bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling the effect of copper availability on bacterial denitrification
Authors: Woolfenden Hugh C. , Gates Andrew J. , Bocking Chris , Blyth Mark G. , Richardson David J. , Moulton Vincent 
Published: July 2013

AbstractWhen denitrifying bacteria such as Paracoccus denitrificans respire anaerobically they convert nitrate to dinitrogen gas via a pathway which includes the potent greenhouse gas, nitrous oxide (N2O). The copper‐dependent enzyme Nitrous Oxide reductase (Nos) catalyzes the reduction of N2O to dinitrogen. In low‐copper conditions, recent experiments in chemostats have demonstrated that Nos efficiency decreases resulting in significant N2O emissions. For the first time, a chemostat‐based mathematical model is developed that describes the anaerobic denitrification pathway based on Michaelis–Menten kinetics and published kinetic parameters. The model predicts steady‐state enzyme levels from experimental data. For low copper concentrations, the predicted Nos level is significantly reduced, whereas the levels for the non copper‐dependent reductases in the pathway remain relatively unaffected. The model provides time courses for the pathway metabolites that accurately reflect previously published experimental data. In the absence of experimental data purely predictive analyses can also be readily performed by calculating the relative Nos level directly from the copper concentration. Here, the model quantitatively estimates the increasing level of emitted N2O as the copper level decreases.
Medical treatment of dystonia
Authors: Jankovic Joseph 
Published: July 2013

ABSTRACTMedications such as anticholinergic drugs, dopamine modulators, baclofen, muscle relaxants, and other pharmacologic agents have been used for a long time to treat dystonia, but the introduction of botulinum toxin and deep brain stimulation clearly revolutionized the symptomatic treatment of this neurological movement disorder. Therapy of dystonia can be divided into the following categories: (1) physical, supportive, and ancillary therapy; (2) pharmacologic treatment; (3) chemodenervation with botulinum toxin; and (4) peripheral and central surgery (deep brain stimulation). Except in some cases of secondary dystonia, pathogenesis‐targeted or disease‐modifying therapy is currently not available. This review focuses on evidence‐based medical treatment of dystonia, highlighting recent advances, with emphasis on individualized approach. © 2013 Movement Disorder Society
The focal dystonias: Current views and challenges for future research
Authors: Jinnah H. A. , Berardelli Alfredo , Comella Cynthia , DeFazio Giovanni , DeLong Mahlon R. , Factor Stewart , Galpern Wendy R. , Hallett Mark , Ludlow Christy L. , Perlmutter Joel S. , Rosen Ami R. ,   for the Dystonia Coalition Investigators
Published: July 2013

ABSTRACTThe most common forms of dystonia are those that develop in adults and affect a relatively isolated region of the body. Although these adult‐onset focal dystonias are most prevalent, knowledge of their etiologies and pathogenesis has lagged behind some of the rarer generalized dystonias, in which the identification of genetic defects has facilitated both basic and clinical research. This summary provides a brief review of the clinical manifestations of the adult‐onset focal dystonias, focusing attention on less well understood clinical manifestations that need further study. It also provides a simple conceptual model for the similarities and differences among the different adult‐onset focal dystonias as a rationale for lumping them together as a class of disorders while at the same time splitting them into subtypes. The concluding section outlines some of the most important research questions for the future. Answers to these questions are critical for advancing our understanding of this group of disorders and for developing novel therapeutics. © 2013 Movement Disorder Society
Polarized light microscopy in reproductive and developmental biology
Authors: Koike‐Tani Maki , Tani Tomomi , Mehta Shalin B. , Verma Amitabh , Oldenbourg Rudolf 
Published: July 2013

SUMMARYThe polarized light microscope reveals orientational order in native molecular structures inside living cells, tissues, and whole organisms. It is a powerful tool used to monitor and analyze the early developmental stages of organisms that lend themselves to microscopic observations. In this article, we briefly discuss the components specific to a traditional polarizing microscope and some historically important observations on: chromosome packing in the sperm head, the first zygote division of the sea urchin, and differentiation initiated by the first asymmetric cell division in the sand dollar. We then introduce the LC‐PolScope and describe its use for measuring birefringence and polarized fluorescence in living cells and tissues. Applications range from the enucleation of mouse oocytes to analyzing the polarized fluorescence of the water strider acrosome. We end with new results on the birefringence of the developing chick brain, which we analyzed between developmental stages of days 12–20. Mol. Reprod. Dev. 82: 548–562, 2015. © 2013 Wiley Periodicals, Inc.
Measuring Shear‐Induced Adhesion of Gecko‐Inspired Fibrillar Arrays Using Scanning Probe Techniques
Authors: Li Yasong , Zhang Cheng , Zhou James H.‐W. , Menon Carlo , Gates Byron D. 
Published: July 2013

AbstractThe natural ability of geckos and spiders to climb almost all surfaces using the compliant, nano‐structured components on their feet provides motivation for making bio‐inspired adhesives. The goal of the studies in this paper is to create an analytical technique for improving the ability to characterize dry adhesives modeled after these biological systems. The technique described herein uses a scanning probe microscope to manipulate a flat test surface in contact with biomimetic fibrillar arrays while monitoring the adhesion forces. Adhesion forces were measured after both normal contact and shear‐induced contact between the nano‐structured fibrils and the test surface. Results confirm that the adhesion forces are higher for bio‐inspired adhesives after a shear‐induced contact. Variations in these forces can be measured across the sample with micrometer‐scale lateral resolution. This method of analysis can be extended to evaluate bio‐inspired dry adhesives with realistic mechanisms of attachment utilized in robotic and similar applications of these materials.
Thermally induced phase separation of poly(vinylidene fluoride)/diluent systems: Optical microscope and infrared spectroscopy studies
Authors: Yang Hao‐Cheng , Wu Qing‐Yun , Liang Hong‐Qin , Wan Ling‐Shu , Xu Zhi‐Kang 
Published: July 2013

ABSTRACTThermally induced phase separation (TIPS) has been developed to prepare porous membranes. The porous structures are mainly dependent on diluents adopted in the TIPS process. We obtained two typical morphologies of poly(vinylidene fluoride) (PVDF) membranes using cyclohexanone (CO) and propylene carbonate (PC) as diluents, respectively. SEM observation displays that porous spherulites are formed from PVDF/CO system, whereas smooth particles result from PVDF/PC system. The TIPS processes of these two systems have been investigated in detail by optical microscope observation and temperature‐dependent FTIR combined with two‐dimensional infrared correlation analysis. Rapid crystallization of PVDF can be seen around 110 °C in the PVDF/CO system, which is consistent with the results of temperature‐dependent FTIR spectra. The spectral evolution indicates a transform of PVDF from amorphous to α‐phase after 110 °C. The νs(CO) band at 1712 cm−1 narrows and the νs(CF) band at 1188 cm−1 shifts to 1192 cm−1 before crystallization, which implies the destruction of interaction between PVDF and CO. In contrast, the PVDF/PC system shows slow crystallization with all‐trans conformation assigned to β‐phase and γ‐phase below 60 °C but no obvious change of polymer−diluent interaction. We propose two mechanisms for the different phase behaviors of PVDF/CO and PVDF/PC systems: a solid−liquid phase separation after destruction of polymer−diluent interaction in the former, and a liquid−liquid phase separation process coupled with rich‐phase crystallization in the later. This work may provide new insight into the relationship among morphologies, crystal forms, and phase separation processes, which will be helpful to adjust membrane structure. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1438–1447
An estimate of some analysis‐error statistics using the Global Modeling and Assimilation Office observing‐system simulation framework
Authors: Errico Ronald M. , Privé Nikki C. 
Published: July 2013

AbstractThe observing‐system simulation experiment (OSSE) framework developed at the National Aeronautics and Space Administration (NASA), Global Modeling and Assimilation Office (GMAO) is used to estimate some characteristics of analysis error. This is possible because, within the framework, the true state of the simulated atmosphere is known and, after suitable interpolation to a common grid, can be simply differenced with the analysis to compute errors explicitly. The only assumption is that the OSSE is sufficiently realistic so that error statistics derived from it adequately describe those obtained when analyzing observations of the real atmosphere. Attention here is restricted to the troposphere during the months of July and August at 0000 and 1200 UTC using an observation data set from 2011.Analysis‐error statistics presented here include geographical distributions of temporal variances, power spectra of spherical harmonics and correlations in meridional, latitudinal and vertical directions. Our most noteworthy results include the revelation through spectral analysis that only synoptic scales are well analyzed and that horizontal correlation lengths in the extratropics are short, with little vertical variation, and the dominance of rotational wind errors in contrast to divergent ones.Also examined are fractional reductions in background‐error variances due to analysis of observations. These reveal that in most geographical regions throughout the troposphere, errors are reduced by analyzing observations, as intended. The reductions are typically small, however (−10% in most regions), as should be expected from consideration of the equilibration of errors implied by the Kalman‐filter equations.
Evaluation of seismic behavior improvement in RC MRFs retrofitted by controlled rocking wall systems
Authors: Zibaei H. , Mokari J. 
Published: July 2013

SUMMARYUsing rocking wall systems is a recent technique to improve seismic behavior in reinforced concrete structures. This paper compares three 10‐story and three 20‐story reinforced concrete frames (moment‐resisting frames) with intermediate ductility, reinforced concrete frames with shear wall, and reinforced concrete frames with controlled rocking wall (RCRW) by the use of pushover analysis. At the end of the research, the wall in a 20‐story RCRW system is post‐tensioned then analyzed, and its results were compared with RCRW results. Simulation and numerical analysis were performed with OpenSees software. The results show that plastic hinge formation and inter‐story drifts are well distributed in the structure with rocking wall system in comparison with the other systems. Meanwhile, energy dissipation and displacement ductility are increased in RCRW frames. With post‐tensioning wall in RCRW, the drift ratios are more uniformed. Copyright © 2013 John Wiley & Sons, Ltd.
Chronological Improvement in Survival Following Rectal Cancer Surgery: A Large‐Scale, Single‐Center Study
Authors: Lee Jong Lyul , Yu Chang Sik , Kim Chan Wook , Yoon Yong Sik , Lim Seok‐Byung , Kim Jin Cheon 
Published: July 2013

AbstractBackgroundTotal mesorectal excision (TME) and preoperative chemoradiation therapy (PCRT) for rectal cancer are used sequentially in our center. The aim of this study was to evaluate survival of patients with stage II/III rectal cancer chronologically and to determine whether therapeutic advances associated with TME and PCRT have improved patient survival.MethodsA retrospective review of 2,197 patients from July 1989 to December 2006 was conducted. The time period (P) for this study was divided into three groups: P1 (1989–1995), P2 (1996–2001) for TME, P3 (2002–2006) for PCRT. Cancer‐specific survival (CSS), disease‐free survival (DFS), and recurrences among the three periods were investigated.ResultsA total of 293 patients in P1, 836 patients in P2, and 1,068 patients in P3 were enrolled. The 5‐year CSS in stages II and III was statistically different between P1/P2 and P3 (stage II, p = 0.008; stage III, p < 0.001). The 5‐year DFS was significantly different between P1/P2 and P3 for stage III (p = 0.001). The local recurrence and systemic recurrence rates decreased during P3, but there was no significant difference between the three periods for stage II. For stage III, local recurrence was significantly different between the three periods (P1 vs. P2, p = 0.002; P1 vs. P3, p < 0.001; P2 vs. P3, p = 0.008).ConclusionsWe identified an improvement in survival for stage II/III rectal cancer and a decrease in local recurrence for stage III rectal cancer during P3, the most recent period. This may be due to frequent application of PCRT based on the TME.
Attachment and psychological well‐being among adolescents with and without disabilities in Kenya: The mediating role of identity formation
Authors: Abubakar Amina , Alonso‐Arbiol Itziar , Van de Vijver Fons J.R. , Murugami Margret , Mazrui Lubna , Arasa Josephine 
Published: July 2013

ABSTRACTThe current study is aimed at evaluating the relationship between attachment and identity development, and their influence on psychological well‐being in adolescents with and without disabilities in Kenya. The sample was composed of 296 adolescents (151 with disabilities and 145 without any disability). The mean age in our sample was 16.84 years (SD = 1.75). Adolescents with disabilities had significantly lower scores in identity formation, paternal attachment, and life satisfaction. A path model indicated that identity formation partially mediated the relationship between secure attachment and psychological well‐being. Our findings indicate that both parent and peer attachment play an important role in the identity formation and psychological well‐being of adolescents in Kenya, irrespective of a disabling condition. A multigroup analysis indicated that while the structure of the relationship between variables held for groups, the pattern and strength of the relationships differed. Implications for practice, especially the guidance and counseling services in schools, are discussed.
Experiments on an elliptic circulation control aerofoil
Authors: Wetzel Drew A. , Griffin John , Cattafesta Louis N. 
Published: July 2013

AbstractExperiments are performed on an elliptic circulation control aerofoil in an open-jet wind tunnel facility. The influence of blowing from a single trailing-edge slot on the external flow is assessed using two-component particle image velocimetry (PIV) and steady surface pressure measurements. The test section configuration (open jet or closed wall) significantly affects the leading-edge region of the flow field. PIV is also used to measure the curved wall jet and its interaction with the external flow near the trailing edge. PIV measurements of the curved wall jet reveal mean tangential velocity similarity in the outer region of the flow above the location where the tangential velocity reaches a local maximum. The length and velocity parameters required for similarity scale with the product of the chord Reynolds number and the momentum coefficient in accordance with the recent publication by Stalnov, Kribus & Seifert (J. Renew. Sustain. Energy, vol. 2, 2010, p. 063101). The separation location is also a function of the product of these parameters. The dataset is used to assemble equations to predict the similarity length scales, velocity scales and separation location. These equations compare well with the present measurements.
The unifying theory of scaling in thermal convection: the updated prefactors
Authors: Stevens Richard J. A. M. , van der Poel Erwin P. , Grossmann Siegfried , Lohse Detlef 
Published: July 2013

AbstractThe unifying theory of scaling in thermal convection (Grossmann & Lohse, J. Fluid. Mech., vol. 407, 2000, pp. 27–56; henceforth the GL theory) suggests that there are no pure power laws for the Nusselt and Reynolds numbers as function of the Rayleigh and Prandtl numbers in the experimentally accessible parameter regime. In Grossmann & Lohse (Phys. Rev. Lett., vol. 86, 2001, pp. 3316–3319) the dimensionless parameters of the theory were fitted to 155 experimental data points by Ahlers & Xu (Phys. Rev. Lett., vol. 86, 2001, pp. 3320–3323) in the regime $3\times 1{0}^{7} \leq \mathit{Ra}\leq 3\times 1{0}^{9} $ and $4\leq \mathit{Pr}\leq 34$ and Grossmann & Lohse (Phys. Rev. E, vol. 66, 2002, p. 016305) used the experimental data point from Qiu & Tong (Phys. Rev. E, vol. 64, 2001, p. 036304) and the fact that $\mathit{Nu}(\mathit{Ra}, \mathit{Pr})$ is independent of the parameter $a$, which relates the dimensionless kinetic boundary thickness with the square root of the wind Reynolds number, to fix the Reynolds number dependence. Meanwhile the theory is, on the one hand, well-confirmed through various new experiments and numerical simulations; on the other hand, these new data points provide the basis for an updated fit in a much larger parameter space. Here we pick four well-established (and sufficiently distant) $\mathit{Nu}(\mathit{Ra}, \mathit{Pr})$ data points and show that the resulting $\mathit{Nu}(\mathit{Ra}, \mathit{Pr})$ function is in agreement with almost all established experimental and numerical data up to the ultimate regime of thermal convection, whose onset also follows from the theory. One extra $\mathit{Re}(\mathit{Ra}, \mathit{Pr})$ data point is used to fix $\mathit{Re}(\mathit{Ra}, \mathit{Pr})$. As $\mathit{Re}$ can depend on the definition and the aspect ratio, the transformation properties of the GL equations are discussed in order to show how the GL coefficients can easily be adapted to new Reynolds number data while keeping $\mathit{Nu}(\mathit{Ra}, \mathit{Pr})$ unchanged.
The drag-adjoint field of a circular cylinder wake at Reynolds numbers 20, 100 and 500
Authors: Wang Qiqi , Gao Jun-Hui 
Published: July 2013

AbstractThis paper analyses the adjoint solution of the Navier–Stokes equation. We focus on flow across a circular cylinder at three Reynolds numbers, ${\mathit{Re}}_{D} = 20, 100$ and $500$. The quantity of interest in the adjoint formulation is the drag on the cylinder. We use classical fluid mechanics approaches to analyse the adjoint solution, which is a vector field similar to a flow field. Production and dissipation of kinetic energy of the adjoint field is discussed. We also derive the evolution of circulation of the adjoint field along a closed material contour. These analytical results are used to explain three numerical solutions of the adjoint equations presented in this paper. The adjoint solution at ${\mathit{Re}}_{D} = 20$, a viscous steady state flow, exhibits a downstream suction and an upstream jet, the opposite of the expected behaviour of a flow field. The adjoint solution at ${\mathit{Re}}_{D} = 100$, a periodic two-dimensional unsteady flow, exhibits periodic, bean-shaped circulation in the near-wake region. The adjoint solution at ${\mathit{Re}}_{D} = 500$, a turbulent three-dimensional unsteady flow, has complex dynamics created by the shear layer in the near wake. The magnitude of the adjoint solution increases exponentially at the rate of the first Lyapunov exponent. These numerical results correlate well with the theoretical analysis presented in this paper.
Wake states and frequency selection of a streamwise oscillating cylinder
Authors: Leontini Justin S. , Lo Jacono David , Thompson Mark C. 
Published: July 2013

AbstractThis paper presents the results of an in-depth study of the flow past a streamwise oscillating cylinder, examining the impact of varying the amplitude and frequency of the oscillation, and the Reynolds number of the incoming flow. These findings are presented in a framework that shows that the relationship between the frequency of vortex shedding ${f}_{s} $ and the amplitude of oscillation ${A}^{\ast } $ is governed by two primary factors: the first is a reduction of ${f}_{s} $ proportional to a series in ${A}^{\ast 2} $ over a wide range of driving frequencies and Reynolds numbers; the second is nonlinear synchronization when this adjusted ${f}_{s} $ is in the vicinity of $N= {(1- {f}_{s} / {f}_{d} )}^{- 1} $, where $N$ is an integer. Typically, the influence of higher-order terms is small, and truncation to the first term of the series (${A}^{\ast 2} $) well represents the overall trend of vortex shedding frequency as a function of amplitude. However, discontinuous steps are overlaid on this trend due to the nonlinear synchronization. When ${f}_{s} $ is normalized by the Strouhal frequency ${f}_{St} $ (the frequency of vortex shedding from an unperturbed cylinder), the rate at which ${f}_{s} / {f}_{St} $ decreases with amplitude, at least for ${f}_{d} / {f}_{St} = 1$, shows a linear dependence on the Reynolds number. For a fixed $\mathit{Re}= 175$, the truncated series shows that the rate of decrease of ${f}_{s} / {f}_{St} $ with amplitude varies as ${(2- {f}_{d} / {f}_{St} )}^{- 1/ 2} $ for $1\leqslant {f}_{d} / {f}_{St} \leqslant 2$, but is essentially independent of ${f}_{d} / {f}_{St} $ for ${f}_{d} / {f}_{St} \lt 1$. These trends of the rate of decrease of ${f}_{s} $ with respect to amplitude are also used to predict the amplitudes of oscillation around which synchronization occurs. These predicted amplitudes are shown to fall in regions of the parameter space where synchronized modes occur. Further, for the case of varying ${f}_{d} / {f}_{St} $, a very reasonable prediction of the amplitude of oscillation required for the onset of synchronization to the mode where ${f}_{s} = 0. 5{f}_{d} $ is given. In a similar manner, amplitudes at which ${f}_{s} = 0$ are calculated, predicting where the natural vortex shedding is completely supplanted by the forcing. These amplitudes are found to coincide approximately with those at which the onset of a symmetric vortex shedding mode is observed. This result is interpreted as meaning that the symmetric shedding mode occurs when the dynamics crosses over from being dominated by the vortex shedding to being dominated by the forcing.
Three-dimensional instability of the flow around a rotating circular cylinder
Authors: Pralits Jan O. , Giannetti Flavio , Brandt Luca 
Published: July 2013

AbstractThe two-dimensional stationary flow past a rotating cylinder is investigated for both two- and three-dimensional perturbations. The instability mechanisms are analysed using linear stability analysis and the complete neutral curve is presented. It is shown that the first bifurcation in the case of the rotating cylinder occurs for stationary three-dimensional perturbations, confirming recent experiments. Interestingly, the critical Reynolds number at high rotation rates is lower than that for the stationary circular cylinder. The spatial characteristics of the disturbance and a qualitative comparison with the results obtained for linear flows suggest that the stationary unstable three-dimensional mode could be of hyperbolic nature.