bluuebunny/crossref_metadata_2025_split huggingface dataset:
Debittering of black dry‐salted olives
Authors: Ramírez Eva , García‐García Pedro , de Castro Antonio , Romero Concepción , Brenes Manuel 
Published: August 2013

The objective of this work was to investigate the debittering process of dry‐salted olives. Fruits of the Manzanilla cultivar were put into layers of coarse salt and their physicochemical and microbiological parameters were assessed during the dehydration step. A correlation between the content in salt of the olive juice and the ratio salt/olives was found: the lower the ratio, the higher the concentration of salt in the dry‐salted olives. The population of lactic acid bacteria on the olive surface was not significant while yeasts, molds and Enterobacteriaceae were the predominant microbiota. In addition, the analyses of phenolic compounds in the olive flesh revealed that most of them disappeared during the dehydration process, in particular the bitter glucoside oleuropein. Likewise, freshly harvested olives were pasteurized and submitted for dehydration but in this case the degradation of oleuropein and the rest of polyphenols did not occur. All these findings suggest that olive debitter during the dry‐salting process due to the enzymatic oxidation of oleuropein in the olive flesh resulting in no leaching of the phenolic glucoside in the generated brine.Practical applications: This is the first report focusing on the debittering process of dry‐salted olives. An enzymatic pathway for oleuropein degradation has been found, and it opens up the possibility to optimize this reaction taking into consideration the variables involved such as phenolic compounds, oxidative enzyme, and oxygen. The ratio salt/olives must be as low as 0.4 to reach a high concentration of salt in the juice of dehydrated olives needed for the chemical and microbial stability of the product.
Cloning and molecular characterization of a class A lysophosphatidate acyltransferase gene (EpLPAT2) from Echium (Boraginaceae)
Authors: Mañas‐Fernández Aurora , Arroyo‐Caro José María , Alonso Diego López , García‐Maroto Federico 
Published: August 2013

Lysophosphatidate acyltransferase (LPAT) catalyzes the incorporation of acyl groups into the sn‐2 position of lysophosphatidate (LPA) rendering phosphatidic acid (PA), a key intermediary in the synthesis of phospholipids (PLs) and triacylglycerols (TAGs). It is considered as a highly selective activity and a strong determinant of fatty acid (FA) composition of membranes and reserve glycerolipids in diverse plants. In this work, we have cloned a gene encoding the microsomal class A LPAT (LPAT2) from Echium pitardii (Boraginaceae), a species that accumulates high levels of long chain polyunsaturated FAs (LCPUFAs) in the seed oil. The Echium gene (EpLPAT2) is ubiquitously expressed in diverse organs of the plant, although the transcript level is increased in those tissues with a higher α‐linolenic acid (18:3n3) content. Functionality of EpLPAT2 was proven by complementation of a LPAT defective mutant of Escherichia coli (plsC), and by a biochemical assay of the expressed enzyme in membrane extracts. Acyl‐CoA specificity recorded for EpLPAT2, using oleoyl‐LPA (18:1‐LPA) as acyl‐acceptor, shows a clear preference for unsaturated acyl substrates, with 18:3n3‐CoA being used at similarly high rates as 18:1‐CoA. Overexpression of EpLPAT2 in yeast increased FA content, and modified the FA profile of membrane lipids in agreement to the in vitro specificity.Practical applications: One can envisage that overexpression of EpLPAT2 in transgenic plants, either alone or in combination with other genes could increase seed oil content. Moreover, the observed specificity of EpLPAT2 might be a useful characteristic in tailoring of a plant engineered for LCPUFA‐enriched oil.
Emulsion copolymerization of styrene and acrylated methyl oleate
Authors: Jensen Alan T. , Sayer Claudia , Araújo Pedro H. H. , Machado Fabricio 
Published: August 2013

In this work, the emulsion copolymerization of styrene and acrylated methyl oleate (AMO), a monomer derived from oleic acid (OA), has been evaluated. Reactions exhibiting high monomers conversions were successfully performed, leading to the formation of very stable polymer lattices, whose average particle size is kept unchanged for relatively high storage times. The average molar masses determined by gel permeation chromatography showed to be very dependent on the amount of AMO in the reaction medium, presenting experimental values within the range from 280 000 to 39 000 g mol−1 with molar mass dispersity ranging from 4 to 2 when the AMO fraction in the reaction medium was increased to 40 wt%. The nucleation rate was affected by AMO in such way that an increase in AMO concentration must be accompanied by an increase in initiator concentration, which leads to the reduction of the average molar masses of the copolymer. The thermal analyses of the polymer materials showed that the glass transition temperature decreased with increasing amount of AMO in the copolymer chains.Practical applications: The use of vegetable oils and their derivatives as precursor monomers in polymerization reactions has increased each day due to their renewable origin. Among them, OA deserves special attention due to the high availability and ease of chemical modification, mainly when the double bounds are considered. Results showed that AMO could be incorporated at high ratios in emulsion polymerization reducing the glass transition temperatures of the copolymer. The polymer lattices also showed good storage stability.
Synthesis and Electrochemical Properties of Carbocyclic and Heterocyclic Diazulenylethenes
Authors: Dragu Eugenia Andreea , Nica Simona , Tecuceanu Victorita , Bala Daniela , Mihailciuc Constantin , Hanganu Anamaria , Razus Alexandru C. 
Published: August 2013

AbstractAn efficient two‐step method was developed for the synthesis of 1,2‐di(azulen‐1‐yl)ethenes 15–17, having the double bond included in a five‐membered carbocyclic or heterocyclic ring. The method involves preparation of the appropriate diketone precursors through Vilsmeier–Haack or Friedel–Crafts reactions, followed by their McMurry cyclization. Alkenes 16 and 17 were quantitatively converted into the corresponding dehydro derivatives 24 and 25, respectively, by oxidation with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ). The electrochemical properties of compounds 15–17, 24 and 25 were examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV), and the relationship between their structure and electrochemical behavior was established.
Effects of Antioxidants on the Cetane number, Viscosity, Oxidation Stability, and Thermal Properties of Biodiesel Produced from Nonedible Oils
Authors: Kivevele Thomas T. , Huan Zhongjie 
Published: August 2013

AbstractPoor oxidation stability of biodiesel is the central problem associated with its commercial acceptance. To enhance the practical feasibility of biodiesel, antioxidants are added to increase its storage stability. It is quite possible that these additives may affect other basic fuel properties of biodiesel. Therefore, the present study investigated the effects of antioxidants on the basic fuel properties of biodiesel produced from nonedible oils of African origin (Moringa oleifera, Jatropha curcus, and Croton megalocarpus). Four antioxidants: 1,2,3‐trihydroxybenzene (pyrogallol, PY), 3,4,5‐trihydroxybenzoic acid (propyl gallate, PG), 2‐tert‐butyl‐4‐methoxyphenol (butylated hydroxyanisole, BHA) and 2,6‐di‐tert‐butyl‐4‐methylphenol (Butylated Hydroxy Toluene, BHT) were investigated for their effectiveness in oxidation stability. The results showed that PY and PG were more effective than BHA and BHT. The most effective antioxidant (PY in this study) was was studied further for its effects on other basic fuel properties of biodiesels such as kinematic viscosity, cetane number, and thermal properties. It was observed that the kinematic viscosity was reduced at lower concentrations of antioxidant additives (500 ppm) and slightly increased at high concentrations (1000 ppm) but lower than that of pure biodiesel. The cetane number was slightly increased at both 500 and 1000 ppm of PY antioxidant content. The effects of the antioxidant on the thermal properties were not clearly observed. Therefore, it can be concluded that adding antioxidants to biodiesel lengthens increases the storage stability and also improves the kinematic viscosity, thermal properties, and cetane number as an added advantage.
LQR control with frequency‐dependent scheduled gain for a semi‐active floor isolation system
Authors: Shi Yundong , Becker Tracy C. , Furukawa Sachi , Sato Eiji , Nakashima Masayoshi 
Published: August 2013

SUMMARYFloor isolation is an alternative to base isolation for protecting a specific group of equipment installed on a single floor or room in a fixed‐base structure. The acceleration of the isolated floor should be mitigated to protect the equipment, and the displacement needs to be suppressed, especially under long‐period motions, to save more space for the floor to place equipment. To design floor isolation systems that reduce acceleration and displacement for both short‐period and long‐period motions, semi‐active control with a newly proposed method using the linear quadratic regulator (LQR) control with frequency‐dependent scheduled gain (LQRSG) is adopted. The LQRSG method is developed to account for the frequency characteristics of the input motion. It updates the control gain calculated by the LQR control based on the relationship between the control gain and dominant frequency of the input motion. The dominant frequency is detected in real time using a window method. To verify the effectiveness of the LQRSG method, a series of shake table tests is performed for a semi‐active floor isolation system with rolling pendulum isolators and a magnetic‐rheological damper. The test results show that the LQRSG method is significantly more effective than the LQR control over a range of short‐period and long‐period motions. Copyright © 2013 John Wiley & Sons, Ltd.
Energy and spectral efficiencies trade‐off with filter optimisation in multiple access interference‐aware networks
Authors: Souza Álvaro R.C. , Abrão Taufik , Sampaio Lucas H. , Jeszensky Paul Jean E. , Pérez‐Romero Jordi , Casadevall Ferran 
Published: August 2013

AbstractIn this contribution, the optimised deployment of both spectrum and energy resources scarcely available in the mobile multiple access systems has been analysed, with special attention to the impact of the filter design on the energy efficiency (EE) of code division multiple access networks. Putting into perspective two conflicting metrics, namely throughput maximisation and power consumption minimisation, the distributed EE utility function is formulated. We also show that the best EE versus spectral efficiency trade‐off is achievable when each node allocates exactly the power necessary to attain the maximum EE. In order to demonstrate the validity of our analysis, a low‐complexity energy‐spectral‐efficient algorithm based on distributed instantaneous signal‐to‐interference‐plus‐noise ratio level is developed, and the impact of single and multi‐user detection filters on the EE–spectral efficiency trade‐off is extensively analysed by numerical simulation. Copyright © 2013 John Wiley & Sons, Ltd.
Bis(phosphonate)‐Building Blocks Modified with Fluorescent Dyes
Authors: David Tomáš , Kotek Jan , Kubíček Vojtěch , Tošner Zdeněk , Hermann Petr , Lukeš Ivan 
Published: August 2013

ABSTRACTPreparation of two benzylic bis(phosphonic acids) modified with primary amine or carboxylic acid groups on the benzene ring is described. These compounds were prepared and characterized in the form of both bis(phosphonate) tetraesters and corresponding free acids. The phosphonic acid esters are suitable for further derivation, mainly for conjugation through the amide bond. Mild conversion of the bis(phosphonate) esters to free acids using trimethylsilylbromide allowed to work with functional groups sensitive to conditions of acidic and/or alkaline hydrolysis. Three bis(phosphonate)‐containing fluorescent probes were prepared from the building blocks, utilizing amide and sulfamide bonds as spacers. Dyes containing the dansyl group, rhodamine B, and fluorescein were chosen due to their common availability and low cost. The prepared bis(phosphonate)‐building blocks and modified fluorescent probes were used for adsorption studies with hydroxyapatite, the commonly used model of bone tissue. Sorption ability of the prepared bis(phosphonate) compounds was similar to that of pamidronate.
Polystyrene‐Gallium Trichloride Complex: A Mild, Highly Efficient, and Recyclable Polymeric Lewis Acid Catalyst for Chemoselective Silylation of Alcohols and Phenols with Hexamethyldisilazane
Authors: Rahmatpour Ali , Vakili Ali , Azizian Setare 
Published: August 2013

ABSTRACTPolystyrene‐supported gallium trichloride (PS/GaCl3) as a highly active and reusable heterogeneous Lewis acid effectively activates hexamethyldisilazane (HMDS) for the efficient silylation of alcohols and phenols at room temperature. In this heterogeneous catalytic system, primary, secondary, and tertiary alcohols as well as phenols were converted to their corresponding trimethylsilyl ethers with short reaction times and high yields under mild reaction conditions. The heterogenized catalyst is of high reusability and stability in the silylation reactions and was recovered several times with negligible loss in its activity or a negligible catalyst leaching, and also there is no need for regeneration. It is noteworthy that this method can be used for chemoselective silylation of different alcohols and phenols with high yields.
Cytocompatibility assessment of chemical surface treatments for phosphate glass to improve adhesion between glass and polyester
Authors: S. Hasan M. , Ahmed I. , Parsons A. J. , Walker G. S. , Scotchford C. A. 
Published: August 2013

Fully resorbable phosphate glass fiber reinforced polymer composites have shown real potential for replacing some of the existing metallic bone fracture fixation devices. However, some of these composites have not provided suitable mechanical strength profiles over the required healing period for bone. Typically, it has been seen that these composites can lose up to 50% or more of their strength within the first week of degradation. Functionalizing the glass surface to promote polymer adhesion or to introduce hydrophobicity at the glass surface could potentially introduce control over the mechanical properties of the composite and their retention. In this study eight chemical agents namely, Glycerol 2‐phosphate disodium salt; 3‐phosphonopropionic acid; 3‐aminopropyltriethoxy silane; etidronic acid; hexamethylene diisocyanate; sorbitol/sodium ended PLA oligomers and amino phosphonic acid, were selected to functionalise the bulk phosphate glass surface. Selected chemical agents had one functional group (—OH or O C N) to react with the glass and another functionality (either —OH, NH2,or Na) to react with the polymer matrix and/or produce hydrophobicity at the fiber surface. Bulk phosphate glass surface‐treated with the above agents were assessed for the cytotoxicity of degradation products cell‐material interaction in short‐ and long‐term direct cytocompatibility studies. Results obtained from these cytocompatibility studies (using human osteosarcoma (MG63) and primary human osteoblast cell lines) revealed no cytotoxicity from the degradation products and a response comparable to controls in terms of cell functions (attachment, viability, metabolic activity, proliferation, and differentiation) and morphology. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 3301–3310, 2013.
Insulin Resistance and Bone Strength: Findings From the Study of Midlife in the United States
Authors: Srikanthan Preethi , Crandall Carolyn J , Miller-Martinez Dana , Seeman Teresa E , Greendale Gail A , Binkley Neil , Karlamangla Arun S 
Published: August 2013

ABSTRACT

Although several studies have noted increased fracture risk in individuals with type 2 diabetes mellitus (T2DM), the pathophysiologic mechanisms underlying this association are not known. We hypothesize that insulin resistance (the key pathology in T2DM) negatively influences bone remodeling and leads to reduced bone strength. Data for this study came from 717 participants in the Biomarker Project of the Midlife in the United States Study (MIDUS II). The homeostasis model assessment of insulin resistance (HOMA-IR) was calculated from fasting morning blood glucose and insulin levels. Projected 2D (areal) bone mineral density (BMD) was measured in the lumbar spine and left hip using dual-energy X-ray absorptiometry (DXA). Femoral neck axis length and width were measured from the hip DXA scans, and combined with BMD and body weight and height to create composite indices of femoral neck strength relative to load in three different failure modes: compression, bending, and impact. We used multiple linear regressions to examine the relationship between HOMA-IR and bone strength, adjusted for age, gender, race/ethnicity, menopausal transition stage (in women), and study site. Greater HOMA-IR was associated with lower values of all three composite indices of femoral neck strength relative to load, but was not associated with BMD in the femoral neck. Every doubling of HOMA-IR was associated with a 0.34 to 0.40 SD decrement in the strength indices (p &lt; 0.001). On their own, higher levels of fasting insulin (but not of glucose) were independently associated with lower bone strength. Our study confirms that greater insulin resistance is related to lower femoral neck strength relative to load. Further, we note that hyperinsulinemia, rather than hyperglycemia, underlies this relationship. Although cross-sectional associations do not prove causality, our findings do suggest that insulin resistance and in particular, hyperinsulinemia, may negatively affect bone strength relative to load. © 2014 American Society for Bone and Mineral Research.
Roles of Parathyroid Hormone (PTH) Receptor and Reactive Oxygen Species in Hyperlipidemia‐Induced PTH Resistance in Preosteoblasts
Authors: Li Xin , Garcia Jamie , Lu Jinxiu , Iriana Sidney , Kalajzic Ivo , Rowe David , Demer Linda L. , Tintut Yin 
Published: August 2013

ABSTRACTBioactive lipids initiate inflammatory reactions leading to pathogenesis of atherosclerosis. Evidence shows that they also contribute to bone loss by inhibiting parathyroid hormone receptor (PTH1R) expression and differentiation of osteoblasts. We previously demonstrated that bone anabolic effects of PTH(1–34) are blunted in hyperlipidemic mice and that these PTH effects are restored by antioxidants. However, it is not clear which osteoblastic cell developmental stage is targeted by bioactive lipids. To investigate the effects of hyperlipidemia at the cellular level, hyperlipidemic Ldlr−/− mice were bred with Col3.6GFPtpz mice, in which preosteoblasts/osteoblasts carry a topaz fluorescent label, and with Col2.3GFPcyan mice, in which more mature osteoblasts/osteocytes carry a cyan fluorescent label. Histological analyses of trabecular bone surfaces in femoral as well as calvarial bones showed that intermittent PTH(1–34) increased fluorescence intensity in WT‐Tpz mice, but not in Tpz‐Ldlr−/− mice. In contrast, PTH(1–34) did not alter fluorescence intensity in femoral cortical envelopes of either WT‐Cyan or Ldlr−/−‐Cyan mice. To test the mechanism of PTH1R downregulation, preosteoblastic MC3T3‐E1 cells were treated with bioactive lipids and the antioxidant Trolox. Results showed that inhibitory effects of PTH1R levels by bioactive lipids were rescued by pretreatment with Trolox. The inhibitory effects on expression of PTH1R as well as on PTH‐induced osteoblastic genes were mimicked by xanthine/xanthine oxidase, a known generator of reactive oxygen species. These findings suggest an important role of the preosteoblastic development stage as the target and downregulation of PTH receptor expression mediated by intracellular oxidant stress as a mechanism in hyperlipidemia‐induced PTH resistance. J. Cell. Biochem. 115: 179–188, 2014. © 2013 Wiley Periodicals, Inc.
Role of SPARC in Bone Remodeling and Cancer‐Related Bone Metastasis
Authors: Ribeiro Nilza , Sousa Susana R. , Brekken Rolf A. , Monteiro Fernado J. 
Published: August 2013

ABSTRACTThere is a growing socioeconomic recognition that clinical bone diseases such as bone infections, bone tumors and osteoporotic bone loss mainly associated with ageing, are major issues in today's society. SPARC (secreted protein, acidic and rich in cysteine), a matricellular glycoprotein, may be a promising therapeutic target for preventing or treating bone‐related diseases. In fact, SPARC is associated with tissue remodeling, repair, development, cell turnover, bone mineralization and may also participate in growth and progression of tumors, namely cancer‐related bone metastasis. Yet, the function of SPARC in such biological processes is poorly understood and controversial. The main objective of this work is to review the current knowledge related to the activity of SPARC in bone remodeling, tumorigenesis, and bone metastasis. Progress in understanding SPARC biology may provide novel strategies for bone regeneration and the development of anti‐angiogenic, anti‐proliferative, or counter‐adhesive treatments specifically against bone metastasis. J. Cell. Biochem. 115: 17–26, 2014. © 2013 Wiley Periodicals, Inc.
An evaluation of author productivity in international radiography journals 2004–2011
Authors: Snaith Beverly A. 
Published: August 2013

AbstractIntroductionRadiography, the allied health profession, has changed beyond recognition over the last century; however, in academic terms radiography is a relatively young profession. It is therefore still establishing its professional knowledge base. This article uses peer‐review author productivity distribution to evaluate its scholarly maturity.MethodsFour peer‐reviewed journals in medical radiation sciences were examined over an 8‐year period (2004–2011) and author productivity was compared to Lotka's law. Further analysis of the most prolific authors provided an evaluation of their characteristics.ResultsThe 1306 unique authors contributed 835 articles during the study period. Of these, 1012 (77.5%) contributed only one article to the journals studied, with an inverse power relationship of author productivity. At the 0.1 level of significance, radiography does not fit Lotka's law (n = −2.334; c = 0.712; Dmax = 0.0627; Critical threshold = 0.0337). There was a significant correlation between the most prolific authors and collaboration (P = 0.002), although variation was noted in author discipline and location.ConclusionsThe results of this study add to the discussion of radiography scholarship and demonstrate that the radiography authors have similar productivity distribution to other professions, but do not follow Lotka's law.
μ‐Raman spectroscopy of prehistoric paintings from the Abrigo Remacha rock shelter (Villaseca, Segovia, Spain)
Authors: Iriarte Mercedes , Hernanz Antonio , Ruiz‐López Juan F. , Martín Santiago 
Published: August 2013

AbstractThe composition of the materials present in prehistoric paintings discovered on the walls of the Abrigo Remacha rock shelter (Villaseca, Segovia, Spain) has been characterised by micro‐Raman spectroscopy. In addition, scanning electron microscopy and energy dispersive X‐ray microanalysis have been used as auxiliary techniques. The results show that haematite (α‐Fe2O3) is the main component of the red pigment. Amorphous carbon and paracoquimbite (Fe2(SO4)3.9H2O) have been detected in the bluish black pigment used in a significant bi‐colour pictograph. This is the first time that this mineral has been discovered in a prehistoric painting. Accretions of whewellite and weddellite form crusts covering most of the painting panel. Different carbonates are the main components of the rocky substrate. The detection of gypsum on the surface of the panel is associated to the flaking process that is affecting the painting panel. Copyright © 2013 John Wiley & Sons, Ltd.