleukin‐6 levels) and were seen only in RA, not in controls (adjusted multiplicative interaction P = 0.001–0.077). In RA, job stress was associated with an increased risk of carotid plaque (adjusted OR = 3.21, P = 0.019), and increasing social support was associated with lower internal carotid IMT (adjusted P = 0.024).

Conclusion

Depressive symptoms, stress, anger/anxiety, and social support may preferentially affect CVD risk in RA, and screening/treatment for psychosocial morbidities in RA may help ameliorate the additional CVD burden.
Metal (Ni, Co)‐Metal Oxides/Graphene Nanocomposites as Multifunctional Electrocatalysts
Authors: Liu Xien , Liu Wen , Ko Minseong , Park Minjoon , Kim Min Gyu , Oh Pilgun , Chae Sujong , Park Suhyeon , Casimir Anix , Wu Gang , Cho Jaephil
Published: August 2015

Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) along with hydrogen evolution reaction (HER) have been considered critical processes for electrochemical energy conversion and storage through metal‐air battery, fuel cell, and water electrolyzer technologies. Here, a new class of multifunctional electrocatalysts consisting of dominant metallic Ni or Co with small fraction of their oxides anchored onto nitrogen‐doped reduced graphene oxide (rGO) including Co‐CoO/N‐rGO and Ni‐NiO/N‐rGO are prepared via a pyrolysis of graphene oxide and cobalt or nickel salts. Ni‐NiO/N‐rGO shows the higher electrocatalytic activity for the OER in 0.1 m KOH with a low overpotential of 0.24 V at a current density of 10 mA cm−2, which is superior to that of the commercial IrO2. In addition, it exhibits remarkable activity for the HER, demonstrating a low overpotential of 0.16 V at a current density of 20 mA cm−2 in 1.0 m KOH. Apart from similar HER activity to the Ni‐based catalyst, Co‐CoO/N‐rGO displays the higher activity for the ORR, comparable to Pt/C in zinc‐air batteries. This work provides a new avenue for the development of multifunctional electrocatalysts with optimal catalytic activity by varying transition metals (Ni or Co) for these highly demanded electrochemical energy technologies.
Combination Growth Factor Therapy via Electrostatically Assembled Wound Dressings Improves Diabetic Ulcer Healing In Vivo
Authors: Almquist Benjamin D. , Castleberry Steven A. , Sun Julia B. , Lu Alice Y. , Hammond Paula T.
Published: August 2015

Chronic skin ulcerations are a common complication of diabetes mellitus, affecting up to one in four diabetic individuals. Despite the prevalence of these wounds, current pharmacologic options for treating them remain limited. Growth factor–based therapies have displayed a mixed ability to drive successful healing, which may be due to nonoptimal delivery strategies. Here, a method for coating commercially available nylon dressings using the layer‐by‐layer process is described to enable both sustained release and independent control over the release kinetics of vascular endothelial growth factor 165 and platelet‐derived growth factor BB. It is shown that the use of strategically spaced diffusion barriers formed spontaneously by disulfide bonds enables independent control over the release rates of incorporated growth factors, and that in vivo these dressings improve several aspects of wound healing in db/db mice.
Nanostructured Ion‐Exchange Membranes for Fuel Cells: Recent Advances and Perspectives
Authors: He Guangwei , Li Zhen , Zhao Jing , Wang Shaofei , Wu Hong , Guiver Michael D. , Jiang Zhongyi
Published: August 2015

Polymer‐based materials with tunable nanoscale structures and associated microenvironments hold great promise as next‐generation ion‐exchange membranes (IEMs) for acid or alkaline fuel cells. Understanding the relationships between nanostructure, physical and chemical microenvironment, and ion‐transport properties are critical to the rational design and development of IEMs. These matters are addressed here by discussing representative and important advances since 2011, with particular emphasis on aromatic‐polymer‐based nanostructured IEMs, which are broadly divided into nanostructured polymer membranes and nanostructured polymer–filler composite membranes. For each category of membrane, the core factors that influence the physical and chemical microenvironments of the ion nanochannels are summarized. In addition, a brief perspective on the possible future directions of nanostructured IEMs is presented.
Engineering design of outer‐selective tribore hollow fiber membranes for forward osmosis and oil‐water separation
Authors: Li Xue , Ang Wan Lin , Liu Yingda , Chung Tai‐Shung
Published: August 2015

Outer‐selective thin‐film composite (TFC) hollow fiber membranes offer advantages like less fiber blockage in the feed stream and high packing density for industrial applications. However, outer‐selective TFC hollow fiber membranes are rarely commercially available due to the lack of effective ways to remove residual reactants from fiber's outer surface during interfacial polymerization and form a defect‐free polyamide film. A new simplified method to fabricate outer‐selective TFC membranes on tribore hollow fiber substrates is reported. Mechanically robust tribore hollow fiber substrates containing three circular‐sector channels were first prepared by spinning a P84/ethylene glycol mixed dope solution with delayed demixing at the fiber lumen. The thin wall tribore hollow fibers have a large pure water permeability up to 300 L m−2 h−1 bar−1. Outer‐selective TFC tribore hollow fiber membranes were then fabricated by interfacial polymerization with the aid of vacuum sucking to ensure the TFC layer well‐attached to the substrate. Under forward osmosis studies, the TFC tribore hollow fiber membrane exhibits a good water flux and a small flux difference between active‐to‐draw (i.e., the active layer facing the draw solution) and active‐to‐feed (i.e., the active layer facing the feed solution) modes due to the small internal concentration polarization. A hyperbranched polyglycerol was further grafted on top of the newly developed TFC tribore hollow fiber membranes for oily wastewater treatment. The membrane displays low fouling propensity and can fully recover its water flux after a simple 20‐min water wash at 0.5 bar from its lumen side, which makes the membrane preferentially suitable for oil‐water separation. © 2015 American Institute of Chemical Engineers AIChE J, 61: 4491–4501, 2015
Role of radiation therapy in primary mediastinal large B‐cell lymphoma in rituximab era: A US population‐based analysis
Authors: Giri Smith , Bhatt Vijaya Raj , Pathak Ranjan , Bociek R. Gregory , Vose Julie M. , Armitage James O.
Published: August 2015

The use of radiation (RT) in primary mediastinal large B‐cell lymphoma (PMBCL) may predispose young patients to the risk of cardiopulmonary toxicities and secondary malignancies. We used Surveillance, Epidemiology and End Results (SEER) 18 database to compare the overall survival (OS) differences among adult patients treated with and without RT after rituximab approval in the US. Multivariate analyses were performed using Cox proportional hazards regression to compare OS based on the use of RT while adjusting for age, year of diagnosis, race, stage and gender. PMBCL patients (n = 258), who received RT (48%), were similar in terms of age, gender, race, and stage at diagnosis to patients who did not receive RT. The five year OS was similar between patients treated with versus without RT (82.5% vs. 78.6%, P = 0.47). In a multivariate analysis, the use of RT did not influence OS in the rituximab era (HR 0.83; 95% CI 0.43–1.59; P = 0.56). Rituximab may reduce the benefit of RT in select patients such as those who achieve a metabolic complete remission at the end of chemotherapy. Am. J. Hematol. 90:1052–1054, 2015. © 2015 Wiley Periodicals, Inc.
Super‐resolution microscopy by movable thin‐films with embedded microspheres: Resolution analysis
Authors: Allen Kenneth W. , Farahi Navid , Li Yangcheng , Limberopoulos Nicholaos I. , Walker Dennis E. , Urbas Augustine M. , Liberman Vladimir , Astratov Vasily N.
Published: August 2015

Microsphere‐assisted imaging has emerged as an extraordinary simple technique of obtaining optical super‐resolution. This work addresses two central problems in developing this technology: i) methodology of the resolution measurements and ii) limited field‐of‐view provided by each sphere. It is suggested that a standard method of resolution analysis in far‐field microscopy based on convolution with the point‐spread function can be extended into the super‐resolution area. This allows developing a unified approach to resolution measurements, which can be used for comparing results obtained by different techniques. To develop the surface scanning functionality, the high‐index (n ∼ 2) barium titanate glass microspheres were embedded in polydimethylsiloxane (PDMS) thin‐films. It is shown that such films adhere to the surface of nanoplasmonic structures so that the tips of embedded spheres experience the objects’ optical near‐fields. Based on rigorous criteria, the resolution ∼λ/6‐λ/7 (where λ is the illumination wavelength) is demonstrated for arrays of Au dimers and bowties. Such films can be translated along the surface of investigated samples after liquid lubrication. It is shown that just after lubrication the resolution is diffraction limited, however the super‐resolution gradually recovers as the lubricant evaporates.

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Six‐Coordinate Group 13 Complexes: The Role of d Orbitals and Electron‐Rich Multi‐Center Bonding
Authors: Goesten Maarten G. , Fonseca Guerra Célia , Kapteijn Freek , Gascon Jorge , Bickelhaupt F. Matthias
Published: August 2015

Bonding in six‐coordinate complexes based on Group 13 elements (B, Al, Ga, In, Tl) is usually considered to be identical to that in transition‐metal analogues. We herein demonstrate through sophisticated electronic‐structure analyses that the bonding in these Group 13 element complexes is fundamentally different and better characterized as electron‐rich hypervalent bonding with essentially no role for the d orbitals. This characteristic is carried through to the molecular properties of the complex.
Self‐Assembly and Disassembly of Vesicles as Controlled by Anion–π Interactions
Authors: He Qing , Ao Yu‐Fei , Huang Zhi‐Tang , Wang De‐Xian
Published: August 2015

Anion–π interactions have been widely studied as new noncovalent driving forces in supramolecular chemistry. However, self‐assembly induced by anion–π interactions is still largely unexplored. Herein we report the formation of supramolecular amphiphiles through anion–π interactions, and the subsequent formation of self‐assembled vesicles in water. With the π receptor 1 as the host and anionic amphiphiles, such as sodium dodecylsulfate (SDS), sodium laurate (SLA), and sodium methyl dodecylphosphonate (SDP), as guests, the sequential formation of host–guest supramolecular amphiphiles and self‐assembled vesicles was demonstrated by SEM, TEM, DLS, and XRD techniques. The intrinsic anion–π interactions between 1 and the anionic amphiphiles were confirmed by crystal diffraction, HRMS analysis, and DFT calculations. Furthermore, the controlled disassembly of the vesicles was promoted by competing anions, such as NO3−, Cl−, and Br−, or by changing the pH value of the medium.
The effect of high temperature annealing process on crystallization process of polypropylene, mechanical properties, and surface quality of plastic parts
Authors: Wang Weihua , Zhao Guoqun , Wu Xianghong , Zhai Zhen
Published: August 2015

This work studied the effects and action mechanism of high‐temperature annealing process parameters, such as annealing temperature, annealing duration and cooling speed, on the microstructural evolution of polypropylene (PP) on different thickness layers, the surface quality, and mechanical properties of PP plastic parts. The results show that when the PP plastic parts are annealed at slightly higher than 100°C, the resin on the surface and internal layers of plastic parts just generates the relaxation and rearrangement at the molecular level. Only at an enough high annealing temperature, the secondary crystallization and phase transformation process can be observed. The crystallinity of all annealed samples is higher than that of unannealed samples, but the crystallinity is decreased with the increase of cooling speed after annealing duration, and the annealing duration exceeding 60 min almost has no effect on the crystallinity. The microstructural change of PP on the internal layer of plastic parts is weaker than that on the surface layer. The surface hardness of the plastic parts mainly depends on the crystallinity of the surface layer, whereas the surface roughness of the plastic parts depends on not only the crystallinity, but also the space conformation of molecular chains and the residual stress. With the change of annealing process parameters, the tensile and impact strengths of plastic parts show a non‐monotonic change law. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42773.
Effects of the short‐fiber tip geometry and interphase properties on the interfacial debonding behavior of rubber matrix composites
Authors: Yu Xiaoming , Gu Boqin , Zhang Bin
Published: August 2015

An axisymmetric finite element model of a single fiber embedded in a rubber matrix was established. A cohesive zone model was used for the fiber–matrix interface because of the interfacial failure. The effect of the fiber tip shape on the interfacial debonding of short‐fiber‐reinforced rubber matrix sealing composites (SFRCs) was investigated; the shapes were flat, semi‐elliptical, hemispherical, and conoid, respectively. The initial strain of the interfacial debonding (ε0) was obtained. We found that among the researched fiber tips, ε0 of the SFRC reinforced with the hemispherical tip fiber appeared to be the maximum. The initial locations of interfacial debonding were also determined. The results show that the initial locations of the interfacial debonding moved from the edge to the center of the fiber tip when the ratio of the semimajor axis and semiminor axis of the semi‐elliptical fiber tip increased gradually. Further study on the effect of the interphase properties on ε0 with the hemispherical fiber tip was conducted. The results indicate that an interphase thickness of 0.2 μm and an interphase elastic modulus of about 752 MPa were optimal for restraining the initiation of the interfacial debonding. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42774.
Polyaniline/silver/cerium nitrate ternary composite: Synthesis, characterization and enhanced electrochemical properties
Authors: Li Yanbo , Li Zhihua , Zheng Feng
Published: August 2015

Polyaniline/Ag/Ce (NO3)3 ternary composites were prepared by in situ polymerization in a poly (2‐arcylamido‐2‐methylpropane sulfonic acid) aqueous solution. Fourier transform infrared spectroscopy and Ultraviolet‐visible spectroscopy analyses indicated that Ce ions had a conjugated interaction with N, O of polyaniline (PANI), and poly (2‐arcylamido‐2‐methylpropane sulfonic acid). By comparison with PANI and PANI binary composite, this ternary composite had a better thermal stability, a high conductivity (3.49 S/cm), a large capacitance, and a high electrochemical activity. Especially, the corrosion potential of this ternary composite can reach −418 mV and the inhibition efficiency can be increased by 68.08%. This ternary porous composite has promising applications in capacitor, conductive materials, anticorrosion coating, and other related fields. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42785.
Dielectric property, electric breakdown, and discharged energy density of a poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) copolymer with low temperature processing
Authors: Xia Weimin , Liang Fan , Xing Junhong , Xu Zhuo
Published: August 2015

Different thermal processing methods were used to fabricate the crystalline properties of poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) [P(VDF‐co‐CTFE)] films. We observed that the crystallinity and crystal grain size of the various samples decreased with the quenching temperature. Compared to that of the annealed P(VDF‐co‐CTFE) sample, a higher dielectric constant of 13.9 at a frequency of 100 Hz was obtained in the film with liquid nitrogen quenching because the increasing small crystalline regions were susceptible to the excitation of external electric field. Meanwhile, the breakdown electric strength of the low‐temperature‐quenched film increased to 530 MV/m when the depth of shallow electronic energy level decreased, as depicted by Fröhlich collective electron approximated electric breakdown theory. Moreover, when we introduced the leakage current density curves, the effect of the space charges on the electric displacement was proven. As a result, the discharged energy density of the liquid‐nitrogen‐quenched P(VDF‐co‐CTFE) film was enhanced to 15.32 J/cm3 at an electric field of 530 MV/m; this provided an effective way in addition to chemical modification to achieve a high energy storage ability in this poly(vinylidene fluoride)‐based fluoropolymer. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42794.
Review conformation, self‐aggregation, and membrane interaction of peptaibols as studied by pulsed electron double resonance spectroscopy
Authors: Milov Alexander D. , Tsvetkov Yuri D. , Raap Jan , De Zotti Marta , Formaggio Fernando , Toniolo Claudio
Published: August 2015

Pulsed EPR methods, in particular pulsed electron double resonance (PELDOR) [or double electron–electron resonance (DEER)], are very sensitive to the dipole ··· dipole interaction between electron spins in a pair of free radicals. Using PELDOR, the conformations of a number of double radical‐containing biomolecules have been determined. In this review article, we focused our attention on the application of this spectroscopy to nitroxide‐labeled peptaibols. This is an emerging class of naturally occurring, relatively short, linear, helical peptide molecules endowed with hydrophobic character, capability to interact with and to alter the structure of membranes, and antibiotic activity. We extracted detailed information on the secondary structures of specifically site‐directed, double nitroxide‐labeled peptaibols under a variety of experimental conditions, including biologically relevant environments. Moreover, we examined in‐depth peptaibol clustering, related to the marked propensity of these molecules to undergo self‐association in model and whole‐cell membrane systems, using mainly mono‐nitroxide‐containing synthetic analogs. Finally, based on the PELDOR data accumulated, we proposed models of supramolecular (quaternary) structures of peptaibols and their binding modes to membranes. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 6–24, 2016.
Challenges of extraordinary experiences in the Arctic
Authors: Lindberg Frank , Eide Dorthe
Published: August 2015

This paper presents and discusses findings from extraordinary experiences in the Arctic Svalbard. Although extensive consumer research has focused on the positive, sublime, and communal aspects of extraordinary experiences, little emphasis has been placed on the challenging aspects. By focusing on Arctic horse riding, Arctic adventure travel and dog sledding from a practice perspective, this study provides evidence that extraordinary consumption can be marked by challenges because of unrealistic expectations, troubling learning practices and connecting with others, and how one copes with tensions. We discuss how these four main types of challenges mark consumption and as such provide a nuanced interpretation compared with the positive connotations of previous research. Copyright © 2015 John Wiley & Sons, Ltd.
Radial artery occlusion and hand strength after percutaneous coronary procedures: Results of the HANGAR study
Authors: Sciahbasi Alessandro , Rigattieri Stefano , Sarandrea Alessandro , Cera Maria , Di Russo Cristian , Fedele Silvio , Romano Silvio , Penco Maria , Rocco Pugliese Francesco
Published: August 2015

Objectives: The aim of this prospective study was to evaluate muscle force of the hand, thumb, and forefinger in patients with prolonged radial occlusion after transradial percutaneous coronary procedures. Background: There are no data on hand strength and function in patients with prolonged radial occlusion after percutaneous coronary procedures. Methods: Elective patients with chronic stable angina undergoing percutaneous coronary procedures were evaluated the day before the procedure for radial artery patency, Allen test, hand grip, and thumb and forefinger pinch tests. The same measures were performed the day after the procedure and at follow‐up. At follow‐up, patients were divided in two groups according to the radial patency (group 1) or occlusion (group 2). Results: Of the 99 patients included in the study, 90 patients had a patent radial artery (group 1), and nine (9.1%) patients had an occluded artery (group 2). At baseline, there were no significant differences in hand grip test between the two groups (42 ± 11 kg in group 1 and 41 ± 17 kg in group 2, P = 0.74). In both groups, after the procedure, the hand grip test values was significantly reduced compared with baseline values (40 ± 11 kg in group 1, P < 0.0001 and 37 ± 17 kg in group 2, P = 0.007). Finally, at follow‐up, in both groups, the hand grip test values returned to baseline values. Thumb and forefinger pinch tests did not show significant differences after the procedure and at follow‐up, compared with baseline. Conclusions: Radial artery occlusion after percutaneous coronary procedures was not associated with a reduction in hand and finger strength. © 2015 Wiley Periodicals, Inc.
ChemInform Abstract: The Chemistry and Bioactivity of Southern African Flora II: Flavonoids, Quinones and Minor Compound Classes
Authors: Babiaka Smith B. , Ntie‐Kang Fidele , Ndingkokhar Bakoh , Mbah James A. , Sippl Wolfgang , Yong Joseph N.
Published: August 2015

Review: 134 refs + subrefs.
Influence of Temperature on the Formation of Silver Nanoparticles by using a Seed‐Free Photochemical Method under Sodium‐Lamp Irradiation
Authors: Kuo Yen‐Ling , Juang Tzong‐Yuan , Chang Shi‐Hise , Tsai Chin‐Ming , Lai Yen‐Shang , Yang Li‐Chen , Huang Cheng‐Liang
Published: August 2015

Silver nanoparticles can be prepared by using a seed‐free photo‐assisted citrate reduction method under the irradiation of a sodium lamp. Under the same irradiation intensity, bath temperatures are crucial in influencing the reaction rate, morphologies of final products, and shape evolution of the silver nanostructures. For example, when the bath temperature is 80 °C, the product yields of silver nanoplates, nanorods, and nanodecahedra are 38±6 %, 35±10 %, and 12±8 %, respectively. However, when the bath temperature is 30 °C, the product yields of silver nanoplates, nanorods, and nanodecahedra are 6±3 %, 0 %, and 83±16 %, respectively. Time‐dependent UV/Vis spectra and TEM images show that silver nanoplates were formed at the earlier reaction stage and greatly decreased in amount at the later stage when the bath temperatures are less than or equal to 40 °C. This indicates that the silver nanoplates, which can be regarded as intermediates, are kinetically favored products. They are not thermodynamically favored products at these relatively low bath temperatures. The SERS spectra of crystal violet (CV) show that all the silver colloids synthesized at various temperatures exhibit good enhancement factors and that the colloids prepared at lower bath temperatures have a higher enhancement factor.