bluuebunny/crossref_metadata_2025 huggingface dataset:
The comparison of properties of the oil and kernels of various hazelnuts from Germany and Turkey
Authors: Matthäus Bertrand , Özcan Mehmet Musa
Published: February 2012

The oil yields of hazelnut kernels collected from Germany (Münster) and Turkey range from 8.1 to 64.1%. The main fatty acids in hazelnut kernel oils are oleic (76.3–82.6%), linoleic (6.5–14.0%), and palmitic (5.7–6.5%). The hazelnut kernel oils contained an appreciable amount of α‐tocopherol (19.9–63.9 mg/100 g), with a mean value of 40.02 mg/kg, and γ‐tocopherol (1.3–15.5 mg/100 g), with a mean value of 4.84. α‐Tocopherol was the predominant tocopherol in all hazelnut kernels. The major sterols were β‐sitosterol, ranging from 78.13 to 82.56 mg/kg; campesterol, ranging from 4.79 to 7.42 mg/kg; and δ5‐avanasterol, ranging from 1.26 to 5.24 mg/kg. The highest minerals were K and P followed by Ca, Mg, Na, and Zn. P contents of all samples were established between 2029.90 and 4376.66 ppm. The results may also be useful for the evaluation of nutritional information. As a result, the present study showed that the kernels of hazelnut are a potential source of valuable oil which might be used for food and non‐food applications. In addition, hazelnut kernel oil has a high nutritive value and can be recommended for processing of healthy food products.
Synthesis and Two‐Photon Properties of Small Dendritic Chromophores with Symmetrical and Unsymmetrical Substituted Skeletons
Authors: Lin Tzu‐Chau , Lee Ying‐Hsuan , Hu Chia‐Ling , Li Yu‐Kai , Huang Yu‐Jhen
Published: February 2012

A set of novel multi‐branched chromophores consisting of two groups of fluorene/oxadiazole‐based analogues with generic skeletons of donor‐π‐acceptor (unsymmetrical) and donor‐π‐acceptor‐π‐donor (symmetrical) type has been synthesized and shown to display strong and broadly dispersed two‐photon absorptivities in the near infrared (NIR) region on irradiation with femtosecond laser pulses. It is also demonstrated that structural parameters such as the number of donor units attached and the substitution pattern are closely connected to the molecular two‐photon activities of these model compounds.
Combating channel eviction triggering denial‐of‐service attacks in cognitive radio networks
Authors: Sodagari Shabnam , Attar Alireza , Leung Victor C.M. , Bilén Sven G.
Published: February 2012

We focus on a specific class of denial‐of‐service (DoS) attacks that is executed through Channel Eviction Triggering (CET), whereby adversary nodes unduly invoke mechanisms inherent in a cognitive radio (CR) network (CRN) operation to protect the licensed users and thus disrupt secondary access to the otherwise idle licensed bands. Skewing the spectrum sensing decision of CRN through sensing misreports is a manifestation of CET attacks. Whereas most studies in the literature focus on making the cooperative sensing more robust against such sensing misreports, we tackle the problem from the novel perspective of incentive alleviation. We distinguish two classes of such DoS attacks, which we refer to as CET and CET‐jamming attacks. In the former case, the incentive of adversary CRs is to remove the competition of truthful CRs in accessing the licensed spectral ranges. The latter class of DoS attack deals with scenarios in which the adversary nodes are mainly interested in denying the chances of communication of CRN over primary bands and as such their incentive cannot be modelled by the same utility maximisation model as truthful CRs. We propose a solution for each class of attacks, and our numerical results verify the effectiveness of the proposed CET defence scheme in both cases. Copyright © 2012 John Wiley & Sons, Ltd.
An Objective Approach to Defining Earthwork Geometries Using Subdecimeter Digital Elevation Models
Authors: O'Neal Michael A.
Published: February 2012

Alligator Mound, a ca. 800‐year‐old effigy earthwork located in central Ohio, lies within a 2000 m2 area on the edge of a steeply sloping bluff. This earthwork, with a maximum local relief of approximately 1.5 m, blends into the underlying natural topography, complicating the extraction of measurements of its geometry. To overcome this limitation, a 5 cm × 5 cm gridded digital elevation model (DEM) of Alligator Mound was developed from 2,534,774 elevation points collected from 11 survey locations using a terrestrial light detection and ranging system. This subdecimeter DEM and a derivative local relief model (LRM) capture the subtle topography at this site so that the natural landscape can be objectively filtered from the earthwork. The resulting geometric data (i.e., perimeter, lengths, area, and volume) are compared with subjective historical depictions of this partially denuded earthwork. The results show the value of subdecimeter scale DEMs and LRMs for characterizing subtle features constructed on complex underlying topographies, and for monitoring and/or mitigating long‐term natural and anthropogenic earthwork degradation.
P2X4 receptor channels form large noncytolytic pores in resting and activated microglia
Authors: Bernier Louis‐Philippe , Ase Ariel R. , Boué‐Grabot Éric , Séguéla Philippe
Published: February 2012

P2X4 ATP‐gated cation channels have been shown to contribute to the microglial component of central sensitization, making their functional regulation a key element in chronic pain pathologies. Here we show that prolonged activation of native P2X4 receptor channels by ATP induces opening of a pore permeable to NMDG+ and large fluorescent dyes in BV‐2 microglial cells and primary murine microglia. This intrinsic pore formation mechanism is potentiated by LPS treatment, known to upregulate P2X4 expression in microglial cells and to mimic the microglial activation observed in neuropathic pain states. Sustained activation of the P2X7 channel subtype, also expressed in microglia, induces a pore formation that requires pannexin hemichannels and leads to plasma membrane blebbing and cytotoxicity. In contrast, P2X4 pore formation is unaffected by the pannexin blocker carbenoxolone, does not induce cytoskeletal rearrangements and does not lead to cell death. Furthermore, we show that P2X4 pore dilation is modulated by phosphoinositides (PIPn) levels as it is inhibited by wortmannin, a blocker of PIPn synthesis, suggesting possible regulation by phospholipase C‐coupled pathways. Nonlethal P2X4 pore dilation could play a role in neuropathic pain by allowing the flux of large organic molecules in microglia. Different outcomes of P2X4 and P2X7 membrane permeabilization point to subtype‐specific microglial responses to ATP in normal and pathological neuro‐immune crosstalks. © 2012 Wiley Periodicals, Inc.
The magnitude of the antigen‐specific T cell response is separated from the severity of spinal cord histopathology in remitting‐relapsing experimental autoimmune encephalomyelitis
Authors: Batoulis Helena , Uhl Martin , Addicks Klaus , Lehmann Paul V. , Kuerten Stefanie
Published: February 2012

Multiple sclerosis (MS) is an autoimmune disorder of the central nervous system. The remitting‐relapsing experimental autoimmune encephalomyelitis (EAE) in the SJL mouse strain is a common animal model for MS and similar to the human disease it is considered to be T helper cell mediated. Besides interferon‐γ secreting TH1 cells in particular the TH17 subset is believed to be highly pathogenic. Spreading of the TH1 and TH17 response to newly emerging determinants has been used to explain clinical disease relapse, but if the magnitude of the TH1/TH17 response is linked to clinical relapse severity has remained unresolved. Here, we assessed clinical EAE severity, the extent of spinal cord histopathology and the magnitude of the antigen‐specific T helper cell and autoantibody response in proteolipid protein peptide 139–151 (PLP:139–151)‐immunized SJL mice in clinical remission and relapse. We demonstrate that spinal cord histopathology comprised inflammation, demyelination as well as axonal loss and correlated well with clinical disease severity. Although the degree of spinal cord histopathology and clinical severity was separated from the PLP:139–151‐specific TH1/TH17 cell and antibody response, it was linked to the number of infiltrating macrophages and activated microglia. In particular, there was a correlation between their secretion product interleukin‐1β and the degree of axonal loss. Although CD4+ T cells seem to be mainly involved in disease initiation, we suggest that it is the downstream activation of the innate immune response that defines the magnitude of the disease outcome. © 2012 Wiley Periodicals, Inc.
Disruption of Staphylococcus epidermidis biofilm formation using a targeted cationic peptide
Authors: Hofmann Christopher M. , Bednar Kyle J. , Anderson James M. , Marchant Roger E.
Published: February 2012

This study reports the use of a targeted cationic peptide with the ability to disrupt Staphylococcus epidermidis biofilm formation. Complications due to nosocomial infections of implanted medical devices pose a significant health risk to patients, with Staphylococcus epidermidis often implicated in the case of blood‐contacting biomaterials. S. epidermidis virulence relies mainly on its ability to form a biofilm, the main component of which is polysaccharide intercellular adhesin (PIA). We utilized the synthetic β6‐20 peptide, known to specifically bind S. epidermidis, in order to deliver a cationic polylysine peptide (G3K6) to the bacterial surface and disrupt the charge–charge interactions needed for PIA retention and biofilm stability. The effects of the β6‐20‐G3K6 peptide on biofilm formation were assessed using optical density, fluorescently labeled wheat germ agglutinin, nucleic acid stain (SYTO 9), and a metabolic assay (XTT, 2,3‐bis(2‐methoxy‐4‐nitro‐5‐sulfophenyl)‐2H‐tetrazolium‐5‐carboxanilide inner salt). Biofilms formed in the presence of β6‐20‐G3K6 peptide (100 μM) resulted in a 37.9% reduction in PIA content and a 17.5% reduction of adherent bacteria relative to biofilms grown in the absence of peptide. These studies demonstrate the targeting ability of the β6‐20 peptide towards biomaterial‐adherent S.
epidermidis, and highlight the potential for disrupting the early stages of biofilm formation. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
Osteoblast activity on carbonated hydroxyapatite
Authors: Rupani Asha , Hidalgo‐Bastida Lilia Araida , Rutten Frank , Dent Andrew , Turner Irene , Cartmell Sarah
Published: February 2012

Hydroxyapatite (HA), has been used commonly as a bone substitute and as a scaffold in bone tissue engineering. However it has certain drawbacks such as limited biodegradability and osteointegration properties. Other forms of HA, for example, carbonated hydroxyapatite (CHA) could prove to have enhanced bioactivity as they more closely mimic the chemical composition of the apatite found in human bone. The aim of this study was to test the efficacy of CHA in comparison to HA used as a control. The CHA (4.9 wt %) and the HA discs were seeded with MC3T3‐E1 osteoblastic cells. Results revealed a trend of increased cell attachment on the HA discs at day 0, however, the cell proliferation on the CHA discs at 7 and 28 days showed no significant difference in comparison to the HA control. SEM of the CHA discs showed surface irregularities at 7 days indicating dissolution. Also at 7 days, SEM demonstrated cell attachment and extracellular matrix production on both the CHA and HA samples. There was no significant difference in the total amount of collagen produced in the CHA samples relative to the HA control samples at 28 days as evaluated by the hydroxyproline assay. Real time PCR revealed mRNA increase by 2.08, 7.62, and 9.86 fold for collagen I a1, collagen III a1, and osteocalcin respectively on the CHA as compared to the HA discs. This study demonstrates the use of CHA as a biocompatible material that has potentially increased biodegradation properties and osteogenic capability in comparison to HA. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
A [Fe(CB6)] platform for binding of small molecules: Insights from DFT calculations
Authors: Baskaran Sambath , Tamizmani Masilamani , Mahalakshmi Thanigachalam , Sivasankar Chinnappan
Published: February 2012

The viability of making [Fe(CB6)L] (L = H2, N2, O2, nitric oxide [NO−, NO, and NO+], CO2, and hydrocarbons [CH4, C2H6, C2H4, and C6H6]) has been investigated by density functional theory (DFT) calculations. The complexes 2–18 are thermodynamically stable and may be synthesized. The small molecules are activated to some extent after complexation. Molecular orbital and ΔG calculation revealed that the molecular hydrogen and hydrocarbons can be chemically adsorbed and desorbed on [Fe(CB6)] without any significant chemical modification and therefore [Fe(CB6)] may serve as a storage material. The N2, O2, and nitric oxide (NO−, NO, and NO+) can be activated using [Fe(CB6)]. Proton, carbon, boron, and nitrogen NMR chemical shift calculation predicts drastic chemical shift difference before and after the complexation of [Fe(CB6)] with small molecules. This new findings suggest that the CB62− ligand‐based complex may provide several applications in the future. © 2012 Wiley Periodicals, Inc.
Internal anatomy and ultrastructure of the male reproductive system of the Norway lobster Nephrops norvegicus (Decapoda: Astacidea)
Authors: Rotllant Guiomar , Chiva Manel , Durfort Mercè , Ribes Enric
Published: February 2012

The Norway lobster (Nephrops norvegicus) is economically important in Europe. However, apart from the female reproductive system, very little is known about its internal anatomy. This article focuses on studying the internal anatomy and ultrastructure of the male reproductive system. This system follows the general pattern found among decapod crustaceans, with several peculiarities. Testes are composed of lobular sperm ducts in which the spermatozoa are fully constituted. The spermatozoa present three lateral arms and a long acrosome, which gives a false appearance of flagellated spermatozoa. The two testes form a double H under the heart, and the vas deferens (VD) arise from each side at the posterior edge of the double H. The main characteristic of the VD is the presence of a sphincter in the enlarged area of the distal end of the middle VD. The MVD here shows an increase in musculature of the wall as compared to the VD, which regulates the passage of the sperm cord to the distal VD (DVD) and thence to the thelycum of the female. The wall of the spermatophore is formed in the distal part of the proximal VD, which surrounds the unique sperm cord present in the VD. Isolated spermatophores are not observed in the VD. The sperm cord is pinched off during copulation by the musculature of the DVD. Then, a portion of the sperm cord is transferred from each VD to form the isolated spermatophores. The wall of the spematophores and the spermatozoa that are observed inside the thelycum have the same morphology as those observed in the VD. J. Morphol., 2012. © 2012 Wiley Periodicals, Inc.
Understanding the basic mechanisms underlying seizures in mesial temporal lobe epilepsy and possible therapeutic targets: A review
Authors: O'Dell Casey M. , Das Arabinda , Wallace Gerald , Ray Swapan K. , Banik Naren L.
Published: February 2012

Despite years of research, epilepsy remains a poorly understood disorder. In the past several years, work has been conducted on a variety of projects with the goal of better understanding the pathogenesis and progression of mesial temporal lobe epilepsy (MTLE), in particular, and how to exploit those properties to generate innovative therapies for treatment of refractory epilepsies. This review seeks to give an overview of common morphological and biochemical changes associated with epilepsy and proposed treatments to address those changes. Furthering the understanding of ictogenesis and epileptogenesis remains an important goal for scientists seeking to find more effective treatments for MTLE. © 2012 Wiley Periodicals, Inc.
Antioxidant and antimicrobial potentials of Serbian red wines produced from international Vitis vinifera grape varieties
Authors: Radovanović Aleksandra N , Jovančićević Branimir S , Radovanović Blaga C , Mihajilov‐Krstev Tatjana , Zvezdanović Jelena B
Published: February 2012

BACKGROUND: Antioxidant and antimicrobial potentials of Serbian red wines produced from different international Vitis vinifera grape varieties and their correlation with contents of phenolic compounds were studied by spectrophotometric and chromatographic methods. The antioxidant activity of red wines was estimated through their ability to scavenge 2,2′‐diphenyl‐1‐picrylhydrazyl free radical (DPPH•). The red wines, gallic acid, (+)‐catechin and quercetin were screened in vitro for antimicrobial activity against Gram‐positive and Gram‐negative strains using microdilution and disc diffusion techniques.

RESULTS: Excellent correlations between the contents of quercetin‐3‐glucoside (R2 = 0.9463) and quercetin (R2 = 0.9337) and DPPH•‐scavenging ability of the red wines were found. Serbian red wines exhibited significant activity against Staphylococcus aureus, Listeria inocua, Micrococcus flavus, Sarcina lutea, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis and Shigella sonnei strains, which was in correlation with their phenolic composition and antioxidant activity. The compounds gallic acid, quercetin and (+)‐catechin showed high activity against B. subtilis, S. aureus, S. lutea and M. flavus Gram‐positive and S. enteritidis and P. aeruginosa Gram‐negative strains.

CONCLUSION: The results show that quercetin‐3‐glucoside and quercetin concentrations can be used as markers for the determination of antioxidant and antimicrobial potentials of red wines. Copyright © 2012 Society of Chemical Industry
Combined effect of electrical stimulation, aging time and marination on quality of chicken breast fillet processed under commercial conditions
Authors: Perlo Flavia , Bonato Patricia , Fabre Romina , Teira Gustavo , Tisocco Osvaldo
Published: February 2012

BACKGROUND: Electrical stimulation (ES) in poultry processing is reported in the literature with varying degrees of effectiveness. Furthermore, the combined effects of ES and polyphosphate marination are not completely known. The objective of this study was to evaluate the combined effect of ES, aging time prior to deboning and phosphate marination on meat quality of broiler breast fillets.

RESULTS: The implementation of ES accelerated pH decline in fillets at any aging time studied regardless of marination treatment, but no differences (P > 0.05) were found in pH of fillets deboned without aging. Warner–Bratzler (WB) shear values of ES fillets significantly decreased (P < 0.05) at 2 h of aging whereas WB of non‐ES fillets decreased at 6 h of aging in breast meat, with or without marination. In non‐marinated fillets the ES treatment reduced (P < 0.05) cooking loss in meat aged 0, 2 and 4 h. In marinated fillets the ES treatment decreased cooking loss at 2, 4, 6 and 8 h of aging.

CONCLUSION: ES in carcasses aged 2 or 4 h improves tenderness and reduces cooking loss. Marination improves tenderness in both stimulated and non‐stimulated fillets, at all aging times. Copyright © 2012 Society of Chemical Industry
Microwave‐assisted extraction combined with dispersive liquid–liquid microextraction as a new approach to determination of chlorophenols in soil and sediments
Authors: Naeeni Mohammad Hosein , Yamini Yadollah , Rezaee Mohammad , Seidi Shahram
Published: February 2012

A new method was applied for extraction of five chlorophenols from soil and marine sediment samples. Microwave‐assisted extraction coupled with dispersive liquid–liquid microextraction followed by semi‐automated in‐syringe back‐extraction technique was used as an extraction technique. Microwave‐assisted extraction was performed by using 2.0 mL of alkaline water at pH 10.0. After extraction, the pH of extraction solution was adjusted at 6.0 and dispersive liquid–liquid microextraction procedure was done using 1.0 mL of acetone as a disperser solvent and 37.0 μL of chlorobenzene as extraction solvent. About 20.0 ± 0.5 μL sedimented phase was collected after centrifugation step. Then, chlorophenols were back extracted into 20 μL of alkaline water at pH 12.0 within the microsyringe. Finally, 20.0 μL of aqueous solution was injected into high performance liquid chromatography with ultra violet detection for analysis. The obtained recovery and preconcentration factors for the analytes were in the range of 68.0–82.0% and 25–30, respectively, with relative standard deviations ≤7.6%. The limits of the detection were found in the range of 0.0005–0.002 mg/kg. The method provides a simple and fast procedure for the extraction and determination of chlorophenols in soil and marine sediment samples.
Isolation of egg‐yolk phospholipids and enzymatic modification of their acyl chains
Authors: Chojnacka Anna , Gladkowski Witold , Kielbowicz Grzegorz , Wawrzenczyk Czeslaw
Published: February 2012

Phospholipids (PLs) have many biological and technological functions. Among the main sources of PLs egg yolk is the most attractive because of the high content of phosphatidylcholine (PC). The nutritional value of PLs can be increased by different methods, including enzymatic enrichment with polyunsaturated fatty acids (PUFA). Depending on the enzymes and reaction systems used, a‐linolenic acid (ALA) was introduced into the sn‐1 or sn‐2 position. Useful methods of PL isolation and positional analysis were elaborated.
Elasto‐aerodynamic lubrication analysis of a self‐acting air foil journal bearing
Authors: Bensouilah Hamza , Lahmar Mustapha , Bou‐Saïd Benyebka
Published: February 2012

Nowadays, air foil bearings find widespread use in very high speed, lightly loaded oil‐free rotating turbomachineries such as compressors and microgas turbines because they have theoretically no speed limitations and they are environmentally benign. In the design of such bearings, it is of cardinal importance to enhance their steady‐state and dynamic performance characteristics for the safety operation, especially against the external dynamic excitations. Most of elasto‐aerodynamic approaches under dynamic conditions proposed in the technical literature include only the static pressure induced deformation of foils. This paper presents a theoretical investigation on the effects of both static and dynamic deformations of the foils on the dynamic performance characteristics and stability of a self‐acting air foil journal bearing operating under small harmonic vibrations. For the dynamic deformations of foils to be taken into account, the perturbation method is used for determining the gas‐film stiffness and damping coefficients for given values of excitation frequency, compressibility number and compliance factor of the bump foil. The rotor‐dynamic coefficients serve as input data for the linear stability analysis of rotor‐bearing system. The nonlinear stationary Reynolds' equation is solved by means of the Galerkin's finite element formulation, whereas the finite differences method are used to solve the first‐order complex dynamic equations resulting from the perturbation of the transient compressible Reynolds' equation. As a first approximation, the corrugated subfoil is modelled as a simple elastic foundation, i.e. the stiffness of a bump is uniformly distributed throughout the bearing surface. It was found that the dynamic properties and stability of the compliant finite length journal bearing are significantly affected by the compliance of foils especially when the dynamic deformation of foils is considered in addition to the static one by applying the principle of superposition. Copyright © 2012 John Wiley & Sons, Ltd.
Treatment with sildenafil and treprostinil allows successful liver transplantation of patients with moderate to severe portopulmonary hypertension
Authors: Hollatz Trina J. , Musat Alexandru , Westphal Susanne , Decker Catherine , D'Alessandro Anthony M. , Keevil Jon , Zhanhai Li , Runo James R.
Published: February 2012

Portopulmonary hypertension (PoPH) refers to pulmonary arterial hypertension associated with portal hypertension with or without evidence of an underlying liver disease. Despite the potential for curing PoPH with liver transplantation, the presence of moderate or severe PoPH is associated with increased morbidity and mortality and is, therefore, a contraindication to transplantation. Previous studies have predominantly used intravenous epoprostenol for treatment in order to qualify patients for liver transplantation. In this retrospective case series, we describe the clinical course of 11 patients whom we successfully treated (predominantly with oral sildenafil and subcutaneous treprostinil) in order to qualify them for liver transplantation. The mean pulmonary artery pressure significantly improved from 44 to 32.9 mm Hg, and the pulmonary vascular resistance decreased from 431 to 173 dyn second cm−5. There were significant improvements in the cardiac output and the transpulmonary gradient with these therapies as well. All 11 patients subsequently received liver transplants with a 0% mortality rate to date; the duration of follow-up ranged from 7 to 60 months. After transplantation, 7 of the 11 patients (64%) were off all pulmonary vasodilators, and only 2 patients required transiently increased doses of prostacyclins. In conclusion, an aggressive approach to the treatment of PoPH with sildenafil and/or treprostinil and subsequent liver transplantation may be curative for PoPH in some patients.
Gelation on Heating of Supercooled Gelatin Solutions
Authors: Guigo Nathanaël , Sbirrazzuoli Nicolas , Vyazovkin Sergey
Published: February 2012

Diluted (1.0–1.5 wt%) aqueous gelatin solutions have been cooled to –10 °C at a cooling rate 20 °C min−1 without freezing and detectable gelation. When heated at a constant heating rate (0.5 –2 °C min−1), the obtained supercooled solutions demonstrate an atypical process of gelation that has been characterized by regular and stochastically modulated differential scanning calorimetry (DSC) as well as by isoconversional kinetic analysis. The process is detectable as an exothermic peak in the total heat flow of regular DSC and in the nonreversing heat flow of stochastically modulated DSC. Isoconversional kinetic analysis applied to DSC data reveals that the effective activation energy of the process increases from approximately 75 to 200 kJ mol−1 as a supercooled solution transforms to gel on continuous h eating.
Automatic Perception of Chemical Similarities Between Metabolic Pathways
Authors: Latino Diogo A. R. S. , Aires‐de‐Sousa João
Published: February 2012

Metabolic pathways are at the crossroad between the chemical world of small molecules and the biological world of enzymes, genes and regulation. Methods for their processing are therefore required for a great variety of applications. The work presented here reports a new method to encode metabolic pathways and reactomes of organisms based on the MOLMAP approach. Pathways are represented from features of the metabolites involved in their reactions enabling to automatically perceive chemical similarities, and making no use of EC numbers. MOLMAP descriptors are based on atomic topological and physicochemical features of the bonds involved in reactions. The results show that self‐organizing maps (SOM) can be trained with MOLMAPs of pathways to automatically recognize similarities between pathways of the same type of metabolism. The study also illustrates the possibility of applying the MOLMAP methodology at progressively higher levels of complexity, bridging chemical and biological information, and going all the way from atomic properties to the classification of organisms.
TFMCC versus ASMP: lessons learned from performance evaluation
Authors: Kioumourtzis Georgios , Bouras Christos , Gkamas Apostolos
Published: February 2012

In this article we present a simulation‐based comparison of one of the best‐known multicast congestion control schemes—TCP‐friendly Multicast Congestion Control (TFMCC)—against our proposed Adaptive Smooth Multicast Protocol (ASMP). ASMP consists of a single‐rate multicast congestion control mechanism which takes advantage of the RTCP Sender (SR) and Receiver Reports (RR) in order to adjust the sender's transmission rate in respect of the network conditions. The innovation in ASMP lays in the ‘smooth’ transmission rate, which is TCP‐friendly and prevents oscillations. We use an integrated simulation environment named Multi‐Evalvid‐RA for the evaluation of the two congestion control schemes. Multi‐Evalvid‐RA provides all the necessary tools to perform simulation studies and assess video quality by using both network‐centric metrics along with video quality measurements. Performance evaluation results show that ASMP is a very efficient solution for rate‐adaptive multimedia applications and a serious competitor to well‐known TFMCC. Copyright © 2012 John Wiley & Sons, Ltd.
Electronic healthcare databases for active drug safety surveillance: is there enough leverage?
Authors: Coloma Preciosa M. , Trifirò Gianluca , Schuemie Martijn J. , Gini Rosa , Herings Ron , Hippisley‐Cox Julia , Mazzaglia Giampiero , Picelli Gino , Corrao Giovanni , Pedersen Lars , van der Lei Johan , Sturkenboom Miriam ,   on behalf of the EU‐ADR consortium
Published: February 2012

Purpose

To provide estimates of the number and types of drugs that can be monitored for safety surveillance using electronic healthcare databases.

Methods

Using data from eight European databases (administrative claims, medical records) and in the context of a cohort study, we determined the amount of drug exposure required for signal detection across varying magnitudes of relative risk (RR). We provide estimates of the number and types of drugs that can be monitored as a function of actual use, minimal detectable RR, and empirically derived incidence rates for the following adverse events: (i) acute myocardial infarction; (ii) acute renal failure; (iii) anaphylactic shock; (iv) bullous eruptions; (v) rhabdomyolysis; and (vi) upper gastrointestinal bleeding. We performed data simulation to see how expansion of database size would influence the capabilities of such system.

Results

Data from 19 647 452 individuals (59 594 132 person‐years follow‐up) who used 2289 drugs in the EU‐ADR network show that for a frequent event such as acute myocardial infarction, there are 531 drugs (23% of total) for which an association with RR = 2, if present, can be investigated. For a rare event such as rhabdomyolysis, there are 19 drugs (1%) for which an association of same magnitude can be investigated.

Conclusion

Active surveillance using healthcare data‐based networks for signal detection is feasible, although the leverage to do so may be low for infrequently used drugs and for rare outcomes. Extending database network size to include data from heterogeneous populations and increasing follow‐up time are warranted to maximize leverage of these surveillance systems. Copyright © 2012 John Wiley & Sons, Ltd.
Simulations of substrate transport in the multidrug transporter EmrD
Authors: Baker Joseph , Wright Stephen H. , Tama Florence
Published: February 2012

EmrD is a multidrug resistance (MDR) transporter from Escherichia coli, which is involved in the efflux of amphipathic compounds from the cytoplasm, and the first MDR member of the major facilitator superfamily to be crystallized. Molecular dynamics simulation of EmrD in a phospholipid bilayer was used to characterize the conformational dynamics of the protein. Motions that support a previously proposed lateral diffusion pathway for substrate from the cytoplasmic membrane leaflet into the EmrD central cavity were observed. In addition, the translocation pathway of meta‐chloro carbonylcyanide phenylhydrazone (CCCP) was probed using both standard and steered molecular dynamics simulation. In particular, interactions of a few specific residues with CCCP have been identified. Finally, a large motion of two residues, Val 45 and Leu 233, was observed with the passage of CCCP into the periplasmic space, placing a lower bound on the extent of opening required at this end of the protein for substrate transport. Overall, our simulations probe details of the transport pathway, motions of EmrD at an atomic level of detail, and offer new insights into the functioning of MDR transporters. Proteins 2012; © 2012 Wiley Periodicals, Inc.
Development of a high‐throughput real‐time PCR assay for the detection of the R81T mutation in the nicotinic acetylcholine receptor of neonicotinoid‐resistant Myzus persicae
Authors: Puinean Alin M , Elias Jan , Slater Russell , Warren Anne , Field Linda M , Williamson Martin S , Bass Chris
Published: February 2012

BACKGROUND: Myzus persicae is a globally important aphid pest that is mainly controlled through the application of chemical insecticides. Recently, a clone of M. persicae exhibiting control‐compromising levels of resistance to neonicotinoid insecticides was described. The resistance of this clone was associated with reduced affinity of imidacloprid for the target site (the nicotinic acetylcholine receptor) as a result of mutation of a key amino acid residue (R81T) in the loop D region of a nAChR β1 subunit. The potent levels of resistance conferred by this mechanism are cause for considerable concern, and the frequency and distribution of the mutation in worldwide populations of M. persicae require careful monitoring. In this study, a high‐throughput assay has been developed that allows detection of the mutation in individual aphids.

RESULTS: A real‐time TaqMan assay to detect the R81T substitution was developed that proved to be sensitive and specific in tests of analytical sensitivity and in a blind genotyping trial of DNA extracted from individual aphids comprising the three possible genotypes. The assay was then used to examine the frequency of the R81T mutation in aphids collected and stored in ethanol from peach orchards in southern France. The R81T frequency varied from 33 to 100% in seven populations from the department of Gard, France.

CONCLUSIONS: This study describes a rapid and sensitive assay that very effectively detects the R81T mutation in individual aphids. The results also have practical significance for the control of M. persicae in southern France and provide contemporary data to inform current resistance management strategies. Copyright © 2012 Society of Chemical Industry
Bioactivity‐guided Fractionation of Phyllanthus orbicularis and Identification of the Principal Anti HSV‐2 Compounds
Authors: Álvarez Ángel L. , Dalton Kevin P. , Nicieza Inés , Diñeiro Yolanda , Picinelli Anna , Melón Santiago , Roque Annele , Suárez Belén , Parra Francisco
Published: February 2012

The antiherpes virus properties of Phyllanthus orbicularis Kunth, a Cuban‐endemic medicinal plant, have been reported previously but data on its phytochemical profile and identification of antiviral metabolites as well as their mechanisms of action are still lacking. In this work, a bioactivity‐guided phytochemical analysis was performed in order to isolate anti HSV‐2 compounds. P. orbicularis contained mainly phenolic acids derivatives and flavonoids. The antiviral effects were attributed to (−)‐epicatechin‐3‐O‐gallate (EC50 = 11.7 µg/mL), procyanidins B1 and B2 (EC50 = 32.8 µg/mL and 24.2 µg/mL, respectively) as well as oligomeric and polymeric procyanidins and their gallate derivatives. The antiviral mechanisms of the active P. orbicularis extracts and fractions were also investigated and the inhibition of several HSV‐2 early replication events and DNA synthesis were observed. This is the first study of extensive fractionation and phytochemical characterization of phenolic compounds from this species. Copyright © 2012 John Wiley & Sons, Ltd.
Nonparametric Estimator for the Time of a Step Change in the Trend of Random Walk Models with Drift
Authors: Tercero‐Gómez Víctor G , del Carmen Temblador‐Pérez María , Beruvides Mario , Hernández‐Luna Alberto
Published: February 2012

Living systems tend to have non‐normal behaviors, are autocorrelated, exhibit patterns of growth or decrement, and achieve states of dynamic equilibrium, making them hard to manage. One way to manage and improve these complex systems is by identifying assignable causes of variation whenever they occur, and control charts are one of the most known tool for those situations. However, in the presence of sustained changes, control charts are not capable of telling the initial moment of a change. This paper proposes a nonparametric estimator capable of dealing with non‐normal observations heterocedastic over time. The median test is used to estimate the time of a step change in Shewhart Control Charts using a relatively successful approach based on a binary segmentation approach. Furthermore, an application is developed to deal with changes on the trend of processes fitting a random walk with drift. Performance is evaluated with extensive Monte Carlo simulations, and results are compared with the maximum likelihood estimator for normal series of independent observations. Results showed acceptable performance when normality is not met and robustness under heterocedasticity. Copyright © 2012 John Wiley & Sons, Ltd.
A Note on “Capability Assessment for Processes with Multiple Characteristics: A Generalization of the Popular Index Cpk”
Authors: Pearn W. L. , Wu C. H. , Tsai M. C.
Published: February 2012

The generalized yield index establishes the relationship between the manufacturing specifications and the actual process performance, which provides a lower bound on process yield for two‐sided processes with multiple characteristics. The results attended are very practical for industrial application. In this article, we extended the results in cases with one‐sided specification and multiple characteristics. The generalized index was considered, and the asymptotic distribution of the natural estimator was developed. Then, we derived the lower confidence bounds as well as the critical values of index . We not only provided some tables but also presented an application example. Copyright © 2012 John Wiley & Sons, Ltd.
Transient increases in dendritic spine density contribute to dentate gyrus long‐term potentiation
Authors: Wosiski‐Kuhn Marlena , Stranahan Alexis M.
Published: February 2012

Dendritic spines are the primary sites for excitatory neurotransmission in the adult brain and exhibit changes in their number and morphology with experience. The relationship between spine formation and synaptic activity has been best characterized along the apical dendrites of pyramidal neurons in the hippocampal CA1 subfield. However, less is known about the structural mechanisms at the spine that mediate plasticity in other hippocampal subfields. The dentate gyrus is the predominant point of entry for synaptic input to the hippocampus, and dentate granule cells differ from CA1 pyramidal neurons in terms of their morphology and biophysical properties. In order to understand the structural mechanisms for plasticity in the dentate gyrus, we measured dendritic spine density in hippocampal slice preparations at different intervals following synaptic stimulation. We observed that transient increases in dendritic spine density are detectable 30 min after induction of long‐term potentiation (LTP). By 60 min poststimulation, dendritic spine density has returned to basal levels. Both early LTP and enhancements in dendritic spine density could beblocked by destabilizing actin filaments, but not by inhibitors of transcription or protein synthesis. These results indicate that spine formation is a transient event that is required for dentate gyrus LTP. Synapse, 2012. © 2011 Wiley Periodicals, Inc.
Effects of amphetamine on subcellular distribution of dopamine and DOPAC
Authors: Wallace Lane J.
Published: February 2012

Amphetamine effects on distribution of dopamine, 3,4‐dihydroxyphenylacetic acid (DOPAC), and amphetamine in vesicular, cytosolic, and extracellular compartments associated with a striatal varicosity were estimated through use of a computer simulation model. In addition, contribution to overall effects of amphetamine by each of five actions—transport by dopamine transporter (DAT), transport by vesicular monoamine transporter, stimulation of reverse transport, inhibition of monoamine oxidase (MAO), and slowing of dopamine cell firing rate—were evaluated. Amphetamine enters a varicosity almost entirely by DAT and accumulates to very high levels within the varicosity. Both reverse transport by DAT and passive diffusion contribute to continual amphetamine egress across the plasma membrane. Amphetamine enters storage vesicles by both transport and diffusion. The transport portion competes with dopamine storage, resulting in redistribution of approximately half of dopamine from vesicles to cytosol. The high concentration of amphetamine in the cytosol inhibits MAO, protecting cytosolic dopamine. A very small fraction of cytosolic dopamine is moved to extracellular compartment via reverse transport by DAT. The amount of dopamine moved by reverse transport is limited because of competition by very high cytosolic levels of amphetamine. In the presence of amphetamine, rate of dopamine transfer to extracellular compartment is less than control; however, high levels of extracellular dopamine are maintained because amphetamine occupies the DAT, thus limiting dopamine reuptake. Simulation output from a model using exchange‐diffusion mechanism of reverse transport does not match all published data that were simulated, suggesting that inward transport of a substrate is not required to initiate reverse transport. Synapse, 2012. © 2012 Wiley Periodicals, Inc.
The forward-backward top asymmetry in a singlet extension of the MSSM
Authors: de la Puente Alejandro
Published: February 2012

Abstract

The CDF and DØ collaborations have recently reported a large forward- backward asymmetry in the
$ t\overline t $
system which deviates from the next to-leading order QCD standard model prediction. We study the asymmetry in the
$ t\overline t $
system within the framework of singlet extensions of the Minimal Supersymmetric Standard Model. For this purpose, we introduce non-renormalizable couplings between first and third generation of quarks to scalars. We analyze two limiting cases of the model, characterized by the size of the supersymmetric mass for the singlet superfield. We study both the small and large limits of this mass parameter. We find that in the region of small singlet supersymmetric mass we can obtain a large asymmetry while being consistent with limits on the
$ t\overline t $
production cross section. These results are also consistent with constraints arising from flavor physics, quark masses and top quark decays.
Design and Fabrication of Tubular Scaffolds via Direct Writing in a Melt Electrospinning Mode
Authors: Brown Toby D. , Slotosch Anna , Thibaudeau Laure , Taubenberger Anna , Loessner Daniela , Vaquette Cedryck , Dalton Paul D. , Hutmacher Dietmar W.
Published: February 2012

Flexible tubular structures fabricated from solution electrospun fibers are finding increasing use in tissue engineering applications. However it is difficult to control the deposition of fibers due to the chaotic nature of the solution electrospinning jet. By using non-conductive polymer melts instead of polymer solutions the path and collection of the fiber becomes predictable. In this work we demonstrate the melt electrospinning of polycaprolactone in a direct writing mode onto a rotating cylinder. This allows the design and fabrication of tubes using 20 μm diameter fibers with controllable micropatterns and mechanical properties. A key design parameter is the fiber winding angle, where it allows control over scaffold pore morphology (e.g. size, shape, number and porosity). Furthermore, the establishment of a finite element model as a predictive design tool is validated against mechanical testing results of melt electrospun tubes to show that a lesser winding angle provides improved mechanical response to uniaxial tension and compression. In addition, we show that melt electrospun tubes support the growth of three different cell types in vitro and are therefore promising scaffolds for tissue engineering applications.
Soft‐tissue profile changes after orthognathic surgery of mandibular prognathism
Authors: Chen Chun‐Ming , Lai Steven , Lee Huey‐Er , Chen Ker‐Kong , Hsu Kun‐Jung
Published: February 2012

During surgical correction of facial deformities, accurate prediction of the resulting facial profile is important for the patient and the surgeon. The purpose of the present study was to investigate profile changes after surgical treatment of mandibular prognathism. Thirty patients (20 females and 10 males; ages 17–28 years) with mandibular prognathism underwent vertical ramus osteotomy. Preoperative and postoperative cephalograms were analyzed; landmarks were identified and compared. The mean horizontal setback of the pogonion (Pog) was 11.7 mm. The setback ratios of labrale inferius (Li)/incision inferius (Ii), labiomental sulcus (Si)/point B, and soft tissue pogonion (PogS)/pogonion (Pog) were 0.98, 0.99, and 0.95, respectively. There were no sex‐related changes in soft tissue. These findings indicate that changes in soft tissue closely correlate with the amount of mandibular setback in the horizontal direction. Such information might facilitate more accurate prediction of the outcome of orthognathic surgery.
Dissipation, enstrophy and pressure statistics in turbulence simulations at high Reynolds numbers
Authors: Yeung P. K. , Donzis D. A. , Sreenivasan K. R.
Published: February 2012

We use data from well-resolved direct numerical simulations at Taylor-scale Reynolds numbers from 140 to 1000 to study the statistics of energy dissipation rate and enstrophy density (i.e. the square of local vorticity). Despite substantial variability in each of these variables, their extreme events not only scale in a similar manner but also progressively tend to occur spatially together as the Reynolds number increases. Though they possess non-Gaussian tails of enormous amplitudes, ratios of some characteristic properties can be closely linked to those of isotropic Gaussian random fields. We present results also on statistics of the pressure Laplacian and conditional mean pressure given both dissipation and enstrophy. At low Reynolds number intense negative pressure fluctuations are preferentially associated with rotation-dominated regions but at high Reynolds number both high dissipation and high enstrophy have similar effects.
Lichenicolous fungi growing onThamnolia, mainly from the Holarctic, with a worldwide key to the known species
Authors: ZHURBENKO Mikhail P.
Published: February 2012

Twenty species of lichenicolous fungi are reported onThamnoliaspecies and discussed.Epithamnolia karatyginiigen. et sp. nov.,Capronia thamnoliaesp. nov.,Cercidospora epithamnoliasp. nov.,C. thamnogalloidessp. nov.,C. thamnoliaesp. nov., andSphaerellothecium thamnoliaesp. nov. (var.thamnoliae, var.taimyricum) are described fromThamnolia.Dacampia thamnoliicolaandPhoma thamnoliaeare introducedad interim.Cercidospora lecidomaeis reduced to synonymy withC. punctillata.Polycoccum vermiculariumis new to Asia,Odontotrema santessoniiandO. thamnoliaeare new to North America,Cladosporium licheniphilumis new to the Arctic,Thamnogalla crombieiis new to Greenland and Svalbard,Stigmidium frigidumis new to Mongolia and confirmed in the USA,Lichenopeltella thamnoliaeis new to Bolivia.Cladosporium licheniphilumandPhaeospora arcticaare newly documented onThamnoliaandLichenopeltella thamnoliaeonThamnolia papelillovar.subsolida.Thamnolia vermicularis, supporting 23 species of lichenicolous fungi, is shown to be the 15th most hospitable lichen species in the world. A worldwide key to 23 species of fungi known to occur onThamnoliais provided.