bluuebunny/crossref_metadata_2025_split huggingface dataset:
Visual modelling: from images to images
Authors: Pollefeys Marc , Van Gool Luc 
Published: October 2002

AbstractThis paper contains two parts. In the first part an automatic processing pipeline is presented that analyses an image sequence and automatically extracts camera motion, calibration and scene geometry. The system combines state‐of‐the‐art algorithms developed in computer vision, computer graphics and photogrammetry. The approach consists of two stages. Salient features are extracted and tracked throughout the sequence to compute the camera motion and calibration and the 3D structure of the observed features. Then a dense estimate of the surface geometry of the observed scene is computed using stereo matching. The second part of the paper discusses how this information can be used for visualization. Traditionally, a textured 3D model is constructed from the computed information and used to render new images. Alternatively, it is also possible to avoid the need for an explicit 3D model and to obtain new views directly by combining the appropriate pixels from recorded views. It is interesting to note that even when there is an ambiguity on the reconstructed geometry, correct new images can often still be generated. Copyright © 2002 John Wiley & Sons, Ltd.
Single‐view modelling of free‐form scenes
Authors: Zhang Li , Dugas‐Phocion Guillaume , Samson Jean‐Sebastien , Seitz Steven M. 
Published: October 2002

AbstractThis paper presents a novel approach for reconstructing free‐form, texture‐mapped, 3D scene models from a single painting or photograph. Given a sparse set of user‐specified constraints on the local shape of the scene, a smooth 3D surface that satisfies the constraints is generated. This problem is formulated as a constrained variational optimization problem. In contrast to previous work in single‐view reconstruction, our technique enables high‐quality reconstructions of free‐form curved surfaces with arbitrary reflectance properties. A key feature of the approach is a novel hierarchical transformation technique for accelerating convergence on a non‐uniform, piecewise continuous grid. The technique is interactive and updates the model in real time as constraints are added, allowing fast reconstruction of photorealistic scene models. The approach is shown to yield high‐quality results on a large variety of images. Copyright © 2002 John Wiley & Sons, Ltd.
Mechanical stretching force promotes collagen synthesis by cultured cells from human ligamentum flavum via transforming growth factor‐β1
Authors: Nakatani Tetsuya , Marui Takashi , Hitora Toshiaki , Doita Minoru , Nishida Kotaro , Kurosaka Masahiro 
Published: October 2002

AbstractAlthough mechanical stress as a result of spinal instability is known to cause hypertrophy of the ligamentum flavum resulting in degenerative spinal canal stenosis, the mechanism of the ligament hypertrophy is not well understood. In the present study, we investigated the effect of mechanical stretching force on collagen synthesis and transforming growth factor‐β1 (TGF‐β1) production using ligament cells isolated from human ligamentum flavum in vitro. Ligamentum flavum cells (LFCs) were isolated from human ligamentum flavum obtained from patients who underwent lumbar spine surgery. The LFCs were subjected to a mechanical stretching force using a commercially available stretching device that physically deformed the cells. Collagen synthesis and TGF‐β1 production levels in the LFCs were then examined. Notable increases were observed in the gene expressions of collagen types I, III, and V in LFCs subjected to mechanical stretching force. The increase in collagen gene expression of LFCs was inhibited in the presence of anti‐TGF‐β1 antibodies. Production of TGF‐β1 by the LFCs also increased significantly by the mechanical stretching force. Exogenous application of TGF‐β1 was confirmed to increase collagen synthesis of the LFCs. This data indicated that mechanical stretching force can promote TGF‐β1 production by LFCs, resulting in hypertrophy of the ligament.© 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Development of the attachment zones in the rat anterior cruciate ligament: changes in the distributions of proliferating cells and fibrillar collagens during postnatal growth
Authors: Nawata Koji , Minamizaki Takeshi , Yamashita Yasutugu , Teshima Ryota 
Published: October 2002

AbstractThe development of the attachment zones of the anterior cruciate ligament (ACL) is an important consideration when examining the structural properties. The aim of this study was to elucidate the morphological changes and the distribution of proliferating cells and collagen types I, II and III at the attachment zones of the rat ACL during postnatal growth.The majority of proliferating cell nuclear antigen (PCNA) immunostained cells were noted near the ligament insertion, especially at the tibial site, and these cells gradually changed to fibrochondrocyte‐like cells but still produced collagen types I and III at birth until one month old when rapid longitudinal growth of the ACL took place. After one month when the rate of the ligament growth decreased to one thirtieth of that during the first month and the epiphyseal cartilage at the attachment zone had been replaced by bone, these fibrochondrocyte‐like cells began to produce collagen type II and reveal safranin O staining. The immunolabelling pattern to collagen type III was similar to that of PCNA immunostaining during the growth phase.Our findings show that the fibrochondrocytes at the attachment zone may develop from the ligament cells and act as a growth zone for the ligament during the period of ligament growth, and that subsequently, these cells begin to synthesis collagen type II and proteoglycans after epiphyseal ossification. These observations mainly occurred at the tibial attachment zone.© 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Parathyroid hormone‐related peptide and Indian hedgehog expression patterns in naturally acquired equine osteochondrosis
Authors: Semevolos Stacy A. , Brower‐Toland Brent D. , Bent Stephen J. , Nixon Alan J. 
Published: October 2002

AbstractEarly changes in parathyroid hormone‐related peptide (PTH‐rP) and Indian hedgehog (Ihh) expression were examined in equine articular osteochondrosis (OC) as a model of a naturally acquired dyschondroplasia. Cartilage was harvested from OC‐affected femoropatellar or scapulohumeral joints from immature horses and normal control horses of similar age. PTH‐rP expression levels were assessed by semi‐quantitative PCR, in situ hybridization, and immunohistochemistry. Ihh protein expression levels were assessed by immunohistochemistry. Elevated PTH‐rP protein and mRNA expression were identified in the deeper layers of affected articular cartilage and the fibrous tissue of interposing clefts. These changes were confined to the chondrocytes in the OC‐affected cartilage, which had significantly increased PTH‐rP protein and mRNA expression when compared to control cartilages. Ihh protein expression showed similar distribution as PTH‐rP in the deeper layers of articular cartilage; however, only a trend for increased Ihh immunostaining was evident in the OC cartilage when compared to the normal cartilage. Increased PTH‐rP expression in pre‐hypertrophic chondrocytes of diseased OC cartilage suggests a possible link between this peptide and the delayed ossification, which is a consistent histologic alteration in OC. More evidence is necessary to determine the role of Ihh in articular cartilage and if a similar feedback cycle exists as previously described for the growth plate.© 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Cryopreservation of intact human articular cartilage
Authors: Jomha N. M. , Lavoie G. , Muldrew K. , Schachar N. S. , McGann L. E. 
Published: October 2002

AbstractDamaged articular cartilage (AC) impairs joint function and many treatment techniques are being investigated to determine their long term results. Successful cryopreservation of AC can provide a reliable source of intact matrix with viable chondrocytes to maintain the cartilage over long periods of time. This study investigated the application of an established cryopreservation protocol to determine the recovery of intact chondrocytes from human AC. Ten millimeter diameter osteochondral dowels were harvested from two human donors. The cryopreservation protocol was performed and the samples were rapidly warmed from varying experimental holding temperatures (−10, −20, −30, −40°C), with and without plunging into liquid nitrogen, using 1 M dimethyl sulfoxide as cryoprotectant. The cartilage was stained with membrane integrity dyes and viewed under fluorescence microscopy. The percent of intact chondrocytes was compared to fresh controls. Low recovery of intact chondrocytes was recorded from all temperature levels with and without cryoprotectant. The results of this experiment demonstrated that the cryopreservation procedure used to achieve moderate success with intact sheep AC was not successful with intact human AC and further investigation is required.© 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Effects of combined administration of transforming growth factor‐β1 and epidermal growth factor on properties of the in situ frozen anterior cruciate ligament in rabbits
Authors: Sakai Toshihiko , Yasuda Kazunori , Tohyama Harukazu , Azuma Hirotaka , Nagumo Akira , Majima Tokifumi , Frank Cyril B. 
Published: October 2002

AbstractThe mechanical properties of tendon autografts used in reconstruction of the anterior cruciate ligament (ACL) are reduced after surgery. Previous studies showed that growth factors such as transforming growth factor‐β1 (TGF‐β1) and epidermal growth factor (EGF) can stimulate fibroblast proliferation and increase collagen and noncollagenous protein synthesis by these cells. These factors might be useful, therefore, in preventing graft deterioration after transplantation or accelerating mechanical restoration of the deteriorated graft. The purpose of our study, therefore, was to clarify the effects of TGF‐β1 and EGF on biomechanical properties using an in situ freeze‐thaw ACL model in the rabbit. A total of 142 rabbits underwent the freeze‐thaw treatment in the right ACL and were then divided into four groups. Group I served as a freeze‐thaw, but otherwise untreated control. In Group II, a delivery vehicle (fibrin sealant) alone was applied. In Group III, 4‐ng TGF‐β1 and 100‐ng EGF mixed with the vehicle were applied. In Group IV, higher doses (2‐μg TGF‐β1 and 50‐μg EGF) of growth factors were mixed with the vehicle. The groups were compared at 6 and 12 weeks on the basis of mechanical properties, water content, and histological and ultrastructural observations. The cross‐sectional area of Group III (average, 7.1 mm2) was significantly less than that of Groups I, II, and IV (9.0, 8.2, and 9.4 mm2, respectively) at 12 weeks. The tensile strength of Group III (62.2 MPa) was significantly greater than that of Groups I, II, and IV (35.6, 43.7, and 36.9 MPa, respectively) at 12 weeks, while the water content of Group III (70.7%) was significantly lower than that of Group I (75.2%). No other significant differences occurred among Groups I, II, and IV. A unimodal distribution of collagen fibril diameters was noted in Groups I and II, while a bimodal pattern was found in Group III. This study demonstrated that low‐dose application of TGF‐β1 and EGF significantly inhibited not only the increased water content and cross‐sectional area, but also the decreased tensile strength caused by the freeze‐thaw treatment, while a high dose of TGF‐β1 and EGF does not have the same beneficial effects.© 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Prostaglandin E1 analog inhibits the microglia function: suppression of lipopolysaccharide‐induced nitric oxide and TNF‐α release
Authors: Chuai Miao , Ogata Tadanori , Morino Tadao , Okumura Hideo , Yamamoto Haruyasu , Schubert Peter 
Published: October 2002

AbstractRelease of nitric oxide and TNF‐α, a toxic cytokine, have been reported to accelerate neuronal damage under several pathological conditions, such as trauma or ischemia in the central nervous system. In the present study, we tested the effect of alprostadil alfadex, a prostaglandin El analog, on cultured microglia from the rat spinal cord. The cultured microglia were exposed to lipopolysaccharide (LPS) (100 ng/ml), an endotoxin, for 24 h, then the released nitric oxide and TNF‐α in the culture media was analyzed. The released nitric oxide was detected by the Griess reaction and released TNF‐α was measured using ELISA method. The LPS‐induced nitric oxide release was inhibited by the simultaneous addition of alprostadil alfadex in a dose‐dependent manner (0.1–100 μM). The LPS‐induced TNF‐α release was also inhibited by alprostadil alfadex addition (0.1–100 μM). The IC50 values of alprostadil alfadex on nitric oxide and TNF‐α release were about 1 and 10 μM, respectively. These results suggest that prostaglandin El possibly protects spinal cord neurons from several types of neurodegenerative damage, not only via increased blood supply, but also via inhibition of pathological immunoreactions of activated microglia.© 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Defective neurite outgrowth in aphidicolin/cAMP‐induced motor neurons expressing mutant Cu/Zn superoxide dismutase
Authors: Lee Kwang‐Woo , Kim Hyun‐Jeong , Sung Jung‐Joon , Park Kyung‐Seok , Kim Manho 
Published: October 2002

AbstractAmyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder characterized by motor neuron involvement. Mutations in the human Cu/Zn superoxide dismutase (SOD1) gene are found in some cases of familial ALS. Many studies have reported SOD1 mutation‐related neurodegeneration. However, whether or not a mutant SOD1 affects neural development has not been demonstrated. We developed motor neuron‐neuroblastoma hybrid cells that expressed a mutant (G93A) or the wild type (WT) SOD1. Cells were differentiated by dibutyryl cAMP and aphidicolin. The mutant showed a defect in neurite outgrowth and had decreased viability. Cytochrome c released and nuclear fragmentation were observed. Western blot analysis showed that the amount of neurofilament and microtubule associated proteins‐2 (MAP‐2) decreased during differentiation. These results suggest that the defect in neurite outgrowth of mutant SOD1 cells is a cytoskeletal defect and is associated with neuronal death.
Ontogenetic development and neuroanatomical localization of growth hormone‐releasing hormone (GHRH) in the brain and pituitary gland of pejerrey fish Odontesthes bonariensis
Authors: Miranda Leandro Andrés , Strobl‐Mazzulla Pablo Hernán , Somoza Gustavo Manuel 
Published: October 2002

AbstractThe presence and distribution of growth hormone‐releasing hormone (GHRH) were studied by immunocytochemistry in adult and developing pejerrey fish, Odontesthes bonariensis (Atheriniformes). A few perikarya and fibers with immunoreactivity to GHRH (ir‐GHRH) were identified in the olfactory bulbs at hatching. One week later, scattered ir‐GHRH cell bodies were observed in the preoptic area and some fibers were detected entering the pituitary gland. Isolated ir‐GHRH perikarya were revealed in the hypothalamus and in the medulla oblongata (MO) 3 weeks after hatching. Seven weeks after hatching, ir‐GHRH cells were also identified in the nucleus of the lateral lemniscus and the cerebellum. Both nuclei presented strong ir‐GHRH projections extending rostro‐ventrally. At 11 weeks after hatching another group of ir‐GHRH cells were revealed in the midbrain tegmentum. After that time the pattern of distribution of ir‐GHRH structures remained unchanged. At 1 week after hatching and later, the pituitary gland consistently revealed ir‐GHRH cells and fibers mainly in the proximalis pars distalis and in a minor proportion of the pars intermedia since week 1. The pineal gland showed ir‐GHRH cells projecting into the pineal lumen, at week 6 after hatching and later. The pineal stalk and the subcomissural organ also presented ir‐GHRH structures. Additionally, ir‐GHRH material was found from week 3 to the adult stage in the following extraneural organs: gills, gut, kidney and hepatopancreas. These results represent the anatomical substrate for understanding the physiology of GHRH peptide in pejerrey, adding information on the ontogeny of neural structures expressing GHRH.
METASTABILITY IN THE CLASSICAL, TRUNCATED BECKER–DÖRING EQUATIONS
Authors: Duncan Dugald B. , Dunwell Rachel M. 
Published: October 2002

AbstractWe show that in the classical (fixed-monomer-concentration) Becker–Döring equations truncated at finite cluster size, the slow evolution (metastability) of solutions can be explained in terms of the eigensystem of this linear ordinary differential equation (ODE) system. In particular, for a common choice of coagulation–fragmentation rate constants there is an extremely small non-zero eigenvalue which is isolated from the rest of the spectrum. We give estimates and bounds on the size of this eigenvalue, the gap between it and the second smallest, and the size of the largest eigenvalue. The bounds on the smallest eigenvalue are very sharp when the system size and/or monomer concentration are large enough.AMS 2000 Mathematics subject classification: Primary 34A30; 15A18; 65F15
MAXIMAL IDEALS IN THE ALGEBRA OF OPERATORS ON CERTAIN BANACH SPACES
Authors: Laustsen Niels Jakob 
Published: October 2002

AbstractFor a Banach space $\mathfrak{X}$, let $\mathcal{B}(\mathfrak{X})$ denote the Banach algebra of all continuous linear operators on $\mathfrak{X}$. First, we study the lattice of closed ideals in $\mathcal{B}(\mathfrak{J}_p)$, where $1 \lt p \t \infty$ and $\mathfrak{J}_p$ is the $p$th James space. Our main result is that the ideal of weakly compact operators is the unique maximal ideal in $\mathcal{B}(\mathfrak{J}_p)$. Applications of this result include the following.(i) The Brown–McCoy radical of $\mathcal{B}(\mathfrak{X})$, which by definition is the intersection of all maximal ideals in $\mathcal{B}(\mathfrak{X})$, cannot be turned into an operator ideal. This implies that there is no ‘Brown–McCoy’ analogue of Pietsch’s construction of the operator ideal of inessential operators from the Jacobson radical of $\mathcal{B}(\mathfrak{X})/\mathcal{A}(\mathfrak{X})$.(ii) For each natural number $n$ and each $n$-tuple $(m_1,\dots,m_n)$ in $\{k^2\mid k\in\mathbb{N}\}\cup\{\infty\}$, there is a Banach space $\mathfrak{X}$ such that $\mathcal{B}(\mathfrak{X})$ has exactly $n$ maximal ideals, and these maximal ideals have codimensions $m_1,\dots,m_n$ in $\mathcal{B}(\mathfrak{X})$, respectively; the Banach space $\mathfrak{X}$ is a finite direct sum of James spaces and $\ell_p$-spaces.Second, building on the work of Gowers and Maurey, we obtain further examples of Banach spaces $\mathfrak{X}$ such that all the maximal ideals in $\mathcal{B}(\mathfrak{X})$ can be classified. We show that the ideal of strictly singular operators is the unique maximal ideal in $\mathcal{B}(\mathfrak{X})$ for each hereditarily indecomposable Banach space $\mathfrak{X}$, and we prove that there are $2^{2^{\aleph_0}}$ distinct maximal ideals in $\mathcal{B}(\mathfrak{G})$, where $\mathfrak{G}$ is the Banach space constructed by Gowers to solve Banach’s hyperplane problem.AMS 2000 Mathematics subject classification: Primary 47D30; 47D50; 46H10; 16D30
A DIMENSION-DEPENDENT MAXIMAL INEQUALITY
Authors: Shvidkoy Roman 
Published: October 2002

AbstractIn this short note we show that $\sup\{\|M_\nu\|:\nu\text{ is a measure on }\mathbb{R}^n\}$, where $\|M_\nu\|$ denotes the centred Hardy–Littlewood maximal operator, depends exponentially on $n$.AMS 2000 Mathematics subject classification: Primary 42B25
ON THE FREIHEITSSATZ IN CERTAIN ONE-RELATOR FREE PRODUCTS. III
Authors: Shwartz Robert 
Published: October 2002

AbstractWe study one-relator free products in which the relator has free-product length $4$. We find conditions for such presentations to have a Freiheitssatz and classify all non-aspherical presentations under certain conditions.AMS 2000 Mathematics subject classification: Primary 20F05; 20F06; 20F10
BANACH ALGEBRAS WEAK* GENERATED BY THEIR IDEMPOTENTS
Authors: Pedersen Thomas Vils 
Published: October 2002

AbstractFor a closed set $E$ contained in the closed unit interval, we show that the big Lipschitz algebra $\varLambda_{\gamma}(E)$ $(0\lt\gamma\lt1)$ is sequentially weak$^{\ast}$ generated by its idempotents if and only if it is weak$^{\ast}$ generated by its idempotents if and only if the little Lipschitz algebra $\lambda_{\gamma}(E)$ is generated by its idempotents, and we describe a class of perfect symmetric sets for which this holds. Moreover, we prove that $\varLambda_1(E)$ is sequentially weak$^{\ast}$ generated by its idempotents if and only if $E$ is of measure zero. Finally, we show that the quotient algebras$$ \mathcal{A}_{\beta}/\overline{J_{\beta}(E)}^{\text{weak}^{\ast}} $$of the Beurling algebras need not be weak$^{\ast}$ generated by their idempotents, when $E$ is of measure zero and $\beta\ge\tfrac{1}{2}$.AMS 2000 Mathematics subject classification: Primary 46J10; 46J30; 26A16; 42A16
Turbulent diffusion in the geostrophic
inverse cascade
Authors: SMITH K. S. , BOCCALETTI G. , HENNING C. C. , MARINOV I. , TAM C. Y. , HELD I. M. , VALLIS G. K. 
Published: October 2002

Motivated in part by the problem of large-scale lateral turbulent heat transport in the
Earth's atmosphere and oceans, and in part by the problem of turbulent transport
itself, we seek to better understand the transport of a passive tracer advected by
various types of fully developed two-dimensional turbulence. The types of turbulence
considered correspond to various relationships between the streamfunction and the
advected field. Each type of turbulence considered possesses two quadratic invariants
and each can develop an inverse cascade. These cascades can be modified or halted, for
example, by friction, a background vorticity gradient or a mean temperature gradient.
We focus on three physically realizable cases: classical two-dimensional turbulence,
surface quasi-geostrophic turbulence, and shallow-water quasi-geostrophic turbulence
at scales large compared to the radius of deformation. In each model we assume that
tracer variance is maintained by a large-scale mean tracer gradient while turbulent
energy is produced at small scales via random forcing, and dissipated by linear
drag. We predict the spectral shapes, eddy scales and equilibrated energies resulting
from the inverse cascades, and use the expected velocity and length scales to predict
integrated tracer fluxes.When linear drag halts the cascade, the resulting diffusivities are decreasing functions of the drag coefficient, but with different dependences for each case. When β is
significant, we find a clear distinction between the tracer mixing scale, which depends
on β but is nearly independent of drag, and the energy-containing (or jet) scale, set
by a combination of the drag coefficient and β. Our predictions are tested via high-
resolution spectral simulations. We find in all cases that the passive scalar is diffused
down-gradient with a diffusion coefficient that is well-predicted from estimates of
mixing length and velocity scale obtained from turbulence phenomenology.