bluuebunny/crossref_metadata_2025 huggingface dataset:
Metals and metalloids in precipitation collected during CHINARE campaign from Shanghai, China, to Zhongshan Station, Antarctica: Spatial variability and source identification
Authors: Shi G. , Teng J. , Ma H. , Li Y. , Sun B.
Published: May 2015

Metals and metalloids in continental precipitation have been widely observed, but the data over open oceans are still very limited. Investigation of metals and metalloids in marine precipitation is of great significance to understand global transport of these elements in the atmosphere and their input fluxes to the oceans. So shipboard sampling of precipitation was conducted during a Chinese National Antarctic Research Expedition campaign from Shanghai, China, to Zhongshan Station, East Antarctica, and 22 samples (including 17 rainfall and 5 snowfall events) were collected and analyzed for concentrations of Pb, Ni, Cr, Cu, Co, Hg, As, Cd, Sb, Se, Zn, Mn, and Ti. Results show that concentrations of both metals and metalloids vary considerably along the cruise, with higher concentrations at coastal sites and lower values on the south Indian Ocean. Although only soluble fractions were determined for elements, concentrations in this study are generally comparable to the reported values of marine rain. Enrichment factor analysis shows that most of metals and metalloids are enriched versus crustal sources, even in the samples collected from remote south Indian Ocean. In addition, metals and metalloids in precipitation are also very enriched above sea‐salt abundance, indicating that impacts of sea‐salt aerosols on their concentrations are negligible. Main sources of metals and metalloids were explored with the aid of multivariate statistical analyses. The results show that human emissions have far‐reaching distribution, which may exert an important influence on the solubility of elements in precipitation. This investigation provides valuable information on spatial variation and possible sources of trace elements in precipitation over the open oceans corresponding to understudied region.
RACORO continental boundary layer cloud investigations: 2. Large‐eddy simulations of cumulus clouds and evaluation with in situ and ground‐based observations
Authors: Endo Satoshi , Fridlind Ann M. , Lin Wuyin , Vogelmann Andrew M. , Toto Tami , Ackerman Andrew S. , McFarquhar Greg M. , Jackson Robert C. , Jonsson Haflidi H. , Liu Yangang
Published: May 2015

A 60 h case study of continental boundary layer cumulus clouds is examined using two large‐eddy simulation (LES) models. The case is based on observations obtained during the RACORO Campaign (Routine Atmospheric Radiation Measurement (ARM) Aerial Facility (AAF) Clouds with Low Optical Water Depths (CLOWD) Optical Radiative Observations) at the ARM Climate Research Facility's Southern Great Plains site. The LES models are driven by continuous large‐scale and surface forcings and are constrained by multimodal and temporally varying aerosol number size distribution profiles derived from aircraft observations. We compare simulated cloud macrophysical and microphysical properties with ground‐based remote sensing and aircraft observations. The LES simulations capture the observed transitions of the evolving cumulus‐topped boundary layers during the three daytime periods and generally reproduce variations of droplet number concentration with liquid water content (LWC), corresponding to the gradient between the cloud centers and cloud edges at given heights. The observed LWC values fall within the range of simulated values; the observed droplet number concentrations are commonly higher than simulated, but differences remain on par with potential estimation errors in the aircraft measurements. Sensitivity studies examine the influences of bin microphysics versus bulk microphysics, aerosol advection, supersaturation treatment, and aerosol hygroscopicity. Simulated macrophysical cloud properties are found to be insensitive in this nonprecipitating case, but microphysical properties are especially sensitive to bulk microphysics supersaturation treatment and aerosol hygroscopicity.
Hydraulics of floods upstream of horseshoe canyons and waterfalls
Authors: Lapotre Mathieu G. A. , Lamb Michael P.
Published: May 2015

Horseshoe waterfalls are ubiquitous in natural streams, bedrock canyons, and engineering structures. Nevertheless, water flow patterns upstream of horseshoe waterfalls are poorly known and likely differ from the better studied case of a one‐dimensional linear step because of flow focusing into the horseshoe. This is a significant knowledge gap because the hydraulics at waterfalls controls sediment transport and bedrock incision, which can compromise the integrity of engineered structures and influence the evolution of river canyons on Earth and Mars. Here we develop new semiempirical theory for the spatial acceleration of water upstream of, and the cumulative discharge into, horseshoe canyons and waterfalls. To this end, we performed 110 numerical experiments by solving the 2‐D depth‐averaged shallow‐water equations for a wide range of flood depths, widths and discharges, and canyon lengths, widths and bed gradients. We show that the upstream, normal flow Froude number is the dominant control on lateral flow focusing and acceleration into the canyon head and that focusing is limited when the flood width is small compared to a cross‐stream backwater length scale. In addition, for sheet floods much wider than the canyon, flow focusing into the canyon head leads to reduced discharge (and drying in cases) across the canyon sidewalls, which is especially pronounced for canyons that are much longer than they are wide. Our results provide new expectations for morphodynamic feedbacks between floods and topography, and thus canyon formation.
Methane oxidation in the eastern tropical North Pacific Ocean water column
Authors: Pack Mary A. , Heintz Monica B. , Reeburgh William S. , Trumbore Susan E. , Valentine David L. , Xu Xiaomei , Druffel Ellen R. M.
Published: May 2015

We report methane (CH4) concentration and methane oxidation (MOx) rate measurements from the eastern tropical north Pacific (ETNP) water column. This region comprises low‐CH4 waters and a depth interval (~200–760 m) of CH4 supersaturation that is located within a regional oxygen minimum zone (OMZ). MOx rate measurements were made in parallel using tracer‐based methods with low‐level 14C‐CH4 (LL 14C) and 3H‐CH4 (3H). The two tracers showed similar trends in MOx rate with water depth, but consistent with previous work, the LL 14C rates (range: 0.034–15 × 10−3 nmol CH4 L−1 d−1) were systematically slower than the parallel 3H rates (range: 0.098–4000 × 10−3 nmol CH4 L−1 d−1). Priming and background effects associated with the 3H‐CH4 tracer and LL 14C filtering effects are implicated as the cause of the systematic difference. The MOx rates reported here include some of the slowest rates measured in the ocean to date, are the first rates for the ETNP region, and show zones of slow CH4 turnover within the OMZ that may permit CH4 derived from coastal sediments to travel great lateral distances. The MOx rate constants correlate with both CH4 and oxygen concentrations, suggesting that their combined availability regulates MOx rates in the region. Depth‐integrated MOx rates provide an upper limit on the magnitude of regional CH4 sources and demonstrate the importance of water column MOx, even at slow rates, as a sink for CH4 that limits the ocean‐atmosphere CH4 flux in the ETNP region.
Stationary‐phase integrals in the cross correlation of ambient noise
Authors: Boschi Lapo , Weemstra Cornelis
Published: May 2015

The cross correlation of ambient signal allows seismologists to collect data even in the absence of seismic events. “Seismic interferometry” shows that the cross correlation of simultaneous recordings of a random wavefield made at two locations is formally related to the impulse response between those locations. This idea has found many applications in seismology, as a growing number of dense seismic networks become available: cross‐correlating long seismic records, the Green's function between instrument pairs is “reconstructed” and used, just like the seismic recording of an explosion, in tomography, monitoring, etc. These applications have been accompanied by theoretical investigations of the relationship between noise cross correlation and the Green's function; numerous formulations of “ambient noise” theory have emerged, each based on different hypotheses and/or analytical approaches. The purpose of this study is to present most of those approaches together, providing a comprehensive overview of the theory. Understanding the specific hypotheses behind each Green's function recipe is critical to its correct application. Hoping to guide nonspecialists who approach ambient noise theory for the first time, we treat the simplest formulation (the stationary‐phase approximation applied to smooth unbounded media) in detail. We then move on to more general treatments, illustrating that the “stationary‐phase” and “reciprocity theorem” approaches lead to the same formulae when applied to the same scenario. We show that a formal cross correlation/Green's function relationship can be found in complex, bounded media and for nonuniform source distributions. We finally provide the bases for understanding how the Green's function is reconstructed in the presence of scattering obstacles.
Soil surface organic layers in Arctic Alaska: Spatial distribution, rates of formation, and microclimatic effects
Authors: Baughman Carson A. , Mann Daniel H. , Verbyla David L. , Kunz Michael L.
Published: May 2015

Organic layers of living and dead vegetation cover the ground surface in many permafrost landscapes and play important roles in ecosystem processes. These soil surface organic layers (SSOLs) store large amounts of carbon and buffer the underlying permafrost and its contained carbon from changes in aboveground climate. Understanding the dynamics of SSOLs is a prerequisite for predicting how permafrost and carbon stocks will respond to warming climate. Here we ask three questions about SSOLs in a representative area of the Arctic Foothills region of northern Alaska: (1) What environmental factors control the thickness of SSOLs and the carbon they store? (2) How long do SSOLs take to develop on newly stabilized point bars? (3) How do SSOLs affect temperature in the underlying ground? Results show that SSOL thickness and distribution correlate with elevation, drainage area, vegetation productivity, and incoming solar radiation. A multiple regression model based on these correlations can simulate spatial distribution of SSOLs and estimate the organic carbon stored there. SSOLs develop within a few decades after a new, sandy, geomorphic surface stabilizes but require 500–700 years to reach steady state thickness. Mature SSOLs lower the growing season temperature and mean annual temperature of the underlying mineral soil by 8 and 3°C, respectively. We suggest that the proximate effects of warming climate on permafrost landscapes now covered by SSOLs will occur indirectly via climate's effects on the frequency, extent, and severity of disturbances like fires and landslides that disrupt the SSOLs and interfere with their protection of the underlying permafrost.
ADAMTSL4‐associated isolated ectopia lentis: Further patients, novel mutations and a detailed phenotype description
Authors: Neuhann Teresa M. , Stegerer Annette , Riess Angelika , Blair Edward , Martin Thomas , Wieser Stefanie , Kläs Rüdiger , Bouman Arjan , Kuechler Alma , Rittinger Olaf
Published: May 2015

ADAMTSL4 mutations seem to be the most common cause of isolated ectoplia lentis (EL) and thus are important concerning the differential diagnosis of connective tissue syndromes with EL as main feature. In this study, we describe an additional cohort of patients with apparently isolated EL. All underwent a detailed clinical exam with cardiac evaluation combined with ADAMTSL4 mutation analysis. Mutations were identified in 12/15 patients with EL. Besides the European founder mutation p. (Gln256Profs*38) we identified five further mutations not yet described in the literature: p. (Leu249Tyrfs*21), p. (Ala388Glyfs*8), p. (Arg746His), p. (Gly592Ser), and p. (Arg865His). Clinical evaluation showed common additional ocular features such as high myopia, but no major systemic findings. In particular: no dilatation of the aortic root was reported on. This report increases the total number of patients with ADAMTSL4 mutations reported on today and reviews in detail the clinical findings in all patients reported on to date demonstrate, that these patients have a mainly ocular phenotype. There are no consistent systemic findings. The differentiation between syndromic and isolated EL is crucial for the further surveillance, treatment, and counseling of these patients, especially in young children. © 2015 Wiley Periodicals, Inc.
Word and text processing in acquired prosopagnosia
Authors: Hills Charlotte S. , Pancaroglu Raika , Duchaine Brad , Barton Jason J. S.
Published: May 2015

Objective

A novel hypothesis of object recognition asserts that multiple regions are engaged in processing an object type, and that cerebral regions participate in processing multiple types of objects. In particular, for high‐level expert processing, it proposes shared rather than dedicated resources for word and face perception, and predicts that prosopagnosic subjects would have minor deficits in visual word processing, and alexic subjects would have subtle impairments in face perception. In this study, we evaluated whether prosopagnosic subjects had deficits in processing either the word content or the style of visual text.

Methods

Eleven prosopagnosic subjects, 6 with unilateral right lesions and 5 with bilateral lesions, participated. In the first study, we evaluated their word length effect in reading single words. In the second study, we assessed their time and accuracy for sorting text by word content independent of style, and for sorting text by handwriting or font style independent of word content.

Results

Only subjects with bilateral lesions showed mildly elevated word length effects. Subjects were not slowed in sorting text by word content, but were nearly uniformly impaired in accuracy for sorting text by style.

Interpretation

Our results show that prosopagnosic subjects are impaired not only in face recognition but also in perceiving stylistic aspects of text. This supports a modified version of the many‐to‐many hypothesis that incorporates hemispheric specialization for processing different aspects of visual text. Ann Neurol 2015;78:258–271
A Bioorthogonal Chemical Reporter of Viral Infection
Authors: Neef Anne B. , Pernot Lucile , Schreier Verena N. , Scapozza Leonardo , Luedtke Nathan W.
Published: May 2015

Pathogen‐selective labeling was achieved by using the novel gemcitabine metabolite analogue 2′‐deoxy‐2′,2′‐difluoro‐5‐ethynyluridine (dF‐EdU) and click chemistry. Cells infected with Herpes Simplex Virus‐1 (HSV‐1), but not uninfected cells, exhibit nuclear staining upon the addition of dF‐EdU and a fluorescent azide. The incorporation of the dF‐EdU into DNA depends on its phosphorylation by a herpes virus thymidine kinase (TK). Crystallographic analyses revealed how dF‐EdU is well accommodated in the active site of HSV‐1 TK, but steric clashes prevent dF‐EdU from binding human TK. These results provide the first example of pathogen‐enzyme‐dependent incorporation and labeling of bioorthogonal functional groups in human cells.
Graphitic‐Carbon Layers on Oxides: Toward Stable Heterogeneous Catalysts for Biomass Conversion Reactions
Authors: Xiong Haifeng , Schwartz Thomas J. , Andersen Nalin I. , Dumesic James A. , Datye Abhaya K.
Published: May 2015

Conversion of biomass‐derived molecules involves catalytic reactions under harsh conditions in the liquid phase (e.g., temperatures of 250 °C and possibly under either acidic or basic conditions). Conventional oxide‐supported catalysts undergo pore structure collapse and surface area reduction leading to deactivation under these conditions. Here we demonstrate an approach to deposit graphitic carbon to protect the oxide surface. The heterogeneous catalysts supported on the graphitic carbon/oxide composite exhibit excellent stability (even under acidic conditions) for biomass conversion reactions.
Praktische kontinuierliche Durchfluss‐Abfangmetallierungen funktionalisierter Arene und Heteroarene mit TMPLi in Gegenwart von Mg‐, Zn‐, Cu‐ oder La‐Halogeniden
Authors: Becker Matthias R. , Knochel Paul
Published: May 2015

Es wird die Durchflussmetallierung verschiedener Arene und Heteroarene durch In‐situ‐Abfangen mit Metallsalzen (ZnCl2⋅2 LiCl, MgCl2, CuCN⋅2 LiCl, LaCl3⋅2 LiCl) unter sehr zweckmäßigen Bedingungen (0 °C, 40 s) beschrieben. Die entstehenden Mg‐, Zn‐, Cu‐ oder La‐organischen Spezies werden mit verschiedenen Elektrophilen in hohen Ausbeuten abgefangen. In mehreren Fällen werden ungewöhnliche kinetische Regioselektivitäten erzielt. Die Durchflussmetallierungen werden ohne weitere Optimierung schlicht durch Verlängerung der Reaktionszeit skaliert. Verglichen mit den entsprechenden Batch‐Prozessen werden die Anwendungsmöglichkeiten durch solche Flussmetallierungen beträchtlich erweitert.
A Minimal β‐Lactone Fragment for Selective β5c or β5i Proteasome Inhibitors
Authors: Groll Michael , Korotkov Vadim S. , Huber Eva M. , de Meijere Armin , Ludwig Antje
Published: May 2015

Broad‐spectrum proteasome inhibitors are applied as anticancer drugs, whereas selective blockage of the immunoproteasome represents a promising therapeutic rationale for autoimmune diseases. We here aimed at identifying minimal structural elements that confer β5c or β5i selectivity on proteasome inhibitors. Based on the natural product belactosin C, we synthesized two β‐lactones featuring a dimethoxybenzyl moiety and either a methylpropyl (pseudo‐isoleucin) or an isopropyl (pseudo‐valine) P1 side chain. Although the two compounds differ only by one methyl group, the isoleucine analogue is six times more potent for β5i (IC50=14 nM) than the valine counterpart. Cell culture experiments demonstrate the cell‐permeability of the compounds and X‐ray crystallography data highlight them as minimal fragments that occupy primed and non‐primed pockets of the active sites of the proteasome. Together, these results qualify β‐lactones as a promising lead‐structure motif for potent nonpeptidic proteasome inhibitors with diverse pharmaceutical applications.
In Situ Microscopic Observation of the Crystallization Process of Molecular Microparticles by Fluorescence Switching
Authors: Ye Xin , Liu Yang , Lv Yun , Liu Guangfeng , Zheng Xiaoxin , Han Quanxiang , Jackson Kenneth A. , Tao Xutang
Published: May 2015

To clearly understand the solid‐state amorphous‐to‐crystalline transformation is a long‐standing challenge because such crystallization occuring in confined environments is difficult to observe directly. We developed an in situ and real‐time imaging procedure to record the interface evolution in a solid‐state crystallization of molecular amorphous particles. The method, by employing a tetra‐substituted ethene with novel morphology‐dependent fluorescence, which can distinguish the interfaces between the crystalline and amorphous phase by fluorescence color, is a simple and practical method to probe the inner process of a molecular microparticle. The crystallization of amorphous microparticles in different cases was clearly recorded, where the perfect microparticles and those with defects demonstrate diverse destinies. The details disclosed in this observation will deepen the understanding for a series of solid‐state crystallization that we know little about before.
Crystallization behavior and mechanical properties of an electrospun ethanol‐mediated poly(ethylene terephthalate) fibrous membrane
Authors: Wang Li‐Na , Wang Yan‐Wei , Liu Wen‐Tao , Xia Xue‐Lian , He Su‐Qin , Liu Hao , Zhu Cheng‐Shen
Published: May 2015

A simple approach for preparing electrospun poly(ethylene terephthalate) (PET) fibrous membranes with excellent spinnability and mechanical properties is introduced in this article. To enhance the electrospinnability of PET, a small content of ethanol was incorporated into a 16 wt % PET solution. The effects of ethanol on the solution properties, mechanical properties and crystallization properties and the related morphology were systematically evaluated. The conductivity (κ) measurement indicated that ethanol could obviously improve κ of the PET solution; this correlated well with the morphology of fibers. Scanning electron microscopy images showed that the diameter of the fibers decreased with increasing solution κ. The tensile strength of the PET fibrous membrane increased 1.8 times through the blending of 2.5 vol % ethanol with the PET solution. The differential scanning calorimetry results showed that the crystallinity was improved when the ethanol content increased; this was beneficial to the enhancement of the tensile strength. The glass‐transition temperature and melting temperature increased slightly, but the cold‐crystallization peak shifted to a lower temperature with increasing ethanol content (<3.75 vol %); this was attributed to the increasing in the oriented degree. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42341.
Physical properties and crystallization behavior of poly(lactide)/poly(methyl methacrylate)/silica composites
Authors: Wu Jyh‐Horng , Kuo M. C. , Chen Chien‐Wen
Published: May 2015

Poly(lactide)/poly(methyl methacrylate)/silica (PLA/PMMA/SiO2) composites were fabricated using a twin‐screw extruder. Nanosilica particles were incorporated to improve the toughness of the brittle PLA, and a chain extender reagent (Joncryl ADR 4368S) was used to reduce the hydrolysis of the PLA during fabrication. Highly transparent PLA and PMMA were designated to blend to obtain the miscible and transparent blends. To estimate the performance of the PLA/PMMA/SiO2 composites, a series of measurements was conducted, including tensile and Izod impact tests, light transmission and haze measurements, thermomechanical analysis, and isothermal crystallization behavior determination. A chain extender increases the ultimate tensile strength of the PLA/PMMA/SiO2 composites by ∼43%, and both a chain extender and nanosilica particles increase Young's modulus and Izod impact strength of the composites. Including 0.5 wt % nanosilica particles increase the elongation at break and Izod impact strength by ∼287 and 163%, respectively, compared with those of the neat PLA. On account of the mechanical performances, the optimal blending ratio may be between PLA/PMMA/SiO2 (90/10) and PLA/PMMA/SiO2 (80/20). The total light transmittance of the PLA/PMMA/SiO2 composites reaches as high as 91%, indicating a high miscible PLA/PMMA blend. The haze value of the PLA/PMMA/SiO2 composites is less than 35%. Incorporating nanosilica particles can increase the crystallization sites and crystallinities of the PLA/PMMA/SiO2 composites with a simultaneous decrease of the spherulite dimension. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42378.
Preparation and properties of compatible starch‐polycaprolactone composites: Effects of molecular weight of soft segments in polyurethane compatilizer
Authors: Zhang Xu , Zhang Yu , Liao Jingjing , Yu Ting , Hu Rongrong , Wu Zhengshun , Wu Qiangxian
Published: May 2015

In this study, polycaprolactone (PCL)‐diol samples of soft segment with different molecular weights were utilized to synthesiz polyurethane prepolymer (PCLPUP) and was charged in an intensive mixer to prepare starch‐PCLPU‐PCL composites. The impact of the polyurethane soft segments with different molecular weights on the starch‐PCLPI‐PCL composite systems regarding their structure and properties, were thoroughly analyzed. Results showed that the PCLPU successfully increased the interaction between the starch and PCL in the composites, and can thus be used as an effective compatilizer to improve the compatibility between starch and PCL in the resultant composites. With decreasing molecular weight of PCLPU soft segments, the isocyanate group (NCO) content in the PCLPU increased, generating more urethane covalent bonds between PCLPU and starch, thereby enhancing the interaction between starch and PCLPU interface. Again, with decreasing molecular weight of PCLPU soft segments, the physical cross‐linking between the PCLPU and PCL was increased, thereby enhancing the compatibility between PCL matrix and PCLPU interface. Owing to the improvement of compatibility between the starch filler and PCL matrix, the elongation and strength at break for the composite material likewise improved after the addition of PCLPU soft segments with low molecular weight. To this effect, a PCLPU soft segment with low molecular weight was added to the starch‐PCL composites system to boost the overall performance of these starch‐PCL composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42381.
Electrical properties of acrylic resin composite thin films with graphene/silver nanowires
Authors: Wang Xiaoxia , Pang Beili , Zhu Qianqian , Yu Jianhua , Dong Hongzhou , Dong Lifeng
Published: May 2015

Silver nanowires and graphene were used to form networks within acrylic resin to improve its toughness and conductivity through silane coupling agent. Meanwhile, acrylic resin was favorable to the adhesion of graphene to glass substrates and the connection among graphene sheets to form films. Experimental results indicate that after annealing at 400°C, sheet resistances of graphene‐silver nanowire films were lower than those graphene films without silver nanowires. The findings in this study provide helpful information on the fabrication of graphene‐based electronic devices. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42387.
Effect of surfactant and electron treatment on the electrical and thermal conductivity as well as thermal and mechanical properties of ethylene vinyl acetate/expanded graphite composites
Authors: Sefadi Jeremia Shale , Luyt Adriaan Stephanus , Pionteck Jürgen , Piana Francesco , Gohs Uwe
Published: May 2015

This study presents an investigation of the electrical and thermal conductivities of composites based on an ethylene vinyl acetate (EVA) copolymer matrix and nanostructured expanded graphite (EG). To improve the EG dispersion in EVA, EG sheets were modified by treating them with the anionic surfactant sodium dodecyl sulphate (SDS) in water. The modified SDS‐EG platelets, after being filtered and dried, were melt‐mixed with EVA to prepare the composites. Finally, both EVA/EG and EVA/SDS‐EG composites were subjected to 50 kGy electron beam (EB) irradiation. SEM images confirm that the irradiated EVA/EG samples had improved interfacial adhesion, while the irradiated EVA/SDS‐EG samples showed even better interfacial adhesion. The gel contents of the irradiated samples without and with SDS treatment increased with increase in EG loading. The EVA/EG composites exhibited a sharp transition from an insulator to a conductor at an electrical percolation threshold of 8 wt %, but with SDS‐EG the electrical conductivity was extremely low, showing no percolation up to 10 wt % of filler. The EB irradiation had no influence on electrical conductivity. The thermal conductivity linearly increased with EG content, and this increase was more pronounced in the case of SDS‐EG, but decreased after EB irradiation. The thermal properties were little influenced by EB irradiation, while better polymer–filler interaction and better filler dispersion as a result of SDS treatment, and the EB irradiation initiated formation of a cross‐linked network, had a positive effect on the tensile properties. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42396.
A biomimetic surface treatment to obtain durable omniphobic textiles
Authors: De Marco Carmela , Oldani Valeria , Bianchi Claudia Letizia , Levi Marinella , Turri Stefano
Published: May 2015

A bio‐inspired surface treatment to make fabrics omniphobic is reported, exploiting the ability of dopamine – a widespread naturally occurring biological neurotransmitter – to give substrate adhesion and surface immobilization. Standard polyester and polyacrylonitrile fabrics, which are intrinsically rather hydrophilic, are first dip‐coated in an aqueous solution of dopamine and then treated with a fluorocarbon‐based solution. After the treatment, fabrics show a strong omniphobic behavior, while remaining quite permeable to water vapor. The efficiency of the proposed biomimetic treatment is investigated by Optical Contact Angle, Environmental Scanning Electron Microscopy (ESEM), and X‐ray Photoelectron Spectroscopy (XPS). Moreover, the mechanical durability of the surface treatment is tested through Martindale abrasion resistance measurements. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42404.
Silk fibroin composite membranes for application in corneal regeneration
Authors: Zhang Shanshan , Li Jiaojiao , Yin Zhuping , Zhang Xiaofeng , Kundu Subhas C. , Lu Shenzhou
Published: May 2015

The ordered microstructure of the corneal stroma determines the transparency of the cornea. The difficulty of constructing three‐dimensional corneal tissue mainly lies in the reconstruction of the corneal stroma. This article reports propionamide/silk fibroin composite membrane materials for use in corneal regeneration. X‐ray diffraction is used to explore the structure of the composite fibroin membrane. Propionamide acts as a crosslinking agent and inhibits the formation of larger crystal grains controlling the crystallization process. Corneal stromal cells are seeded on sterilized composite films. Propionamide/fibroin membranes with different blending proportions exhibit stable transparency and good cell compatibility. The results demonstrate that composite fibroin membranes are suitable potential materials for use in corneal stromal cell proliferation and repair. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42407.
Differential β3 and β1 Integrin Expression in Bone Marrow and Cortical Bone of Estrogen Deficient Rats
Authors: Voisin Muriel , McNamara Laoise M.
Published: May 2015

Integrin‐based (β3) attachments to the extracellular matrix (ECM) on osteocyte cell processes have recently been proposed to play an important role in facilitating osteocyte mechanosensation. However, it is not yet known whether integrin expression is altered in the mechanoregulatory osteocytes during osteoporosis. The objective of this study was to test the hypothesis that the expression of integrin‐based mechanosensory complexes (β1 and β3 integrins) is altered as a direct response to estrogen deficiency, in an estrogen deficient animal model of osteoporosis. Four weeks post‐operatively, immunohistochemistry was used to detect for β1 and β3 integrin subunits in bone tissue and marrow of ovariectomized (OVX; N = 4) and SHAM (N = 4) operated animals. A tartrate resistant acid phosphatase (TRAP) control stain was performed to quantify the presence of osteoclasts in the bone marrow and bone surfaces. Image analysis was performed to quantify expression patterns in different biological compartments, that is, bone marrow, endosteum, and cortical bone. Our results showed that β1 integrins were ubiquitously expressed throughout the bone and marrow, for both OVX and SHAM groups. β3 integrin subunit expression was lower in bone cells from osteoporotic animals compared to controls, whereas β3 expression in marrow cells did not differ significantly between groups. At the endosteum no difference was observed in β3 integrin subunit expression. As expected, the number of osteoclasts was higher in the OVX group validating an imbalance in bone remodeling. We propose that a reduction in β3 integrin expression in osteocytes might impair mechanosensation by bone cells during estrogen deficiency. Anat Rec, 298:1548–1559, 2015. © 2015 Wiley Periodicals, Inc.
Enzymatic cell disruption of microalgae biomass in biorefinery processes
Authors: Demuez Marie , Mahdy Ahmed , Tomás‐Pejó Elia , González‐Fernández Cristina , Ballesteros Mercedes
Published: May 2015

When employing biotechnological processes for the procurement of biofuels and bio‐products from microalgae, one of the most critical steps affecting economy and yields is the “cell disruption” stage. Currently, enzymatic cell disruption has delivered effective and cost competitive results when compared to mechanical and chemical cell disruption methods. However, the introduction of enzymes implies additional associated cost within the overall process. In order to reduce this cost, autolysis of microalgae is proposed as alternative enzymatic cell disruption method. This review aims to provide the state of the art of enzymatic cell disruption treatments employed in biorefinery processes and highlights the use of endopeptidases. During the enzymatic processes of microalgae life cycle, some lytic enzymes involved in cell division and programmed cell death have been proven useful in performing cell lysis. In this context, the role of endopeptidases is emphasized. Mirroring these natural events, an alternative cell disruption approach is proposed and described with the potential to induce the autolysis process using intrinsic cell enzymes. Integrating induced autolysis within biofuel production processes offers a promising approach to reduce overall global costs and energetic input associated with those of current cell disruption methods. A number of options for further inquiry are also discussed. Biotechnol. Bioeng. 2015;112: 1955–1966. © 2015 Wiley Periodicals, Inc.
Systematic review of cardiovascular disease and cardiovascular death in patients with a small abdominal aortic aneurysm
Authors: Bath M F , Gokani V J , Sidloff D A , Jones L R , Choke E , Sayers R D , Bown M J
Published: May 2015

Background

Screening for abdominal aortic aneurysm (AAA) has reduced the rate of AAA rupture. However, cardiovascular disease is still a major cause of death in men with an AAA. The aim of this study was to assess cardiovascular risk in patients with a small AAA.

Methods

Standard PRISMA guidelines were followed. Analysis was performed of studies reporting cardiovascular outcomes in patients with a small AAA (30–54 mm). Weighted metaregression was performed for cardiovascular death in patients with a small AAA, and the prevalence of cardiovascular disease was reviewed.

Results

Twenty-one articles were identified describing patients with an AAA, and the prevalence of, and death from, cardiovascular disease. Ten of these reported cardiovascular death rates in patients with a small AAA. Some 2323 patients with a small AAA were identified; 335 cardiovascular deaths occurred, of which 37 were due to AAA rupture. Metaregression demonstrated that the risk of cardiovascular death was 3·0 (95 per cent c.i. 1·7 to 4·3) per cent per year in patients with a small AAA (R2 = 0·902, P < 0·001). The prevalence of ischaemic heart disease (44·9 per cent), myocardial infarction (26·8 per cent), heart failure (4·4 per cent) and stroke (14·0 per cent) was also high in these patients.

Conclusion

The risk of cardiovascular death in patients with a small AAA is high and increases by approximately 3 per cent each year after diagnosis. Patients with a small AAA have a high prevalence of cardiovascular disease. Patients a small AAA should be considered for lifestyle modifications and secondary cardiovascular protection.
Frozen moments: flashback memories of critical incidents in emergency personnel
Authors: Kleim Birgit , Bingisser Martina‐Barbara , Westphal Maren , Bingisser Roland
Published: May 2015

Background

Emergency Department personnel regularly face highly stressful situations or critical incidents (CIs) that may subsequently be recalled as unbidden intrusive memories. In their most extreme form, such memories are reexperienced as if they were happening again in the present, as flashbacks. This study examined (1) which CIs are associated with flashback memories; (2) candidate person and work‐related features that predict flashback memories; and (3) the association between flashback memories and anxiety, depression, and emotional exhaustion.

Methods

Emergency nurses (N = 91; 80.2% female) were recruited from two urban teaching hospitals and filled in self‐report questionnaires.

Results

A majority (n = 59, 65%) experienced intrusive memories; almost half of the sample reported that their memories had flashback character. Those involved in resuscitations in the past week were at a fourfold risk for experiencing flashbacks. Having worked more consecutive days without taking time off was associated with a somewhat lower incidence of flashbacks. Moreover, older individuals who reported more work‐related conflicts were at greater risk for experiencing flashback memories than their younger colleagues with heightened work conflict and flashback memory scores, respectively. Flashback memories were associated with heightened symptoms of anxiety, depression, and emotional exhaustion.

Conclusions

The present findings have implications for evidence‐based health promotion in emergency personnel and other individuals regularly exposed to CIs.
Clinical cardiac structural anatomy reconstructed within the cardiac contour using multidetector‐row computed tomography: Left ventricular outflow tract
Authors: Mori Shumpei , Fukuzawa Koji , Takaya Tomofumi , Takamine Sachiko , Ito Tatsuro , Fujiwara Sei , Nishii Tatsuya , Kono Atsushi K , Yoshida Akihiro , Hirata Ken‐Ichi
Published: May 2015

The left ventricular outflow tract (LVOT) is a common site of idiopathic ventricular arrhythmia. Many electrocardiographic characteristics for predicting the origin of arrhythmia have been reported, and their prediction rates are clinically acceptable. Because these approaches are inductive, based on QRS‐wave morphology during the arrhythmia and endocardial or epicardial pacing, three‐dimensional anatomical accuracy in identifying the exact site of the catheter position is essential. However, fluoroscopic recognition and definition of the anatomy around the LVOT can vary among operators, and three‐dimensional anatomical recognition within the cardiac contour is difficult because of the morphological complexity of the LVOT. Detailed knowledge about the three‐dimensional fluoroscopic cardiac structural anatomy could help to reduce the need for contrast medium injection and radiation exposure, and to perform safe interventions. In this article, we present a series of structural images of the LVOT reconstructed in combination with the cardiac contour using multidetector‐row computed tomography. We also discuss the clinical implications of these findings based on the accumulated insights of research pioneers. Clin. Anat. 29:353–363, 2016. © 2015 Wiley Periodicals, Inc.
Clinical cardiac structural anatomy reconstructed within the cardiac contour using multidetector‐row computed tomography: The arrangement and location of the cardiac valves
Authors: Mori Shumpei , Fukuzawa Koji , Takaya Tomofumi , Takamine Sachiko , Ito Tatsuro , Fujiwara Sei , Nishii Tatsuya , Kono Atsushi K. , Yoshida Akihiro , Hirata Ken‐Ichi
Published: May 2015

It is essential for the interventional cardiologist to have in‐depth anatomical information about the three‐dimensional arrangement and location of the cardiac valves relative to the various projections of the cardiac contour as revealed fluoroscopically. Multidetector‐row computed tomography is useful for providing information about the three‐dimensional arrangements of each structure. This article presents cardiac structural images, focusing on the arrangement and location of the cardiac valves, which were reconstructed with the cardiac contour and surrounding structures using multidetector‐row computed tomography. We discuss the clinical implications of the findings. We hope these images will serve as a bridge between cardiology, radiology, and anatomy, and will prompt scientists in the field of cardiology to integrate their accumulated insights into three‐dimensional clinical images of the living heart. Clin. Anat. 29:364–370, 2016. © 2015 Wiley Periodicals, Inc.
Are medical students being taught anatomy in a way that best prepares them to be a physician?
Authors: Meral Savran Mona , Tranum‐Jensen Jørgen , Frost Clementsen Paul , Hastrup Svendsen Jesper , Holst Pedersen Jesper , Seier Poulsen Steen , Arendrup Henrik , Konge Lars
Published: May 2015

Reasoning in a clinical context is an attribute of medical expertise. Clinical reasoning in medical school can be encouraged by teaching basic science with a clinical emphasis. The aim of this study was to investigate whether anatomy is being taught in a way that facilitates the development of clinical reasoning. Two multiple‐choice tests on thoracic anatomy were developed using a modified Delphi approach with groups of four clinical consultants and four teachers, respectively, expressing their opinions about knowledge relevant to thoracic anatomy. Validity was assessed by administering the tests to clinical consultants, anatomy teachers, and pre‐course medical students. Post‐course medical students took both tests to explore the focus of the course, i.e., whether it facilitated clinical reasoning. The pre‐course students scored significantly lower than the teachers and post‐course students on both tests and lower than the consultants on the consultants’ test (P < 0.001 for all comparisons). The teachers significantly outperformed the consultants (P = 0.03 on the consultants’ test, P < 0.001 on the teachers’ test) and the medical students (P < 0.001 on both tests). The post‐course students scored significantly lower on the consultants’ test (P = 0.001) and significantly higher on the teachers’ test (P = 0.02) than the consultants. This study demonstrates poor performances by medical students on a test containing clinically relevant anatomy, implying that the teaching they have received has not encouraged clinical reasoning. Clin. Anat. 28:568–575, 2015. © 2015 Wiley Periodicals, Inc.
Verification of a standardized method for inserting intramuscular electromyography electrodes into teres minor using ultrasound
Authors: Rathi Sangeeta , Zacharias Anita , Green Rodney A.
Published: May 2015

The close proximity of the infraspinatus to the teres minor and their functional similarity in producing external rotation of the glenohumeral joint make accurate insertion of electromyographic (EMG) electrodes into the teres minor difficult and questionable even when published guidelines are followed. The primary aim of this study was to examine the anatomical support for the current guidelines for inserting intramuscular EMG electrodes into the teres minor muscle. The secondary aim was to provide a technical description for ultrasound‐guided electrode insertion into the teres minor. Intramuscular electrodes were inserted into four cadaveric shoulders using markings based on the current guidelines. EMG electrodes were also inserted into the teres minor of four healthy male participants using real‐time ultrasound (RTUS) guidance. Systematic dissections of the cadaver specimens revealed that the electrode had been successfully inserted into the teres minor muscle in only one out of the four. In the remaining three specimens, the needle lodged in the infraspinatus muscle belly at distances ranging from 3 to 17 mm medial to the teres minor. Using RTUS guidance, the electrodes were successfully inserted into the teres minor in all participants, as confirmed by visual inspection with RTUS. This study confirms that the current EMG electrode insertion guidelines for the teres minor are not accurate and RTUS ensures the placement of electrodes into the teres minor rather than the adjacent infraspinatus muscle. Clin. Anat. 28:780–785, 2015. © 2015 Wiley Periodicals, Inc.
Identifying Etiologically Distinct Sub‐Types of Cancer: A Demonstration Project Involving Breast Cancer
Authors: Begg Colin B. , Orlow Irene , Zabor Emily C. , Arora Arshi , Sharma Ajay , Seshan Venkatraman E. , Bernstein Jonine L.
Published: May 2015

With the advent of increasingly detailed molecular portraits of tumor specimens, much attention has been directed toward identifying clinically distinct subtypes of cancer. Subtyping of tumors can also be accomplished with the goal of identifying distinct etiologies. We demonstrate the use of new methodologies to identify genes that distinguish etiologically heterogeneous subtypes of breast cancer using data from the case–control Cancer and Steroid Hormone Study. Tumor specimens were evaluated using a breast cancer expression panel of 196 genes. Using a statistical measure that distinguishes the degree of etiologic heterogeneity in tumor subtypes, each gene is ranked on the basis of its ability to distinguish etiologically distinct subtypes. This is accomplished independently using case–control comparisons and by examining the concordance odds ratios in double primaries. The estrogen receptor gene, and others in this pathway with expression levels that correlated strongly with estrogen receptor levels, demonstrate high degrees of etiologic heterogeneity in both methods. Our results are consistent with a growing literature that confirms the distinct etiologies of breast cancers classified on the basis of estrogen receptor expression levels. This proof‐of‐principle project demonstrates the viability of new strategies to identify genomic features that distinguish subtypes of cancer from an etiologic perspective.
Reserve price and competing bids: Reference points for product evaluations in online auctions?
Authors: Trautmann Stefan T. , van de Kuilen Gijs
Published: May 2015

With an increasing number of products sold in online auctions, the effect of reference points on consumers' product valuations has received much attention in the literature. Two potentially relevant factors affecting bidders' preferences are the sellers' reserve price and the competing bids by other bidders. The current evidence regarding these reference points is mixed. We argue that a focus on studying bids prevents a clear identification of reference point effects. Directly observing product valuations, in two experiments, we find that willingness to pay in online auctions is affected by both reserve prices and competing bids, supporting the constructed values paradigm. Copyright © 2015 John Wiley & Sons, Ltd.
Designed Intercalators for Modification of DNA Origami Surface Properties
Authors: Brglez Josipa , Nikolov Pavel , Angelin Alessandro , Niemeyer Christof M.
Published: May 2015

The modification of the backbone properties of DNA origami nanostructures through noncovalent interactions with designed intercalators, based on acridine derivatized with side chains containing esterified fatty acids or oligo(ethylene glycol) residues is reported. Spectroscopic analyses indicate that these intercalators bind to DNA origami structures. Atomic force microscopy studies reveal that intercalator binding does not affect the structural intactness but leads to altered surface properties of the highly negatively charged nanostructures, as demonstrated by their interaction with solid mica or graphite supports. Moreover, the noncovalent interaction between the intercalators and the origami structures leads to alteration in cellular uptake, as shown by confocal microscopy studies using two different eukaryotic cell lines. Hence, the intercalator approach offers a potential means for tailoring the surface properties of DNA nanostructures.