bluuebunny/crossref_metadata_2025_split huggingface dataset:
A defensin‐like antimicrobial peptide from the venoms of spider, Ornithoctonus hainana
Authors: Zhao Hongwen , Kong Yi , Wang Hanjin , Yan Tianhua , Feng Feifei , Bian Jianmin , Yang Yan , Yu Haining 
Published: April 2011

AbstractThe defensin‐like antimicrobial peptides have been characterized from various other arthropods including insects, scorpions, and ticks. But no natural spider defensin‐like antimicrobial peptides have ever been isolated from spiders, except couple of cDNA and DNA sequences of five spider species revealed by previous genomic study. In this work, a defensin‐like antimicrobial peptide named Oh‐defensin was purified and characterized from the venoms of the spider, Ornithoctonus hainana. Oh‐defensin is composed of 52 amino acid (aa) residues including six Cys residues that possibly form three disulfide bridges. Its aa sequence is MLCKLSMFGAVLGV PACAIDCLPMGKTGGSCEGGVCGCRKLTFKILWDKKFG. By BLAST search, Oh‐defensin showed significant sequence similarity to other arthropod antimicrobial peptides of the defensin family. Oh‐defensin exerted potent antimicrobial activities against tested microorganisms including Gram‐positive bacteria, Gram‐negative bacteria, and fungi. The cDNA encoding Oh‐defensin precursor was also cloned from the cDNA library of O. hainana. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
Molecular modeling study of the opioid receptor interactions with series of cyclic deltorphin analogues
Authors: Ślusarz Magdalena J. 
Published: April 2011

AbstractIn this study, ten tetra‐ and heptapeptide analogues of deltorphin containing the urea bridges between residues 2 and 4 have been docked into the δ‐ and µ‐opioid receptors to explain their different biological activities. The important factors explaining particular ligand activity such as free energy of binding, conformation of the ligand, its location inside the binding pocket as well as the number and strength of the receptor–ligand interactions have been discussed. Several different binding modes for investigated ligands have been proposed. It appears that the binding site is not identical even for very similar ligands. Results of this study help to explain the differences in biological activity of the deltorphin analogues, their interaction with the opioid receptors at the molecular level and support designing a new generation of potent opioid drugs with improved selectivity. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
When is R2 appropriate for comparing customer and supplier measurement systems?
Authors: Nachtsheim Christopher J. , Becker Kevin E. 
Published: April 2011

AbstractLinear regression analysis is often used to compare paired supplier and customer measurements of a given quantitative product characteristic in a shipment of products. Specifically, the coefficient of determination, R2, is then used to determine if the supplier's and the buyer's measurement systems are in conformity, with sufficiently high values implying agreement. In this article, we show that R2 istextitnever an appropriate statistic for making this determination. Examples are provided and an appropriate methodology for comparing two measurement systems is delineated. Copyright © 2011 John Wiley & Sons, Ltd.
Active role of hydrogen bond and ambient water in Meyer–Schuster rearrangements in high‐temperature water
Authors: Wang Zhizhong , Chang Yongjuan , Gong Xinxin , Dai Liyi 
Published: April 2011

AbstractMeyer–Schuster rearrangements of 2‐phenyl‐3‐butyn‐2‐ol with H3O+ and (H2O)6 model in high‐temperature water (HTW) have been investigated by the use of density functional theory calculations. In the substrate 2‐phenyl‐3‐butyn‐2‐ol catalyzed by H3O+ and (H2O)6, the Meyer–Schuster rearrangements were predicted by the frontier molecular orbital theory. The results show that the rearrangement does not involve the carbonium ion intermediates, but the first transition state is carboniumion like. Dehydration and hydration may occur via the intermolecular proton relay along the hydrogen‐bond chains and the second step of reaction path is a total acid–base catalytic process. Based on the results, a model considered both HTW ambient and water molecules are proposed to represent mechanisms of other reactions in HTW. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Optimal transseptal puncture location for robot‐assisted left atrial catheter ablation
Authors: Jayender J. , Patel R. V. , Michaud G. F. , Hata N. 
Published: April 2011

AbstractBackgroundThe preferred method of treatment for atrial fibrillation (AF) is by catheter ablation, in which a catheter is guided into the left atrium through a transseptal puncture. However, the transseptal puncture constrains the catheter, thereby limiting its manoeuvrability and increasing the difficulty in reaching various locations in the left atrium. In this paper, we address the problem of choosing the optimal transseptal puncture location for performing cardiac ablation to obtain maximum manoeuvrability of the catheter.MethodsWe have employed an optimization algorithm to maximize the global isotropy index (GII) to evaluate the optimal transseptal puncture location. As part of this algorithm, a novel kinematic model for the catheter has been developed, based on a continuum robot model. Pre‐operative MR/CT images of the heart are segmented using the open source image‐guided therapy software, 3D Slicer, to obtain models of the left atrium and septal wall. These models are input to the optimization algorithm to evaluate the optimal transseptal puncture location.ResultsThe continuum robot model accurately describes the kinematics of the catheter. Simulation and experimental results for the optimal transseptal puncture location are presented in this paper. The optimization algorithm generates discrete points on the septal wall for which the dexterity of the catheter in the left atrium is maximum, corresponding to a GII of 0.4362.ConclusionWe have developed an optimization algorithm based on the GII to evaluate the optimal position of the transseptal puncture for left atrial cardiac ablation. Copyright © 2011 John Wiley & Sons, Ltd.
Viruses and the fuel sensor: the emerging link between AMPK and virus replication
Authors: Mankouri Jamel , Harris Mark 
Published: April 2011

SUMMARYAdenosine 5′ monophosphate‐activated protein kinase (AMPK) is conserved in all eukaryotic cells and functions as the key regulator of cellular metabolism by responding to the energy status of the cell. It is activated by an increase in the AMP : ATP ratio and then attempts to redress the balance by upregulating catabolic processes, whilst concomitantly inhibiting anabolic processes. Despite its critical importance in the functioning of eukaryotic cells, there has been a paucity of studies investigating the potential for dysregulation of AMPK by viruses. Recently, however, there have been a number of reports that have begun to address this gap in our knowledge. In this article, we will review this emerging field, outlining how a variety of viruses have been shown to either stimulate or inhibit AMPK activity. We will also document the effects of these perturbations on the biology of virus infection, in particular with regard to the ability of viruses to persist or cause cytopathogenesis. Copyright © 2011 John Wiley & Sons, Ltd.
Viruses as key regulators of angiogenesis
Authors: Vrancken Kristof , Vervaeke Peter , Balzarini Jan , Liekens Sandra 
Published: April 2011

SUMMARYAngiogenesis is an important physiological process that is controlled by a precise balance of growth and inhibitory factors in healthy tissues. However, environmental and genetic factors may disturb this delicate balance, resulting in the development of angiogenic diseases, tumour growth and metastasis. During the past decades, extensive research has led to the identification and characterization of genes, proteins and signalling pathways that are involved in neovascularization. Moreover, increasing evidence indicates that viruses may also regulate angiogenesis either directly, by (i) producing viral chemokines, growth factors and/or receptors or (ii) activating blood vessels as a consequence of endothelial cell tropism, or indirectly, by (iii) modulating the activity of cellular proteins and/or (iv) inducing a local or systemic inflammatory response, thereby creating an angiogenic microenvironment. As such, viruses may modulate several signal transduction pathways involved in angiogenesis leading to changes in endothelial cell proliferation, migration, adhesion, vascular permeability and/or protease production. Here, we will review different mechanisms that may be applied by viruses to deregulate the angiogenic balance in healthy tissues and/or increase the angiogenic potential of tumours. Copyright © 2011 John Wiley & Sons, Ltd.
Anti‐windup strategy for reset control systems
Authors: Tarbouriech Sophie , Loquen Thomas , Prieur Christophe 
Published: April 2011

AbstractThis paper proposes an anti‐windup strategy to deal with stability and performance requirements for a class of hybrid systems, such as those including a reset controller and subject to input saturation. The computation of the anti‐windup compensator aiming at ensuring both ℒ︁2 input‐to‐state stability and internal stability of the closed‐loop system is carried out from the solution of matrix inequalities. Depending on the way chosen to describe reset rules, the conditions for designing the anti‐windup compensator are expressed through nonlinear matrix inequalities or linear matrix inequalities. Some optimization criteria in both cases are considered for the synthesis purpose: maximization of the ℒ︁2‐norm upper bound on the admissible disturbances for which the trajectories are assured to be bounded; minimization of the ℒ︁2‐gain of the disturbance to the system‐to‐be‐controlled output; and the maximization of an estimate of the domain of attraction of the origin. Copyright © 2011 John Wiley & Sons, Ltd.
A comparison of one‐class bag‐of‐words user behavior modeling techniques for masquerade detection
Authors: Salem Malek Ben , Stolfo Salvatore J. 
Published: April 2011

ABSTRACTA masquerade attack is a consequence of identity theft. In such attacks, the impostor impersonates a legitimate insider while performing illegitimate activities. These attacks are very hard to detect and can cause considerable damage to an organization. Prior work has focused on user command modeling to identify abnormal behavior indicative of impersonation. In this paper, we investigate the performance of two one‐class user behavior profiling techniques: one‐class Support Vector Machines (ocSVMs) and a Hellinger distance‐based user behavior profiling technique. Both techniques model bags of words or commands and do not model sequences of commands. We use both techniques for masquerade detection and compare the experimental results. The objective is to evaluate which modeling technique is most suitable for use in an operational monitoring system, hence our focus is on accuracy and operational performance characteristics. We show that one‐class SVMs are most practical for deployment in sensors developed for masquerade detection in the general case. We also show that for specific users whose profile fits the average user profile, one‐class SVMs may not be the best modeling approach. Such users pose a more serious threat since they may be easier to mimic. Copyright © 2011 John Wiley & Sons, Ltd.
Simple preparation routes for corrosion protection hybrid sol‐gel coatings on AA 2024
Authors: Wittmar A. , Caparrotti H. , Wittmar M. , Veith M. 
Published: April 2011

AbstractIn recent years, many hybrid inorganic‐organic systems have been proposed in order to replace the traditional conversion coatings on metals like aluminum, and some results have been promising. However, many proposed solutions are based on complicated processes which are not easy to be adapted to industrial scale. The aim of this study was to establish a simple process leading to the production of highly efficient corrosion protective hybrid sol‐gel coating systems for the aluminum alloys as replacement for the highly hazardous conventional chromate conversion coatings. Hybrid coatings have been realized by means of the sol‐gel process. CeO2 and ZnO have been introduced as dispersions of nanoparticles in the system and used as corrosion inhibitors. The aim of this work was to obtain pore‐free coatings with increased barrier properties using nanoparticles that possess the double function of pore fillers and corrosion inhibitors. The proposed processes led to coating materials with good adherence to the aluminum substrate and an extremely long life in the accelerated neutral salt spray test according to DIN ISO 9227. Electrochemical impedance spectroscopy approves these results by high impedance values in the low‐frequency region of the Bode plot. Copyright © 2011 John Wiley & Sons, Ltd.
Förster Resonance Energy Transfer in Quantum Dot–Dye‐Loaded Zeolite L Nanoassemblies
Authors: Ramachandra Srinidhi , Popovic′ Zoran D. , Schuermann Klaus C. , Cucinotta Fabio , Calzaferri Gion , De Cola Luisa 
Published: April 2011

AbstractNanoassemblies formed by coating a dye‐loaded zeolite L surface with CdSe/ZnS core/shell quantum dots (QDs) is described. A photoinduced energy transfer is observed from the excited QDs, which are on the surface of the zeolite crystals, to dye molecules (energy acceptors) encapsulated and aligned in the 1D channels of the aluminosilicate host. Steady‐state and time‐resolved spectroscopy and microscopy are used to quantify the Förster resonance energy transfer occurring through electronic transition dipole interactions between the QDs and the oxonine‐loaded zeolite L crystals. For the first time the energy transfer in artificial antenna systems based on quantum dots and molecules hosted in inert systems is described.
Nanostructuring Polymeric Materials by Templating Strategies
Authors: Knoll Wolfgang , Caminade Anne‐Marie , Char Kookheon , Duran Hatice , Feng Chuan Liang , Gitsas Antonis , Kim Dong Ha , Lau Aaron , Lazzara Thomas D. , Majoral Jean‐Pierre , Steinhart Martin , Yameen Basit , Zhong X. H. 
Published: April 2011

AbstractThis contribution summarizes efforts in designing, assembling/synthesizing, and structurally and functionally characterizing nanostructured materials using anodized aluminum oxide (AAO) as a thin‐film template. Optical waveguide spectroscopy, using a nanoporous template as the guiding structure, is a particularly powerful analytical tool. The layer‐by‐layer approach for the fabrication of multilayer assemblies is shown to allow the fabrication of nanotube arrays. In addition to using dendrimers as building blocks, semiconducting nanomaterial (e.g., quantum dot) hybrid architectures with very interesting photophysical properties can be assembled. These can be employed, for example, in biosensing applications. Other strategies for using the AAO layers as templates include the growth of polymeric nanorod arrays from different functional monomers, which, after the dissolution of the template, are still able to guide light. This opens up novel concepts for integrated optics platforms with nanostructured materials.
Micro‐/Nano‐engineered Cellular Responses for Soft Tissue Engineering and Biomedical Applications
Authors: Tay Chor Yong , Irvine Scott Alexander , Boey Freddy Y. C. , Tan Lay Poh , Venkatraman Subbu 
Published: April 2011

AbstractThe development of biomedical devices and reconstruction of functional ex vivo tissues often requires the need to fabricate biomimetic surfaces with features of sub‐micrometer precision. This can be achieved with the advancements in micro‐/nano‐engineering techniques, allowing researchers to manipulate a plethora of cellular behaviors at the cell–biomaterial interface. Systematic studies conducted on these 2D engineered surfaces have unraveled numerous novel findings that can potentially be integrated as part of the design consideration for future 2D and 3D biomaterials and will no doubt greatly benefit tissue engineering. In this review, recent developments detailing the use of micro‐/nano‐engineering techniques to direct cellular orientation and function pertinent to soft tissue engineering will be highlighted. Particularly, this article aims to provide valuable insights into distinctive cell interactions and reactions to controlled surfaces, which can be exploited to understand the mechanisms of cell growth on micro‐/nano‐engineered interfaces, and to harness this knowledge to optimize the performance of 3D artificial soft tissue grafts and biomedical applications.
Decreased fetal cardiac performance in the first trimester correlates with hyperglycemia in pregestational maternal diabetes
Authors: Turan S. , Turan O. M. , Miller J. , Harman C. , Reece E. A. , Baschat A. A. 
Published: April 2011

AbstractObjectiveIn‐vitroanimal studies suggest that high glucose levels impair fetal cardiac function early in gestation. We aimed to study whether evidence of first‐trimester myocardial dysfunction can be detected in fetuses of women with pregestational diabetes mellitus.MethodsWomen with diabetes mellitus underwent fetal echocardiography at 11–14 weeks' gestational age. In fetuses with normal anatomy, the cardiac preload, diastolic function, global myocardial performance and placental afterload were studied by Doppler of the ductus venosus (DV), mitral and tricuspid early/atrial (E/A) ratios, left and right ventricular myocardial performance index (MPI) and umbilical artery (UA) Doppler, respectively. Cases were matched for gestational age and UA and DV Doppler with controls that had no diabetes mellitus.ResultsSixty‐three singleton diabetic pregnancies were matched with 63 controls. Mean gestational age at enrollment was 12.6 (range, 11.1–13.6) weeks. Diabetic mothers had moderate to poor glycemic control (median (range) glycosylated hemoglobin A1 (HbA1c), 7.5 (5.1–12.7)%, and the HbA1c level was ≥ 7% in 37 (59%)). Fetuses of diabetic mothers exhibited worse measures of diastolic dysfunction: the isovolumetric relaxation time (IRT) was significantly prolonged (left ventricle: 36.9 ± 7.4 ms vs. 45.8 ± 6.8 ms; right ventricle: 35.6 ± 8 ms vs. 46.4 ± 7.3 ms,P< 0.0001 for both). The mitral E/A ratio was lower in diabetics (0.55 ± 0.06 vs. 0.51 ± 0.08,P= 0.03), and the global myocardial performance was lower in both ventricles (left ventricle MPI: 0.5 ± 0.08; right ventricle MPI: 0.52 ± 0.08,P= 0.03 andP< 0.0001, respectively). This lower global myocardial performance was caused by a prolonged myocardial relaxation time, which was most marked in diabetics with an HbA1c of ≥ 7% (P< 0.001 vs. controls for both ventricles). There were no significant correlations between cardiac Doppler parameters and DV, UA indices and fetal heart rate (P> 0.05 for all).ConclusionsFetuses of poorly controlled diabetic mothers demonstrate significant differences in first‐trimester diastolic myocardial function compared with non‐diabetic controls. The decrease in myocardial performance is more marked with increasing HbA1c and appears to be independent of preload and afterload. The ability to document these cardiac functional changes this early in pregnancy opens potential new avenues to understand the consequences of maternal glycemic status. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Prediction of intrauterine fetal death in small‐forgestational‐age fetuses: impact of including ultrasound biometry in customized models
Authors: Odibo A. O. , Cahill A. G. , Odibo L. , Roehl K. , Macones G. A. 
Published: April 2011

AbstractObjectiveCustomized growth charts derived from maternal demographic characteristics alone have been shown to improve the prediction of pregnancy complications compared to population growth curves. We sought to estimate the impact of adding ultrasound biometric parameters to the customized chart for the prediction of intrauterine fetal death (IUFD).MethodsA retrospective cohort study was undertaken using an ultrasound database including singleton pregnancies followed between 16 and 20 weeks' gestation. After exclusion of preterm births, congenital anomalies, multifetal pregnancies and stillbirths (excluded only from derivation samples), we identified 59 016 births, divided into derivation (34 832) and validation (24 184) samples. Coefficients for significant physiological and pathological variables affecting fetal growth were derived using backward stepwise multiple regression (Cust‐chart). The same process was repeated including second‐trimester biometric parameters: biparietal diameter, head circumference, femur length and abdominal circumference in the regression models (Cust‐plus‐USS‐chart). The association between small‐for‐gestational age < 10th centile (SGA) pregnancies, defined using the two customized charts or our population‐based growth chart (Pop‐chart) and IUFD, were compared. Statistical analyses including OR, 95% CI and screening accuracy using each chart were performed.ResultsThe derived coefficients for fetal growth are comparable to those of previously published series. Of 24 184 pregnancies in the validation sample, IUFD was seen in 169 (0.7%). The pregnancies identified as SGA were: 2482 (10.26%), 2499 (10.33%) and 2634 (10.89%) using the Cust‐chart, Cust‐plus‐USS‐chart and Pop‐chart, respectively. The OR (95% CI) for the association between SGA defined by the three charts and IUFD was: 7.0 (4.5–11), 6.5 (4.2–10.2) and 2.4 (1.6–3.6) according to the Cust‐chart, Cust‐plus‐USS‐chart and Pop‐chart, respectively. Screening efficiency for IUFD using both customized charts was similar, with both demonstrating a higher sensitivity compared with the Pop‐chart.ConclusionsCustomized charts are more efficient in identifying pregnancies at risk for IUFD compared with population‐based charts. However, adding second‐trimester ultrasound biometric parameters to the customized model does not improve the prediction of IUFD compared with using maternal characteristics only. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Early‐stage cervical cancer: agreement between ultrasound and histopathological findings with regard to tumor size and extent of local disease
Authors: Gaurilcikas A. , Vaitkiene D. , Cizauskas A. , Inciura A. , Svedas E. , Maciuleviciene R. , Di Legge A. , Ferrandina G. , Testa A. C. , Valentin L. 
Published: April 2011

AbstractObjectivesTo determine the agreement between ultrasound and histological examination of the cervix in patients with early stage cervical cancer with regard to tumor size and local extent of the disease.MethodsEighteen patients with histologically proven cervical cancer Stage IB1–IIA according to traditional clinical staging (FIGO 1988) who were scheduled for radical surgery underwent a standardized transvaginal ultrasound examination. The maximum tumor length, anteroposterior tumor diameter, tumor width, tumor area, depth of cervical stroma invasion, and the minimal thickness of tumor‐free cervical stroma on sagittal and transverse planes through the cervix were measured, and the local extent of the disease within the parametria and vagina were evaluated. The surgical specimens were examined using a specifically devised method of histopathological examination. The results of the ultrasound and histopathological examinations were compared.ResultsLimits of agreement were wide and the intraclass correlation coefficient (ICC) was low (0.51–0.58) for three of the four measurements taken to represent the minimal depth of tumor‐free cervical stroma, i.e. the results of the measurements taken posteriorly and laterally. However, the limits of agreement were narrower and the ICC values were higher (0.74–0.92) for the depth of cervical stroma invasion and for the tumor size measurements. Histological examination revealed parametrial cancer infiltration in four patients, which was detected during ultrasound examination, with no false‐positive results.ConclusionsTransvaginal sonography is acceptably accurate for evaluation of tumor size and depth of cervical stroma invasion in clinical practice. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.