bluuebunny/crossref_metadata_2025 huggingface dataset:
Implementation of an Intuitive Writing Interface and a Laparoscopic Robot for Gynaecological Laser Assisted Surgery
Authors: Tang H-W , Brussel H Van , Sloten J Vander , Reynaerts D , Koninckx P R
Published: July 2005

The research reported in this paper aims at applying the human handwriting skill to improve and facilitate the control of laser-assisted laparoscopic surgery operations performed by gynaecological surgeons. For the purpose, a laparoscopic robot was interfaced with a digitizing tablet. This interface, further called the intuitive writing interface (IWI), directly converts the hand trajectory, handwritten on the tablet, into an input signal to the robot. It replaces the traditional complex manipulations performed by the surgeon during manual laparoscopic surgery by natural handwriting. It provides the surgeon with an intuitive ‘what-you-draw-is-what-you-cut’ control facility by employing his/her familiar handwriting skills to control the laser ablation process accurately.

The system was successfully built and tested in vitro. Performance tests on the robot resulted in tracking errors in the order of 1 mm in the target plane at an ablation speed of 20 mm/s. The high accuracy of the system was successfully demonstrated by cutting characters 4 mm high on an apple. These results indicate that laser ablation performance is upgraded by the IWI to the accuracy levels of human handwriting, which is much higher than can be obtained with manual laser laparoscopy.

Safety features include the use of pen contact with the tablet as a safety switch, and back drivability in the robot joints for easy manual positioning and evacuation in case of emergency.
A Comparison of Ultrasonic and X-ray Methods for Imaging the Growth Plate
Authors: Han S-M , Kim S-H
Published: July 2005

The purpose of this study was to assess a systematic and scientific method for measuring children's growth development, in which the accuracy of the existing diagnostic method has not yet been concretely examined. The most popular method for diagnosis of children's growth is to analyse the opening degree of the growth plate in each joint by an X-ray image. However, the X-ray method has some disadvantages; it is impossible to measure the diagnosis of growth periodically and repeatedly due to the radiation problem. Hence, this study introduced a profile analysis and the algorithm of analysing the image of the growth plate using the broadband ultrasound attenuation (BUA) of calcaneus, to verify the possibility of using an alternative ultrasonic method harmless to the human body. The images of the growth plate in the proximal tibiae, phalanges, and calcanei of 269 children (7–16 years old) were obtained using X-ray. The image of the growth plate in the calcanei was also obtained from these children using ultrasound. The results showed that the time of the opening degree of the growth plate in each joint was almost consistent between X-ray and ultrasonic images. Also, the images of the growth plate measured using X-ray and ultrasound showed a high correlation. Therefore, it is expected that the algorithm of ultrasonic profile analysis introduced in this study can replace the existing X-ray method to measure the growth plate correctly.
Facile Nonsurfactant Route to Silica-based Bimodal Xerogels with Micro/Mesopores
Authors: Yang Dongjiang , Xu Yao , Zhai Shangru , Zheng Junlin , Li Junping , Wu Dong , Sun Yuhan
Published: July 2005

A simple and nonsurfactant synthesis pathway has been developed to prepare silica-based bimodal micro/mesoporous hybrids using mixed polymethylhydrosiloxane and tetraethyl orthosilicate as silica sources.
Induction of Optical Activity in Oligosilanes by Chiral Wrapping with β-1,3-Glucan (Schizophyllan)
Authors: Sanji Takanobu , Kato Nobu , Tanaka Masato
Published: July 2005

Linear oligosilanes form inclusion complexes with schizophyllan to induce a preferential helical conformation within the chiral environment constructed by wrapping with schizophyllan.
Sulfur-bridged Linkage of [Ni(thiolato)2(amine)2]-type Complexes with Linear Gold(I) Ions Assisted by Aurophilic Interaction
Authors: Konno Takumi , Usami Masafumi , Toyota Atsushi , Hirotsu Masakazu , Kawamoto Tatsuya
Published: July 2005

The reaction of [Ni(aet)2] (aet = −SCH2CH2NH2) with AuI in water gave a S-bridged NiII2AuI2 tetranuclear structure in [Au2{Ni(aet)}2]2+, while the corresponding reaction using [Ni(L)] (L = [−SCH2CH2N=C(CH3)–]2) led to the formation of a NiII4AuI4 octanuclear structure in [Au4{Ni(L)}4]4+. Their molecular structures exhibiting aurophilic interactions were established by X-ray crystallography.
Controlled Synthesis of Novel Chromium Nitride Dendritic and Bundle-like Nanocrystals via Solvent-free Route at Low Temperature
Authors: Luo Wei , Zheng Fei , Zhu Kun , Tian Xiaobo , Xie Yi
Published: July 2005

By controlling the supersaturation, cubic CrN with novel dendritic and bundle-like nanostructures was synthesized via the solvent-free reaction of CrCl3 and NaNH2 at 250 °C. On the basis of the characterization of the obtained products by XRD, XPS, TEM, HRTEM, and FESEM, the possible formation mechanism of CrN with different nanostructures is proposed here.
Synthesis of Well-dispersed CuI Nanoparticles from an Available Solution Precursor
Authors: Yang Yang , Liu Shuman , Kimura Keisaku
Published: July 2005

A convenient liquid-phase route was proposed to synthesize well-dispersed CuI nanoparticles from Cu+–DMF solution precursor, which was prepared by dissolving bulk CuI in DMF. When water was gradually added, nanoscaled CuI was produced through the decomposition of the complex formed in this solution. A passivation layer of Cu+–DMF adsorbed on the particle surface was suggested to be responsible for the nanoparticle formation.
A Novel Diterpenoid from Euphorbia fischeriana
Authors: Wang Yu-Bo , Yao Guang-Min , Wang Hong-Bing , Qin Guo-Wei
Published: July 2005

Langduin D, a novel modified ent-abietane diterpenoid with an arylphloroglucinol moiety was isolated from the roots of Euphorbia fischeriana. Its structure was established by spectral data and confirmed by X-ray crystallography.
Global Village or Cyber-Balkans? Modeling and Measuring the Integration of Electronic Communities
Authors: Van Alstyne Marshall , Brynjolfsson Erik
Published: July 2005

Information technology can link geographically separated people and help them locate interesting or useful resources. These attributes have the potential to bridge gaps and unite communities. Paradoxically, they also have the potential to fragment interaction and divide groups. Advances in technology can make it easier for people to spend more time on special interests and to screen out unwanted contact. Geographic boundaries can thus be supplanted by boundaries on other dimensions. This paper formally defines a precise set of measures of information integration and develops a model of individual knowledge profiles and community affiliation. These factors suggest specific conditions under which improved access, search, and screening can either integrate or fragment interaction on various dimensions. As IT capabilities continue to improve, preferences—not geography or technology—become the key determinants of community boundaries.
Treatment Errors in Healthcare: A Safety Climate Approach
Authors: Naveh Eitan , Katz-Navon Tal , Stern Zvi
Published: July 2005

Recent reports on patient safety in healthcare point to the high frequency of treatment errors. This study suggests a new theory of safety climate and brings empirical evidence that helps explain the occurrence of treatment errors. Four safety climate dimensions have been identified. They include employee perceptions of the suitability of the organization’s safety procedures for their daily work, employee perceptions of the frequency and the clarity of the safety information distributed by the organization, the way employees interpret their managers’ safety practices, and the perceived priority given to safety within the organization. The study was conducted in 21 medical units in a general hospital and the results were cross-validated in 15 units in another hospital. Results demonstrated that perceived suitable safety procedures and frequent and clear information flow reduced treatment errors only when managers practiced safety and through their influence on the level of priority given to safety within the unit. Implications for safety climate theory and for reducing the occurrence of treatment errors by safety interventions are discussed.
Measuring Customer Relationships: The Case of the Retail Banking Industry
Authors: Nagar Venky , Rajan Madhav V.
Published: July 2005

Arguing that GAAP is ill suited for estimating the future profitability of intangibles, the accounting literature (e.g., Kaplan and Norton 1996, Lev 2001) has recently proposed alternative measurement models. These models view intangibles as composed of a set of fundamental business activities and use multiple financial and nonfinancial metrics causally interlinked to profits to represent this view. Using a unique and proprietary cross-sectional data set of the retail banking industry, we provide some of the first tests on the empirical validity of such measurement models. We characterize the core deposit intangible, an important retail banking intangible representing a bank’s relationships with its customers, using financial and nonfinancial metrics on price, service, customer usage, and customer satisfaction. We find that the metrics do not individually predict future earnings, but gain individual significance in a collective setting, increasing the predictive power substantially. We argue that this result occurs because the activities underlying the measures are causally interlinked to profits and explicitly illustrate these linkages with a structural path model. Our measurement model also predicts significant interactive effects in the way our measures are informative about future profits, and we document such effects, not just among the individual measures, but also across the measures and environmental factors such as the bank’s strategy. In sum, our measurement model illustrates the key drivers, measures, and interactions in retail banking customer relationships.
Corporate Disclosure and Operational Strategy: Financial vs. Operational Success
Authors: Ozbilgin Mehmet , Penno Mark
Published: July 2005

We introduce a simple game between two rival firms—a leader and a follower, where the leader moves first and makes an operational choice under uncertainty. The leader’s disclosure of its resulting financial success or failure may in turn give the follower a competitive advantage by informing its operational choice. When this occurs, the leader reacts by sometimes making an operational choice that it knows to be less likely to produce operational success than the alternative. This makes the financial report less useful to the follower and expected financial success more likely for the leader. Alternatively, when the financial report does not provide useful information to the follower (e.g., the financial report aggregates many activities in addition to the activity the follower is interested in), it may be the follower rather than the leader who makes the choice less likely to be operationally successful. We document that when trading off operational success for financial success, the leader’s aim is operational unpredictability, while the follower’s aim is coordination. As such, this paper highlights the intricate interplay between internal operational decisions, public inferences concerning those decisions, and different forms of success under intense competition.
Detecting Regime Shifts: The Causes of Under- and Overreaction
Authors: Massey Cade , Wu George
Published: July 2005

Many decision makers operate in dynamic environments in which markets, competitors, and technology change regularly. The ability to detect and respond to these regime shifts is critical for economic success. We conduct three experiments to test how effective individuals are at detecting such regime shifts. Specifically, we investigate when individuals are most likely to underreact to change and when they are most likely to overreact to it. We develop a system-neglect hypothesis: Individuals react primarily to the signals they observe and secondarily to the environmental system that produced the signal. The experiments, two involving probability estimation and one involving prediction, reveal a behavioral pattern consistent with our system-neglect hypothesis: Underreaction is most common in unstable environments with precise signals, and overreaction is most common in stable environments with noisy signals. We test this pattern formally in a statistical comparison of the Bayesian model with a parametric specification of the system-neglect model.
A Fictitious Play Approach to Large-Scale Optimization
Authors: Lambert Theodore J. , Epelman Marina A. , Smith Robert L.
Published: July 2005

In this paper, we investigate the properties of the sampled version of the fictitious play algorithm, familiar from game theory, for games with identical payoffs, and propose a heuristic based on fictitious play as a solution procedure for discrete optimization problems of the form max{u(y): y = (y1,…,yn) ∈ 𝒴1×⋯×𝒴n}, i.e., in which the feasible region is a Cartesian product of finite sets 𝒴i, i ∈ N = {1,…,n}. The contributions of this paper are twofold. In the first part of the paper, we broaden the existing results on convergence properties of the fictitious play algorithm on games with identical payoffs to include an approximate fictitious play algorithm that allows for errors in players’ best replies. Moreover, we introduce sampling-based approximate fictitious play that possesses the above convergence properties, and at the same time provides a computationally efficient method for implementing fictitious play. In the second part of the paper, we motivate the use of algorithms based on sampled fictitious play to solve optimization problems in the above form with particular focus on the problems in which the objective function u(·) comes from a “black box,” such as a simulation model, where significant computational effort is required for each function evaluation.
A Multiperiod Dynamic Model of Taxi Services with Endogenous Service Intensity
Authors: Yang Hai , Ye Min , Tang Wilson Hon-Chung , Wong Sze Chun
Published: July 2005

This paper presents a spatially aggregated multiperiod taxi service model with endogenous service intensity. The whole day service period is divided into a number of subperiods; during each subperiod, taxi supply and customer demand characteristics are assumed to be uniform. Customer demand is period-specific and described as a function of waiting time and taxi fare. Taxi operating cost for each work shift consists of two components: one component a function of total service time and the other component period-dependent. Each taxi driver can work for one or more shifts each day and freely chooses the starting and ending time of each shift. Equilibrium of taxi services is obtained when taxi drivers cannot increase their individual profits by changing their individual working schedules. A novel clock network representation is proposed to characterize the multiperiod taxi service equilibrium problem. The problem of interest is formulated as a network equilibrium model with path-specific costs and arc-capacity constraints, which can be solved using conventional nonlinear network flow optimization methods. The proposed model can ascertain at equilibrium the service intensity and utilization rate of taxis and the level of service quality throughout the day. The information obtained is useful for the prediction of the effects of alternative government regulations on the equilibrium of demand and supply in the urban taxi industry.
Discrete-Time Financial Planning Models Under Loss-Averse Preferences
Authors: Siegmann Arjen , Lucas André
Published: July 2005

We consider a dynamic asset allocation problem formulated as a mean-shortfall model in discrete time. A characterization of the solution is derived analytically under general distributional assumptions for serially independent risky returns. The solution displays risk taking under shortfall, as well as a specific form of time diversification. Also, for a representative stock-return distribution, risk taking increases monotonically with the number of decision moments given a fixed horizon. This is related to the well-known casino effect arising in a downside-risk and expected return framework. As a robustness check, we provide results for a modified objective with a quadratic penalty on shortfall. An analytical solution for a single-stage setup is derived, and numerical results for the two-period model and time diversification are provided.
Fitting Time-Series Input Processes for Simulation
Authors: Biller Bahar , Nelson Barry L.
Published: July 2005

Providing accurate and automated input-modeling support is one of the challenging problems in the application of computer simulation of stochastic systems. The models incorporated in current input-modeling software packages often fall short because they assume independent and identically distributed processes, even though dependent time-series input processes occur naturally in the simulation of many real-life systems. Therefore, this paper introduces a statistical methodology for fitting stochastic models to dependent time-series input processes. Specifically, an automated and statistically valid algorithm is presented to fit autoregressive-to-anything (ARTA) processes with marginal distributions from the Johnson translation system to stationary univariate time-series data. ARTA processes are particularly well suited to driving stochastic simulations. The use of this algorithm is illustrated with examples.
Resource Flexibility with Responsive Pricing
Authors: Chod Jiri , Rudi Nils
Published: July 2005

This article studies two types of flexibility used by firms to better respond to uncertain market conditions: resource flexibility and responsive pricing. We consider a situation in which a single flexible resource can be used to satisfy two distinct demand classes. While the resource capacity must be decided based on uncertain demand functions, the resource allocation as well as the pricing decision are made based on the realized demand functions.

We characterize the effects of two key drivers of flexibility: demand variability and demand correlation, assuming normally distributed demand curve intercepts. Demand variability creates opportunity costs and, with fixed prices, decreases the firm’s profit. We show that with the additional flexibility gained from responsive pricing, the firm can maximize the benefits of favorable demand conditions and mitigate the effects of poor demand conditions, ultimately profiting from variability. Positive demand correlation, on the other hand, remains undesirable under responsive pricing. The optimal capacity of the flexible resource is always increasing in both demand variability and demand correlation. This contrasts with the scenarios based on fixed prices, highlighting the crucial difference that responsive pricing makes in the management of flexible resources. We further quantify the value of flexibility for the firm and its customers by considering, as a benchmark, a firm relying on two dedicated resources. The value of flexibility is most significant if the demand levels are highly variable and negatively correlated. In such cases, the firm benefits from demand variability due to responsive pricing, while facing limited demand risk due to resource flexibility. Finally, we endogenize the input price of the flexible resource by considering the pricing decision of the resource supplier.
Genetic evidence for the Mongolian ancestry of Kalmyks
Authors: Nasidze Ivan , Quinque Dominique , Dupanloup Isabelle , Cordaux Richard , Kokshunova Lyudmila , Stoneking Mark
Published: July 2005

The Kalmyks are an ethnic group along the lower Volga River in Russia who are thought to have migrated there from Mongolia about 300 years ago. To investigate their origins, we studied mtDNA and Y‐chromosome variation in 99 Kalmyks. Both mtDNA HV1 sequences and Y‐chromosome SNP haplogroups indicate a close relationship of Kalmyks with Mongolians. In addition, genetic diversity for both mtDNA and the Y chromosome are comparable in Kalmyks, Mongolians, and other Central Asian groups, indicating that the Kalmyk migration was not associated with a substantial bottleneck. The so‐called “Genghis Khan” Y‐chromosome short tandem repeat (STR) haplotype was found in high frequency (31.3%) among Kalmyks, further supporting a strong genetic connection between Kalmyks and Mongolians. Genetic analyses of even recent, relatively well‐documented migrations such as of the Kalmyks can therefore lead to new insights concerning such migrations. Am J Phys Anthropol 126:, 2005. © 2005 Wiley‐Liss, Inc.
Ion Binding to Bilayers of the Iridescent Phase in Aqueous Tetradecyldimethylaminoxid Studied by Mass Spectrometry
Authors: Jakubowska Anna
Published: July 2005

The behaviour of a tetradecyldimethylaminoxid (C14DMAO) iridescent solution with a strict composition has been investigated in the presence of NaCl, KCl, NaF, KF, NaClO4, or NH4ClO4 at a constant ionic strength. Specific ion effects (the Hofmeister effects), arising when changing ions of the same valency, have been studied. The interactions of C14DMAO molecules with the added ions have been investigated by electrospray ionisation mass spectrometry (ESI‐MS). The ESI‐MS results indicate that C14DMAO bilayer interactions are stronger with cations than with anions. Among the cations studied here, potassium ions are more favourably bound at the C14DMAO bilayers than sodium ions. The aminoxide groups of the C14DMAO molecules do not bind NH4+ ions. The positive charge of the electric double layers on the C14DMAO bilayers is neutralised by anions of the added electrolytes. Consequently, the separation distance between the lamellar layers decreases and the ordering in the studied systems is broken. Among the studied counterions, chloride ions are most strongly bound to the interface causing the greatest breakdown of the ordering in the iridescent solution.
Molecular cloning and developmental expression of foxP2 in zebrafish
Authors: Bonkowsky Joshua L. , Chien Chi‐Bin
Published: July 2005

Forkhead domain transcription factors are a large gene family with multiple roles in development. FOXP2, a recently identified member of this family, has been shown to be critical for normal development of language in humans, but little is known of its broader function during nervous system development. We report here the cloning of foxP2, the zebrafish ortholog of FOXP2. Zebrafish FoxP2 is highly conserved in its zinc‐finger and forkhead domains, but lacks the large glutamine repeat characteristic of its orthologs. In examining the spatial and temporal distribution of foxP2 during development, we find that it is specifically expressed in many domains of the nervous system, including the telencephalon, diencephalon, cerebellum, hindbrain, tectum, retinal ganglion cells, and spinal cord. Thus, in addition to specific roles in language development, foxP2 likely has a more general conserved role in nervous system development. Developmental Dynamics 234:740–746, 2005. © 2005 Wiley‐Liss, Inc.
Regulation of melanoblast and retinal pigment epithelium development by Xenopus laevis Mitf
Authors: Kumasaka Mayuko , Sato Shigeru , Yajima Ichiro , Goding Colin R. , Yamamoto Hiroaki
Published: July 2005

Mitf is a central regulator of pigment cell development that is essential for the normal development of the melanocyte and retinal pigment epithelium (RPE) lineages. To understand better the role of Mitf, we have used the Xenopus laevis experimental system to allow a rapid examination of the role of Mitf in vivo. Here, we report the function of XlMitfα‐M on melanophore development and melanization compared with that of Slug that is expressed in neural crest cells. Overexpression of XlMitfα‐M led to an increase in melanophores that was partly contributed by an increase in Slug‐positive cells, indicating that XlMitfα‐M is a key regulator of melanocyte/melanophore development and melanization. Moreover, overexpression of a dominant‐negative form of XlMitfα led to a decrease in the number of melanophores and induced abnormal melanoblast migration. We also observed an induction of ectopic RPE and extended RPE by overexpression of XlMitfα‐M and possible interactions between XlMitfα and several eye‐related genes essential for normal eye development. Developmental Dynamics 234:523–534, 2005. © 2005 Wiley‐Liss, Inc.
Blind deconvolution using TV regularization and Bregman iteration
Authors: He Lin , Marquina Antonio , Osher Stanley J.
Published: July 2005

In this paper we formulate a new time dependent model for blind deconvolution based on a constrained variational model that uses the sum of the total variation norms of the signal and the kernel as a regularizing functional. We incorporate mass conservation and the nonnegativity of the kernel and the signal as additional constraints. We apply the idea of Bregman iterative regularization, first used for image restoration by Osher and colleagues [S.J. Osher, M. Burger, D. Goldfarb, J.J. Xu, and W. Yin, An iterated regularization method for total variation based on image restoration, UCLA CAM Report, 04‐13, (2004)]. to recover finer scales. We also present an analytical study of the model discussing uniqueness of the solution, convergence to steady state and a priori parameter estimation. We present a simple algorithmic implementation of the model and we perform a series of numerical experiments to show evidence of the good behavior of the numerical scheme and quality of the results, improving on results obtained by Chan and Wang [T.F. Chan and C.K. Wong, Total variation blind deconvolution, IEEE Trans Image Process 7 (1998), 370–375]. © 2005 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 15, 74–83, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20040
Simultaneous total variation image inpainting and blind deconvolution
Authors: Chan Tony F. , Yip Andy M. , Park Frederick E.
Published: July 2005

We propose a total variation based model for simultaneous image inpainting and blind deconvolution. We demonstrate that the tasks are inherently coupled together and that solving them individually will lead to poor results. The main advantages of our model are that (i) boundary conditions for deconvolution required near the interface between observed and occluded regions are naturally generated through inpainting; (ii) inpainting results are enhanced through deconvolution (as opposed to inpainting blurry images). As a result, ringing effects due to imposing improper boundary conditions and errors due to imperfection of inpainting blurry images are reduced. Moreover, our model can also be used to generate boundary conditions for regular deconvolution problems that yields better results than previous methods.© 2005 Wiley Periodicals, Inc. © 2005 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 15, 92–102, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20041
Synthetic scaffold morphology controls human dermal connective tissue formation
Authors: Wang Hongjun , Pieper Jeroen , Péters Fabienne , van Blitterswijk Clemens A. , Lamme Evert N.
Published: July 2005

Engineering tissues in bioreactors is often hampered by disproportionate tissue formation at the surface of scaffolds. This hinders nutrient flow and retards cell proliferation and tissue formation inside the scaffold. The objective of this study was to optimize scaffold morphology to prevent this from happening and to determine the optimal scaffold geometric values for connective tissue engineering. After comparing lyophilized crosslinked collagen, compression molded/salt leached PEGT/PBT copolymer and collagen‐PEGT/PBT hybrid scaffolds, the PEGT/PBT scaffold was selected for optimization. Geometric parameters were determined using SEM, microcomputed tomography, and flow permeability measurements. Fibroblast were seeded and cultured under dynamic flow conditions for 2 weeks. Cell numbers were determined using CyQuant DNA assay, and tissue distribution was visualized in H&E‐ and Sirius Red‐stained sections. Scaffolds 0.5 and 1.5 mm thick showed bridged connected tissue from top‐to‐bottom, whereas 4‐mm‐thick scaffolds only revealed tissue ingrowth until a maximum depth of 0.6–0.8 mm. Rapid prototyped scaffold were used to assess the maximal void space (pore size) that still could be filled with tissue. Tissue bridging between fibers was only found at fiber distances ≤401 ± 60 μm, whereas filling of void spaces in 3D‐deposited scaffolds only occurred at distances ≤273 ± 55 μm. PEGT/PBT scaffolds having similar optimal porosities, but different average interconnected pore sizes of 142 ± 50, 160 ± 56 to 191 ± 69 μm showed comparable seeding efficiencies at day 1, but after 2 weeks the total cell numbers were significantly higher in the scaffolds with intermediate and high interconnectivity. However, only scaffolds with an intermediate interconnectivity revealed homogenous tissue formation throughout the scaffold with complete filling of all pores. In conclusion, significant amount of connective tissue was formed within 14 days using a dynamic culture process that filled all void spaces of a PEGT/PBT scaffolds with the following geometric parameters: thickness 1.5–1.6 mm, pore size range 90–360 μm, and average interconnecting pore size of 160 ± 56 μm. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Theoretical study of quinolines–I2 intermolecular interaction and implications on dye‐sensitized solar cell performance
Authors: Kusama Hitoshi , Sugihara Hideki
Published: July 2005

The monomer and intermolecular charge‐transfer complexes of 13 different quinoline derivatives with diiodine were studied using ab initio molecular orbital (MO) and density functional theory (DFT) methods. Calculations revealed that the σ* orbital of iodine interacts with the nitrogen lone pair in the quinoline ring. The open‐circuit photovoltage (Voc) values of an Ru(II) complex dye‐sensitized nanocrystalline TiO2 solar cell with an I−/I redox electrolyte in acetonitrile using quinoline additives were compared to the computational calculations on the intermolecular interaction between quinolines and I2. The optimized geometries, frequency analyses, Mulliken population analyses, natural bond orbital (NBO) analyses, and interaction energies indicate that the Voc value of the solar cell is higher when quinoline complexes more favorably interact with I2. Therefore, the interaction between the quinoline additives and iodine redox electrolyte is an important factor for controlling dye‐sensitized solar cell performance. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1372–1382, 2005
Genomic sequence correction by single‐stranded DNA oligonucleotides: role of DNA synthesis and chemical modifications of the oligonucleotide ends
Authors: Olsen Petter Angell , Randøl Markus , Luna Luisa , Brown Tom , Krauss Stefan
Published: July 2005

Background

Single‐stranded oligonucleotides (ssODN) can induce site‐specific genetic alterations in selected mammalian cells, but the involved mechanisms are not known.

Methods

We corroborate the potential of genomic sequence correction by ssODN using chromosomally integrated mutated enhanced green fluorescent protein (mEGFP) reporter genes in CHO cell lines. The role of integration site was studied in a panel of cell clones with randomly integrated reporters and in cell lines with site‐specific single copy integration of the mEGFP reporter in opposite orientations. Involvement of end modification was examined on ssODN with unprotected or phosphorothioate (PS) protected ends. Also ssODN containing octyl or hexaethylene glycol (HEG) end blocking groups were tested. The significance of DNA synthesis was investigated by cell cycle analysis and by the DNA polymerases α, δ and ε inhibitor aphidicolin.

Results

Correction rates of up to 5% were observed upon a single transfection of ssODN. Independent of the mEGFP chromosomal integration site and of its orientation towards the replication fork, antisense ssODN were more effective than sense ssODN. When ssODN ends were blocked by either octyl or HEG groups, correction rates were reduced. Finally, we demonstrate a dependence of the process on DNA synthesis.

Conclusions

We show that, on a chromosomal level, the orientation of the replication fork towards the targeted locus is not central in the strand bias of ssODN‐based targeted sequence correction. We demonstrate the importance of accessible ssODN ends for sequence alteration. Finally, we provide evidence for the involvement of DNA synthesis in the process. Copyright © 2005 John Wiley & Sons, Ltd.
Osteoporosis is associated with increased marrow fat content and decreased marrow fat unsaturation: A proton MR spectroscopy study
Authors: Yeung David K.W. , Griffith James F. , Antonio Gregory E. , Lee Francis K.H. , Woo Jean , Leung Ping C.
Published: July 2005

Purpose

To use proton magnetic resonance spectroscopy (1H‐MRS) to evaluate vertebral marrow fat, and to determine whether bone density correlates with fat content and fat unsaturation levels in postmenopausal women.

Materials and Methods

Fifty‐three women (mean age = 70 years) underwent dual energy x‐ray absorptiometry and 1H‐MRS, and 12 young female controls (mean age = 28 years) underwent 1H‐MRS of the lumber spine. Water and lipid peak amplitudes were measured to calculate fat content and fat unsaturation index. Spearman's correlation tests and a t‐test comparison of means were applied.

Results

1H‐MRS was successful in 15 normal, 15 osteopenic, and 20 osteoporotic subjects, and in all controls. Marrow fat content was significantly elevated in osteoporotic (65.5% ± 10%) and osteopenic (63.5% ± 9.3%) subjects compared to normal subjects (56.3% ± 11.2%) and young controls (29% ± 9.6%). The fat unsaturation index was significantly decreased in osteoporotic (0.091 ± 0.013) and osteopenic (0.097 ± 0.014) subjects compared to normal subjects (0.114 ± 0.016) and young controls (0.127 ± 0.031). A good inverse correlation was observed between the fat content and the unsaturation index (rs = −0.53, P < 0.0001).

Conclusion

Osteoporosis is associated with increased marrow fat. As marrow fat increases, saturated lipids appear to increase preferentially to unsaturated lipids. J. Magn. Reson. Imaging 2005;22:279–285. © 2005 Wiley‐Liss, Inc.
Pathology‐guided MR analysis of acute and chronic experimental allergic encephalomyelitis spinal cord lesions at 1.5T
Authors: Cook Lisa L. , Foster Paula J. , Karlik Stephen J.
Published: July 2005

Purpose

To directly correlate spinal cord pathology of guinea pigs with experimental allergic encephalomyelitis (EAE) to the MRI data obtained at 1.5T.

Materials and Methods

Spinal cords from EAE animals were imaged in vivo with the following MRI sequences: T2‐FSE, PD‐FSE, fluid‐attenuated inversion recovery (FLAIR)‐FSE, T2‐CSE, T1‐CSE, T1‐CSE + gadolinium‐DTPA (Gd‐DTPA), PD‐CSE, and short‐tau inversion recovery (STIR)‐FSE. The spinal cords were removed and the lesions with specific pathological compositions were identified by histological analysis. Regions of interest (ROIs) were drawn on the corresponding MR images, and signal‐to‐noise ratios (SNRs) were measured for each MR sequence and compared with controls.

Results

The receiver operating characteristic (ROC) analysis of STIR‐FSE and PD‐CSE was able to differentiate tissue that contained cellular infiltrates with a high degree of accuracy. The SNRs of T2‐FSE, STIR‐FSE, T2‐CSE, PD‐CSE, and T1‐CSE + Gd‐DTPA were elevated in lesions that contained cellular infiltrates alone, whereas the SNRs of PD‐CSE and T1‐CSE + Gd‐DTPA were reduced in demyelinated lesions that also contained inflammation.

Conclusion

The SNR difference between the two lesion groups suggests that the combination of STIR‐FSE, PD‐CSE, and T1‐CSE + Gd‐DTPA sequences may be useful for differentiating inflammatory lesions containing demyelination from lesions with inflammation alone. J. Magn. Reson. Imaging 2005;22:180–188. © 2005 Wiley‐Liss, Inc.
High‐resolution anatomic, diffusion tensor, and magnetization transfer magnetic resonance imaging of the optic chiasm at 3T
Authors: Vinogradov Elena , Degenhardt Alexandra , Smith Derek , Marquis Robert , Vartanian Timothy K. , Kinkel Philip , Maier Stephan E. , Hackney David B. , Lenkinski Robert E.
Published: July 2005

Purpose

To evaluate techniques for anatomical and physiological imaging of the intracranial optic nerve (ON), optic chiasm (OC), and optic tract (OT) at 3T with the aim of visualizing axonal damage in multiple sclerosis (MS).

Materials and Methods

Imaging was performed on a 3T scanner employing a custom‐designed head coil that consisted of a coil array with four coils (30 × 30 cm2). Oblique fast spin echo (FSE) images, magnetization transfer (MT)‐enhanced 3D gradient‐echo (GRE) time‐of‐flight (TOF) images, and line scan diffusion images (LSDI) were obtained. Full diffusion tensor (DT) analysis was performed, and apparent diffusion coefficient (ADC), fractional anisotropy (FA), and fiber direction maps were obtained.

Results

FSE anatomic images were obtained with an in‐plane resolution of 0.39 × 0.52 mm2. The in‐plane resolution of the MT and LSDI images was 0.78 × 0.78 mm2. The OC, intracranial ON, and OT can be seen on these images. The dominant fiber orientations in the OC, ON, and OT, as derived from the DT images, are displayed.

Conclusion

This study shows that by using 3T and a custom‐designed, four‐channel head coil, it is possible to acquire high‐resolution anatomical and physiological images of the OC, ON, and OT. The pilot results presented here pave the way for imaging the anterior visual pathway in patients with MS. J. Magn. Reson. Imaging 2005;22:302–306. © 2005 Wiley‐Liss, Inc.
Hepatocellular adenomas in men: MRI findings in four patients
Authors: Psatha Evlampia A. , Semelka Richard C. , Armao Diane , Woosley John T. , Firat Zeynep , Schneider Guenther
Published: July 2005

Purpose

To demonstrate both MRI and histopathological findings of hepatocellular adenomas (HCAs) in men.

Materials and Methods

HCAs in four men are reported. All patients underwent MR studies at 1.5T including serial gadolinium‐enhanced gradient echo imaging.

Results

Three men had solitary non‐hemorrhagic adenomas that exhibited a uniform capillary blush with no central scar, and uniform fading of the tumor to near isointensity with the liver parenchyma by one minute. One of the subjects had uniform fat content as shown by uniform low signal on out‐of‐phase images. One patient had a solitary hemorrhagic adenoma that measured 17 cm in diameter and was heterogeneous on all sequences. Two of the four patients had a history of anabolic steroid use, and in the other two patients no underlying explanation for the tumor was found.

Conclusions

Although three of the four patients had tumors that exhibited uniform homogeneous tumor blush and rapid fading of enhancement, because HCAs are rare in men and resemble hepatocellular carcinoma (HCC) in appearance, our findings suggest that histological confirmation of HCAs may not be avoidable in men. J. Magn. Reson. Imaging 2005;22:258–264. © 2005 Wiley‐Liss, Inc.
Multislice continuous arterial spin‐labeled perfusion MRI in patients with chronic occlusive cerebrovascular disease: A correlative study with CO2 PET validation
Authors: Kimura Hirohiko , Kado Hirotsugu , Koshimoto Yoshio , Tsuchida Tatsurou , Yonekura Yoshiharu , Itoh Harumi
Published: July 2005

Purpose

To compare the use of multislice continuous arterial spin labeling (CASL) and CO2 positron emission tomography (PET) to assess CBF in patients with chronic occlusive cerebrovascular disease for the validation of quantitative CASL perfusion in an altered hemodynamic state.

Materials and Methods

Eleven patients with occlusive carotid artery disease were studied with CASL and conventional MRI. Cerebral blood flow (CBF) was also measured with O15‐labeled CO2 gas using a whole‐body PET scanner. The average values within region of interests (ROIs) drawn on coregistered CASL and PET images were used for the linear regression analysis and to assess the effect of transit time on the quantification using CASL.

Result

In all patients there was a significant correlation between the CBF values from CASL and PET (r = 0.71 ± 0.07, P < 0.001). The slope of regression lines varied widely among patients (0.54–1.77). Longer transit times were estimated in four of 11 patients in the hypoperfusion region.

Conclusion

Quantification of CBF using CASL is feasible and reasonable, even when employed in a routine clinical setting. However, the long transit time may lead to underestimation of the affected side in occlusive cerebrovascular disease. J. Magn. Reson. Imaging 2005;22:189–198. © 2005 Wiley‐Liss, Inc.
Biodegradation study of crop residues as affected by exogenous inorganic nitrogen and fungal inoculants
Authors: Gaind Sunita , Pandey Alok Kumar , Lata
Published: July 2005

The comparative decomposition of chickpea residue, and chopped and unchopped wheat straw was investigated in pits for 120 days. Microbial biomass, humus, C/N ratio, pH, Electrical conductivity (EC), dehydrogenase, alkaline phosphatase, cellulase, xylanase, total phenol and soluble protein were determined to assess their response to the addition of inorganic nitrogen and mixed fungal inoculum of Aspergillus nidulans, Phanerochaete chrysosporium and Trichoderma viride. The evaluation of physico‐chemical parameters (organic matter, organic carbon, N, C/N, pH, EC, microbial biomass) revealed that by supplementing unchopped wheat straw with 1% urea and mixed fungal inoculum, a lowest C/N ratio of 10.7, lowest biomass of 9.54 and highest humus content of 13% can be achieved within 3 months. Germination of Lepidium sativum (cress seeds) showed a germination index >60%, in this treatment. The enzyme assay for dehydrogenase indicated highest microbial activity in uninoculated treatments compared to fungal inoculated counterparts, in the second month sampling (active phase of composting). However, cellulase and xylanase activity showed an upward trend during curing phase of composting. Chickpea residue compost, though resulted in a C/N ratio of 17.3, but its germination index was less than 60%. The rapid quality tests conducted for H2S, NH3, NO3 and starch confirmed the stability and maturity of finished compost prepared from wheat straw through microbial inoculants. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A positive association of peripheral arterial occlusive disease (PAD) and Chlamydophila (Clamydia) pneumoniae
Authors: Fernández F. , Gutiérrez J. , Linares J. , Rojas A. , Sorlózano A.
Published: July 2005

The relationship between Chlamydophila pneumoniae (Cp) infection and peripheral arterial occlusive disease (PAD) was studied by analyzing clinical samples from 95 patients with PAD and 100 controls. The following investigations were conducted: IgG and IgA against lipopolysaccharide (LPS) and against purified Cp‐specific antigens from elementary bodies (EB) with ELISA; anti‐EB IgG, with MIF; Cp DNA in arterial biopsy and peripheral blood mononuclear cells with heminested PCR; LPS with ELISA; and bacteria culture in HEp‐2 cells from arterial biopsy. A significantly higher ratio of anti‐EB IgG was detected in patients. There were no significant differences in anti‐LPS IgG, anti‐LPS IgA and anti‐EB IgA between cases and controls. Cp DNA findings in the vascular wall biopsy showed significant differences between cases and controls. We obtained results that significantly involve Cp infection with PAD through the detection of anti‐EB IgG from serum and bacterial DNA from arterial biopsy. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Selection of bacteria and plant seeds for potential use in the remediation of diesel contaminated soils
Authors: AlGhazawi Ziad , Saadoun Ismail , AlShak'ah Abdalla
Published: July 2005

Enumeration and recovery of the dominant bacteria from a chronically fuel contaminated soil has been investigated. Bacterial counts from these polluted soils ranged between 0.70 × 108 and 28.20 × 108 CFU/g soil. Three different types of bacterial colonies have been recovered on the agar plates. Biochemical examination of the recovered bacteria revealed that they mainly belonged to the genus Pseudomonas, Micrococcus and Bacillus. Turbidity, cell biomass (dry weight basis), and physical appearance determined the growth of these bacteria on diesel. A noticeable decline in alfalfa (Medicago sativa) seeds germination of 15–30% was shown at 500 mg/kg diesel or higher. Under these contaminated conditions, fescue grass (Cyndon dactylon) exhibited a higher viability than alfalfa indicating that C. dactylon seeds are relatively tolerant to diesel and can possibly be used in phytoremediation of diesel contaminated soils. Results of diesel phyotoxicity to seed germination of these two plants were based on filter paper media and therefore; should be considered as first indication only. Extrapolation of such results to actual soil conditions should be catiously approached taking into account diesel sorption on soil and mechanisms of its bioavailability. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microfungi in cultivated fields in Eskişehir provience (Turkey)
Authors: Demirel Rasime , Ilhan Semra , Asan Ahmet , Kinaci Engin , Oner Setenay
Published: July 2005

The soil microfungi flora was investigated in four locations of Eskişehir (Turkey). 56 soil samples were seasonaly collected from 14 stations in the areas of Karacahöyük, Bahçecik, OGU I, and OGU II. A total of 110 species belonging to 32 genera were encountered including Absidia, Acremonium, Alternaria, Aspergillus, Beauveria, Botryoderma, Chaetomium, Chrysosporium, Cladosporium, Eupenicillium, Eurotium, Fusarium, Geotrichum, Gliocladium, Gonytrichum, Metarrhizium, Mucor, Myrothecium, Paecilomyces, Penicillium, Phoma, Plectosphaerella, Rhizoctania, Rhizopus, Scopulariopsis, Septonema, Stachybotrys, Trichocladium, Trichoderma, Ulocladium, Verticillium, and Wardomyces. Twenty five species were more frequent (all locations) while twenty seven species were rare (only one sample). Mainly, Acremonium kiliense, Aspergillus ochraceus, A. terricola var. americanus, A. versicolor, Cladosporium cladosporioides, Fusarium oxysporum, F. solani, Gliocladium roseum, Penicillium chrysogenum, P. corylophum, P. expansum, P. griseofulvum, P. implicatum, P. restrictum, and Stachybotrys chartarum were the most common and abundant microfungi in all locations. Five species Aspergillus subsessilis, A. terreus var. africanus, Eupenicillium egyptiacum, Paecilomyces ramosus, and Penicillium novae‐zeelandiae are likely to be newly recorded for Turkey. The microfungi number in Eskişehir soils was between 25 000‐234 000 CFU/g (mean value at 126 375 CFU/g). (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A new bitter diterpenoid from Sarcodon scabrosus
Authors: Ma Bing‐Ji , Liu Ji‐Kai
Published: July 2005

The new cyathane‐type diterpenoid sarcodonin I was isolated from the fruiting bodies of the basidiomycete Sarcodon scabrosus. Its structure was determined on the basis of spectroscopic means, including 2D‐NMR (HMBC, HMQC, ROESY, 1H, 1H‐COSY). (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)