bluuebunny/crossref_metadata_2025 huggingface dataset:
Large volcanic eruptions cause drought in eastern China
Authors: Schultz Colin
Published: September 2014

In most cases, the annual East Asian Monsoon brings heavy rains and widespread flooding to southeast China and drought conditions to the northeast. At various points throughout history, however, large volcanic eruptions have upset the regular behavior of the monsoon.
Using a Bayesian hierarchical model to improve Lake Erie cyanobacteria bloom forecasts
Authors: Obenour Daniel R. , Gronewold Andrew D. , Stow Craig A. , Scavia Donald
Published: September 2014

The last decade has seen a dramatic increase in the size of western Lake Erie cyanobacteria blooms, renewing concerns over phosphorus loading, a common driver of freshwater productivity. However, there is considerable uncertainty in the phosphorus load‐bloom relationship, because of other biophysical factors that influence bloom size, and because the observed bloom size is not necessarily the true bloom size, owing to measurement error. In this study, we address these uncertainties by relating late‐summer bloom observations to spring phosphorus load within a Bayesian modeling framework. This flexible framework allows us to evaluate three different forms of the load‐bloom relationship, each with a particular combination of statistical error distribution and response transformation. We find that a novel implementation of a gamma error distribution, along with an untransformed response, results in a model with relatively high predictive skill and realistic uncertainty characterization, when compared to models based on more common statistical formulations. Our results also underscore the benefits of a hierarchical approach that enables assimilation of multiple sets of bloom observations within the calibration processes, allowing for more thorough uncertainty quantification and explicit differentiation between measurement and model error. Finally, in addition to phosphorus loading, the model includes a temporal trend component indicating that Lake Erie has become increasingly susceptible to large cyanobacteria blooms over the study period (2002–2013). Results suggest that current phosphorus loading targets will be insufficient for reducing the intensity of cyanobacteria blooms to desired levels, so long as the lake remains in a heightened state of bloom susceptibility.
Stepped Moduli in Layered Composites
Authors: So Ju‐Hee , Tayi Alok S. , Güder Firat , Whitesides George M.
Published: September 2014

This paper describes adaptive composites that respond to mechanical stimuli by changing their Young's modulus. These composites are fabricated by combining a shorter layer of elastic material (e.g., latex) and a longer layer of stiffer material (e.g., polyethylene and Kevlar), and fixing them together at their ends. Tension along the layered composite increases its length, and as the strain increases, the composite changes the load‐bearing layer from the elastic to the stiff material. The result is a step in the Young's modulus of the composite. The characteristics of the step (or steps) can be engineered by changing the constituent materials, the number of layers, and their geometries (e.g., sinusoidal, hierarchical, two‐dimensional web‐like, rod‐coil, embedded, and ring structures). For composites with more than two steps in modulus, the materials within the composites can be layered in a hierarchical structure to fit within a smaller volume, without sacrificing performance. These composites can also be used to make structures with tunable, stepped compressive moduli. An adaptation of these principles can generate an electronic sensor that can monitor the applied compressive strain. Increasing or decreasing the strain closes or opens a circuit and reversibly activates a light‐emitting diode.
A High Power‐Density, Mediator‐Free, Microfluidic Biophotovoltaic Device for Cyanobacterial Cells
Authors: Bombelli Paolo , Müller Thomas , Herling Therese W. , Howe Christopher J. , Knowles Tuomas P. J.
Published: September 2014

Biophotovoltaics has emerged as a promising technology for generating renewable energy because it relies on living organisms as inexpensive, self‐repairing, and readily available catalysts to produce electricity from an abundant resource: sunlight. The efficiency of biophotovoltaic cells, however, has remained significantly lower than that achievable through synthetic materials. Here, a platform is devised to harness the large power densities afforded by miniaturized geometries. To this effect, a soft‐lithography approach is developed for the fabrication of microfluidic biophotovoltaic devices that do not require membranes or mediators. Synechocystis sp. PCC 6803 cells are injected and allowed to settle on the anode, permitting the physical proximity between cells and electrode required for mediator‐free operation. Power densities of above 100 mW m‐2 are demonstrated for a chlorophyll concentration of 100 μM under white light, which is a high value for biophotovoltaic devices without extrinsic supply of additional energy.
C–N cross‐coupling reaction catalysed by efficient and reusable CuO/SiO2 nanoparticles under ligand‐free conditions
Authors: Hajipour Abdol R. , Dordahan Fatemeh , Rafiee Fatemeh , Mahdavi Mohammad
Published: September 2014

Nanometric copper oxide supported on silica has been found to be a highly efficient and reusable catalyst for the C–N cross‐coupling reaction of amines with aryl halides under ligand‐free conditions. Various arylamines with different substituted groups can be synthesized in moderate to good yields. The catalyst can be recycled at least five times without obvious loss in catalytic activity. Copyright © 2014 John Wiley & Sons, Ltd.
Cure efficiency of dodecyl succinic anhydride as a cross‐linking agent for elastomer blends based on epoxidized natural rubber
Authors: Mascia Leno , Clarke Jane , Ng Kiat Seong , Chua Kok Sien , Russo Pietro
Published: September 2014

Blends of a highly epoxidized natural rubber (ENR50) with unmodified natural rubber (NR) and ethylene propylene elastomers (EPDM) were produced to evaluate the mixing and curing characteristics. Dodecyl succinic anhydride was used to cross‐link the ENR50 component and the reactivity was assessed by monitoring the evolution of the torque in an oscillatory co‐axial cylinder rheometer, as well as by DSC thermal analysis. A physical model was used to obtain a single parameter for the reactivity of the system, which corresponds to the rate constant for first order curing reactions. Although the blends were thermodynamically immiscible, displaying no significant change in Tg, the components were well dispersed at microscopic level. Better mechanical properties were obtained for blends with EPDM. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41448.
Santiago Ramón y Cajal: The Cajal Institute and the Spanish Histological School
Authors: De Carlos Juan A. , Pedraza MarÍa
Published: September 2014

Santiago Ramón y Cajal was a self‐taught researcher. He almost always worked alone, usually in the solitude of his private laboratory installed at his home. He was also a university professor and therefore taught histology and pathology to many students. But because research laboratories were scarce and poorly equipped, he preferred to organize courses and tutor at home as well. For this reason, Cajal left a faint trace of disciples in the three academic chairs that he came to occupy. It may be argued that Cajal formed the histological school when the Spanish government decided to support his investigations and created a scientific laboratory for him, with funding to cover the cost of journals, instruments, materials, personnel, and so forth. This support occurred in the year 1902, after Cajal received the Moscow Prize. Some of his former students accompanied Cajal to the new laboratory. Upon receipt of new awards, including the Gold Medal of von Helmholtz (1905) and the Nobel Prize in Physiology or Medicine (1906), Cajal's popularity increased and a large number of students wanted to learn about the laboratory and work with the great Cajal. This review tells this history. But we realize that this is not an easy task because to be fair to all the people that formed the Spanish Histological School, we would need to write a book. This is not practical. Instead, selection of contributors to the formation of the Spanish Histological School is provided. At the same time, some brushstrokes of the story extend to and include the Cajal Institute, which ran in parallel with the Spanish Histological School. Anat Rec, 297:1785–1802, 2014. © 2014 Wiley Periodicals, Inc.
Neural crest cells: From developmental biology to clinical interventions
Authors: Noisa Parinya , Raivio Taneli
Published: September 2014

Neural crest cells are multipotent cells, which are specified in embryonic ectoderm in the border of neural plate and epiderm during early development by interconnection of extrinsic stimuli and intrinsic factors. Neural crest cells are capable of differentiating into various somatic cell types, including melanocytes, craniofacial cartilage and bone, smooth muscle, and peripheral nervous cells, which supports their promise for cell therapy. In this work, we provide a comprehensive review of wide aspects of neural crest cells from their developmental biology to applicability in medical research. We provide a simplified model of neural crest cell development and highlight the key external stimuli and intrinsic regulators that determine the neural crest cell fate. Defects of neural crest cell development leading to several human disorders are also mentioned, with the emphasis of using human induced pluripotent stem cells to model neurocristopathic syndromes. Birth Defects Research (Part C) 102:263–274, 2014. © 2014 Wiley Periodicals, Inc.
Evolutionary and developmental origins of the cardiac neural crest: Building a divided outflow tract
Authors: Keyte Anna L. , Alonzo‐Johnsen Martha , Hutson Mary R.
Published: September 2014

The cardiac neural crest cells (CNCCs) have played an important role in the evolution and development of the vertebrate cardiovascular system: from reinforcement of the developing aortic arch arteries early in vertebrate evolution, to later orchestration of aortic arch artery remodeling into the great arteries of the heart, and finally outflow tract septation in amniotes. A critical element necessary for the evolutionary advent of outflow tract septation was the co‐evolution of the cardiac neural crest cells with the second heart field. This review highlights the major transitions in vertebrate circulatory evolution, explores the evolutionary developmental origins of the CNCCs from the third stream cranial neural crest, and explores candidate signaling pathways in CNCC and outflow tract evolution drawn from our knowledge of DiGeorge Syndrome. Birth Defects Research (Part C) 102:309–323, 2014. © 2014 Wiley Periodicals, Inc.
The neural crest: A versatile organ system
Authors: Zhang Dongcheng , Ighaniyan Samiramis , Stathopoulos Lefteris , Rollo Benjamin , Landman Kerry , Hutson John , Newgreen Donald
Published: September 2014

The neural crest is the name given to the strip of cells at the junction between neural and epidermal ectoderm in neurula‐stage vertebrate embryos, which is later brought to the dorsal neural tube as the neural folds elevate. The neural crest is a heterogeneous and multipotent progenitor cell population whose cells undergo EMT then extensively and accurately migrate throughout the embryo. Neural crest cells contribute to nearly every organ system in the body, with derivatives of neuronal, glial, neuroendocrine, pigment, and also mesodermal lineages. This breadth of developmental capacity has led to the neural crest being termed the fourth germ layer. The neural crest has occupied a prominent place in developmental biology, due to its exaggerated migratory morphogenesis and its remarkably wide developmental potential. As such, neural crest cells have become an attractive model for developmental biologists for studying these processes. Problems in neural crest development cause a number of human syndromes and birth defects known collectively as neurocristopathies; these include Treacher Collins syndrome, Hirschsprung disease, and 22q11.2 deletion syndromes. Tumors in the neural crest lineage are also of clinical importance, including the aggressive melanoma and neuroblastoma types. These clinical aspects have drawn attention to the selection or creation of neural crest progenitor cells, particularly of human origin, for studying pathologies of the neural crest at the cellular level, and also for possible cell therapeutics. The versatility of the neural crest lends itself to interlinked research, spanning basic developmental biology, birth defect research, oncology, and stem/progenitor cell biology and therapy. Birth Defects Research (Part C) 102:275–298, 2014. © 2014 Wiley Periodicals, Inc.
Exploring the role of discourse in marketing and consumer research
Authors: Fitchett James , Caruana Robert
Published: September 2014

This paper reviews the development of discourse‐based analysis in marketing and consumer research and outlines the application of various forms of discourse analysis (DA) as an approach. The paper locates this development alongside broader disciplinary movements and restates the potential for critical DA (CDA) in marketing and consumer behaviour research. We argue that discourse‐based approaches have considerable potential and application particularly in terms of supporting disciplinary reflexivity and research criticality. A discursive lens offers novel ways of understanding marketing as a subject/discipline as well as how marketing academics conceive and investigate objects of marketing inquiry. The objectives of this paper are fourfold: to outline the development of discourse and text‐based studies in marketing and consumer research; to reveal how this has shaped, framed and limited the application and utilisation of DA in particular ways; to synthesise the main principles of DA generally and CDA specifically; and highlight how these approaches could be applied to a range of marketing and consumer behaviour issues and contexts. Copyright © 2014 John Wiley & Sons, Ltd.
Evolutionarily conserved organization of the dopaminergic system in lamprey: SNc/VTA afferent and efferent connectivity and D2 receptor expression
Authors: Pérez‐Fernández Juan , Stephenson‐Jones Marcus , Suryanarayana Shreyas M. , Robertson Brita , Grillner Sten
Published: September 2014

The dopaminergic system influences motor behavior, signals reward and novelty, and is an essential component of the basal ganglia in all vertebrates including the lamprey, one of the phylogenetically oldest vertebrates. The intrinsic organization and function of the lamprey basal ganglia is highly conserved. For instance, the direct and indirect pathways are modulated through dopamine D1 and D2 receptors in lamprey and in mammals. The nucleus of the tuberculum posterior, a homologue of the substantia nigra pars compacta (SNc)/ventral tegmental area (VTA) is present in lamprey, but only scarce data exist about its connectivity. Likewise, the D2 receptor is expressed in the striatum, but little is known about its localization in other brain areas. We used in situ hybridization and tracer injections, both in combination with tyrosine hydroxylase immunohistochemistry, to characterize the SNc/VTA efferent and afferent connectivity, and to relate its projection pattern with D2 receptor expression in particular. We show that most features of the dopaminergic system are highly conserved. As in mammals, the direct pallial (cortex in mammals) input and the basal ganglia connectivity with the SNc/VTA are present as part of the evaluation system, as well as input from the tectum as the evolutionary basis for salience/novelty detection. Moreover, the SNc/VTA receives sensory information from the olfactory bulbs, optic tectum, octavolateral area, and dorsal column nucleus, and it innervates, apart from the nigrostriatal pathway, several motor‐related areas. This suggests that the dopaminergic system also contributes to the control of different motor centers at the brainstem level. J. Comp. Neurol. 522:3775–3794, 2014. © 2014 Wiley Periodicals, Inc.
Evidence of local short‐distance spawning migration of tropical freshwater eels, and implications for the evolution of freshwater eel migration
Authors: Arai Takaomi
Published: September 2014

Freshwater eels have fascinated biologists for centuries due to the spectacular long‐distance migrations between the eels’ freshwater habitats and their spawning areas far out in the ocean and the mysteries of their ecology. The spawning areas of Atlantic eels and Japanese eel were located far offshore in the Atlantic Ocean and the Pacific Ocean, respectively, and their reproduction took place thousands of kilometers away from their growth habitats. Phylogenetic studies have revealed that freshwater eels originated in the Indonesian region. However, remarkably little is known about the life histories of tropical freshwater eels despite the fact that tropical eels are key to understanding the nature of primitive forms of catadromous migration. This study found spawning‐condition tropical freshwater eels in Lake Poso, central Sulawesi, Indonesia, with considerably high gonadosomatic index values and with histologically fully developed gonads. This study provides the first evidence that under certain conditions, freshwater eels have conditions that are immediately able to spawn even in river downstream. The results suggest that, in contrast to the migrations made by the Atlantic and Japanese eels, freshwater eels originally migrated only short distances of <100 kilometers to local spawning areas adjacent to their freshwater growth habitats. Ancestral eels most likely underwent a catadromous migration from local short‐distance movements in tropical coastal waters to the long‐distance migrations characteristic of present‐day temperate eels, which has been well established as occurring in subtropical gyres in both hemispheres.
Dust effects on snowpack melt and related ecosystem processes are secondary to those of forest canopy structure and interannual snowpack variability
Authors: Maurer Gregory E. , Bowling David R.
Published: September 2014

Dust deposition lowers the albedo of snow and can significantly alter snowpack energy balance. Investigation of aeolian dust deposition in the mountains of the western U.S. has shown that these effects advance the timing of snowpack melt and spring runoff across much of the region. These studies have primarily focused on alpine snowpacks with little to no overstory vegetation. To evaluate the impacts of aeolian dust on ecohydrological processes in forests, we conducted a manipulative experiment in a subalpine conifer forest in Utah's Wasatch Mountains. During the spring of 2010–2012, we added dust to the snow surface in forested plots every 1 to 2 weeks, roughly doubling the natural dust loading. We then measured snowpack ablation in control and dust addition plots, along with below‐snowpack and warm season soil temperature (Tsoil), soil water content (θ), litter decomposition rate (D), soil respiration rate (Rs), and tree xylem water potential (ψ). Differences in ablation between control and dust addition plots were similar in magnitude to differences associated with the canopy structure of the forest. Seasonal patterns in Tsoil and θ were similar between dust treatments and canopy structure groups. D, Rs, and ψ varied little between dust treatments, but there were significant differences between years. During our 3‐year study, an unusual level of interannual variability in snowfall had the greatest effect on the soil environment and ecosystem processes. The effects of aeolian dust on snowpack mass and energy balance in our forest were slightly smaller than those associated with canopy structure. Copyright © 2014 John Wiley & Sons, Ltd.
Comparing two approaches for parsimonious vegetation modelling in semiarid regions using satellite data
Authors: Pasquato Marta , Medici Chiara , Friend Andrew D. , Francés Félix
Published: September 2014

Large portions of Earth's terrestrial surface are arid or semiarid. As in these regions, the hydrological cycle and the vegetation dynamics are tightly interconnected, a coupled modelling of these two systems is needed to fully reproduce the ecosystem behaviour. In this paper, the performance of two parsimonious dynamic vegetation models, suitable for the inclusion in operational ecohydrological models and based on well‐established but different approaches, is compared in a semiarid Aleppo Pine region. The first model [water use efficiency (WUE) model] links growth to transpiration through WUE; the second model [light use efficiency (LUE) model] simulates biomass increase in relation to absorbed photosynthetically active radiation and LUE. Furthermore, an analysis of the information contained in MODIS products is presented to indicate the best vegetation indices to be used as observational verification for the models. Enhanced Vegetation Index is reported in literature to be highly correlated with leaf area index, so it is compared with modelled LAImod (rWUE model = 0.45; rLUE model = 0.57). In contrast, Normalized Difference Vegetation Index appears highly linked to soil moisture, through the control exerted by this variable on chlorophyll production, and is therefore used to analyze LAI*mod, models' output corrected by plant water stress (rWUE model = 0.62; rLUE model = 0.59). Moderate‐resolution imaging spectroradiometer Leaf Area Index and evapotranspiration are found to be unrealistic in the studied area. The performance of both models in this semiarid region is found to be reasonable. However, the LUE model presents the advantages of a better performance, the possibility to be used in a wider range of climates and to have been extensively tested in literature. Copyright © 2014 John Wiley & Sons, Ltd.
Chain Extension of Boronic Esters with Lithiooxiranes Generated by Sulfoxide–Metal Exchange – Stereocontrolled Access to 2°/2°, 2°/3°, and 3°/3° Vicinal Diols and Related Compounds
Authors: Alwedi Embarek , Zakharov Lev N. , Blakemore Paul R.
Published: September 2014

Lithiooxiranes [LiCR1(O)CR2R3, R1 = H, Me; R2/R3 = H/Ph, H/tBu, Me/Ph], generated by sulfoxide–lithium exchange from stereodefined sulfinyl epoxides (with use of PhLi or tBuLi, THF, at or below –90 °C), were employed for the stereospecific reagent‐controlled homologation of boronic esters R0–Bpin (R0 = BnCH2, allyl, cHex, Ph). Addition of TBSOTf to the intermediate ate complexes gave β‐silyloxyboronates that were converted to vicinal diol monosilyl ethers by oxidative work‐up with aq. NaOOH. The 2°/2° (4–32 %, dr > 98:2), 2°/3° (21–66 %, dr ≥ 65:35), and 3°/3° (59–68 %, dr ≥ 95:5) contiguous stereodiad‐containing compounds created in this manner were typically obtained in a highly stereocontrolled manner. In general, cis‐sulfinyl epoxides afforded anti‐like stereodiads, whereas trans‐sulfinyl epoxides afforded syn‐like stereodiads; however, as a result of its suspected configurational instability, LiCMe(O)CHPh gave anti‐like 2°/3° motifs regardless of sulfinyl epoxide stereochemistry.
Decarboxylation of a Wide Range of Amino Acids with Electrogenerated Hypobromite
Authors: Matthessen Roman , Claes Laurens , Fransaer Jan , Binnemans Koen , De Vos Dirk E.
Published: September 2014

Bromide‐assisted electrochemical decarboxylation efficiently produces valuable nitriles in high yields from a wide range of naturally occurring amino acids in a single step. Bromide salts are used as both redox mediators and supporting electrolytes in a simple one‐compartment setup. As demonstrated for lysine, the selectivity of the decarboxylation can be tuned towards nitriles, amines or amides.
Effect of taxonomic diversification of microalgae harvested from eutrophicated reservoirs on the chemical composition of biomass and effectiveness of methane fermentation
Authors: Dębowski M. , Zieliński M. , Kupczyk K. , Rokicka M. , Hajduk A.
Published: September 2014

The objective of this study was to determine the possibility of using microalgae biomass from natural water bodies as a substrate for methane fermentation and to verify the effect of taxonomic structure and other physicochemical traits of the biomass on the technological effectiveness of the process. Harvested algae was characterized by a diversified taxonomic structure and on the content of nitrogen compounds and concentration of organic compounds in biomass, that was subject to seasonal dynamics of changes. The highest technological effects of the methane fermentation process were achieved with microalgae biomass harvested in July. In this period, the predominating taxonomic group were the Cyanoprokaryota, with a significant contribution of Chlorophyta. The mean yield of biogas production reached 441.15 ± 19.03 cm3/g o.d.m., at the mean production rate of r = 98.99 cm3/day and a reaction constant of k = 0.224 1/day. The mean content of methane in biogas accounted for 68.68 ± 1.67%. The lowest technological effects linked with biogas production were determined in November. These were the periods of the vegetative season with Bacillariophyceae constituting the predominating taxonomic group. The total production of biogas accounted for 333.65 ± 18.85 cm3/g o.d.m. The methane content were at mean levels of 54.19 ± 2.31%. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 858–865, 2015
Race disparities attributed to volumetric tumor burden in patients with head and neck cancer treated with radiotherapy
Authors: Qureshi Muhammad M. , Romesser Paul B. , Ajani Abdallah , Kachnic Lisa A. , Jalisi Scharukh , Truong Minh Tam
Published: September 2014

Background

The purpose of this study was to evaluate how gross tumor volume (GTV) affects treatment outcome among different race/ethnic groups in patients with head and neck cancer receiving definitive radiotherapy (RT).

Methods

Ninety‐one patients with head and neck cancer were treated to a median RT dose of 69.96 Gy in 33 fractions. The patient's self‐reported race/ethnicity, primary tumor, and nodal GTV were obtained. Two‐year actuarial local, nodal, and distant control, and overall and disease‐free survival were calculated.

Results

The patients were categorized as white (n = 43) or non‐white (n = 48), which included 29 African Americans, 11 Hispanics, 5 Asians, and 3 others. The mean primary GTV was 21.0 cc and 39.9 cc for whites and non‐whites, respectively (p = .011). White patients reported improved overall survival of 85.4% compared to non‐whites (65.8%; p = .006). Improvements in local and nodal control and disease‐free survival rates were also observed.

Conclusion

White patients demonstrated improved treatment outcomes compared with non‐whites, which may be reflective of tumor volume. © 2015 Wiley Periodicals, Inc. Head Neck 38: 126–134, 2016
Porous PLGA microspheres tailored for dual delivery of biomolecules via layer‐by‐layer assembly
Authors: Go Dewi P. , Palmer Jason A. , Mitchell Geraldine M. , Gras Sally L. , O'Connor Andrea J.
Published: September 2014

Tissue engineering is a complex and dynamic process that requires varied biomolecular cues to promote optimal tissue growth. Consequently, the development of delivery systems capable of sequestering more than one biomolecule with controllable release profiles is a key step in the advancement of this field. This study develops multilayered polyelectrolyte films incorporating alpha‐melanocyte stimulating hormone (α‐MSH), an anti‐inflammatory molecule, and basic fibroblast growth factor (bFGF). The layers were successfully formed on macroporous poly lactic‐co‐glycolic acid microspheres produced using a combined inkjet and thermally induced phase separation technique. Release profiles could be varied by altering layer properties including the number of layers and concentrations of layering molecules. α‐MSH and bFGF were released in a sustained manner and the bioactivity of α‐MSH was shown to be preserved using an activated macrophage cell assay in vitro. The system performance was also tested in vivo subcutaneously in rats. The multilayered microspheres reduced the inflammatory response induced by a carrageenan stimulus 6 weeks after implantation compared to the non‐layered microspheres without the anti‐inflammatory and growth factors, demonstrating the potential of such multilayered constructs for the controlled delivery of bioactive molecules. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 1849–1863, 2015.
Role of integrin α2β1 in mediating osteoblastic differentiation on three‐dimensional titanium scaffolds with submicron‐scale texture
Authors: Wang Xiaokun , Schwartz Zvi , Gittens Rolando A. , Cheng Alice , Olivares‐Navarrete Rene , Chen Haifeng , Boyan Barbara D.
Published: September 2014

Hierarchical surface roughness of titanium and titanium alloy implants plays an important role in osseointegration. In vitro and in vivo studies show greater osteoblast differentiation and bone formation when implants have submicron‐scale textured surfaces. In this study, we tested the potential benefit of combining a submicron‐scale textured surface with three‐dimensional (3D) structure on osteoblast differentiation and the involvement of an integrin‐driven mechanism. 3D titanium scaffolds were made using orderly oriented titanium meshes and microroughness was added to the wire surface by acid‐etching. MG63 and human osteoblasts were seeded on 3D scaffolds and 2D surfaces with or without acid etching. At confluence, increased osteocalcin, vascular endothelial growth factor, osteoprotegerin (OPG), and alkaline phosphatase (ALP) activity were observed in MG63 and human osteoblasts on 3D scaffolds in comparison to 2D surfaces at the protein level, indicating enhanced osteoblast differentiation. To further investigate the mechanism of osteoblast‐3D scaffold interaction, the role of integrin α2β1 was examined. The results showed β1 and α2β1 integrin silencing abolished the increase in osteoblastic differentiation markers on 3D scaffolds. Time course studies showed osteoblasts matured faster in the 3D environment in the early stage of culture, while as cells proliferated, the maturation slowed down to a comparative level as 2D surfaces. After 12 days of postconfluent culture, osteoblasts on 3D scaffolds showed a second‐phase increase in ALP activity. This study shows that osteoblastic differentiation is improved on 3D scaffolds with submicron‐scale texture and is mediated by integrin α2β1. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 1907–1918, 2015.
Effect of particle size on osteoinductive potential of microstructured biphasic calcium phosphate ceramic
Authors: Wang Liao , Barbieri Davide , Zhou Hongyu , de Bruijn Joost D. , Bao Chongyun , Yuan Huipin
Published: September 2014

Material factors such as chemistry, surface microstructure and geometry have shown their influence on osteoinduction of calcium phosphate ceramics. Hereby we report that osteoinduction of a micro‐structured biphasic calcium phosphate ceramic (BCP) has a relation with the particle sizes. BCP particles with the size of 212–300 µm, 106–212 µm, 45–106 µm, and smaller than 45 µm were prepared and implanted in paraspinal muscle of dogs for 12 weeks. Histological evaluation of the explants showed abundant bone in all samples with particle size of 212–300 µm, 106–212 µm, and 45–106 µm, while no bone was seen in any sample having particle size smaller than 45 µm. Bone was formed as early as 3 weeks after implantation in implants having BCP particles bigger than 45 µm and the volume of the formed bone was similar among the implants with particles larger than 45 µm after 12 weeks implantation. The results herein show that a size limitation of microstructured calcium phosphate ceramic particles for osteoinduction. It is most likely that the particle size affect inductive bone formation via macroporous structures for body fluid infiltration, cell/tissue ingrowth and angiogenesis. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 1919–1929, 2015.
Nurse practitioner and physician assistant scope of practice in 118 acute care hospitals
Authors: Kartha Anand , Restuccia Joseph D. , Burgess James F. , Benzer Justin , Glasgow Justin , Hockenberry Jason , Mohr David C. , Kaboli Peter J.
Published: September 2014

BACKGROUND

Advanced practice providers (APPs), including nurse practitioners (NPs) and physician assistants (PAs) are cost‐effective substitutes for physicians, with similar outcomes in primary care and surgery. However, little is understood about APP roles in inpatient medicine.

OBJECTIVE

Describe APPs role in inpatient medicine.

DESIGN

Observational cross‐sectional cohort study.

SETTING

One hundred twenty‐four Veterans Health Administration (VHA) hospitals.

PARTICIPANTS

Chiefs of medicine (COMs) and nurse managers.

MEASUREMENTS

Surveys included inpatient medicine scope of practice for APPs and perceived healthcare quality. We conducted bivariate unadjusted and multivariable adjusted analyses.

RESULTS

One hundred eighteen COMs (95.2%) and 198 nurse managers (75.0%) completed surveys. Of 118 medicine services, 56 (47.5%) employed APPs; 27 (48.2%) used NPs only, 15 (26.8%) PAs only, and 14 (25.0%) used both. Full‐time equivalents for NPs was 0.5 to 7 (mean = 2.22) and PAs was 1 to 9 (mean = 2.23). Daily caseload was similar at 4 to 10 patients (mean = 6.5 patients). There were few significant differences between tasks. The presence of APPs was not associated with patient or nurse manager satisfaction. Presence of NPs was associated with greater overall inpatient and discharge coordination ratings by COMs and nurse managers, respectively; the presence of PAs was associated with lower overall inpatient coordination ratings by nurse managers.

CONCLUSIONS

NPs and PAs work on half of VHA inpatient medicine services with broad, yet similar, scopes of practice. There were few differences between their roles and perceptions of care. Given their very different background, regulation, and reimbursement, this has implications for inpatient medicine services that plan to hire NPs or PAs. Journal of Hospital Medicine 2014;9:615–620. © 2014 Society of Hospital Medicine
Posidonia oceanica (L.) based compost as substrate for potted basil production
Authors: Mininni Carlo , Grassi Francesco , Traversa Andreina , Cocozza Claudio , Parente Angelo , Miano Teodoro , Santamaria Pietro
Published: September 2014

BACKGROUND

Peat is the main component of growing media but is also a non‐renewable resource; therefore European policy strongly encourages the use of peat alternatives such as compost. Posidonia is a Mediterranean seagrass that produces very conspicuous onshore deposits that can be composted. In this study, a commercial green compost and a Posidonia residue‐based compost were tested in order to assess their potential use as substitutes or complements to peat.

RESULTS

All macro and micro‐element concentrations of the substrates were positively and significantly related to the percentage of composts in the growing media. Plant grown on peat showed higher content of P, Ca, K, Na, Cu, Mn, Zn and Fe, and a slightly higher biomass production in comparison to compost‐based growing media. In contrast, plants grown on compost‐based substrates showed lower uptake of Cd and Cr than peat.

CONCLUSION

The results indicate that both composts can be used as a complement to the peat for substrate preparation, especially at a rate of 30%. The Posidonia‐based compost showed better productive results in comparison to the green one. Basil grown on the two compost‐based media showed reduced absorption level of potentially toxic metals in comparison to peat. © 2014 Society of Chemical Industry
Photo‐Induced Anomalous Deformation of Poly(N‐Isopropylacrylamide) Gel Hybridized with an Inorganic Nanosheet Liquid Crystal Aligned by Electric Field
Authors: Inadomi Takumi , Ikeda Shogo , Okumura Yasushi , Kikuchi Hirotsugu , Miyamoto Nobuyoshi
Published: September 2014

Poly‐(N‐isopropylacrylamide) (PNIPA) hydrogel films doped with uniaxially aligned liquid crystalline (LC) nanosheets adsorbed with a dye are synthesized and its anomalous photothermal deformation is demonstrated. The alignment of the nanosheet LC at the cm‐scale is easily achieved by the application of an in‐plane or out‐of‐plane AC electric field during photo‐polymerization. A photoresponsive pattern is printable onto the gel with μm‐scale resolution by adsorption of the dye through a pattern‐holed silicone rubber. When the gel is irradiated with light, only the colored part is photothermally deformed. Interestingly, the photo‐irradiated gel shows temporal expansion along one direction followed by anisotropic shrinkage, which is an anomalous behavior for a conventional PNIPA gel.

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Subthalamic nucleus‐deep brain stimulation for early motor complications in Parkinson's disease—the EARLYSTIM trial: Early is not always better
Authors: Mestre Tiago A. , Espay Alberto J. , Marras Connie , Eckman Mark H. , Pollak Pierre , Lang Anthony E.
Published: September 2014

Subthalamic nucleus deep brain stimulation (STN‐DBS) has revolutionized the management of disabling motor complications in Parkinson's disease. The EARLYSTIM trial applied this treatment to patients who had been experiencing motor complications for less than three years. STN‐DBS significantly improved all primary and secondary outcome measures while best medical therapy failed to provide any improvement at the two‐year follow‐up time point. On face value these results strongly favor the application of STN‐DBS far earlier than is currently applied, when patients are just beginning to experience problems with motor complications. Here we review the application of early DBS and the EARLYSTIM trial from the perspectives of clinical issues, health economics and study design and patient expectation of benefit. We conclude that the most relevant issue is not when to operate but on whom and that early is not always better. © 2014 International Parkinson and Movement Disorder Society
Management of anterolateral thigh free Flap donor site defects with a continuous external tissue expander
Authors: Senchenkov Alex , Agag Richard L. , Lee Johnson , Patel Ashit , Valerio Ian L.
Published: September 2014

Anterolateral thigh (ALT) free flaps can result in donor site wounds that cannot be closed directly, requiring immediate or delayed split‐thickness skin grafting. The use of skin grafts for such wounds can impose postoperative activity restrictions and additional wound morbidity. The purpose of the study was to investigate the efficacy of continuous external tissue expander (CETE) in achieving staged direct closure of these wounds. Outcomes of 20 ALT free flap cases with flap widths up to 15 cm treated with CETE were retrospectively reviewed. Closure of the thigh wounds was achieved in 19 cases with an average expansion time of 9.6 days. The use of a CETE device was effective in achieving staged direct (tertiary) closure and avoiding skin grafting, which further decreased donor site morbidity of large ALT free flap reconstructions. © 2014 Wiley Periodicals, Inc. Microsurgery 35:290–294, 2015.
A primer on the fundamental principles of light microscopy: Optimizing magnification, resolution, and contrast
Authors: Goodwin Paul C.
Published: September 2014

The light microscope is an indispensable tool in the study of living organisms. Most biologists are familiar with microscopes, perhaps being first introduced to the wonders of the world of small things at a very early age. Yet, few fully comprehend the nature of microscopy and the basis of its utility. This review (re)‐introduces the concepts of magnification, resolution, and contrast, and explores how they are intimately related and necessary for effective microscopy. Mol. Reprod. Dev. 82: 502–507, 2015. © 2014 Wiley Periodicals, Inc.
Assessing tumor cytoarchitecture using multiecho DSC‐MRI derived measures of the transverse relaxivity at tracer equilibrium (TRATE)
Authors: Semmineh Natenael B. , Xu Junzhong , Skinner Jack T. , Xie Jingping , Li Hua , Ayers Gregory , Quarles C. Chad
Published: September 2014

Purpose

In brain tumor dynamic susceptibility contrast (DSC)‐MRI studies, multiecho acquisition methods are used to quantify the dynamic changes in T1 and T2* that occur when contrast agent (CA) extravasates. Such methods also enable the estimation of the effective tissue CA transverse relaxivity. The goal of this study was to evaluate the sensitivity of the transverse relaxivity at tracer equilibrium (TRATE) to tumor cytoarchitecture.

Methods

Computational and in vitro studies were used to evaluate the biophysical basis of TRATE. In 9L, C6, and human brain tumors, TRATE, the apparent diffusion coefficient (ADC), the CA transfer constant (Ktrans), the extravascular extracellular volume fraction (ve), and histological data were compared.

Results

Simulations and in vitro results indicate that TRATE is highly sensitive to variations in cellular properties such as cell size and density. The histologic cell density and TRATE values were significantly higher in 9L tumors as compared to C6 tumors. In animal and human tumors, a voxel‐wise comparison of TRATE with ADC, ve, and Ktrans maps showed low spatial correlation.

Conclusion

The assessment of TRATE is clinically feasible and its sensitivity to tissue cytoarchitectural features not present in other imaging methods indicate that it could potentially serve as a unique structural signature or “trait” of cancer. Magn Reson Med 74:772–784, 2015. © 2014 Wiley Periodicals, Inc.
Quantification of myocardial blood flow using non–ECG‐triggered MR imaging
Authors: Chen David , Sharif Behzad , Dharmakumar Rohan , Thomson Louise E.J. , Bairey Merz C. Noel , Berman Daniel S. , Li Debiao
Published: September 2014

Purpose

MR myocardial perfusion imaging is dependent on reliable electrocardiogram (ECG) triggering for accurate measurement of myocardial blood flow (MBF). A non–ECG‐triggered method for quantitative first‐pass imaging may improve clinical feasibility in patients with poor ECG signal. The purpose of this study is to evaluate the feasibility of a non–ECG‐triggered method for myocardial perfusion imaging in a single slice.

Methods

The proposed non–ECG‐triggered technique uses a saturation‐recovery magnetization preparation and golden‐angle radial acquisition for integrated arterial input function (AIF) measurement. Image based self‐gating with a temporal resolution of 42.6 ms is used to generate a first‐pass image series with consistent cardiac phase. The AIF is measured using beat‐by‐beat T1 estimation of the ventricular blood pool. The proposed technique was performed on 14 healthy volunteers and compared against a conventional ECG‐triggered dual‐bolus acquisition.

Results

The proposed method produced MBF with no significant difference compared with ECG‐triggered technique (mean of 0.63 ± 0.22 mL/min/g to 0.73 ± 0.21 mL/min/g).

Conclusion

We have developed a non–ECG‐triggered perfusion imaging method with T1 based measurement of the AIF in a single slice. In this preliminary study, our results demonstrate that MBF measured using the proposed method is comparable to the conventional ECG‐triggered method. Magn Reson Med 74:765–771, 2015. © 2014 Wiley Periodicals, Inc.
A three‐level linearized compact difference scheme for the Ginzburg–Landau equation
Authors: Hao Zhao‐Peng , Sun Zhi‐Zhong , Cao Wan‐Rong
Published: September 2014

A high‐order finite difference method for the two‐dimensional complex Ginzburg–Landau equation is considered. It is proved that the proposed difference scheme is uniquely solvable and unconditionally convergent. The convergent order in maximum norm is two in temporal direction and four in spatial direction. In addition, an efficient alternating direction implicit scheme is proposed. Some numerical examples are given to confirm the theoretical results. © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 31: 876–899, 2015
Best practices in noncommercial radio fundraising: a practitioner perspective
Authors: Bentley Joshua M.
Published: September 2014

This study uses in‐depth qualitative interviews with radio professionals in the United States to identify best practices for noncommercial radio fundraising. Most noncommercial stations use on‐air pledge drives to solicit donations from listeners, and this is a major source of revenue for these stations. The interview data are analyzed using the constant comparative method. Findings indicate that radio professionals use a variety of fundraising appeals to reach listeners with different motivations for donating. These fundraising appeals have three dimensions: altruism/self‐interest, rational/emotional, and reinforcement/trigger. The data also indicate that noncommercial stations try to foster relationships with their listeners and donors. These relationships are managed through direct communication and through mass communication, which produces parasocial interaction.

Copyright © 2014 John Wiley & Sons, Ltd.
Normal mandibular growth and diagnosis of micrognathia at prenatal MRI
Authors: Nemec Ursula , Nemec Stefan F. , Brugger Peter C. , Weber Michael , Bartsch Bernhard , Bettelheim Dieter , Gruber Michael , Prayer Daniela
Published: September 2014

Objective

The aim of this article is to present reference data for fetal mandibular growth on magnetic resonance imaging, enabling the diagnosis of micrognathia.

Methods

Retrospectively, on 355 magnetic resonance scans of apparently facially normal fetuses [gestational age (GA), 20–36 weeks], mandibular anterior–posterior diameter (APD = mandibular size), inferior facial angle (IFA = mandibular position), and jaw index (APD normalized to biparietal diameter) were correlated with GA by Pearson correlation. APD–age relationship was modeled. A receding chin was subjectively determined. Ten fetuses with mandibular anomalies were compared with normal fetuses.

Results

For GA, APD showed high correlation (r = 0.850;P < 0.001), IFA (r = 0.086;P = 0.119) no correlation, and jaw index (r = −0.139;P = 0.018) weak correlation. APD–age relationship was expressed by the following: APD = 0.281 + 0.989 * GA (r2 = 0.723). A receding chin was identified in 7/10 abnormal fetuses. APD, IFA, and jaw index of abnormal and normal fetuses were significantly different (P < 0.001). In 10/10 abnormal fetuses, IFA was <50.0°; in 7/10, jaw index was less than the fifth percentile (micrognathia); in 3/10, jaw index was at low normal range (retrognathia).

Conclusions

Subjective identification of micrognathia may be limited. Reference data provide quantitative evaluation of mandibular size and position. An IFA <50° reflects micrognathia or retrognathia; a jaw index less than the fifth percentile suggests micrognathia. © 2014 John Wiley & Sons, Ltd.
Anisotropic Imprint of Amorphization and Phase Separation in Manganite Thin Films via Laser Interference Irradiation
Authors: Ding Junfeng , Lin Zhipeng , Wu Jianchun , Dong Zhili , Wu Tom
Published: September 2014

Materials with mesoscopic structural and electronic phase separation, either inherent from synthesis or created via external means, are known to exhibit functionalities absent in the homogeneous counterparts. One of the most notable examples is the colossal magnetoresistance discovered in mixed‐valence manganites, where the coexistence of nano‐ to micrometer‐sized phase‐separated domains dictates the magnetotransport. However, it remains challenging to pattern and process such materials into predesigned structures and devices. In this work, a direct laser interference irradiation (LII) method is employed to produce periodic stripes in thin films of a prototypical phase‐separated manganite Pr0.65(Ca0.75Sr0.25)0.35MnO3 (PCSMO). LII induces selective structural amorphization within the crystalline PCSMO matrix, forming arrays with dimensions commensurate with the laser wavelength. Furthermore, because the length scale of LII modification is compatible to that of phase separation in PCSMO, three orders of magnitude of increase in magnetoresistance and significant in‐plane transport anisotropy are observed in treated PCSMO thin films. Our results show that LII is a rapid, cost‐effective and contamination‐free technique to tailor and improve the physical properties of manganite thin films, and it is promising to be generalized to other functional materials.