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Sample records for bare bones pattern

  1. Bare Bones Pattern Formation: A Core Regulatory Network in Varying Geometries Reproduces Major Features of Vertebrate Limb Development and Evolution

    PubMed Central

    Zhu, Jianfeng; Zhang, Yong-Tao; Alber, Mark S.; Newman, Stuart A.

    2010-01-01

    Background Major unresolved questions regarding vertebrate limb development concern how the numbers of skeletal elements along the proximodistal (P-D) and anteroposterior (A-P) axes are determined and how the shape of a growing limb affects skeletal element formation. There is currently no generally accepted model for these patterning processes, but recent work on cartilage development (chondrogenesis) indicates that precartilage tissue self-organizes into nodular patterns by cell-molecular circuitry with local auto-activating and lateral inhibitory (LALI) properties. This process is played out in the developing limb in the context of a gradient of fibroblast growth factor (FGF) emanating from the apical ectodermal ridge (AER). Results We have simulated the behavior of the core chondrogenic mechanism of the developing limb in the presence of an FGF gradient using a novel computational environment that permits simulation of LALI systems in domains of varying shape and size. The model predicts the normal proximodistal pattern of skeletogenesis as well as distal truncations resulting from AER removal. Modifications of the model's parameters corresponding to plausible effects of Hox proteins and formins, and of the reshaping of the model limb, bud yielded simulated phenotypes resembling mutational and experimental variants of the limb. Hypothetical developmental scenarios reproduce skeletal morphologies with features of fossil limbs. Conclusions The limb chondrogenic regulatory system operating in the presence of a gradient has an inherent, robust propensity to form limb-like skeletal structures. The bare bones framework can accommodate ancillary gene regulatory networks controlling limb bud shaping and establishment of Hox expression domains. This mechanism accounts for major features of the normal limb pattern and, under variant geometries and different parameter values, those of experimentally manipulated, genetically aberrant and evolutionary early forms, with no

  2. Bare Bones of Bioactive Glass

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Paul Ducheyne, a principal investigator in the microgravity materials science program and head of the University of Pernsylvania's Center for Bioactive Materials and Tissue Engineering, is leading the trio as they use simulated microgravity to determine the optimal characteristics of tiny glass particles for growing bone tissue. The result could make possible a much broader range of synthetic bone-grafting applications. Bioactive glass particles (left) with a microporous surface (right) are widely accepted as a synthetic material for periodontal procedures. Using the particles to grow three-dimensional tissue cultures may one day result in developing an improved, more rugged bone tissue that may be used to correct skeletal disorders and bone defects. The work is sponsored by NASA's Office of Biological and Physical Research.

  3. Bare Bones of Bioactive Glass

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Paul Ducheyne, a principal investigator in the microgravity materials science program and head of the University of Pernsylvania's Center for Bioactive Materials and Tissue Engineering, is leading the trio as they use simulated microgravity to determine the optimal characteristics of tiny glass particles for growing bone tissue. The result could make possible a much broader range of synthetic bone-grafting applications. Even in normal gravity, bioactive glass particles enhance bone growth in laboratory tests with flat tissue cultures. Ducheyne and his team believe that using the bioactive microcarriers in a rotating bioreactor in microgravity will produce improved, three-dimensional tissue cultures. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and University of Pennsylvania Center for Bioactive Materials and Tissue Engineering.

  4. Bare-bones teaching-learning-based optimization.

    PubMed

    Zou, Feng; Wang, Lei; Hei, Xinhong; Chen, Debao; Jiang, Qiaoyong; Li, Hongye

    2014-01-01

    Teaching-learning-based optimization (TLBO) algorithm which simulates the teaching-learning process of the class room is one of the recently proposed swarm intelligent (SI) algorithms. In this paper, a new TLBO variant called bare-bones teaching-learning-based optimization (BBTLBO) is presented to solve the global optimization problems. In this method, each learner of teacher phase employs an interactive learning strategy, which is the hybridization of the learning strategy of teacher phase in the standard TLBO and Gaussian sampling learning based on neighborhood search, and each learner of learner phase employs the learning strategy of learner phase in the standard TLBO or the new neighborhood search strategy. To verify the performance of our approaches, 20 benchmark functions and two real-world problems are utilized. Conducted experiments can been observed that the BBTLBO performs significantly better than, or at least comparable to, TLBO and some existing bare-bones algorithms. The results indicate that the proposed algorithm is competitive to some other optimization algorithms.

  5. Reliability Optimization of Radial Distribution Systems Employing Differential Evolution and Bare Bones Particle Swarm Optimization

    NASA Astrophysics Data System (ADS)

    Kela, K. B.; Arya, L. D.

    2014-09-01

    This paper describes a methodology for determination of optimum failure rate and repair time for each section of a radial distribution system. An objective function in terms of reliability indices and their target values is selected. These indices depend mainly on failure rate and repair time of a section present in a distribution network. A cost is associated with the modification of failure rate and repair time. Hence the objective function is optimized subject to failure rate and repair time of each section of the distribution network considering the total budget allocated to achieve the task. The problem has been solved using differential evolution and bare bones particle swarm optimization. The algorithm has been implemented on a sample radial distribution system.

  6. Relationship Between Oral Perception and Habitual Chewing Side for Bare Bone Graft With Dental Implants After Mandibular Reconstruction.

    PubMed

    Noguchi, Tadahide; Tsuchiya, Yoshiyuki; Sarukawa, Shunji; Yamazaki, Yuko; Hayasaka, Jun-Ichi; Sasaguri, Ken-Ichi; Jinbu, Yoshinori; Mori, Yoshiyuki

    2016-07-01

    The purpose of this study was to investigate the relationship between habitual chewing side and perception of the oral mucosa following reconstruction with dental implants. Five patients comprised 2 males and 3 females, with ameloblastoma in 2 patients, odontogenic myxoma in 2 patients, and oral squamous cell carcinoma in 1 patient. They were treated using mandibular reconstruction with bare bone graft after segmental resection of the mandible. Perception (tactile, warm, and cold) was measured at 8 points (chin, lower lip, gingiva, and lateral edge of the tongue, bilaterally). Habitual chewing side was evaluated using a computerized index, the first chewing cycle, and a question on chewing. Perception on resected sides was improved at all measurement points for tactile and cold sensitive evaluation, although sensitivities on the resected side remained below the normal range. In the relationship between habitual chewing side and implanted prostheses in reconstructed bone, the chewing side was the resected side in 2 of the 5 patients. When those 2 patients underwent prosthesis implantation after removal of denture, the chewing side changed from the nonresected side to the resected side. Implant prostheses on resected side were suggested to contribute to masticatory function. Perception in those patients was incomplete but was improved compared with other patients. When prosthesis implantation is performed on the reconstructed side, the resected side may become the habitual chewing side. Recovery of perception can influence acquisition of the habitual chewing side.

  7. Evolutionary patterns of bone histology and bone compactness in xenarthran mammal long bones.

    PubMed

    Straehl, Fiona R; Scheyer, Torsten M; Forasiepi, Analía M; MacPhee, Ross D; Sánchez-Villagra, Marcelo R

    2013-01-01

    Bone microstructure reflects physiological characteristics and has been shown to contain phylogenetic and ecological signals. Although mammalian long bone histology is receiving increasing attention, systematic examination of the main clades has not yet been performed. Here we describe the long bone microstructure of Xenarthra based on thin sections representing twenty-two species. Additionally, patterns in bone compactness of humeri and femora are investigated. The primary bone tissue of xenarthran long bones is composed of a mixture of woven, parallel-fibered and lamellar bone. The vascular canals have a longitudinal, reticular or radial orientation and are mostly arranged in an irregular manner. Concentric rows of vascular canals and laminar organization of the tissue are only found in anteater bones. The long bones of adult specimens are marked by dense Haversian bone, a feature that has been noted for most groups of mammals. In the long bones of armadillos, secondary osteons have an oblique orientation within the three-dimensional bone tissue, thus resulting in their irregular shape when the bones are sectioned transversely. Secondary remodeling is generally more extensive in large taxa than in small taxa, and this could be caused by increased loading. Lines of arrested growth are assumed to be present in all specimens, but they are restricted to the outermost layer in bones of armadillos and are often masked by secondary remodeling in large taxa. Parameters of bone compactness show a pattern in the femur that separates Cingulata and Pilosa (Folivora and Vermilingua), with cingulates having a lower compactness than pilosans. In addition, cingulates show an allometric relationship between humeral and femoral bone compactness.

  8. Evolutionary Patterns of Bone Histology and Bone Compactness in Xenarthran Mammal Long Bones

    PubMed Central

    Straehl, Fiona R.; Scheyer, Torsten M.; Forasiepi, Analía M.; MacPhee, Ross D.; Sánchez-Villagra, Marcelo R.

    2013-01-01

    Bone microstructure reflects physiological characteristics and has been shown to contain phylogenetic and ecological signals. Although mammalian long bone histology is receiving increasing attention, systematic examination of the main clades has not yet been performed. Here we describe the long bone microstructure of Xenarthra based on thin sections representing twenty-two species. Additionally, patterns in bone compactness of humeri and femora are investigated. The primary bone tissue of xenarthran long bones is composed of a mixture of woven, parallel-fibered and lamellar bone. The vascular canals have a longitudinal, reticular or radial orientation and are mostly arranged in an irregular manner. Concentric rows of vascular canals and laminar organization of the tissue are only found in anteater bones. The long bones of adult specimens are marked by dense Haversian bone, a feature that has been noted for most groups of mammals. In the long bones of armadillos, secondary osteons have an oblique orientation within the three-dimensional bone tissue, thus resulting in their irregular shape when the bones are sectioned transversely. Secondary remodeling is generally more extensive in large taxa than in small taxa, and this could be caused by increased loading. Lines of arrested growth are assumed to be present in all specimens, but they are restricted to the outermost layer in bones of armadillos and are often masked by secondary remodeling in large taxa. Parameters of bone compactness show a pattern in the femur that separates Cingulata and Pilosa (Folivora and Vermilingua), with cingulates having a lower compactness than pilosans. In addition, cingulates show an allometric relationship between humeral and femoral bone compactness. PMID:23874932

  9. The influence of impact direction and axial loading on the bone fracture pattern.

    PubMed

    Cohen, Haim; Kugel, Chen; May, Hila; Medlej, Bahaa; Stein, Dan; Slon, Viviane; Brosh, Tamar; Hershkovitz, Israel

    2017-08-01

    The effect of the direction of the impact and the presence of axial loading on fracture patterns have not yet been established in experimental 3-point bending studies. To reveal the association between the direction of the force and the fracture pattern, with and without axial loading. A Dynatup Model POE 2000 (Instron Co.) low energy pendulum impact machine was utilized to apply impact loading on fresh pig femoral bones (n=50). The bone clamp shaft was adjusted to position the bone for three-point bending with and without additional bone compression. Four different directions of the force were applied: anterior, posterior, lateral, and medial. The impacted aspect can be distinguished from the non-impacted aspects based on the fracture pattern alone (the most fractured one); the impact point can be identified on bare bones (the area from which all oblique lines radiate and/or the presence of a chip fragment). None of our experiments (with and without compression) yielded a "true" butterfly fracture, but instead, oblique radiating lines emerged from the point of impact (also known as "false" butterfly). Impacts on the lateral and anterior aspects of the bones produce more and longer fracture lines than impacts on the contralateral side; bones subjected to an impact with axial loading are significantly more comminuted and fragmented. Under axial loading, the number of fracture lines is independent of the impact direction. Our study presents an experimental model for fracture analysis and shows that the impact direction and the presence of axial loading during impact significantly affect the fracture pattern obtained. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Bone Marrow Nails Created by Percutaneous Osteoplasty for Long Bone Fracture: Comparisons Among Acrylic Cement Alone, Acrylic-Cement-Filled Bare Metallic Stent, and Acrylic-Cement-Filled Covered Metallic Stent

    SciTech Connect

    Nakata, Kouhei; Kawai, Nobuyuki; Sato, Morio Cao, Guang; Sahara, Shinya; Sonomura, Tetsuo; Takasaka, Isao; Minamiguchi, Hiroki; Nakai, Motoki

    2011-06-15

    Purpose: This study was designed to compare the strength among bone marrow nails created to treat long bone fractures using interventional procedures. Methods: Twelve resected intact tibiae of healthy swine were used. A circumferential bone fracture was made in nine tibiae and restored with the following created bone marrow nails: acrylic cement alone (ACA) (n = 3), acrylic-cement-filled bare metallic stent (AC-FBMS) (n = 3), and acrylic-cement-filled covered metallic (AC-FCMS) stent (n = 3). The remaining intact tibiae (n = 3) were used as controls. Results: A bone marrow nail was successfully achieved within 30 min in all swine. The maximum injection volume of acrylic cement for creating ACA, AC-FBMS, and AC-FCMS was 1.7 {+-} 0.3, 3.2 {+-} 0.4, and 2.9 {+-} 0.4 mL, respectively. The thickness of bone marrow nail created in the ACA, AC-FBMS, and AC-FCMS groups was 3.6 {+-} 1.0, 10.3 {+-} 0.26, and 9.6 {+-} 0.32 mm, respectively (AC-FBMS group versus AC-FCMS group, p = 0.038), probably because of leakage of acrylic cement surrounding the interstices. The maximum bending power (kilonewton) and bending strength (newton/mm{sup 2}) in the normal long bone, ACA, AC-FBMS, and AC-FCMS groups were: 1.70 {+-} 0.25 and 79.2 {+-} 16.1; 0.21 {+-} 0.11 and 8.8 {+-} 2.8; 0.46 {+-} 0.06 and 18.2 {+-} 1.6; and 0.18 {+-} 0.04 and 7.8 {+-} 2.7, respectively. Conclusions: Although the maximum bending power and bending strength of AC-FBMS were not satisfactory, it was the most robust of the three marrow nails for restoring fractured long bone.

  11. Comparison of neointimal hyperplasia with drug-eluting stents versus bare metal stents in patients undergoing intracoronary bone-marrow mononuclear cell transplantation following acute myocardial infarction.

    PubMed

    Villa, Adolfo; Arnold, Roman; Sánchez, Pedro L; Gimeno, Federico; Ramos, Benigno; Cantero, Teresa; Fernández, Maria Eugenia; Sanz, Ricardo; Gutiérrez, Oliver; Mota, Pedro; García-Frade, Javier; San Román, José Alberto; Fernández-Avilés, Francisco

    2009-06-15

    The aims of this study were to assess the safety of drug-eluting stent (DES) use and to compare the incidence of in-stent restenosis (ISR) and neointimal hyperplasia formation according to the type of stent implanted (DES vs bare-metal stents [BMS]) in patients who underwent intracoronary bone marrow mononuclear cell transplantation after acute ST elevation myocardial infarction. Fifty-nine patients with successfully revascularized ST elevation myocardial infarction (37 using BMS and 22 using DES) underwent paired angiographic examinations at baseline and 6 to 9 months after the intracoronary injection of 91 million +/- 56 million autologous bone marrow mononuclear cells. A subgroup of 30 patients also underwent serial intravascular ultrasound examinations. Off-line angiographic assessment showed 4 cases of binary ISR, primarily in BMS (3 cases), and no major adverse cardiac events were associated with stent type (mean follow-up period 41 +/- 10 months). At follow-up, angiographic late luminal loss was significantly lower in patients with DES than in those patients with BMS (0.35 +/- 0.66 vs 0.71 +/- 0.38 mm, p = 0.011). Multivariate analysis identified the use of DES (beta = -0.32, 95% confidence interval [CI] -0.57 to -0.26, p = 0.03) and a smaller baseline reference vessel diameter (beta = 0.29, 95% CI 0.04 to 0.54, p = 0.02) as independent predictors of lower late loss. Moreover, intravascular ultrasound showed a significant reduction of in-stent neointimal hyperplasia formation related to DES use compared with BMS use (Delta neointimal hyperplasia volume 5.4 mm(3) [95% CI 2.7 to 28.1] vs 35.9 mm(3) [95% CI 22.0 to 43.6], p = 0.035). In conclusion, these findings suggest that the use of DES is safe and may prevent ISR and neointimal hyperplasia formation in patients who undergo intracoronary bone marrow mononuclear cell transplantation after a successfully revascularized ST elevation myocardial infarction.

  12. Trabecular bone pattern factor--a new parameter for simple quantification of bone microarchitecture.

    PubMed

    Hahn, M; Vogel, M; Pompesius-Kempa, M; Delling, G

    1992-01-01

    The stability of trabecular bone depends not only on the amount of bone tissue, but also on the three-dimensional orientation and connectedness of trabeculae, which is summarized as trabecular microarchitecture. In previous studies we could demonstrate that in three-dimensional bone tissue the relation of trabecular plates to rods is reflected in the ratio of concave to convex surfaces of the bone pattern in two-dimensional bone sections. For the quantification of the connectedness of these bone patterns we developed a new histomorphometric parameter called Trabecular Bone Pattern factor (TBPf). The basic idea is that the connectedness of structures can be described by the relation of convex to concave surfaces. A lot of concave surfaces represent a well connected spongy lattice, whereas a lot of convex surfaces indicate a badly connected trabecular lattice in two-dimensional sections. By means of an automatic image analysis system we measure trabecular bone area (A1) and perimeter (P1). A second measurement of these two parameters (now A2 and P2) is done after a simulated dilatation of trabeculae on the screen. This dilatation results in a characteristic change of bone area and perimeter depending on the relation of convex to concave surfaces. TBPf is defined as a quotient of the difference of the first and the second measurement: TBPf = (P1 - P2)/(A1 - A2). First measurements of TBPf in 192 iliac crest bone biopsies of autopsy cases show that there is not only age-related loss of bone volume, but also a decrease of trabecular connectedness. By means of TBPf we can demonstrate a significant difference in the age-related loss of trabecular connectivity between male and female individuals.

  13. Evaluation of trabecular bone patterns on dental radiographic images: influence of cortical bone

    NASA Astrophysics Data System (ADS)

    Amouriq, Yves; Evenou, Pierre; Arlicot, Aurore; Normand, Nicolas; Layrolle, Pierre; Weiss, Pierre; Guédon, Jean-Pierre

    2010-03-01

    For some authors trabecular bone is highly visible in intraoral radiographs. For other authors, the observed intrabony trabecular pattern is a representation of only the endosteal surface of cortical bone, not of intermedullary striae. The purpose of this preliminary study was to investigate the true anatomical structures that are visible in routine dental radiographs and classically denoted trabecular bone. This is a major point for bone texture analysis on radiographs. Computed radiography (CR) images of dog mandible section in molar region were compared with simulations calculated from high-resolution micro-CT volumes. Calculated simulations were obtained using the Mojette Transform. By digitally editing the CT volume, the simulations were separated into trabecular and cortical components into a region of interest. Different images were compared and correlated, some bone micro-architecture parameters calculated. A high correlation was found between computed radiographs and calculated simulations from micro-CT. The Mojette transform was successful to obtain high quality images. Cortical bone did not contribute to change in a major way simulated images. These first results imply that intrabony trabecular pattern observed on radiographs can not only be a representation of the cortical bone endosteal surface and that trabecular bone is highly visible in intraoral radiographs.

  14. Occurrence and pattern of long bone fractures in growing dogs with normal and osteopenic bones.

    PubMed

    Kumar, K; Mogha, I V; Aithal, H P; Kinjavdekar, P; Singh, G R; Pawde, A M; Kushwaha, R B

    2007-11-01

    A retrospective study was undertaken to record the occurrence and pattern of long bone fractures, and the efficacy of Intramedullary (IM) Steinmann pin fixing in growing dogs. All the records of growing dogs during a 10-year-period were screened to record the cause of trauma, the age and sex of the animal, the bone involved, the type and location of the fracture, the status of fixation, alignment, maintenance of fixation and fracture healing. The results were analysed and comparisons were made between growing dogs with normal and osteopenic bones. Among the 310 cases of fractures recorded, the bones were osteopenic in 91 cases (29%). Minor trauma was the principal cause of fracture in dogs with osteopenia (25%), and indigenous breeds were most commonly affected (38%). Fractures in dogs with osteopenic bones were most commonly recorded in the age group of 2-4 months (53%), whereas fractures in normal dogs were almost equally distributed between 2 and 8 months of age. Male dogs were affected significantly more often in both groups. In osteopenic bones, most fractures were recorded in the femur (56%), and they were distributed equally along the length of the bone. Whereas in normal bones, fractures were almost equally distributed in radius/ulna, femur and tibia, and were more often recorded at the middle and distal third of long bones. Oblique fractures were most common in both groups; however, comminuted fractures were more frequent in normal bones, whereas incomplete fractures were more common in osteopenic bones. Ninety-nine fracture cases treated with IM pinning (66 normal, 33 osteopenic) were evaluated for the status of fracture reduction and healing. In a majority of the cases (61%) with osteopenic bones, the diameter of the pin was relatively smaller than the diameter of the medullary cavity (<70-75%), whereas in 68% of the cases in normal bones the pin diameter was optimum. The status of fracture fixing was satisfactory to good in significantly more

  15. Patterned silk film scaffolds for aligned lamellar bone tissue engineering

    PubMed Central

    Tien, Lee W.; Gil, Eun Seok; Park, Sang-Hyug; Mandal, Biman B.; Kaplan, David L.

    2013-01-01

    Various porous biomaterial scaffolds have been utilized for bone tissue engineering; however, they are often limited in their ability to replicate the structural hierarchy and mechanics of native cortical bone. In this study, the alignment and osteogenic differentiation of human mesenchymal stem cells (MSCs) on patterned silk films (PF) was investigated as a bottom-up, biomimetic approach toward engineering cortical bone lamellae. Screening films cast with nine different micro and nano scale groove patterns showed that cellular alignment was mediated by an interplay between the width and depth of the patterns. MSCs were differentiated in osteogenic medium for four weeks on the PF that induced the highest degree of alignment, while flat films (FF) served as controls. Gene expression analysis and calcium quantification indicated that the PF supported osteogenic differentiation while also inducing robust lamellar alignment of cells and matrix deposition. A secondary alignment effect was noted on the PF where a new layer of aligned cells grew over the first layer, but rotated obliquely to the underlying pattern direction and first layer orientation. This layering and rotation of the aligned MSCs resembled the characteristic structural organization observed in native lamellar bone. The ability to control multilayered lamellar structural hierarchy from the interplay between a patterned 2D surface and cells suggests intriguing options for future biomaterial scaffolds designed to mimic native tissue structures. PMID:23070941

  16. Long bone histology of the subterranean rodent Bathyergus suillus (Bathyergidae): ontogenetic pattern of cortical bone thickening.

    PubMed

    Montoya-Sanhueza, Germán; Chinsamy, Anusuya

    2017-02-01

    Patterns of bone development in mammals are best known from terrestrial and cursorial groups, but there is a considerable gap in our understanding of how specializations for life underground affect bone growth and development. Likewise, studies of bone microstructure in wild populations are still scarce, and they often include few individuals and tend to be focused on adults. For these reasons, the processes generating bone microstructural variation at intra- and interspecific levels are not fully understood. This study comprehensively examines the bone microstructure of an extant population of Cape dune molerats, Bathyergus suillus (Bathyergidae), the largest subterranean mammal endemic to the Western Cape of South Africa. The aim of this study is to investigate the postnatal bone growth of B. suillus using undecalcified histological sections (n = 197) of the femur, humerus, tibia-fibula, ulna and radius, including males and females belonging to different ontogenetic and reproductive stages (n = 42). Qualitative histological features demonstrate a wide histodiversity with thickening of the cortex mainly resulting from endosteal and periosteal bone depositions, whilst there is scarce endosteal resorption and remodeling throughout ontogeny. This imbalanced bone modeling allows the tissues deposited during ontogeny to remain relatively intact, thus preserving an excellent record of growth. The distribution of the different bone tissues observed in the cortex depends on ontogenetic status, anatomical features (e.g. muscle attachment structures) and location on the bone (e.g. anterior or lateral). The type of bone microstructure and modeling is discussed in relation to digging behavior, reproduction and physiology of this species. This study is the first histological assessment describing the process of cortical thickening in long bones of a fossorial mammal.

  17. Non-linear pattern formation in bone growth and architecture.

    PubMed

    Salmon, Phil

    2014-01-01

    The three-dimensional morphology of bone arises through adaptation to its required engineering performance. Genetically and adaptively bone travels along a complex spatiotemporal trajectory to acquire optimal architecture. On a cellular, micro-anatomical scale, what mechanisms coordinate the activity of osteoblasts and osteoclasts to produce complex and efficient bone architectures? One mechanism is examined here - chaotic non-linear pattern formation (NPF) - which underlies in a unifying way natural structures as disparate as trabecular bone, swarms of birds flying, island formation, fluid turbulence, and others. At the heart of NPF is the fact that simple rules operating between interacting elements, and Turing-like interaction between global and local signals, lead to complex and structured patterns. The study of "group intelligence" exhibited by swarming birds or shoaling fish has led to an embodiment of NPF called "particle swarm optimization" (PSO). This theoretical model could be applicable to the behavior of osteoblasts, osteoclasts, and osteocytes, seeing them operating "socially" in response simultaneously to both global and local signals (endocrine, cytokine, mechanical), resulting in their clustered activity at formation and resorption sites. This represents problem-solving by social intelligence, and could potentially add further realism to in silico computer simulation of bone modeling. What insights has NPF provided to bone biology? One example concerns the genetic disorder juvenile Pagets disease or idiopathic hyperphosphatasia, where the anomalous parallel trabecular architecture characteristic of this pathology is consistent with an NPF paradigm by analogy with known experimental NPF systems. Here, coupling or "feedback" between osteoblasts and osteoclasts is the critical element. This NPF paradigm implies a profound link between bone regulation and its architecture: in bone the architecture is the regulation. The former is the emergent

  18. Non-Linear Pattern Formation in Bone Growth and Architecture

    PubMed Central

    Salmon, Phil

    2014-01-01

    The three-dimensional morphology of bone arises through adaptation to its required engineering performance. Genetically and adaptively bone travels along a complex spatiotemporal trajectory to acquire optimal architecture. On a cellular, micro-anatomical scale, what mechanisms coordinate the activity of osteoblasts and osteoclasts to produce complex and efficient bone architectures? One mechanism is examined here – chaotic non-linear pattern formation (NPF) – which underlies in a unifying way natural structures as disparate as trabecular bone, swarms of birds flying, island formation, fluid turbulence, and others. At the heart of NPF is the fact that simple rules operating between interacting elements, and Turing-like interaction between global and local signals, lead to complex and structured patterns. The study of “group intelligence” exhibited by swarming birds or shoaling fish has led to an embodiment of NPF called “particle swarm optimization” (PSO). This theoretical model could be applicable to the behavior of osteoblasts, osteoclasts, and osteocytes, seeing them operating “socially” in response simultaneously to both global and local signals (endocrine, cytokine, mechanical), resulting in their clustered activity at formation and resorption sites. This represents problem-solving by social intelligence, and could potentially add further realism to in silico computer simulation of bone modeling. What insights has NPF provided to bone biology? One example concerns the genetic disorder juvenile Pagets disease or idiopathic hyperphosphatasia, where the anomalous parallel trabecular architecture characteristic of this pathology is consistent with an NPF paradigm by analogy with known experimental NPF systems. Here, coupling or “feedback” between osteoblasts and osteoclasts is the critical element. This NPF paradigm implies a profound link between bone regulation and its architecture: in bone the architecture is the regulation. The former is the

  19. Multiscale patterned transplantable stem cell patches for bone tissue regeneration.

    PubMed

    Kim, Jangho; Bae, Won-Gyu; Choung, Han-Wool; Lim, Ki Taek; Seonwoo, Hoon; Jeong, Hoon Eui; Suh, Khap-Yang; Jeon, Noo Li; Choung, Pill-Hoon; Chung, Jong Hoon

    2014-11-01

    Stem cell-based therapy has been proposed as an enabling alternative not only for the treatment of diseases but also for the regeneration of tissues beyond complex surgical treatments or tissue transplantation. In this study, we approached a conceptual platform that can integrate stem cells into a multiscale patterned substrate for bone regeneration. Inspired by human bone tissue, we developed hierarchically micro- and nanopatterned transplantable patches as synthetic extracellular matrices by employing capillary force lithography in combination with a surface micro-wrinkling method using a poly(lactic-co-glycolic acid) (PLGA) polymer. The multiscale patterned PLGA patches were highly flexible and showed higher tissue adhesion to the underlying tissue than did the single nanopatterned patches. In response to the anisotropically multiscale patterned topography, the adhesion and differentiation of human mesenchymal stem cells (hMSCs) were sensitively controlled. Furthermore, the stem cell patch composed of hMSCs and transplantable PLGA substrate promoted bone regeneration in vivo when both the micro- and nanotopography of the substrate surfaces were synergistically combined. Thus, our study concludes that multiscale patterned transplantable stem cell patches may have a great potential for bone regeneration as well as for various regenerative medicine approaches.

  20. Maintaining distances with the engineer: patterns of coexistence in plant communities beyond the patch-bare dichotomy.

    PubMed

    Pescador, David S; Chacón-Labella, Julia; de la Cruz, Marcelino; Escudero, Adrian

    2014-10-01

    Two-phase plant communities with an engineer conforming conspicuous patches and affecting the performance and patterns of coexisting species are the norm under stressful conditions. To unveil the mechanisms governing coexistence in these communities at multiple spatial scales, we have developed a new point-raster approach of spatial pattern analysis, which was applied to a Mediterranean high mountain grassland to show how Festuca curvifolia patches affect the local distribution of coexisting species. We recorded 22 111 individuals of 17 plant perennial species. Most coexisting species were negatively associated with F. curvifolia clumps. Nevertheless, bivariate nearest-neighbor analyses revealed that the majority of coexisting species were confined at relatively short distances from F. curvifolia borders (between 0-2 cm and up to 8 cm in some cases). Our study suggests the existence of a fine-scale effect of F. curvifolia for most species promoting coexistence through a mechanism we call 'facilitation in the halo'. Most coexisting species are displaced to an interphase area between patches, where two opposite forces reach equilibrium: attenuated severe conditions by proximity to the F. curvifolia canopy (nutrient-rich islands) and competitive exclusion mitigated by avoiding direct contact with F. curvifolia. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  1. Physiatrists’ Opinions and Practice Patterns for Bone Health after SCI

    PubMed Central

    Ashe, Maureen C.; Eng, Janice J.; Krassioukov, Andrei

    2011-01-01

    Objective To ascertain physiatrists’ opinions and current practice patterns for bone health management after spinal cord injury (SCI). Study Design Self-report survey Participants Physiatrists who work in teaching rehabilitation centers in Canada. Methods A 4-page 17-question survey (available in French and English) was sent to working physiatrists in all major Canadian SCI rehabilitation centers. Results We had an 85% response rate (22 responses). Physiatrists reported that they should be managing bone health issues after SCI in conjunction with family physicians, and most respondents assess and treat for bone health after SCI. However, just over one-third of the physiatrists reported that the current treatment options are not effective for low bone mass; there was more support for pharmacological treatments than there was for rehabilitation modalities. Conclusion Bone health after SCI is an important health concern that is being managed by physiatrists; however, more discussion and research is needed to ascertain the effectiveness of assessment and treatment options for low bone mass. PMID:18711417

  2. Chronic recurrent multifocal osteomyelitis: typical patterns of bone involvement in whole-body bone scintigraphy.

    PubMed

    Acikgoz, Gunsel; Averill, Lauren W

    2014-08-01

    Chronic recurrent multifocal osteomyelitis (CRMO) is an autoinflammatory bone disease of unknown etiology. It affects children and adolescents predominantly and occurs mostly in the female population. It is characterized by the insidious onset of pain and swelling, with a fluctuating clinical course of relapses and remissions. Typically, several bones are affected, either synchronously or metachronously, and bilateral involvement is common. CRMO most commonly affects the metaphysis of long bones, especially the tibia, femur, and clavicle. The spine, pelvis, ribs, sternum, and mandible may also be affected. Although lesions are mostly multiple, patients may present with a single symptomatic focus. Radiographic findings may be negative early in the course of the disease. Bone scintigraphy is useful in determining the presence of abnormality and the extent of disease. The imaging and clinical features of CRMO overlap with those of infectious osteomyelitis, bone malignancy, and inflammatory arthritis. Nonetheless, CRMO can be confidently diagnosed with the recognition of typical imaging patterns in the appropriate clinical setting. This article reviews imaging findings with special emphasis on bone scintigraphy and specific disease sites.

  3. Influence of Fatigue Loading and Bone Turnover on Bone Strength and Pattern of Experimental Fractures of the Tibia in Mice.

    PubMed

    Bonnet, Nicolas; Gerbaix, Maude; Ominsky, Michael; Ammann, Patrick; Kostenuik, Paul J; Ferrari, Serge L

    2016-07-01

    Bone fragility depends on bone mass, structure, and material properties, including damage. The relationship between bone turnover, fatigue damage, and the pattern and location of fractures, however, remains poorly understood. We examined these factors and their integrated effects on fracture strength and patterns in tibia. Adult male mice received RANKL (2 mg/kg/day), OPG-Fc (5 mg/kg 2×/week), or vehicle (Veh) 2 days prior to fatigue loading of one tibia by in vivo axial compression, with treatments continuing up to 28 more days. One day post fatigue, crack density was similarly increased in fatigued tibiae from all treatment groups. After 28 days, the RANKL group exhibited reduced bone mass and increased crack density, resulting in reduced bone strength, while the OPG-Fc group had greater bone mass and bone strength. Injury repair altered the pattern and location of fractures created by ex vivo destructive testing, with fractures occurring more proximally and obliquely relative to non-fatigued tibia. A similar pattern was observed in both non-fatigued and fatigued tibia of RANKL. In contrast, OPG-Fc prevented this fatigue-related shift in fracture pattern by maintaining fractures more distal and transverse. Correlation analysis showed that bone strength was predominantly determined by aBMD with minor contributions from structure and intrinsic strength as measured by nanoindentation and cracks density. In contrast, fracture location was predicted equally by aBMD, crack density and intrinsic modulus. The data suggest that not only bone strength but also the fracture pattern depends on previous damage and the effects of bone turnover on bone mass and structure. These observations may be relevant to further understand the mechanisms contributing to fracture pattern in long bone with different levels of bone remodeling, including atypical femur fracture.

  4. Bare Code Reader

    NASA Astrophysics Data System (ADS)

    Clair, Jean J.

    1980-05-01

    The Bare code system will be used, in every market and supermarket. The code, which is normalised in US and Europe (code EAN) gives informations on price, storage, nature and allows in real time the gestion of theshop.

  5. Evolution in practice patterns and long-term outcomes of coronary revascularization from bare-metal stent era to drug-eluting stent era in Japan.

    PubMed

    Shiomi, Hiroki; Morimoto, Takeshi; Makiyama, Takeru; Ono, Koh; Furukawa, Yutaka; Nakagawa, Yoshihisa; Kadota, Kazushige; Onodera, Tomoya; Takatsu, Yoshiki; Mitsudo, Kazuaki; Kita, Toru; Sakata, Ryuzo; Okabayashi, Hitoshi; Hanyu, Michiya; Komiya, Tatsuhiko; Yamazaki, Fumio; Nishiwaki, Noboru; Kimura, Takeshi

    2014-05-15

    Treatment of coronary artery disease has significantly changed over the past decade including an introduction of drug-eluting stents and a more stringent adherence to evidence-based medications. However, the impact of these advanced treatment methods on the practice patterns and long-term outcomes in patients undergoing coronary revascularization in the real world has not been yet fully evaluated. The present study population consisted of the 2 groups of patients who underwent their first coronary revascularization in the Coronary REvascularization Demonstrating Outcome Study in Kyoto Registry Cohort-1 (bare-metal stent era: January 2000 to December 2002, n = 8,986) and Cohort-2 (drug-eluting stent era: January 2005 to December 2007, n = 10,339). Compared with Cohort-1, the proportion of patients treated with percutaneous coronary intervention significantly increased in Cohort-2 (73% vs 81%, p <0.001), particularly for 3-vessel disease (50% vs 61%, p <0.001) and left main disease (18% vs 36%, p <0.001). Evidence-based medications were more frequently used in Cohort-2. The cumulative 2-year incidence of and the adjusted risk for all-cause death were not significantly different between Cohort-1 and Cohort-2 (6.2% vs 6.4%, p = 0.69, and hazard ratio [HR] 0.91, 95% confidence interval [CI] 0.81 to 1.03, p = 0.15). Adjusted risks for both myocardial infarction and repeated coronary revascularization were significantly reduced in Cohort-2 compared with Cohort-1 (HR 0.80, 95% CI 0.67 to 0.96, p = 0.02, and HR 0.73, 95% CI 0.69 to 0.77, p <0.001, respectively). In conclusion, despite changes in treatment methods over time, the long-term mortality of patients undergoing coronary revascularization in the real-world clinical practice has not been changed, although there was a significant reduction of myocardial infarction and repeated coronary revascularization. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. [Dietary patterns in college freshmen and its relation to bone mineral density].

    PubMed

    Wang, Sufang; Mu, Min; Zhao, Yan; Wang, Xiaoqin; Shu, Long; Li, Qingyan; Li, Yingchun

    2012-07-01

    In order to investigate the bone density of freshmen, and to analyze the association between dietary pattern and bone mineral density (BMD). A questionnaire survey on the situation of dietary pattern was conducted in 1414 freshmen. Effective dietary survey questionnaires and bone mineral density measurements were completed for 1319 participants. Bone mass was assessed by using an Ultrasound Bone Densitometer on the right calcaneus (CM-200, Furuno Electric Corporation, Japan), and the speed of sound (SOS, m/s) was used as an indicator for bone density. Factor analysis with varimax rotation was used to identify the dietary patterns. After adjusting for confounders, covariance with Bonferroni's was used to further examine the associations between dietary patterns and bone mineral density (BMD). (1) Four major dietary patterns were noticed. Western food pattern (high consumption in hamburger, fried food, nuts, biscuit, chocolate, cola, coffee, sugars). Animal protein pattern (high consumption in pork, mutton, beef, poultry meat, animal liver). Calcium pattern (high consumption in fresh fruits, eggs, fish and shrimps, kelp laver and sea fish, milk and dairy products, beans and bean products). Traditional Chinese pattern (high consumption in rice and grain, fresh fruits, fresh vegetables, pork). (2) No association was observed between the western food pattern and bone mineral density. High animal protein pattern showed lower SOS value compared with low animal protein pattern. High calcium pattern showed higher SOS value compared with low calcium pattern. High traditional Chinese pattern showed higher SOS value compared with the low traditional Chinese pattern. Dietary patterns are closely related with bone mineral density (BMD) of freshmen.

  7. Coping patterns among bone marrow transplant patients: a hermeneutical inquiry.

    PubMed

    Shuster, G F; Steeves, R H; Onega, L; Richardson, B

    1996-08-01

    Bone marrow transplantation (BMT) has recently become the treatment of choice for a number of malignancies. This procedure is highly technical, involving the use of radiation and chemotherapy to destroy the patient's diseased bone marrow and with it functions of the entire immune system. It is a process with toxic effects that are experienced by all patients to varying degrees. A great deal of research related to the physiological aspects of this procedure has already been done, but considerably fewer studies have examined the psychosocial aspects of the BMT procedure from the patient's perspective. Knowledge about how BMT patients understand this process and cope with its effects is important information for nurses taking care of these patients. The purpose of the study was to describe in depth the patterns of meaning employed by patients in the hospital as they coped with the experience of their BMT. Eleven patients were interviewed from one to four times a week throughout their hospitalization. Hermeneutic analysis was used to identify five major themes: physiological functioning, alertness, attitude, social relationships, and spirituality. Implications from the findings for nursing practice are discussed.

  8. Spiral Galaxies Stripped Bare

    NASA Astrophysics Data System (ADS)

    2010-10-01

    Six spectacular spiral galaxies are seen in a clear new light in images from ESO's Very Large Telescope (VLT) at the Paranal Observatory in Chile. The pictures were taken in infrared light, using the impressive power of the HAWK-I camera, and will help astronomers understand how the remarkable spiral patterns in galaxies form and evolve. HAWK-I [1] is one of the newest and most powerful cameras on ESO's Very Large Telescope (VLT). It is sensitive to infrared light, which means that much of the obscuring dust in the galaxies' spiral arms becomes transparent to its detectors. Compared to the earlier, and still much-used, VLT infrared camera ISAAC, HAWK-I has sixteen times as many pixels to cover a much larger area of sky in one shot and, by using newer technology than ISAAC, it has a greater sensitivity to faint infrared radiation [2]. Because HAWK-I can study galaxies stripped bare of the confusing effects of dust and glowing gas it is ideal for studying the vast numbers of stars that make up spiral arms. The six galaxies are part of a study of spiral structure led by Preben Grosbøl at ESO. These data were acquired to help understand the complex and subtle ways in which the stars in these systems form into such perfect spiral patterns. The first image shows NGC 5247, a spiral galaxy dominated by two huge arms, located 60-70 million light-years away. The galaxy lies face-on towards Earth, thus providing an excellent view of its pinwheel structure. It lies in the zodiacal constellation of Virgo (the Maiden). The galaxy in the second image is Messier 100, also known as NGC 4321, which was discovered in the 18th century. It is a fine example of a "grand design" spiral galaxy - a class of galaxies with very prominent and well-defined spiral arms. About 55 million light-years from Earth, Messier 100 is part of the Virgo Cluster of galaxies and lies in the constellation of Coma Berenices (Berenice's Hair, named after the ancient Egyptian queen Berenice II). The third

  9. Healing pattern of reamed bone following bone harvesting by a RIA device.

    PubMed

    Devine, D M; Arens, D; Thalhauser, M; Schiuma, D; Zeiter, S; Nehrbass, D

    2015-01-29

    Intramedullary nailing has been used for decades to treat fractures of the long bones. However, complications related to the increase in medullary pressure culminated in the development of the Reamer Irrigator Aspirator (RIA). Since its first clinical use, the RIA has moved from a reaming device to a cell and autologous bone-harvesting tool. This increase in use brings with it further clinical questions; namely, does the endosteal bone regenerate sufficiently to allow subsequent reaming procedures. In the current study, endosteal bone regeneration post reaming was assessed in an ovine model. The study included six animals that had one tibia reamed, while the contralateral tibia acted as an intact control. Animals were administered fluorochrome labels in vivo, and bone regeneration was assessed using radiographical analysis. The endpoint of the study was 12 weeks post-surgery, at which time ex vivo analysis consisted of computed tomography and histological assessments. In vivo radiographs indicated limited healing of the reamed bone. However, ex vivo computer tomographical analysis indicated no significant differences in terms of bone volume between the reamed bone and the intact bone. Histological assessment of these regions indicated new bone formation. Fluorescent labelling indicates strong bone formation from 9 weeks post-surgery and as such, the bone formed at 12 weeks was immature in nature and was actively undergoing remodelling. These results indicate that bone regeneration post-reaming was continuing at three months. Therefore, given more time it may have sufficiently healed to allow a surgeon to use the intramedullary canal for a re-reaming procedure.

  10. Computational model-informed design and bioprinting of cell-patterned constructs for bone tissue engineering.

    PubMed

    Carlier, Aurélie; Skvortsov, Gözde Akdeniz; Hafezi, Forough; Ferraris, Eleonora; Patterson, Jennifer; Koç, Bahattin; Van Oosterwyck, Hans

    2016-05-17

    Three-dimensional (3D) bioprinting is a rapidly advancing tissue engineering technology that holds great promise for the regeneration of several tissues, including bone. However, to generate a successful 3D bone tissue engineering construct, additional complexities should be taken into account such as nutrient and oxygen delivery, which is often insufficient after implantation in large bone defects. We propose that a well-designed tissue engineering construct, that is, an implant with a specific spatial pattern of cells in a matrix, will improve the healing outcome. By using a computational model of bone regeneration we show that particular cell patterns in tissue engineering constructs are able to enhance bone regeneration compared to uniform ones. We successfully bioprinted one of the most promising cell-gradient patterns by using cell-laden hydrogels with varying cell densities and observed a high cell viability for three days following the bioprinting process. In summary, we present a novel strategy for the biofabrication of bone tissue engineering constructs by designing cell-gradient patterns based on a computational model of bone regeneration, and successfully bioprinting the chosen design. This integrated approach may increase the success rate of implanted tissue engineering constructs for critical size bone defects and also can find a wider application in the biofabrication of other types of tissue engineering constructs.

  11. Analysis of Long Bone and Vertebral Failure Patterns.

    DTIC Science & Technology

    1983-03-01

    A region of fractured and collapsed trabeculae above the nucleus pulposus was consistently observed in impacted animals. The disc is thought to...cartilaginous end plate. The cartilaginous endplate consisted of three morphologic regions (Fig. 3). Next to the trabecular bone were areas of strongly alcian...blue regions was a zone of calcified cartilage. A basophilic line separated areas of contact of the calcified cartilage with the trabecular bone of the

  12. Long bone histology and growth patterns in ankylosaurs: implications for life history and evolution.

    PubMed

    Stein, Martina; Hayashi, Shoji; Sander, P Martin

    2013-01-01

    The ankylosaurs are one of the major dinosaur groups and are characterized by unique body armor. Previous studies on other dinosaur taxa have revealed growth patterns, life history and evolutionary mechanisms based on their long bone histology. However, to date nothing is known about long bone histology in the Ankylosauria. This study is the first description of ankylosaurian long bone histology based on several limb elements, which were sampled from different individuals from the Ankylosauridae and Nodosauridae. The histology is compared to that of other dinosaur groups, including other Thyreophora and Sauropodomorpha. Ankylosaur long bone histology is characterized by a fibrolamellar bone architecture. The bone matrix type in ankylosaurs is closest to that of Stegosaurus. A distinctive mixture of woven and parallel-fibered bone together with overall poor vascularization indicates slow growth rates compared to other dinosaurian taxa. Another peculiar characteristic of ankylosaur bone histology is the extensive remodeling in derived North American taxa. In contrast to other taxa, ankylosaurs substitute large amounts of their primary tissue early in ontogeny. This anomaly may be linked to the late ossification of the ankylosaurian body armor. Metabolically driven remodeling processes must have liberated calcium to ossify the protective osteodermal structures in juveniles to subadult stages, which led to further remodeling due to increased mechanical loading. Abundant structural fibers observed in the primary bone and even in remodeled bone may have improved the mechanical properties of the Haversian bone.

  13. Long Bone Histology and Growth Patterns in Ankylosaurs: Implications for Life History and Evolution

    PubMed Central

    Stein, Martina; Hayashi, Shoji; Sander, P. Martin

    2013-01-01

    The ankylosaurs are one of the major dinosaur groups and are characterized by unique body armor. Previous studies on other dinosaur taxa have revealed growth patterns, life history and evolutionary mechanisms based on their long bone histology. However, to date nothing is known about long bone histology in the Ankylosauria. This study is the first description of ankylosaurian long bone histology based on several limb elements, which were sampled from different individuals from the Ankylosauridae and Nodosauridae. The histology is compared to that of other dinosaur groups, including other Thyreophora and Sauropodomorpha. Ankylosaur long bone histology is characterized by a fibrolamellar bone architecture. The bone matrix type in ankylosaurs is closest to that of Stegosaurus. A distinctive mixture of woven and parallel-fibered bone together with overall poor vascularization indicates slow growth rates compared to other dinosaurian taxa. Another peculiar characteristic of ankylosaur bone histology is the extensive remodeling in derived North American taxa. In contrast to other taxa, ankylosaurs substitute large amounts of their primary tissue early in ontogeny. This anomaly may be linked to the late ossification of the ankylosaurian body armor. Metabolically driven remodeling processes must have liberated calcium to ossify the protective osteodermal structures in juveniles to subadult stages, which led to further remodeling due to increased mechanical loading. Abundant structural fibers observed in the primary bone and even in remodeled bone may have improved the mechanical properties of the Haversian bone. PMID:23894321

  14. Current Evidence on the Association of Dietary Patterns and Bone Health: A Scoping Review.

    PubMed

    Movassagh, Elham Z; Vatanparast, Hassan

    2017-01-01

    Nutrition is an important modifiable factor that affects bone health. Diet is a complex mixture of nutrients and foods that correlate or interact with each other. Dietary pattern approaches take into account contributions from various aspects of diet. Findings from dietary pattern studies could complement those from single-nutrient and food studies on bone health. In this study we aimed to conduct a scoping review of the literature that assessed the impact of dietary patterns (derived with the use of both a priori and data-driven approaches) on bone outcomes, including bone mineral status, bone biomarkers, osteoporosis, and fracture risk. We retrieved 49 human studies up to June 2016 from the PubMed, Embase, and CINAHL databases. Most of these studies used a data-driven method, especially factor analysis, to derive dietary patterns. Several studies examined adherence to a variety of the a priori dietary indexes, including the Mediterranean diet score, the Healthy Eating Index (HEI), and the Alternative Healthy Eating Index (AHEI). The bone mineral density (BMD) diet score was developed to measure adherence to a dietary pattern beneficial to bone mineral density. Findings revealed a beneficial impact of higher adherence to a "healthy" dietary pattern derived using a data-driven method, the Mediterranean diet, HEI, AHEI, Dietary Diversity Score, Diet Quality Index-International, BMD Diet Score, Healthy Diet Indicator, and Korean Diet Score, on bone. In contrast, the "Western" dietary pattern and those featuring some aspects of an unhealthy diet were associated inversely with bone health. In both a priori and data-driven dietary pattern studies, a dietary pattern that emphasized the intake of fruit, vegetables, whole grains, poultry and fish, nuts and legumes, and low-fat dairy products and de-emphasized the intake of soft drinks, fried foods, meat and processed products, sweets and desserts, and refined grains showed a beneficial impact on bone health. Overall

  15. Bone weathering patterns of metatarsal v. femur and the postmortem interval in Southern Ontario.

    PubMed

    Janjua, Martyna A; Rogers, Tracy L

    2008-06-10

    Twenty-five defleshed pig femora and 25 metatarsals were placed outdoors and observed over 291 days to establish: (1) bone weathering patterns for use in estimating time since death in Southern Ontario and (2) whether larger (femora) or smaller (metatarsals) bones provide a better indicator of time since death. Pig hind limbs were observed to determine a timeline for decomposition of soft tissues during the fall and winter. Ambient air temperature, humidity, precipitation, sunlight, soil pH, and freezing and thawing were considered as factors affecting the breakdown of bone. Weathering patterns were observed based on the extent of bleaching, amount of periosteum and soft tissues present, as well as the appearance of greasiness, cracking and flaking of cortical bone. Both entomological activity and climatic conditions affected soft tissue decomposition. Animal activity affected both the process of bone weathering and soft tissue decomposition, causing variability in sample decomposition and bone breakdown. The variation in microenvironment, partially caused by soil composition, introduced variability in bone weathering rates. Four bone weathering stages were established based on patterns observed. Femora proved to be more resilient and showed more degrees of change due to weathering, thus proving to be a better indicator of time since death than metatarsals.

  16. Bone marrow edema pattern identification in patients with lytic bone lesions using digital subtraction angiography-like bone subtraction on large-area detector computed tomography.

    PubMed

    Gondim Teixeira, Pedro Augusto; Hossu, Gabriela; Lecocq, Sophie; Razeto, Marco; Louis, Matthias; Blum, Alain

    2014-03-01

    The objective of this study was to evaluate the performance of digital subtraction angiography (DSA)-like bone subtraction with 2 different registration methods for the identification of bone marrow edema pattern (BMEP) in patients with lytic bone lesions, using magnetic resonance imaging as the criterion standard. Fifty-five patients with a lytic bone lesion were included in this prospective study with approval from the ethics committee. All patients underwent magnetic resonance imaging and low-dose computed tomographic (CT) perfusion after signing an informed consent. Two CT volumes were used for bone subtraction, which was performed with 2 different algorithms (rigid and nonrigid). Enhancement at the nonlytic bone marrow was considered as a sign of BMEP. Two readers evaluated the images blindly. The presence of BMEP on bone-subtracted CT images was evaluated subjectively and quantitatively. Image quality was assessed. Magnetic resonance imaging was used as the criterion standard. Using a rigid registration method, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CT with DSA-like bone subtraction BMEP was 77%, 100%, 100%, 68%, and 85%, respectively. The interobserver agreement was good (κ, 0.782). Image quality was better using a nonrigid registration. With this algorithm, artifacts interfered with image interpretation in only 5% of cases. However, there was a noticeable drop in sensitivity and negative predictive value when a nonrigid algorithm was used: 56% and 52%, respectively. The interobserver agreement was average with a nonrigid subtraction algorithm. Computed tomography with DSA-like bone subtraction is sensitive and highly specific for the identification of BMEP associated with lytic bone lesions. Rigid registering should be preferred, but nonrigid algorithms can be used as a second option when artifacts interfere with image interpretation.

  17. Effect of soil type patterns on the variability of bare soil evaporation within a field: comparison of eddy covariance measurements with potential and actual evaporation calculations

    NASA Astrophysics Data System (ADS)

    Vanderborght, J.; Graf, A.; Steenpass, C.; Scharnagl, B.; Prolingheuer, N.; Herbst, M.; Vereecken, H.

    2009-12-01

    Bare soil evaporation was measured with the eddy-covariance method at the Selhausen field site. The site has a distinct gradient in soil texture with a considerably higher stone content at the upper part of the field. Because of this gradient, a spatial variation in evaporation fluxes in the field is expected. Because of the higher stone content at the upper part of the field, it is expected that the water that is stored in the soil surface layer and can be evaporated at a maximal evaporation rate, which is determined by the energy that is available for evaporation, is considerable smaller in the upper than in the lower part of the field. We investigated whether this hypothesis is supported by eddy covariance (EC) measurements of the evaporation fluxes at the field site. The EC measurements were combined with a footprint model that predicts the location of the soil surface that contributes to the measured evaporation flux. In this way, evaporation measurements of the two parts of the field site could be distinguished. However, since only one EC station was available, simultaneous evaporation measurements for the two field parts were not available. As a consequence, the datasets of measurements had to be interpreted and put into context of the meteorological and soil hydrological conditions. The potential evapotranspiration was calculated using the FAO method (Allen et al., 1998) to represent the meteorological conditions whereas a simple soil evaporation model (Boesten and Stroosnijder, 1986) was used to represent the influence of the precipitation and soil hydrological conditions on the actual evaporation rate. Since different soil parameters were required to describe the evaporation measurements for the upper and lower part of the plot, our starting hypothesis that more water is evaporated in the lower part of the field could be confirmed. Allen, R. G., L. S. Pereira, D. Raes, and M. Smith (1998), Crop evapotranspiration: Guidelines for computing crop water

  18. Stretch force guides finger-like pattern of bone formation in suture

    PubMed Central

    Kou, Xiao-Xing; Zhang, Ci; Zhang, Yi-Mei; Cui, Zhen; Wang, Xue-Dong; Liu, Yan; Liu, Da-Wei; Zhou, Yan-Heng

    2017-01-01

    Mechanical tension is widely applied on the suture to modulate the growth of craniofacial bones. Deeply understanding the features of bone formation in expanding sutures could help us to improve the outcomes of clinical treatment and avoid some side effects. Although there are reports that have uncovered some biological characteristics, the regular pattern of sutural bone formation in response to expansion forces is still unknown. Our study was to investigate the shape, arrangement and orientation of new bone formation in expanding sutures and explore related clinical implications. The premaxillary sutures of rat, which histologically resembles the sutures of human beings, became wider progressively under stretch force. Micro-CT detected new bones at day 3. Morphologically, these bones were forming in a finger-like pattern, projecting from the maxillae into the expanded sutures. There were about 4 finger-like bones appearing on the selected micro-CT sections at day 3 and this number increased to about 18 at day 7. The average length of these projections increased from 0.14 mm at day 3 to 0.81 mm at day 7. The volume of these bony protuberances increased to the highest level of 0.12 mm3 at day 7. HE staining demonstrated that these finger-like bones had thick bases connecting with the maxillae and thin fronts stretching into the expanded suture. Nasal sections had a higher frequency of finger-like bones occuring than the oral sections at day 3 and day 5. Masson-stained sections showed stretched fibers embedding into maxillary margins. Osteocalcin-positive osteoblasts changed their shapes from cuboidal to spindle and covered the surfaces of finger-like bones continuously. Alizarin red S and calcein deposited in the inner and outer layers of finger-like bones respectively, which showed that longer and larger bones formed on the nasal side of expanded sutures compared with the oral side. Interestingly, these finger-like bones were almost paralleling with the direction

  19. Identification of a dietary pattern prospectively associated with bone mass in Australian young adults.

    PubMed

    van den Hooven, Edith H; Ambrosini, Gina L; Huang, Rae-Chi; Mountain, Jenny; Straker, Leon; Walsh, John P; Zhu, Kun; Oddy, Wendy H

    2015-11-01

    Relatively little is known about the relations between dietary patterns and bone health in adolescence, which is a period of substantial bone mass accrual. We derived dietary patterns that were hypothesized to be related to bone health on the basis of their protein, calcium, and potassium contents and investigated their prospective associations with bone mineral density (BMD), bone area, and bone mineral content (BMC) in a cohort of young adults. The study included 1024 young adults born to mothers who were participating in the Western Australian Pregnancy Cohort (Raine) Study. Dietary information was obtained from food-frequency questionnaires at 14 and 17 y of age. Dietary patterns were characterized according to protein, calcium, and potassium intakes with the use of reduced-rank regression. BMD, bone area, and BMC were estimated with the use of a total body dual-energy X-ray absorptiometry scan at 20 y of age. We identified 2 major dietary patterns. The first pattern was positively correlated with intakes of protein, calcium, and potassium and had high factor loadings for low-fat dairy products, whole grains, and vegetables. The second pattern was positively correlated with protein intake but negatively correlated with intakes of calcium and potassium and had high factor loadings for meat, poultry, fish, and eggs. After adjustment for anthropometric, sociodemographic, and lifestyle factors, a higher z score for the first pattern at 14 y of age was positively associated with BMD and BMC at 20 y of age [differences: 8.6 mg/cm(2) (95% CI: 3.0, 14.1 mg/cm(2)) and 21.9 g (95% CI: 6.5, 37.3 g), respectively, per SD increase in z score]. The z score for this same pattern at 17 y of age was not associated with bone outcomes at 20 y of age. The second pattern at 14 or 17 y of age was not associated with BMD, BMC, or bone area. A dietary pattern characterized by high intakes of protein, calcium, and potassium in midadolescence was associated with higher BMD and BMC at 20

  20. Multidisciplinary characterization of the long-bone cortex growth patterns through sheep's ontogeny.

    PubMed

    Cambra-Moo, Oscar; Nacarino-Meneses, Carmen; Díaz-Güemes, Idoia; Enciso, Silvia; García Gil, Orosia; Llorente Rodríguez, Laura; Rodríguez Barbero, Miguel Ángel; de Aza, Antonio H; González Martín, Armando

    2015-07-01

    Bone researches have studied extant and extinct taxa extensively trying to disclose a complete view of the complex structural and chemical transformations that model and remodel the macro and microstructure of bone during growth. However, to approach bone growth variations is not an easy task, and many aspects related with histological transformations during ontogeny remain unresolved. In the present study, we conduct a holistic approach using different techniques (polarized microscopy, Raman spectroscopy and X-ray diffraction) to examine the histomorphological and histochemical variations in the cortical bone of sheep specimens from intrauterine to adult stages, using environmentally controlled specimens from the same species. Our results suggest that during sheep bone development, the most important morphological (shape and size) and chemical transformations in the cortical bone occur during the first weeks of life; synchronized but dissimilar variations are established in the forelimb and hind limb cortical bone; and the patterns of bone tissue maturation in both extremities are differentiated in the adult stage. All of these results indicate that standardized histological models are useful not only for evaluating many aspects of normal bone growth but also to understand other important influences on the bones, such as pathologies that remain unknown. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Bone modeling patterns and morphometric craniofacial variation in individuals from two prehistoric human populations from Argentina.

    PubMed

    Brachetta Aporta, Natalia; Martinez-Maza, Cayetana; Gonzalez, Paula N; Bernal, Valeria

    2014-10-01

    Native human populations from South America display high levels of craniofacial variation encompassing gracile and robust skulls. Nevertheless, the processes of bone modeling by which morphological variation among populations were attained, remain poorly understood. Here we analyze the relationship between patterns of bone formation and resorption and morphometric variation in the upper face of adults belonging to farmers and hunter-gatherers from northwestern and south Argentina. Our analyses reveal a common pattern of bone modeling of the malar bone characterized by the presence of formation areas. Thus, the larger size and greater development of malar bone exhibited by hunter-gatherers would be linked to a greater magnitude of bone formation activity. Conversely, the glabella and the superciliary arch presented both formation and resorption areas with a variable distribution among individuals. In the extreme corresponding to more robust morphologies, the great development of the glabella is related to the presence of large formation fields, both in the upper region and toward the frontonasal suture. The less robust morphologies show resorption fields at the upper margin of the glabella, which would contribute to the weaker development of this region. The superciliary arch showed a complex relationship between its morphometric and histological variation; the individuals located at both extremes of the shape space presented large resorption areas located on its upper margin. Overall, our results show the existence of intraspecific variation in the patterns of bone modeling in the human upper face. © 2014 Wiley Periodicals, Inc.

  2. Barely Bisected Rings

    NASA Image and Video Library

    2016-09-12

    Saturn's shadow stretched beyond the edge of its rings for many years after Cassini first arrived at Saturn, casting an ever-lengthening shadow that reached its maximum extent at the planet's 2009 equinox. This image captured the moment in 2015 when the shrinking shadow just barely reached across the entire main ring system. The shadow will continue to shrink until the planet's northern summer solstice, at which point it will once again start lengthening across the rings, reaching across them in 2019. Like Earth, Saturn is tilted on its axis. And, just as on Earth, as the sun climbs higher in the sky, shadows get shorter. The projection of the planet's shadow onto the rings shrinks and grows over the course of its 29-year-long orbit, as the angle of the sun changes with respect to Saturn's equator. This view looks toward the sunlit side of the rings from about 11 degrees above the ring plane. The image was taken in visible light with the Cassini spacecraft wide-angle camera on Jan. 16, 2015. The view was obtained at a distance of approximately 1.6 million miles (2.5 million kilometers) from Saturn. Image scale is about 90 miles (150 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA20498

  3. Apparent density patterns in subchondral bone of the sloth and anteater forelimb.

    PubMed

    Patel, Biren A; Carlson, Kristian J

    2008-10-23

    Vertebrate morphologists often are interested in inferring limb-loading patterns in animals characterized by different locomotor repertoires. Because bone apparent density (i.e. mass per unit volume of bone inclusive of porosities) is a determinant of compressive strength, and thus indicative of compressive loading, recent comparative studies in primates have proposed a structure-function relationship between apparent density of subchondral bone and locomotor behaviours that vary in compressive loading. If such patterns are found in other mammals, then these relationships would be strengthened further. Here, we examine the distal radius of suspensory sloths that generally load their forelimbs (FLs) in tension and of quadrupedal anteaters that generally load their FLs in compression. Computed tomography osteoabsorptiometry was used to visualize the patterns in subchondral apparent density. Suspensory sloths exhibit relatively smaller areas of high apparent density than quadrupedal anteaters. This locomotor-based pattern is analogous to the pattern observed in suspensory and quadrupedal primates. Similarity between xenarthran and primate trends suggests broad-scale applicability for analysing subchondral bone apparent density and supports the idea that bone functionally alters its material properties in response to locomotor behaviours.

  4. Growth patterns of fossil vertebrates as deduced from bone microstructure: case studies from India.

    PubMed

    Ray, S; Mukherjee, D; Bandyopadhyay, S

    2009-11-01

    Bone microstructure is affected by ontogeny, phylogeny, biomechanics and environments. These aspects of life history of an extinct animal, especially its growth patterns, may be assessed as fossil bone generally maintains its histological integrity. Recent studies on the bone histology of fossil vertebrates from India encompass different types of temnospondyls and dicynodonts from different Permian and Triassic horizons. The examined taxa show that they had distinct bone histology and varied growth patterns. The Early Triassic trematosaurids had an overall fast growth, which contrasts with that of the Middle and Late Triassic temnospondyl taxa examined. The dicynodonts on the other hand, were characterized by an overall fast growth with periodic interruptions, variable growth rates dependent on ontogeny and indeterminate growth strategy. A comparative study encompassing several neotherapsid genera including the dicynodonts shows signifi cant evolutionary trends towards determinate growth strategy and reduced developmental plasticity.

  5. Bone histology. Evolution of growth pattern in birds.

    PubMed

    Chinsamy, A; Elzanowski, A

    2001-07-26

    Living (neornithine) birds grow up rapidly and without interruption, terminating their growth within one year and, with a few secondary exceptions, starting to fly only after or near the completion of growth. Bone histology has revealed that pre-avian theropods also grew fast for most of the postnatal period, but that this growth was usually intermittent and probably extended for more than one year. We have found surprising evidence for an early postnatal slowing-down of growth in two lineages of flying basal birds, which suggests that birds may have started their evolution as precocious fliers.

  6. Dietary patterns and bone mineral status in young adults: the Northern Ireland Young Hearts Project.

    PubMed

    Whittle, Claire R; Woodside, Jayne V; Cardwell, Chris R; McCourt, Hannah J; Young, Ian S; Murray, Liam J; Boreham, Colin A; Gallagher, Alison M; Neville, Charlotte E; McKinley, Michelle C

    2012-10-28

    Studies of individual nutrients or foods have revealed much about dietary influences on bone. Multiple food or nutrient approaches, such as dietary pattern analysis, could offer further insight but research is limited and largely confined to older adults. We examined the relationship between dietary patterns, obtained by a posteriori and a priori methods, and bone mineral status (BMS; collective term for bone mineral content (BMC) and bone mineral density (BMD)) in young adults (20-25 years; n 489). Diet was assessed by 7 d diet history and BMD and BMC were determined at the lumbar spine and femoral neck (FN). A posteriori dietary patterns were derived using principal component analysis (PCA) and three a priori dietary quality scores were applied (dietary diversity score (DDS), nutritional risk score and Mediterranean diet score). For the PCA-derived dietary patterns, women in the top compared to the bottom fifth of the 'Nuts and Meat' pattern had greater FN BMD by 0·074 g/cm(2) (P = 0·049) and FN BMC by 0·40 g (P = 0·034) after adjustment for confounders. Similarly, men in the top compared to the bottom fifth of the 'Refined' pattern had lower FN BMC by 0·41 g (P = 0·049). For the a priori DDS, women in the top compared to the bottom third had lower FN BMD by 0·05 g/cm(2) after adjustments (P = 0·052), but no other relationships with BMS were identified. In conclusion, adherence to a 'Nuts and Meat' dietary pattern may be associated with greater BMS in young women and a 'Refined' dietary pattern may be detrimental for bone health in young men.

  7. Inter-dependent tissue growth and Turing patterning in a model for long bone development

    NASA Astrophysics Data System (ADS)

    Tanaka, Simon; Iber, Dagmar

    2013-10-01

    The development of long bones requires a sophisticated spatial organization of cellular signalling, proliferation, and differentiation programs. How such spatial organization emerges on the growing long bone domain is still unresolved. Based on the reported biochemical interactions we developed a regulatory model for the core signalling factors IHH, PTCH1, and PTHrP and included two cell types, proliferating/resting chondrocytes and (pre-)hypertrophic chondrocytes. We show that the reported IHH-PTCH1 interaction gives rise to a Schnakenberg-type Turing kinetics, and that inclusion of PTHrP is important to achieve robust patterning when coupling patterning and tissue dynamics. The model reproduces relevant spatiotemporal gene expression patterns, as well as a number of relevant mutant phenotypes. In summary, we propose that a ligand-receptor based Turing mechanism may control the emergence of patterns during long bone development, with PTHrP as an important mediator to confer patterning robustness when the sensitive Turing system is coupled to the dynamics of a growing and differentiating tissue. We have previously shown that ligand-receptor based Turing mechanisms can also result from BMP-receptor, SHH-receptor, and GDNF-receptor interactions, and that these reproduce the wildtype and mutant patterns during digit formation in limbs and branching morphogenesis in lung and kidneys. Receptor-ligand interactions may thus constitute a general mechanism to generate Turing patterns in nature.

  8. Referral patterns of general dental practitioners for bone grafting and implant placement.

    PubMed

    Gupta, B; Shadbolt, B; Hyam, D

    2017-09-01

    Dental implant rehabilitation is a well-established procedure often conducted in the general dental practise setting. The outcomes for implant placement are reliable when the recipient site is favourable. The goal of this study was to assess the accuracy with which general dental practitioners (GDP) assess the bone volume available for implant placement and their referral patterns for implant sites, which may require bone grafting. Fifty-three GDP were surveyed and asked to assess five different scenarios and cone-beam scans for difficulty (0, 'no difficulty'; 5, 'the most difficult'), and bone grafting requirements ('yes'/'no' and 'who to perform'), prior to implant placement. The GDP assessment of difficulty for the cases was: no graft required, 1.88; aesthetic zone involvement, 3.25; vertical deficiency, 2.8; sinus lift required, 3.68; and horizontal deficiency, 4.4. GDP seemed to have some difficulty identifying which cases required a bone graft, occasionally grafting a site with sufficient bone (12.5%), or not grafting a site with insufficient bone (45-75%). These results show that GDP are accurate in assessing the difficulty of an implant case and conservative when it comes to attempting these complex cases. GDP are less confident when it comes to recognizing cases that require bone grafting, and what options are available. © 2017 Australian Dental Association.

  9. Dietary patterns in men and women are simultaneously determinants of altered glucose metabolism and bone metabolism.

    PubMed

    Langsetmo, Lisa; Barr, Susan I; Dasgupta, Kaberi; Berger, Claudie; Kovacs, Christopher S; Josse, Robert G; Adachi, Jonathan D; Hanley, David A; Prior, Jerilynn C; Brown, Jacques P; Morin, Suzanne N; Davison, Kenneth S; Goltzman, David; Kreiger, Nancy

    2016-04-01

    We hypothesized that diet would have direct effects on glucose metabolism with direct and indirect effects on bone metabolism in a cohort of Canadian adults. We assessed dietary patterns (Prudent [fruit, vegetables, whole grains, fish, and legumes] and Western [soft drinks, potato chips, French fries, meats, and desserts]) from a semiquantitative food frequency questionnaire. We used fasting blood samples to measure glucose, insulin, homeostatic model assessment insulin resistance (HOMA-IR), 25-hydroxyvitamin D (25OHD), parathyroid hormone, bone-specific alkaline phosphatase (a bone formation marker), and serum C-terminal telopeptide (CTX; a bone resorption marker). We used multivariate regression models adjusted for confounders and including/excluding body mass index. In a secondary analysis, we examined relationships through structural equations models. The Prudent diet was associated with favorable effects on glucose metabolism (lower insulin and HOMA-IR) and bone metabolism (lower CTX in women; higher 25OHD and lower parathyroid hormone in men). The Western diet was associated with deleterious effects on glucose metabolism (higher glucose, insulin, and HOMA-IR) and bone metabolism (higher bone-specific alkaline phosphatase and lower 25OHD in women; higher CTX in men). Body mass index adjustment moved point estimates toward the null, indicating partial mediation. The structural equation model confirmed the hypothesized linkage with strong effects of Prudent and Western diet on metabolic risk, and both direct and indirect effects of a Prudent diet on bone turnover. In summary, a Prudent diet was associated with lower metabolic risk with both primary and mediated effects on bone turnover, suggesting that it is a potential target for reducing fracture risk. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Acquisition of Structure and Interpretation: Cases from Mandarin Bare and Non-Bare Noun Phrases

    ERIC Educational Resources Information Center

    Chang, Hsiang-Hua

    2011-01-01

    Children's production of bare nominals is universal. When acquiring languages disallowing bare nominals, children will develop from the bare to the non-bare stage. However, Mandarin nominals may appear bare or non-bare in various positions with all kinds of interpretations. This dissertation conducts two acquisition studies to examine the…

  11. Acquisition of Structure and Interpretation: Cases from Mandarin Bare and Non-Bare Noun Phrases

    ERIC Educational Resources Information Center

    Chang, Hsiang-Hua

    2011-01-01

    Children's production of bare nominals is universal. When acquiring languages disallowing bare nominals, children will develop from the bare to the non-bare stage. However, Mandarin nominals may appear bare or non-bare in various positions with all kinds of interpretations. This dissertation conducts two acquisition studies to examine the…

  12. Life Course Dietary Patterns and Bone Health in Later Life in a British Birth Cohort Study

    PubMed Central

    Prentice, Ann; Kuh, Diana L; Adams, Judith E; Ambrosini, Gina L

    2016-01-01

    ABSTRACT Evidence for the contribution of individual foods and nutrients to bone health is weak. Few studies have considered hypothesis‐based dietary patterns and bone health. We investigated whether a protein‐calcium‐potassium–rich (PrCaK‐rich) dietary pattern over the adult life course, was positively associated with bone outcomes at 60 to 64 years of age. Diet diaries were collected at ages 36, 46, 53, and 60 to 64 years in 1263 participants (661 women) from the MRC National Survey of Health and Development. DXA and pQCT measurements were obtained at age 60 to 64 years, including size‐adjusted bone mineral content (SA‐BMC) and volumetric bone mineral density (vBMD). A food‐based dietary pattern best explaining dietary calcium, potassium, and protein intakes (g/1000 kcal) was identified using reduced rank regression. Dietary pattern Z‐scores were calculated for each individual, at each time point. Individual trajectories in dietary pattern Z‐scores were modeled to summarize changes in Z‐scores over the study period. Regression models examined associations between these trajectories and bone outcomes at age 60 to 64 years, adjusting for baseline dietary pattern Z‐score and other confounders. A consistent PrCaK‐rich dietary pattern was identified within the population, over time. Mean ± SD dietary pattern Z‐scores at age 36 years and age 60 to 64 years were –0.32 ± 0.97 and 2.2 ± 1.5 (women) and –0.35 ± 0.98 and 1.7 ± 1.6 (men), respectively. Mean trajectory in dietary pattern Z‐scores ± SD was 0.07 ± 0.02 units/year. Among women, a 0.02‐SD unit/year higher trajectory in dietary pattern Z‐score over time was associated with higher SA‐BMC (spine 1.40% [95% CI, 0.30 to 2.51]; hip 1.35% [95% CI, 0.48 to 2.23]), and vBMD (radius 1.81% [95% CI, 0.13 to 3.50]) at age 60 to 64 years. No statistically significant associations were found in men. During adulthood, an increasing score for a dietary

  13. Lacunarity analysis of spatial pattern in CT images of vertebral trabecular bone for assessing osteoporosis.

    PubMed

    Dougherty, Geoffrey; Henebry, Geoffrey M

    2002-03-01

    The structural integrity of vertebral trabecular bone is determined by the continuity of its trabecular network and the size of the holes comprising its marrow space, both of which determine the apparent size of the marrow spaces in a transaxial CT image. A model-independent assessment of the trabeculation pattern was determined from the lacunarity of thresholded CT images. Using test images of lumbar vertebrae from human cadavers, acquired at different slice thicknesses, we determined that both median thresholding and local adaptive thresholding (using a 7 x 7 window) successfully segmented the grey-scale images. Lacunarity analysis indicated a multifractal nature to the images, and a range of marrow space sizes with significant structure around 14-18 mm(2). Preliminary studies of in vivo images from a clinical CT scanner indicate that lacunarity analysis can follow the pattern of bone loss in osteoporosis by monitoring the homogeneity of the marrow spaces, which is related to the connectivity of the trabecular bone network and the marrow space sizes. Although the patient sample was small, derived parameters such as the maximum deviation of the lacunarity from a neutral (fractal) model, and the maximum derivative of this deviation, seem to be sufficiently sensitive to distinguish a range of bone conditions. Our results suggest that these parameters, used with bone mineral density values, may have diagnostic value in characterizing osteoporosis and predicting fracture risk.

  14. An application of partial least squares for identifying dietary patterns in bone health.

    PubMed

    Yang, Tiffany C; Aucott, Lorna S; Duthie, Garry G; Macdonald, Helen M

    2017-12-01

    In a large cohort of older women, a mechanism-driven statistical technique for assessing dietary patterns that considers a potential nutrient pathway found two dietary patterns associated with lumbar spine and femoral neck bone mineral density. A "healthy" dietary pattern was observed to be beneficial for bone mineral density. Dietary patterns represent a broader, more realistic representation of how foods are consumed, compared to individual food or nutrient analyses. Partial least-squares (PLS) is a data-reduction technique for identifying dietary patterns that maximizes correlation between foods and nutrients hypothesized to be on the path to disease, is more hypothesis-driven than previous methods, and has not been applied to the study of dietary patterns in relation to bone health. Women from the Aberdeen Prospective Osteoporosis Screening Study (2007-2011, n = 2129, age = 66 years (2.2)) provided dietary intake using a food frequency questionnaire; 37 food groups were created. We applied PLS to the 37 food groups and 9 chosen response variables (calcium, potassium, vitamin C, vitamin D, protein, alcohol, magnesium, phosphorus, zinc) to identify dietary patterns associated with bone mineral density (BMD) cross-sectionally. Multivariable regression was used to assess the relationship between the retained dietary patterns and BMD at the lumbar spine and femoral neck, adjusting for age, body mass index, physical activity level, smoking, and national deprivation category. Five dietary patterns were identified, explaining 25% of the variation in food groups and 77% in the response variables. Two dietary patterns were positively associated with lumbar spine (per unit increase in factor 2: 0.012 g/cm(2) [95% CI: 0.006, 0.01]; factor 4: 0.007 g/cm(2) [95% CI: 0.00001, 0.01]) and femoral neck (factor 2: 0.006 g/cm(2) [95% CI: 0.002, 0.01]; factor 4: 0.008 g/cm(2) [95% CI: 0.003, 0.01)]) BMD. Dietary pattern 2 was characterized by high intakes of milk

  15. Inverse immunostaining pattern for synthesized versus endocytosed alpha-granule proteins in human bone marrow megakaryocytes.

    PubMed

    de Larouzière, V; Brouland, J P; Souni, F; Drouet, L; Cramer, E

    1998-06-01

    The time of appearance and pattern of expression of several alpha-granule proteins, von Willebrand factor (VWF), fibrinogen and immunoglobulins (Ig) were examined and compared in human bone marrow megakaryocytes (MK) using an immunocytochemical approach. VWF is synthesized by immature MK, whereas it has been shown that fibrinogen is incorporated from the plasma into alpha-granules. The present study was undertaken in order to determine whether there are chronological and morphological differences in the expression of VWF and fibrinogen in vivo in human MK. Seven paraffin-embedded biopsies of normal human bone marrow were labelled with specific antibodies for VWF and for fibrinogen, detected by the alkaline phosphatase anti-alkaline phosphatase (APAAP) method. and analysed by immunomorphometry. We found a clear, statistically significant. difference in the labelling pattern of VWF and fibrinogen. The expression of other endocytosed alpha-granule proteins, immunoglobulins G and A, was therefore studied in bone marrow MK from two patients with multiple myeloma, one with monoclonal IgG and one with monoclonal IgA. The immunostaining pattern was similar to that of fibrinogen and different from VWF, and characteristic of endocytosed alpha-granule proteins. This study demonstrates that: (i) immunohistochemical staining of MK alpha-granules proteins distinguishes the peripheral cockade distribution pattern of endocytosed protein from the perinuclear pattern of endogenously synthesized proteins; (ii) VWF is present in human bone marrow MK when fibrinogen is not yet detectable: (iii) VWF synthesis ceases while fibrinogen is still being incorporated: (iv) immunoglobulins can be detected in MK cytoplasm, with a staining pattern resembling that of fibrinogen.

  16. Maternal dietary patterns during pregnancy and childhood bone mass: a longitudinal study.

    PubMed

    Cole, Zoe A; Gale, Catharine R; Javaid, M Kassim; Robinson, Sian M; Law, Catherine; Boucher, Barbara J; Crozier, Sarah R; Godfrey, Keith M; Dennison, Elaine M; Cooper, Cyrus

    2009-04-01

    Maternal nutrition is a potentially important determinant of intrauterine skeletal development. Previous studies have examined the effects of individual nutrients, but the pattern of food consumption may be of greater relevance. We therefore examined the relationship between maternal dietary pattern during pregnancy and bone mass of the offspring at 9 yr of age. We studied 198 pregnant women 17-43 yr of age and their offspring at 9 yr of age. Dietary pattern was assessed using principal component analysis from a validated food frequency questionnaire. The offspring underwent measurements of bone mass using DXA at 9 yr of age. A high prudent diet score was characterized by elevated intakes of fruit, vegetables, and wholemeal bread, rice, and pasta and low intakes of processed foods. Higher prudent diet score in late pregnancy was associated with greater (p < 0.001) whole body and lumbar spine BMC and areal BMD in the offspring, after adjustment for sex, socioeconomic status, height, arm circumference, maternal smoking, and vitamin D status. Associations with prudent diet score in early pregnancy were weaker and nonsignificant. We conclude that dietary patterns consistent with current advice for healthy eating during pregnancy are associated with greater bone size and BMD in the offspring at 9 yr of age.

  17. Rural-Urban Differences of Dietary Patterns, Overweight, and Bone Mineral Status in Chinese Students

    PubMed Central

    Yang, Yang; Hu, Xiao-Mei; Chen, Tian-Jiao; Bai, Ming-Jie

    2016-01-01

    China is an urban and rural social model country. In the past three decades, the developing speed of rural areas has been much slower than urban areas, which may lead to the differences in dietary patterns. This study aimed to investigate the disparities of dietary structures from urban and rural children, and to analyze the effects of different dietary patterns on their adverse outcome. Among 1590 students, aged 11 years to 17 years, from primary and middle schools, a cross-sectional study was conducted. There were three dietary patterns recognized: Westernization structure, meat diet structure, and Western and Chinese structure. Compared with rural students, more urban students were in the highest categories of the whole dietary patterns (p < 0.001). Overweight/obesity and central adiposity were more prevailing among urban students, while rural students had a more prevailing risk of bone fracture (p < 0.05). Through the adjustment for all confounding factors, the Westernization structure could increase the risk of overweight/obesity and central adiposity, the meat structure could increase the risk of elevated blood pressure/hypertension, while the risk of low bone mineral quality could be reduced by the Chinese and Western structure. In conclusion, a rural-urban disparity in dietary patterns was found in our study, and different dietary patterns were associated with the risk of some adverse outcomes. Therefore, there were different prevalences of the adverse outcomes between rural and urban students. PMID:27608038

  18. Rural-Urban Differences of Dietary Patterns, Overweight, and Bone Mineral Status in Chinese Students.

    PubMed

    Yang, Yang; Hu, Xiao-Mei; Chen, Tian-Jiao; Bai, Ming-Jie

    2016-09-06

    China is an urban and rural social model country. In the past three decades, the developing speed of rural areas has been much slower than urban areas, which may lead to the differences in dietary patterns. This study aimed to investigate the disparities of dietary structures from urban and rural children, and to analyze the effects of different dietary patterns on their adverse outcome. Among 1590 students, aged 11 years to 17 years, from primary and middle schools, a cross-sectional study was conducted. There were three dietary patterns recognized: Westernization structure, meat diet structure, and Western and Chinese structure. Compared with rural students, more urban students were in the highest categories of the whole dietary patterns (p < 0.001). Overweight/obesity and central adiposity were more prevailing among urban students, while rural students had a more prevailing risk of bone fracture (p < 0.05). Through the adjustment for all confounding factors, the Westernization structure could increase the risk of overweight/obesity and central adiposity, the meat structure could increase the risk of elevated blood pressure/hypertension, while the risk of low bone mineral quality could be reduced by the Chinese and Western structure. In conclusion, a rural-urban disparity in dietary patterns was found in our study, and different dietary patterns were associated with the risk of some adverse outcomes. Therefore, there were different prevalences of the adverse outcomes between rural and urban students.

  19. Postnatal changes in the growth dynamics of the human face revealed from bone modelling patterns

    PubMed Central

    Martinez-Maza, Cayetana; Rosas, Antonio; Nieto-Díaz, Manuel

    2013-01-01

    Human skull morphology results from complex processes that involve the coordinated growth and interaction of its skeletal components to keep a functional and structural balance. Previous histological works have studied the growth of different craniofacial regions and their relationship to functional spaces in humans up to 14 years old. Nevertheless, how the growth dynamics of the facial skeleton and the mandible are related and how this relationship changes through the late ontogeny remain poorly understood. To approach these two questions, we have compared the bone modelling activities of the craniofacial skeleton from a sample of subadult and adult humans. In this study, we have established for the first time the bone modelling pattern of the face and the mandible from adult humans. Our analyses reveal a patchy distribution of the bone modelling fields (overemphasized by the presence of surface islands with no histological information) reflecting the complex growth dynamics associated to the individual morphology. Subadult and adult specimens show important differences in the bone modelling patterns of the anterior region of the facial skeleton and the posterior region of the mandible. These differences indicate developmental changes in the growth directions of the whole craniofacial complex, from a predominantly downward growth in subadults that turns to a forward growth observed in the adult craniofacial skeleton. We hypothesize that these ontogenetic changes would respond to the physiological and physical requirements to enlarge the oral and nasal cavities once maturation of the brain and the closure of the cranial sutures have taken place during craniofacial development. PMID:23819603

  20. Meteorin-Like Shows Unique Expression Pattern in Bone and Its Overexpression Inhibits Osteoblast Differentiation

    PubMed Central

    Gong, Weiyan; Liu, Yong; Wu, Zhihong; Wang, Shaohai; Qiu, Guixing; Lin, Shouqing

    2016-01-01

    The present study was performed to identify and characterize genes involved in osteoblasts function. Firstly, we constructed and sequenced a human osteoblast full-length cDNA library to screen for genes whose functions have not been reported and further identify these candidate genes through detecting the relationship with the activator protein-1 (AP-1) transcription factor complex using a dual luciferase reporter system. Only one gene, namely METRNL (Meteorin, glial cell differentiation regulator-like) has been screened out. We performed immunohistochemistry to analyze expression patterns in bone and established a stable transfection MG63 cell line of METRNL-EGFP fusion protein overexpression to analyze the function of METRNL in mineralized nodule formation. Immunohistochemistry showed METRNL expression in hypertrophic chondrocytes and osteoblasts lining trabecular bone surfaces. Overexpression of METRNL inhibited mineralized nodule formation by the MG63 osteosarcoma cell line. Thus, the identified gene, METRNL, which is associated with AP-1 transcription factor complex activity, has a unique expression pattern in bone. In addition, the anomalous expression of METRNL may inhibit bone cell differentiation. PMID:27716826

  1. Spatial and temporal patterns of bone formation in ectopically pre-fabricated, autologous cell-based engineered bone flaps in rabbits

    PubMed Central

    Scheufler, Oliver; Schaefer, Dirk J; Jaquiery, Claude; Braccini, Alessandra; Wendt, David J; Gasser, Jürg A; Galli, Raffaele; Pierer, Gerhard; Heberer, Michael; Martin, Ivan

    2008-01-01

    Biological substitutes for autologous bone flaps could be generated by combining flap pre-fabrication and bone tissue engineering concepts. Here, we investigated the pattern of neotissue formation within large pre-fabricated engineered bone flaps in rabbits. Bone marrow stromal cells from 12 New Zealand White rabbits were expanded and uniformly seeded in porous hydroxyapatite scaffolds (tapered cylinders, 10–20 mm diameter, 30 mm height) using a perfusion bioreactor. Autologous cell-scaffold constructs were wrapped in a panniculus carnosus flap, covered by a semipermeable membrane and ectopically implanted. Histological analysis, substantiated by magnetic resonance imaging (MRI) and micro-computerized tomography scans, indicated three distinct zones: an outer one, including bone tissue; a middle zone, formed by fibrous connective tissue; and a central zone, essentially necrotic. The depths of connective tissue and of bone ingrowth were consistent at different construct diameters and significantly increased from respectively 3.1 ± 0.7 mm and 1.0 ± 0.4 mm at 8 weeks to 3.7± 0.6 mm and 1.4 ± 0.6 mm at 12 weeks. Bone formation was found at a maximum depth of 1.8 mm after 12 weeks. Our findings indicate the feasibility of ectopic pre-fabrication of large cell-based engineered bone flaps and prompt for the implementation of strategies to improve construct vascularization, in order to possibly accelerate bone formation towards the core of the grafts. PMID:18782188

  2. International patterns of practice in radiotherapy for bone metastases: A review of the literature

    PubMed Central

    McDonald, Rachel; Chow, Edward; Lam, Henry; Rowbottom, Leigha; Soliman, Hany

    2014-01-01

    Purpose: Radiation therapy is the standard treatment for symptomatic bone metastases. Several randomized control trials and meta-analyses have concluded a similar efficacy in pain relief when comparing single versus multiple fraction regimes. However, there continues to be reluctance to conform to published guidelines that recommend a single treatment for the palliation of painful bone metastases. The purpose of this literature review is to summarize international patterns of practice, and to determine if guidelines recommending single fraction treatment have been implemented in clinical care. Methods: A literature search was conducted in Ovid Medline, Embase, and Cochrane Central. Search words included, ‘bone metastases’, ‘radiation therapy’, ‘radiotherapy’, ‘patterns of practice’, and ‘dose fractionation’. Both prospective and retrospective studies that investigated the prescription of radiotherapy to bone metastases using actual patient databases were included. Articles were excluded if they investigated hypothetical scenarios. Results: Six hundred and thirteen results were generated from the literature search. Twenty-six articles met the inclusion criteria. Of these, 11 were Canadian, 8 were European, 6 were American, and 1 was Australian. The use of single fraction radiotherapy (SFRT) ranged from 3% to 75%, but was generally lower in American studies. Choice of fractionation depended on a variety of factors, including patient age, prognosis, site of irradiation, and physician experience. Conclusion: Despite the publication of robust randomized control trials, meta-analyses, and clinical practice guidelines recommending the use of a single treatment to palliate uncomplicated bone metastasis, SFRT is internationally underutilized. PMID:26909305

  3. Strain measurement of a mouse bone by 3D-electronic speckle pattern interferometry (3D-ESPI)

    NASA Astrophysics Data System (ADS)

    Samala, Praveen R.; Su, Min; Liu, Sheng; Jiang, Hui H.; Yokota, Hiroki; Yang, Lianxiang

    2005-08-01

    Bone is a mechanosensitive tissue that adapts its mass, architecture and mechanical properties to mechanical loading. Appropriate mechanical loads provide an effective means to stimulate bone remodeling and prevent from bone loss. It is controversial whether in situ strain in bone is a critical determinant in enhancement of bone formation, and it is therefore important to evaluate load-driven strain in bone. Using electronic speckle pattern interferometry, we determined high-resolution three-dimensional strains on the mouse femur in response to two loading modalities: an axial loading modality (ALM) and a knee loading modality (KLM). We demonstrated that these two loading modalities induced a different pattern of strain distributions. ALM generated strain in the midshaft of cortical bone, while strains with KLM were concentrated on the distal epiphysis of the mouse femur. Since KLM is capable of enhancing bone formation in cortical bone distant from the knee, the current results indicate that in situ strain is not always necessary for load-driven bone formation.

  4. Bone

    NASA Astrophysics Data System (ADS)

    Helmberger, Thomas K.; Hoffmann, Ralf-Thorsten

    The typical clinical signs in bone tumours are pain, destruction and destabilization, immobilization, neurologic deficits, and finally functional impairment. Primary malignant bone tumours are a rare entity, accounting for about 0.2% of all malignancies. Also benign primary bone tumours are in total rare and mostly asymptomatic. The most common symptomatic benign bone tumour is osteoid osteoma with an incidence of 1:2000.

  5. Interpretation of hip fracture patterns using areal bone mineral density in the proximal femur.

    PubMed

    Hey, Hwee Weng Dennis; Sng, Weizhong Jonathan; Lim, Joel Louis Zongwei; Tan, Chuen Seng; Gan, Alfred Tau Liang; Ng, Jun Han Charles; Kagda, Fareed H Y

    2015-12-01

    Bone mineral density scans are currently interpreted based on an average score of the entire proximal femur. Improvements in technology now allow us to measure bone density in specific regions of the proximal femur. The study attempts to explain the pathophysiology of neck of femur (NOF) and intertrochanteric/basi-cervical (IT) fractures by correlating areal BMD (aBMD) scores with fracture patterns, and explore possible predictors for these fracture patterns. This is a single institution retrospective study on all patients who underwent hip surgeries from June 2010 to August 2012. A total of 106 patients (44 IT/basi-cervical, 62 NOF fractures) were studied. The data retrieved include patient characteristics and aBMD scores measured at different regions of the contralateral hip within 1 month of the injury. Demographic and clinical characteristic differences between IT and NOF fractures were analyzed using Fisher's Exact test and two-sample t test. Relationship between aBMD scores and fracture patterns was assessed using multivariable regression modeling. After adjusted multivariable analysis, T-Troc and T-inter scores were significantly lower in intertrochanteric/basi-cervical fractures compared to neck of femur fractures (P = 0.022 and P = 0.026, respectively). Both intertrochanteric/basi-cervical fractures (mean T.Tot -1.99) and neck of femur fractures (mean T.Tot -1.64) were not found to be associated with a mean T.tot less than -2.5. However, the mean aBMD scores were consistently less than -2.5 for both intertrochanteric/basi-cervical fractures and neck of femur fractures. Gender and calcium intake at the time of injury were associated with specific hip fracture patterns (P = 0.002 and P = 0.011, respectively). Hip fracture patterns following low energy trauma may be influenced by the pattern of reduced bone density in different areas of the hip. Intertrochanteric/basi-cervical fractures were associated with significantly lower T-Troc and T-Inter scores

  6. Use of electronic speckle pattern interferometry to study the biomechanics of human bone and prostheses

    NASA Astrophysics Data System (ADS)

    Heras-Palov, Carlos; Tyrer, John R.; Petzing, Jon N.; Stoyle, Tom F.; Gregg, P. J.

    1995-02-01

    Electronic speckle pattern interferometry (ESPI) is a laser based technique developed for the study of stresses and strains in complex structures. This method consists of the projection of two laser beams onto the object of study. This produces a visible pattern that is recorded by a video camera. When the structure is stressed in a jig, the pattern changes depending on the in- plane and out-of-plane deformation and movement of the surface observed. This allows us to qualify and quantify strain in the whole area under study, in real time. We describe the method of application of ESPI to the study of the biomechanics of the proximal femur, before and after the implantation of the femoral component of a total hip replacement in cadaveric femora, under physiological loads and tensions, and report our preliminary results. The information obtained with this technique should provide a better understanding of the biomechanics of bone after joint replacement.

  7. Patterns of Care Among Patients Receiving Radiation Therapy for Bone Metastases at a Large Academic Institution

    SciTech Connect

    Ellsworth, Susannah G.; Alcorn, Sara R.; Hales, Russell K.; McNutt, Todd R.; DeWeese, Theodore L.; Smith, Thomas J.

    2014-08-01

    Purpose: This study evaluates outcomes and patterns of care among patients receiving radiation therapy (RT) for bone metastases at a high-volume academic institution. Methods and Materials: Records of all patients whose final RT course was for bone metastases from April 2007 to July 2012 were identified from electronic medical records. Chart review yielded demographic and clinical data. Rates of complicated versus uncomplicated bone metastases were not analyzed. Results: We identified 339 patients whose final RT course was for bone metastases. Of these, 52.2% were male; median age was 65 years old. The most common primary was non-small-cell lung cancer (29%). Most patients (83%) were prescribed ≤10 fractions; 8% received single-fraction RT. Most patients (52%) had a documented goals of care (GOC) discussion with their radiation oncologist; hospice referral rates were higher when patients had such discussions (66% with vs 50% without GOC discussion, P=.004). Median life expectancy after RT was 96 days. Median survival after RT was shorter based on inpatient as opposed to outpatient status at the time of consultation (35 vs 136 days, respectively, P<.001). Hospice referrals occurred for 56% of patients, with a median interval between completion of RT and hospice referral of 29 days and a median hospice stay of 22 days. Conclusions: These data document excellent adherence to American Society for Radiation Oncolology Choosing Wisely recommendation to avoid routinely using >10 fractions of palliative RT for bone metastasis. Nonetheless, single-fraction RT remains relatively uncommon. Participating in GOC discussions with a radiation oncologist is associated with higher rates of hospice referral. Inpatient status at consultation is associated with short survival.

  8. Camurati-Engelmann disease in a family from Croatian Island: an old bone scan confirmed pattern of inheritance.

    PubMed

    Baretić, Maja; Korsić, Mirko; Potocki, Kristina; Horvatić, Gordana Herceg; Orlić, Zeljka Crncević

    2014-06-01

    34-year old patient had history of muscular wasting, easy fatigability, pain in extremities and waddling gait since age of four. During the time, neuromuscular disease was suspected, but not confirmed. Elevated bone alkaline phosphatase as well as other bone turnover markers (osteocalcin, procollagen, telopeptide) indicated further skeletal evaluation. Symmetrical enhanced uptake on technetium methylene diphosphonate [99mTc]MPD bone scintigraphy at diaphyses of longitudinal bones and scull matched cortical thickening of long bones and sclerosis of the scull seen at radiograms. Those findings pointed to Camurati-Engelmann disease misdiagnosed for the long time. This rare genetic autosomal dominant disorder was retrospectively diagnosed in asymptomatic father too on the basis of bone scans done long time ago. Old family member scans confirmed heredity pattern of the disease.

  9. Dietary patterns explaining differences in bone mineral density and hip structure in the elderly: the Rotterdam Study.

    PubMed

    de Jonge, Ester Al; Kiefte-de Jong, Jessica C; Hofman, Albert; Uitterlinden, André G; Kieboom, Brenda Ct; Voortman, Trudy; Franco, Oscar H; Rivadeneira, Fernando

    2017-01-01

    Evidence on the association between dietary patterns, measures of hip bone geometry, and subsequent fracture risk are scarce. The objective of this study was to evaluate whether dietary patterns that explain most variation in bone mineral density (BMD) and hip bone geometry are associated with fracture risk. We included 4028 subjects aged ≥55 y from the Rotterdam study. Intake of 28 food groups was assessed with the use of food-frequency questionnaires. BMD, bone width, section modulus (SM; reflecting bending strength) and cortical buckling ratio (BR; reflecting bone instability) were measured with the use of dual-energy X-ray absorptiometry. BMD and geometry-specific dietary patterns were identified with the use of reduced rank regression. Fracture data were reported by general practitioners (median follow-up 14.8 y). We identified 4 dietary patterns. Of the 4, we named 2 patterns "fruit, vegetables, and dairy" and "sweets, animal fat, and low meat," respectively. These 2 patterns were used for further analysis. Independently of confounders, adherence to the fruit, vegetables, and dairy pattern was associated with high BMD, high SM, low BR, and low risk of fractures [HR (95% CI) for osteoporotic fractures: 0.90 (0.83, 0.96); for hip fractures: 0.85 (0.81, 0.89) per z score of dietary pattern adherence]. Adherence to the sweets, animal fat, and low meat pattern was associated with high bone width, high SM, high BR, and high risk of fractures [HR (95% CI) for osteoporotic fractures: 1.08 (1.00, 1.06); for hip fractures: 1.06 (1.02, 1.12) per z score]. The fruit, vegetables, and dairy pattern might be associated with lower fracture risk because of high BMD, high bending strength, and more stable bones. The sweets, animal fat, and low meat pattern might be associated with higher fracture risk because of widened, unstable bones, independently of BMD. Dietary recommendations associated with bone geometry in addition to BMD might influence risk of fractures. © 2017

  10. Region-dependent patterns of trabecular bone growth in the human proximal femur: A study of 3D bone microarchitecture from early postnatal to late childhood period.

    PubMed

    Milovanovic, Petar; Djonic, Danijela; Hahn, Michael; Amling, Michael; Busse, Björn; Djuric, Marija

    2017-10-01

    Parallel with body growth and development, bone structure in non-adults is reorganized to achieve the particular design observed in mature individuals. We traced the changes in three-dimensional trabecular microarchitectural design during the phases of locomotor maturation to clarify how human bone adapts to mechanical demands. Micro-CT was performed on biomechanically-relevant subregions of the proximal femur (medial, intermediate and lateral neck regions, intertrochanteric region, metaphyseal region) from early postnatal period to late childhood. Developmental patterns of trabecular microarchitecture showed that gestationally overproduced bone present at birth underwent the most dramatic reduction during the first year, followed by a reversing trend in some of the quantitative parameters (e.g., bone volume fraction, trabecular anisotropy). Certain regional anisotropy already present at birth is further accentuated into the childhood suggesting an adaptation to differential loading environments. Trabecular eccentricity in the femoral neck was particularly accentuated during childhood, giving the medial neck-the site mostly loaded in walking-superior microarchitectural design (high bone volume fraction and anisotropy, the earliest appearance and predominance of plate- and honeycomb-shaped trabeculae). While providing quantitative data on how bone microarchitecture adapts to increasing mechanical demands occurring during the phases of locomotor maturation, the study reveals how regional anisotropy develops in the proximal femur to ensure a functional and competent bone structure. Decomposing the region-specific patterns of bone mass accrual is important in understanding skeletal adaptations to bipedalism, as well for understanding why fractures often occur location-dependent, both in pediatric and elderly individuals. © 2017 Wiley Periodicals, Inc.

  11. Semaphorin III is needed for normal patterning and growth of nerves, bones and heart.

    PubMed

    Behar, O; Golden, J A; Mashimo, H; Schoen, F J; Fishman, M C

    1996-10-10

    The expression patterns of the recently discovered family of semaphorin genes suggests that they have widespread roles in embryonic development. Some seem to guide neuronal growth cones, but otherwise their functions are unknown. Semaphorin III is a membrane-associated secreted protein with a developmentally dynamic pattern of expression, including particular domains of the nervous system, the borders of developing bones, and the heart. In vitro, semaphorin III causes growth-cone collapse, and repels cutaneous sensory axons from the ventral spinal cord. Mutants in the Drosophila gene semaII, which encodes a related semaphorin, die after eclosion, but no responsible abnormality is evident. We have generated mice mutant in the semaIII gene by homologous recombination. Here we show that in the mutants, some sensory axons project into inappropriate regions of the spinal cord where semaIII is normally expressed. The cerebral cortex of homozygous mutant mice shows a paucity of neuropil and abnormally oriented neuronal processes, especially of the large pyramidal neurons. Certain embryonic bones and cartilaginous structures develop abnormally, with vertebral fusions and partial rib duplications. The few mice that survive more than a few days postnatally manifest pronounced and selective hypertrophy of the right ventricle of the heart and dilation of the right atrium. Thus, semaphorin III might serve as a signal that restrains growth in several developing organs.

  12. Cricket fast bowling workload patterns as risk factors for tendon, muscle, bone and joint injuries.

    PubMed

    Orchard, John W; Blanch, Peter; Paoloni, Justin; Kountouris, Alex; Sims, Kevin; Orchard, Jessica J; Brukner, Peter

    2015-08-01

    To assess workload-related risk factors for injuries to particular tissue types in cricket fast bowlers. 235 fast bowlers who bowled in 14600 player innings over a period of 15 years were followed in a prospective cohort risk factor study to compare overs bowled in each match (including preceding workload patterns) and injury risk in the 3-4 weeks subsequent to the match. Injuries were categorised according to the affected tissue type as either: bone stress, tendon injuries, muscle strain or joint injuries. Workload risk factors were examined using binomial logistic regression multivariate analysis, with a forward stepwise procedure requiring a significance of <0.05. High acute match workload and high previous season workload were risk factors for tendon injuries, but high medium term (3-month workload) was protective. For bone stress injuries, high medium term workload and low career workload were risk factors. For joint injuries, high previous season and career workload were risk factors. There was little relationship between muscle injury and workload although high previous season workload was slightly protective. The level of injury risk for some tissue types varies in response to preceding fast bowling workload, with tendon injuries most affected by workload patterns. Workload planning may need to be individualised, depending on individual susceptibility to various injury types. This study supports the theory that tendons are at lowest risk with consistent workloads and susceptible to injury with sudden upgrades in workload. Gradual upgrades are recommended, particularly at the start of a bowler's career to reduce the risk of bone stress injury. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  13. Bone ridge patterning during musculoskeletal assembly is mediated through SCX regulation of Bmp4 at the tendon-skeleton junction

    PubMed Central

    Blitz, Einat; Viukov, Sergey; Sharir, Amnon; Shwartz, Yulia; Galloway, Jenna L.; Price, Brian A.; Johnson, Randy L.; Tabin, Clifford J.; Schweitzer, Ronen; Zelzer, Elazar

    2011-01-01

    SUMMARY During the assembly of the musculoskeletal system, bone ridges provide a stable anchoring point and stress dissipation for the attachment of muscles via tendons to the skeleton. In this study, we investigate the development of the deltoid tuberosity as a model for bone ridge formation. We show that the deltoid tuberosity develops through endochondral ossification in a two-phase process: Initiation is regulated by a signal from the tendons, whereas the subsequent growth phase is muscle-dependent. We then show that the transcription factor scleraxis (SCX) regulates Bmp4 in tendon cells at their insertion site. The inhibition of deltoid tuberosity formation and several other bone ridges in embryos in which Bmp4 expression was blocked specifically in Scx-expressing cells implicates BMP4 as a key mediator of tendon effects on bone ridge formation. This study establishes a mechanistic basis for tendon-skeleton regulatory interactions during musculoskeletal assembly and bone secondary patterning. PMID:20059955

  14. Speckle shearing pattern interferometry to assess mechanical strain in the human mandible jaw bone under physiological stress

    NASA Astrophysics Data System (ADS)

    Moreno, V.; Vázquez-Vázquez, C.; Gallas, M.; Crespo, J.

    2011-05-01

    Electronic Speckle Pattern Interferometry (ESPI) has been used in experiments to measure displacement on the surface of bones undergoing external forces. However in order to asses directly the derivative of the displacements a related technique, Shearography, is used. This technique has been applied in biomechanical experiments although limited to small pieces of bone to determine their elastic properties. In this work we propose the use of Shearing Speckle Interferometry to evaluate the mechanical behaviour of the human mandible under compressive stress, simulating masticatory forces or impacts, in order to analyze the strain distribution on mandibular bone.

  15. Associations of Baltic Sea and Mediterranean dietary patterns with bone mineral density in elderly women.

    PubMed

    Erkkilä, Arja T; Sadeghi, Homa; Isanejad, Masoud; Mursu, Jaakko; Tuppurainen, Marjo; Kröger, Heikki

    2017-10-01

    Dietary quality in relation to bone health has been analysed in relatively few studies. The current study aimed to assess the association of the Baltic Sea diet (BSD) and the Mediterranean diet (MD) with bone mineral density (BMD) among elderly women. Lumbar, femoral and total body BMD were measured by dual-energy X-ray absorptiometry at baseline and year 3. Dietary intake was measured by 3 d food record at baseline. BSD and MD scores were calculated from food and alcohol consumption and nutrient intake. Information on lifestyle, diseases and medications was collected by questionnaires. Longitudinal associations of BSD and MD scores with BMD were analysed using linear mixed models. Interventional prospective Kuopio Osteoporosis Risk Factor and Fracture Prevention study including women aged 65-71 years and residing in Kuopio province, Finland. Women (n 554) with mean age of 67·9 (sd 1·9) years and mean BMI of 28·8 (sd 4·7) kg/m2. Higher BSD scores were associated with higher intakes of fruit and berries, vegetables, fish and low-fat dairy products, and lower intake of sausage. Higher MD scores were associated with higher consumption of fruit and berries and vegetables. BSD and MD scores were associated with higher PUFA:SFA and higher fibre intake. Femoral, lumbar or total body BMD was not significantly different among the quartiles of BSD or MD score. The lack of associations suggest that Baltic Sea and Mediterranean dietary patterns may not adequately reflect dietary factors relevant to bone health.

  16. Effectiveness of Bone Marrow Stromal Cell Sheets in Maintaining Random-Pattern Skin Flaps in an Experimental Animal Model.

    PubMed

    Kira, Tsutomu; Omokawa, Shohei; Akahane, Manabu; Shimizu, Takamasa; Nakano, Kenichi; Nakanishi, Yasuaki; Onishi, Tadanobu; Kido, Akira; Inagaki, Yusuke; Tanaka, Yasuhito

    2015-11-01

    Bone marrow stromal cells can be applied therapeutically to enhance angiogenesis; however, the use of bone marrow stromal cell suspensions reduces efficiency because of low-level attachment. The authors hypothesized that bone marrow stromal cell sheets would facilitate cell fixation, thus enhancing angiogenesis. The authors investigated flap survival area and enhancement of angiogenic factors in a rat random-pattern skin flap model after application of bone marrow stromal cell sheets. Bone marrow stromal cell sheets (prepared from 7-week-old rat femurs) were cultured under four different hypoxic conditions. Sheets with the highest angiogenic potential, determined by an in vitro pilot study, were injected into subcutaneous layers of the rat dorsum (bone marrow stromal cell sheet group). A control group (phosphate-buffered saline only) was included. On day 2 after injection, caudally based random-pattern skin flaps (12 × 3 cm) were elevated. On day 7 after elevation, surviving skin flap areas were measured. Skin samples were harvested from each flap and gene expression levels of vascular endothelial growth factor and basic fibroblast growth factor were measured by quantitative real-time polymerase chain reaction. Skin flap survival area (71.6 ± 2.3 percent versus 51.5 ± 3.3 percent) and levels of vascular endothelial growth factor and basic fibroblast growth factor were significantly higher in the bone marrow stromal cell sheet group than in the control group (p < 0.05). Implantation of bone marrow stromal cell sheets increased the survival area of random-pattern skin flaps. Expression of angiogenic factors may have contributed to the increased flap survival.

  17. The remodeling pattern of human mandibular alveolar bone during prenatal formation from 19 to 270mm CRL.

    PubMed

    Radlanski, Ralf J; Renz, Herbert; Tsengelsaikhan, Nyamdorj; Schuster, Felix; Zimmermann, Camilla A

    2016-05-01

    The underlying mechanisms of human bone morphogenesis leading to a topologically specific shape remain unknown, despite increasing knowledge of the basic molecular aspects of bone formation and its regulation. The formation of the alveolar bone, which houses the dental primordia, and later the dental roots, may serve as a model to approach general questions of bone formation. Twenty-five heads of human embryos and fetuses (Radlanski-Collection, Berlin) ranging from 19mm to 270mm (crown-rump-length) CRL were prepared as histological serial sections. For each stage, virtual 3D-reconstructions were made in order to study the morphogenesis of the mandibular molar primordia with their surrounding bone. Special focus was given to recording the bone-remodeling pattern, as diagnosed from the histological sections. In early stages (19-31mm CRL) developing bone was characterized by appositional only. At 41, in the canine region, mm CRL bony extensions were found forming on the bottom of the trough. Besides general apposition, regions with resting surfaces were also found. At a fetal size of 53mm CRL, septa have developed and led to a compartment for canine development. Furthermore, one shared compartment for the incisor primordia and another shared compartment for the molars also developed. Moreover, the inner surfaces of the dental crypts showed resorption of bone. From this stage on, a general pattern became established such that the compartmentalizing ridges and septa between all of the dental primordia and the brims of the crypts were noted, and were due to appositional growth of bone, while the crypts enlarged on their inner surfaces by resorption. By 160mm CRL, the dental primordia were larger, and all of the bony septa had become reduced in size. The primordia for the permanent teeth became visible at 225mm CRL and shared the crypts of their corresponding deciduous primordia.

  18. Microscopic Pattern of Bone Fractures as an Indicator of Blast Trauma: A Pilot Study.

    PubMed

    Pechníková, Marketa; Mazzarelli, Debora; Poppa, Pasquale; Gibelli, Daniele; Scossa Baggi, Emilio; Cattaneo, Cristina

    2015-09-01

    The assessment of fractures is a key issue in forensic anthropology; however, very few studies deal with the features of fractures due to explosion in comparison with other traumatic injuries. This study focuses on fractures resulting from blast trauma and two types of blunt force trauma (manual compression and running over), applied to corpses of pigs; 163 osteons were examined within forty fractures by the transmission light microscopy. Blast lesions showed a higher percentage of fracture lines through the Haversian canal, whereas in other types of trauma, the fractures went across the inner lamellae. Significant differences between samples hit by blast energy and those runover or manually compressed were observed (p<0.05). The frequency of pattern A is significantly higher in exploded bones than in runover and compressed. Microscopic analysis of the fracture line may provide information about the type of trauma, especially for what concerns blast trauma.

  19. The topologic and chronologic patterns of hematopoietic cell seeding in host femoral bone marrow after transplantation.

    PubMed

    Askenasy, Nadir; Stein, Jeremiah; Yaniv, Isaac; Farkas, Daniel L

    2003-08-01

    The early stages of homing, seeding, and engraftment of hematopoietic stem and progenitor cells are poorly characterized. We have developed an optical technique that allows in vivo tracking of transplanted, fluorescent-tagged cells in the host femurs. In this study we used fluorescence microscopy to monitor the topologic and chronologic patterns of hematopoietic cell seeding in the femoral bone marrow (BM) of mice. PKH-labeled cells homed to the femur within minutes after injection into a peripheral vein. Most cells drifted within the marrow space and gradually seeded in clusters close to the endosteal surface of the epiphyseal cortex. Three days after transplantation 85% to 94% (14%) of PKH-labeled cells in the femoral marrow were located within 100 microm of the epiphyseal bone surface (P <.001 versus the more central cells), whereas labeled cells were absent in the femoral diaphysis. Primary seeding of juxtaendosteal, epiphyseal marrow occurred independently of recipient conditioning (myeloablated and nonconditioned hosts), donor-recipient antigen disparity, or the phenotype of the injected cells (whole BM and lineage-negative cells) and was consistently observed in secondary recipients of BM-homed cells. Seeding in regions close to the epiphyseal bone was also observed in freshly excised femurs perfused ex vivo and in femurs assessed without prior placement of optical windows, indicating that the site of primary seeding was not affected by surgical placement of optical windows. Four to 5 days after transplantation, cellular clusters appeared in the more central regions of the epiphyses and in the diaphyses. Centrally located cells showed decreased PKH fluorescence, suggesting that they were progeny of the seeding cells, and brightly fluorescent cells (quiescent first-generation seeding cells) were observed close to the bone surface for as long as 24 days after transplantation. These data indicate that the periphery of the femoral marrow hosts primary seeding

  20. Association between Dietary Patterns of Meat and Fish Consumption with Bone Mineral Density or Fracture Risk: A Systematic Literature

    PubMed Central

    Avanzato, Ilaria; Nichetti, Mara; D’Antona, Giuseppe

    2017-01-01

    This systematic review aimed to investigate the association of fish and sea fish dietary patterns (FishDiet) and meat or processed meat dietary patterns (MeatDiet) with bone mineral density (BMD) and/or risk of fractures (RF). This review includes 37 studies with a total of 432,924 subjects. The results suggest that MeatDiet and FishDiet did not affect BMD or RF in 48.2% of the subjects with MeatDiet and in 86.5% of the subjects with FishDiet. Positive effects on bone were found in 3% of subjects with MeatDiet and in 12% with FishDiet. Negative effects on bone were observed in 2.7% of FishDiet and in 47.9% of MeatDiet. Major negative effects of MeatDiet were found in subjects located in the Netherlands, Greece, Germany, Italy, Norway, UK and Spain who do not sustain a Mediterranean diet (92.7%); in Korea (27.1%); in Brazil and Mexico (96.4%); and in Australia (62.5%). This study suggests that protein intake from fish or meat is not harmful to bone. Negative effects on bone linked to FishDiet are almost null. Negative effects on bone were associated to MeatDiet in the setting of a Western Diet but not in Mediterranean or Asian Diets.

  1. Patterns in the bony skull development of marsupials: high variation in onset of ossification and conserved regions of bone contact

    PubMed Central

    Spiekman, Stephan N. F.; Werneburg, Ingmar

    2017-01-01

    Development in marsupials is specialized towards an extremely short gestation and highly altricial newborns. As a result, marsupial neonates display morphological adaptations at birth related to functional constraints. However, little is known about the variability of marsupial skull development and its relation to morphological diversity. We studied bony skull development in five marsupial species. The relative timing of the onset of ossification was compared to literature data and the ossification sequence of the marsupial ancestor was reconstructed using squared-change parsimony. The high range of variation in the onset of ossification meant that no patterns could be observed that differentiate species. This finding challenges traditional studies concentrating on the onset of ossification as a marker for phylogeny or as a functional proxy. Our study presents observations on the developmental timing of cranial bone-to-bone contacts and their evolutionary implications. Although certain bone contacts display high levels of variation, connections of early and late development are quite conserved and informative. Bones that surround the oral cavity are generally the first to connect and the bones of the occipital region are among the last. We conclude that bone contact is preferable over onset of ossification for studying cranial bone development. PMID:28233826

  2. Fetal and childhood growth patterns associated with bone mass in school-age children: the Generation R Study.

    PubMed

    Heppe, Denise Hm; Medina-Gomez, Carolina; de Jongste, Johan C; Raat, Hein; Steegers, Eric Ap; Hofman, Albert; Rivadeneira, Fernando; Jaddoe, Vincent Wv

    2014-12-01

    Low birth weight is associated with lower bone accrual in children and peak bone mass in adults. We assessed how different patterns of longitudinal fetal and early childhood growth influence bone properties at school age. In 5431 children participating in a population-based prospective cohort study, we measured fetal growth by ultrasound at 20 and 30 weeks gestation, and childhood growth at birth, 1, 2, 3, and 4 years of age. We analyzed these growth measurements in relation to total body (less head) BMD measured by DXA at age 6. We used conditional growth modeling; a technique which takes into account correlation between repeatedly measured growth measures. Our results showed that estimated fetal weight gain, femur length growth between 20 and 30 weeks of gestation, femur length growth between 30 weeks and birth, as well as all height and weight growth measurements from birth to 4 years of age were all positively associated with BMC, bone area (BA), and BMD (all p < 0.01). Fetal femur length growth between 30 weeks and birth was positively associated with BMC and BA (both p < 0.001), but not with BMD. Overall, childhood growth measurements exerted a larger influence on bone measures than fetal growth measures. The strongest effect estimate was observed during the first year of life. Children born small (<10th percentile) for gestational age (SGA) had lower BMC and BA, but not BMD, than children born appropriate for gestational age (AGA), whereas children born large (>90th percentile) for gestational age (LGA) had higher BMC and BA (all p < 0.001). These differences were no longer present in children showing subsequent accelerated and decelerated infant growth, respectively. We conclude that both fetal and childhood growth patterns are associated with bone mineral accrual, showing the strongest effect estimates in infancy. Compensatory infant growth counteracts the adverse consequences of fetal growth restriction on bone development. © 2014 American

  3. Bare strange quark stars: formation and emission

    NASA Astrophysics Data System (ADS)

    Xu, Renxin

    Recent achievements of bare strange stars are briefly reviewed. A nascent protostrange star should be bare because of strong mass ejection and high temperature after the supernova detonation flame, and a crust can also hardly form except for a super-Eddington accretion. The magnetosphere of a bare strange star is composed mainly of e± pair plasma, where both inner and outer vacuum gaps work for radio as well as high energy nonthermal emission. A featureless thermal spectrum is expected since no ion is above the quark surface, whilst electron cyclotron lines could appear in some bare strange stars with suitable magnetic fields. Various astrophysical implications of bare strange stars are discussed.

  4. Patterns of Practice of Palliative Radiotherapy in Africa, Part 1: Bone and Brain Metastases

    SciTech Connect

    Sharma, Vinay Gaye, Papa Macoumba M.Med.; Wahab, Sherif Abdel; Ndlovu, Ntokozo; Ngoma, Twalib; Vanderpuye, Verna; Sowunmi, Anthonia; Kigula-Mugambe, Joseph; Jeremic, Branislav

    2008-03-15

    Purpose: To provide data on the pattern of practice of palliative radiotherapy (RT) on the African continent. Methods and Materials: A questionnaire was distributed to participants in a regional training course of the International Atomic Energy Agency in palliative cancer care and sent by e-mail to other institutions in Africa. Requested information included both infrastructure and human resources available and the pattern of RT practice for metastatic and locally advanced cancers. Results: Of 35 centers contacted, 24 (68%) completed the questionnaire. Although RT is used by most centers for most metastatic cancers, liver and lung metastases are treated with chemotherapy. Of 23 centers, 14 (61%) had a single RT regimen as an institutional policy for treating painful bone metastases, but only 5 centers (23%) of 23 used 8 Gy in 1 fraction. Brain metastases were being treated by RT to the whole brain to 30 Gy in 10 fractions, either exclusively (n = 13, 56%) or in addition to the use of 20 Gy in 5 fractions (n = 3, 14%). Conclusion: Radiotherapy is a major component of treatment of cancer patients in African countries. There is consensus among few centers for treatment schedules for almost all sites regarding time and dose-fractionation characteristics of RT regimens used and/or indications for the use of RT in this setting.

  5. A systematic examination of the bone destruction pattern of the two-shot technique

    PubMed Central

    Stoetzer, Marcus; Stoetzer, Carsten; Rana, Majeed; Zeller, Alexander; Hanke, Alexander; Gellrich, Nils-Claudius; von See, Constantin

    2014-01-01

    Introduction: The two-shot technique is an effective stopping power method. The precise mechanisms of action on the bone and soft-tissue structures of the skull; however, remain largely unclear. The aim of this study is to compare the terminal ballistics of the two-shot and single-shot techniques. Materials and Methods: 40 fresh pigs’ heads were randomly divided into 4 groups (n = 10). Either a single shot or two shots were fired at each head with a full metal jacket or a semi-jacketed bullet. Using thin-layer computed tomography and photography, the diameter of the destruction pattern and the fractures along the bullet path were then imaged and assessed. Results: A single shot fired with a full metal jacket bullet causes minor lateral destruction along the bullet path. With two shots fired with a full metal jacket bullet, however, the maximum diameter of the bullet path is significantly greater (P < 0.05) than it is with a single shot fired with a full metal jacket bullet. In contrast, the maximum diameter with a semi-jacketed bullet is similar with the single-shot and two-shot techniques. Conclusion: With the two-shot technique, a full metal jacket bullet causes a destruction pattern that is comparable to that of a single shot fired with a semi-jacketed bullet. PMID:24812454

  6. 'Universal' microstructural patterns in cortical and trabecular, extracellular and extravascular bone materials: micromechanics-based prediction of anisotropic elasticity.

    PubMed

    Fritsch, Andreas; Hellmich, Christian

    2007-02-21

    Bone materials are characterized by an astonishing variability and diversity. Still, because of 'architectural constraints' due to once chosen material constituents and their physical interaction, the fundamental hierarchical organization or basic building plans of bone materials remain largely unchanged during biological evolution. Such universal patterns of microstructural organization govern the mechanical interaction of the elementary components of bone (hydroxyapatite, collagen, water; with directly measurable tissue-independent elastic properties), which are here quantified through a multiscale homogenization scheme delivering effective elastic properties of bone materials: at a scale of 10nm, long cylindrical collagen molecules, attached to each other at their ends by approximately 1.5nm long crosslinks and hosting intermolecular water inbetween, form a contiguous matrix called wet collagen. At a scale of several hundred nanometers, wet collagen and mineral crystal agglomerations interpenetrate each other, forming the mineralized fibril. At a scale of 5-10microm, the extracellular solid bone matrix is represented as collagen fibril inclusions embedded in a foam of largely disordered (extrafibrillar) mineral crystals. At a scale above the ultrastructure, where lacunae are embedded in extracellular bone matrix, the extravascular bone material is observed. Model estimates predicted from tissue-specific composition data gained from a multitude of chemical and physical tests agree remarkably well with corresponding acoustic stiffness experiments across a variety of cortical and trabecular, extracellular and extravascular materials. Besides from reconciling the well-documented, seemingly opposed concepts of 'mineral-reinforced collagen matrix' and 'collagen-reinforced mineral matrix' for bone ultrastructure, this approach opens new possibilities in the exploitation of computer tomographic data for nano-to-macro mechanics of bone organs.

  7. International Patterns of Practice in Palliative Radiotherapy for Painful Bone Metastases: Evidence-Based Practice?

    SciTech Connect

    Fairchild, Alysa; Barnes, Elizabeth; Ghosh, Sunita; Ben-Josef, Edgar; Roos, Daniel; Hartsell, William; Holt, Tanya; Wu, Jackson; Janjan, Nora; Chow, Edward

    2009-12-01

    Purpose: Multiple randomized controlled trials have demonstrated the equivalence of multifraction and single-fraction (SF) radiotherapy for the palliation of painful bone metastases (BM). However, according to previous surveys, SF schedules remain underused. The objectives of this study were to determine the current patterns of practice internationally and to investigate the factors influencing this practice. Methods and Materials: The members of three global radiation oncology professional organizations (American Society for Radiology Oncology [ASTRO], Canadian Association of Radiation Oncology [CARO], Royal Australian and New Zealand College of Radiologists) completed an Internet-based survey. The respondents described what radiotherapy dose fractionation they would recommend for 5 hypothetical cases describing patients with single or multiple painful BMs from breast, lung, or prostate cancer. Radiation oncologists rated the importance of patient, tumor, institution, and treatment factors, and descriptive statistics were compiled. The chi-square test was used for categorical variables and the Student t test for continuous variables. Logistic regression analysis identified predictors of the use of SF radiotherapy. Results: A total of 962 respondents, three-quarters ASTRO members, described 101 different dose schedules in common use (range, 3 Gy/1 fraction to 60 Gy/20 fractions). The median dose overall was 30 Gy/10 fractions. SF schedules were used the least often by ASTRO members practicing in the United States and most often by CARO members. Case, membership affiliation, country of training, location of practice, and practice type were independently predictive of the use of SF. The principal factors considered when prescribing were prognosis, risk of spinal cord compression, and performance status. Conclusion: Despite abundant evidence, most radiation oncologists continue to prescribe multifraction schedules for patients who fit the eligibility criteria of

  8. Characterizing felid tooth marking and gross bone damage patterns using GIS image analysis: an experimental feeding study with large felids.

    PubMed

    Parkinson, Jennifer A; Plummer, Thomas; Hartstone-Rose, Adam

    2015-03-01

    In recent years there has been much disagreement over the nature of carnivore involvement in Early Pleistocene zooarchaeological assemblages. This partially reflects the lack of reliable ways to identify the taphonomic signatures of different large carnivore taxa. It is often unclear which carnivore taxon or taxa may have played a role in forming or modifying faunal assemblages found associated with stone tools, and this lack of clarity impacts reconstructions of hominin behavior. The mode, frequency and nutritional yield of carcasses acquired by hominins, and the extent to which hominin foraging impinged on or was constrained by the guild of large predators are topics of great importance. This paper characterizes the taphonomic signature of large felids using a Geographic Information Systems (GIS) image analysis method to study tooth marking and gross bone damage on neotaphonomic experiments carried out with tigers (Panthera tigris) and African lions (Panthera leo) at the Carolina Tiger Rescue (Pittsboro, North Carolina). This sample of over 400 bones significantly increases the size of current neotaphonomic samples modeling felid feeding traces, more than doubling the number of felid-modified specimens described in the literature. We identify a typical pattern of bone damage resulting from large felid carcass modification, which can be distinguished from bone damage patterns produced by hyaenids and canids. In summary, this pattern consists of tooth marking largely restricted to limb bone ends and minimal bone fragmentation. The frequency of tooth marking imparted by large felids in this study is lower than that produced by hyaenids, while canid tooth mark frequencies fall between the two. Investigation of the FLK Zinj assemblage from Olduvai Gorge, Tanzania, has documented several specimens with surface damage similar to our neotaphonomic sample. This may signal early access to carcasses through 'power scavenging' by hominins. Copyright © 2014 Elsevier Ltd. All

  9. A survey of patterns of practice on palliative radiation therapy for bone metastasis in Korea.

    PubMed

    Chung, Yoonsun; Koom, Woong Sub; Ahn, Yong Chan; Park, Hee-Chul; Kim, Hak Jae; Yoon, Sang Min; Shin, Sangjin; Lee, Yoon Jae

    2013-12-01

    The aim of this study was to understand the practice patterns of palliative radiation therapy for bone metastasis in Korea among Korean radiation oncologists by survey and to determine the decision factors affecting the prescription of radiation therapy fractionation schedules. An Internet-based survey was performed from October 5 to October 23, 2009, among 177 active full members of the Korean Society for Radiation and Oncology (KOSRO). The survey questionnaire included general information about the respondent, three types of clinical scenario, depending on the life expectancy of the patients, and the decision factors that affected the prescription of a radiation therapy schedule. The most prescribed schedule was 30 Gy in 10 fractions regardless of the life expectancy of the patient. Also, it was found that a single fraction was seldom prescribed routinely in Korea. An increasing number prescribed fewer than 10 fractions as the life expectancy shortened; however, the prescription rate of a single fraction was still low. The general performance (and/or accompanying diseases) of patients and the life expectancy were the most considered factors in deciding the prescription of radiation therapy. Despite the abundant evidence supporting the equivalence of single- and multi-fraction radiation therapy, still, most Korean radiation oncologists continue to prescribe multi-fraction schedules depending on the general performance and life expectancy of the patients. Thus, we confirmed that there was a gap between evidence and practice, and treatment prescriptions can be strongly affected by decision factors other than published literature results.

  10. Bone morphogenetic proteins, eye patterning, and retinocollicular map formation in the mouse

    PubMed Central

    Plas, Daniel T.; Dhande, Onkar; Lopez, Joshua E.; Murali, Deepa; Thaller, Christina; Henkemeyer, Mark; Furuta, Yasuhide; Overbeek, Paul; Crair, Michael C.

    2009-01-01

    Patterning events during early eye formation determine retinal cell fate and can dictate the behavior of retinal ganglion cell (RGC) axons as they navigate toward central brain targets. The temporally and spatially regulated expression of bone morphogenetic proteins (BMPs) and their receptors in the retina are thought to play a key role in this process, initiating gene expression cascades that distinguish different regions of the retina, particularly along the dorsoventral axis. Here, we examine the role of BMP and a potential downstream effector, EphB, in retinotopic map formation in the lateral geniculate nucleus (LGN) and superior colliculus (SC). RGC axon behaviors during retinotopic map formation in wild type mice are compared with those in several strains of mice with engineered defects of BMP and EphB signaling. Normal RGC axon sorting produces axon order in the optic tract that reflects the dorsoventral position of the parent RGCs in the eye. A dramatic consequence of disrupting BMP signaling is a missorting of RGC axons as they exit the optic chiasm. This sorting is not dependent on EphB. When BMP signaling in the developing eye is genetically modified, RGC order in the optic tract and targeting in the LGN and SC are correspondingly disrupted. These experiments show that BMP signaling regulates dorsoventral RGC cell fate, RGC axon behavior in the ascending optic tract and retinotopic map formation in the LGN and SC through mechanisms that are in part distinct from EphB signaling in the LGN and SC. PMID:18614674

  11. Different ossification patterns of intermuscular bones in fish with different swimming modes

    PubMed Central

    Yao, Wenjie; Lv, Yaoping; Gong, Xiaoling; Wu, Jiaming; Bao, Baolong

    2015-01-01

    ABSTRACT Intermuscular bones are found in the myosepta in teleosts. However, there is very little information on the development and ossification of these intermuscular bones. In this study, we performed an in-depth investigation of the ossification process during development in zebrafish (Danio rerio) and Japanese eel (Anguilla japonica). In Japanese eel, a typical anguilliform swimmer, the intermuscular bones ossified predominantly from the anterior to the posterior. By contrast, in the zebrafish, a sub-carangiform or carangiform swimmer, the intermuscular bones ossified predominantly from the posterior to the anterior regions of the fish. Furthermore, tail amputation affected the ossification of the intermuscular bones. The length of the intermuscular bones in the posterior area became significantly shorter in tail-amputated zebrafish and Japanese eels, and both had less active and lower swimming speeds; this indicates that swimming might induce the ossification of the intermuscular bones. Moreover, when a greater length of tail was amputated in the zebrafish, the intermuscular bones became even shorter. Tail amputation affected the length and ossification of intermuscular bones in the anterior part of the fish, close to the head, differently between the two fish: they became significantly shorter in the zebrafish, but did not in the Japanese eel. This might be because tail amputation did not significantly affect the undulations in the anterior of the Japanese eel, especially near the head. This study shows that the ossification of intermuscular bones might be induced through mechanical force loadings that are produced by swimming. PMID:26603470

  12. Technology of Bare Tether Current Collection

    NASA Technical Reports Server (NTRS)

    Estes, Robert D.; Sanmartin, Juan R.; Martinez-Sanchez, Manuel

    1998-01-01

    The outstanding problem for useful applications of electrodynamic tethers is obtaining sufficient electron current from the ionospheric plasma. Bare tether collectors, in which the conducting tether itself, left uninsulated over kilometers of its length, acts as the collecting anode, promise to attain currents of 10 A or more from reasonably sized systems. Current collection by a bare tether is also relatively insensitive to drops in electron density, which are regularly encountered on each revolution of an orbit. This makes nighttime operation feasible. We show how the bare tether's high efficiency of current collection and ability to adjust to density variations follow from the orbital motion limited collection law of thin cylinders. We consider both upwardly deployed (power generation mode) and downwardly deployed (reboost mode) tethers, and present results that indicate how bare tether systems would perform as their magnetic and plasma environment varies in low earth orbit.

  13. Gene expression patterns related to osteogenic differentiation of bone marrow-derived mesenchymal stem cells during ex vivo expansion.

    PubMed

    Granchi, Donatella; Ochoa, Gorka; Leonardi, Elisa; Devescovi, Valentina; Baglìo, Serena Rubina; Osaba, Lourdes; Baldini, Nicola; Ciapetti, Gabriela

    2010-06-01

    Bone marrow is commonly used as a source of adult multipotent mesenchymal stem cells (MSCs), defined for their ability to differentiate in vitro into multiple lineages. The ex vivo-expanded MSCs are currently being evaluated as a strategy for the restoration of function in damaged skeletal tissue, both in cell therapy and tissue engineering applications. The aim of this study was to define gene expression patterns underlying the differentiation of MSCs into mature osteoblasts during the expansion in vitro, and to explore a variety of cell functions that cannot be easily evaluated using morphological, cytochemical, and biochemical assays. Cell cultures were obtained from bone marrow samples of six individuals undergoing total hip replacement, and a large-scale transcriptome analysis, using Affymetrix HG-U133A Plus 2.0 array (Affymetrix((R)), Santa Clara, CA), was performed at the occurrence of specific events, including the appearance of MSC surface markers, formation of colonies, and deposition of mineral nodules. We focused our attention on 213 differentially upregulated genes, some belonging to well-known pathways and some having one or more Gene Ontology annotations related to bone cell biology, including angiogenesis, bone-related genes, cell communication, development and morphogenesis, transforming growth factor-beta signaling, and Wnt signaling. Twenty-nine genes, whose role in bone cell pathophysiology has not been described yet, were found. In conclusion, gene expression patterns that characterize the early, intermediate, and late phases of the osteogenic differentiation process of ex vivo-expanded MSCs were defined. These signatures represent a useful tool to monitor the osteogenic process, and to analyze a broad spectrum of functions of MSCs cultured on scaffolds, especially when the constructs are conceived for releasing growth factors or other signals to promote bone regeneration.

  14. Tailored Surface Treatment of 3D Printed Porous Ti6Al4V by Microarc Oxidation for Enhanced Osseointegration via Optimized Bone In-Growth Patterns and Interlocked Bone/Implant Interface.

    PubMed

    Xiu, Peng; Jia, Zhaojun; Lv, Jia; Yin, Chuan; Cheng, Yan; Zhang, Ke; Song, Chunli; Leng, Huijie; Zheng, Yufeng; Cai, Hong; Liu, Zhongjun

    2016-07-20

    3D printed porous titanium (Ti) holds enormous potential for load-bearing orthopedic applications. Although the 3D printing technique has good control over the macro-sturctures of porous Ti, the surface properties that affect tissue response are beyond its control, adding the need for tailored surface treatment to improve its osseointegration capacity. Here, the one step microarc oxidation (MAO) process was applied to a 3D printed porous Ti6Al4V (Ti64) scaffold to endow the scaffold with a homogeneous layer of microporous TiO2 and significant amounts of amorphous calcium-phosphate. Following the treatment, the porous Ti64 scaffolds exhibited a drastically improved apatite forming ability, cyto-compatibility, and alkaline phosphatase activity. In vivo test in a rabbit model showed that the bone in-growth at the untreated scaffold was in a pattern of distance osteogenesis by which bone formed only at the periphery of the scaffold. In contrast, the bone in-growth at the MAO-treated scaffold exhibited a pattern of contact osteogenesis by which bone formed in situ on the entire surface of the scaffold. This pattern of bone in-growth significantly increased bone formation both in and around the scaffold possibly through enhancement of bone formation and disruption of bone remodeling. Moreover, the implant surface of the MAO-treated scaffold interlocked with the bone tissues through the fabricated microporous topographies to generate a stronger bone/implant interface. The increased osteoinetegration strength was further proven by a push out test. MAO exhibits a high efficiency in the enhancement of osteointegration of porous Ti64 via optimizing the patterns of bone in-growth and bone/implant interlocking. Therefore, post-treatment of 3D printed porous Ti64 with MAO technology might open up several possibilities for the development of bioactive customized implants in orthopedic applications.

  15. Bone biopsy practice patterns across Europe: the European renal osteodystrophy initiative-a position paper.

    PubMed

    Evenepoel, Pieter; D'Haese, Patrick; Bacchetta, Justine; Cannata-Andia, Jorge; Ferreira, Anibal; Haarhaus, Mathias; Mazzaferro, Sandro; Lafage Proust, Marie-Helene; Salam, Syazrah; Spasovski, Goce; Cozzolino, Mario

    2017-03-03

    Renal osteodystrophy (ROD) is a heterogeneous group of metabolic bone diseases complicating progressive chronic kidney disease (CKD). Bone biomarkers and bone imaging techniques may help to assess bone health and predict fractures in CKD but do have important inherent limitations. By informing on bone turnover and mineralization, a bone biopsy may help to guide prevention and treatment of ROD and its consequences. According to a recent survey conducted among European nephrologists, bone biopsies are performed rather exceptionally, both for clinical and research purposes. Obviously, clinical research in the field of ROD is threatened by vanishing clinical and pathological expertise, small patient cohorts and scientific isolation. In March 2016, the European Renal Osteodystrophy (EU-ROD) initiative was created under the umbrella of the ERA-EDTA CKD-mineral and bone disorder (MBD) Working Group to revitalize bone biopsy as a clinically useful tool in the diagnostic workup of CKD-MBD and to foster research on the epidemiology, implications and reversibility of ROD. As such, the EU-ROD initiative aims to increase the understanding of ROD and ultimately to improve outcomes in CKD patients.

  16. Patterns of variation and covariation in the shapes of mandibular bones of juvenile salmonids in the genus Oncorhynchus

    PubMed Central

    Watson, Sawyer; Couture, Ryan B.; McKibben, Natasha S.; Nichols, James T.; Richardson, Shannon E.; Noakes, David L. G.

    2016-01-01

    SUMMARY What is the nature of evolutionary divergence of the jaw skeleton within the genus Oncorhynchus? How can two associated bones evolve new shapes and still maintain functional integration? Here, we introduce and test a ‘concordance’ hypothesis, in which an extraordinary matching of the evolutionary shape changes of the dentary and angular articular serves to preserve their fitting together. To test this hypothesis, we examined morphologies of the dentary and angular articular at parr (juvenile) stage, and at three levels of biological organization – between salmon and trout, between sister species within both salmon and trout, and among three types differing in life histories within one species, O. mykiss. The comparisons show bone shape divergences among the groups at each level; morphological divergence between salmon and trout is marked even at this relatively early life history stage. We observed substantial matching between the two mandibular bones in both pattern and amount of shape variation, and in shape covariation across species. These findings strongly support the concordance hypothesis, and reflect functional and/or developmental constraint on morphological evolution. We present evidence for developmental modularity within both bones. The locations of module boundaries were predicted from the patterns of evolutionary divergences, and for the dentary, at least, would appear to facilitate its functional association with the angular articular. The modularity results suggest that development has biased the course of evolution. PMID:26372063

  17. A comparison of principal component analysis, partial least-squares and reduced-rank regressions in the identification of dietary patterns associated with bone mass in ageing Australians.

    PubMed

    Melaku, Yohannes Adama; Gill, Tiffany K; Taylor, Anne W; Adams, Robert; Shi, Zumin

    2017-06-12

    The relative advantages of dietary analysis methods, particularly in identifying dietary patterns associated with bone mass, have not been investigated. We evaluated principal component analysis (PCA), partial least-squares (PLS) and reduced-rank regressions (RRR) in determining dietary patterns associated with bone mass. Data from 1182 study participants (45.9% males; aged 50 years and above) from the North West Adelaide Health Study (NWAHS) were used. Dietary data were collected using a food frequency questionnaire (FFQ). Dietary patterns were constructed using PCA, PLS and RRR and compared based on the performance to identify plausible patterns associated with bone mineral density (BMD) and content (BMC). PCA, PLS and RRR identified two, four and four dietary patterns, respectively. All methods identified similar patterns for the first two factors (factor 1, "prudent" and factor 2, "western" patterns). Three, one and none of the patterns derived by RRR, PLS and PCA were significantly associated with bone mass, respectively. The "prudent" and dairy (factor 3) patterns determined by RRR were positively and significantly associated with BMD and BMC. Vegetables and fruit pattern (factor 4) of PLS and RRR was negatively and significantly associated with BMD and BMC, respectively. RRR was found to be more appropriate in identifying more (plausible) dietary patterns that are associated with bone mass than PCA and PLS. Nevertheless, the advantage of RRR over the other two methods (PCA and PLS) should be confirmed in future studies.

  18. The paradoxes in patterns and mechanism of bone marrow regeneration after irradiation. 1. Different volumes and doses.

    PubMed

    Scarantino, C W; Rubin, P; Constine, L S

    1984-10-01

    Bone marrow regeneration (BMR) following irradiation has been largely studied as a dose-effect phenomenon, however, a large literature has simultaneously developed utilizing a wide variety of volumes, both in clinical studies and in experimental studies. In human situations radiation treatment fields and the amount of bone marrow organ exposed have ranged from total body irradiation (small daily and total doses) to large field (half-body) single high doses encompassing 50% of the bone marrow, to segmental or localized field (50-25%). Volume factors, more than dose, determine patterns of suppression and regeneration which have been documented by a variety of assay systems. Experimental evidence is presented which indicates that high dose irradiation (500-1000 cGy) to large volumes of bone marrow (50%) does not completely suppress bone marrow regeneration but results in a rapid compensatory response. The nadir response of bone marrow CFUc-GM stem cell compartment was directly proportional to increasing doses of irradiation (200-2000 cGy) delivered to a single limb. Immediate depression of CFUc-GM was followed by an increase proliferative phase with the most notable difference observed in doses less than or greater than 1000 rad. Following doses of 500 and 1000 rad to large field (half-body), an immediate depression was again observed followed by an immediate and greater compensatory response particularly after the 1000 rad dose. Comparisons ae made between the small and larger volumes at similar doses and indicate a greater overall compensatory response after the larger field irradiation, being more rapid in onset particularly after the 1000 rad dose. Although in-field regeneration of bone marrow occurs after single dose radiation to different volumes of bone marrow, experimental and clinical evidence from protracted conventional doses of irradiation to different volumes of bone marrow (greater or less than 50%) indicate significantly different response mechanisms

  19. Age-related differences in the bone mineralization pattern of rats following exercise

    SciTech Connect

    McDonald, R.; Hegenauer, J.; Saltman, P.

    1986-07-01

    The effect of 12 weeks of treadmill exercise on the mineralization of trabecular and cortical bone was studied in rats 7, 14, and 19 months of age. Bone mineralization was evaluated by measuring concentrations of Ca, Mg, and hydroxyproline as well as uptake of 45Ca concentration in the femur, humerus, rib and calvaria. The 7- and 14-month-old rats increased mineralization in those cortical bones directly involved in exercise. The 19-month animal responded to exercise by increasing mineralization in all bones examined, including the nonweight bearing trabecular calvaria and cortical rib. From these data, it is apparent that the older animals undergo a total skeletal mineralization in response to exercise compared with local adaptation in the younger animal. Further, we provide evidence to support the use of the rat as a model in which to study mammalian bone physiology during the aging process.

  20. Patterns of Practice in Palliative Radiotherapy for Painful Bone Metastases: A Survey in Japan

    SciTech Connect

    Nakamura, Naoki; Shikama, Naoto; Wada, Hitoshi; Harada, Hideyuki; Nozaki, Miwako; Nagakura, Hisayasu; Tago, Masao; Oguchi, Masahiko; Uchida, Nobue

    2012-05-01

    Purpose: To determine the current patterns of practice in Japan and to investigate factors that may make clinicians reluctant to use single-fraction radiotherapy (SF-RT). Methods and Materials: Members of the Japanese Radiation Oncology Study Group (JROSG) completed an Internet-based survey and described the radiotherapy dose fractionation they would recommend for four hypothetical cases describing patients with painful bone metastasis (BM). Case 1 described a patient with an uncomplicated painful BM in a non-weight-bearing site from non-small-cell lung cancer. Case 2 investigated whether management for a case of uncomplicated spinal BM would be different from that in Case 1. Case 3 was identical with Case 2 except for the presence of neuropathic pain. Case 4 investigated the prescription for an uncomplicated painful BM secondary to oligometastatic breast cancer. Radiation oncologists who recommended multifraction radiotherapy (MF-RT) for Case 2 were asked to explain why they considered MF-RT superior to SF-RT. Results: A total of 52 radiation oncologists from 50 institutions (36% of JROSG institutions) responded. In all four cases, the most commonly prescribed regimen was 30 Gy in 10 fractions. SF-RT was recommended by 13% of respondents for Case 1, 6% for Case 2, 0% for Case 3, and 2% for Case 4. For Case 4, 29% of respondents prescribed a high-dose MF-RT regimen (e.g., 50 Gy in 25 fractions). The following factors were most often cited as reasons for preferring MF-RT: 'time until first increase in pain' (85%), 'incidence of spinal cord compression' (50%), and 'incidence of pathologic fractures' (29%). Conclusions: Japanese radiation oncologists prefer a schedule of 30 Gy in 10 fractions and are less likely to recommend SF-RT. Most Japanese radiation oncologists regard MF-RT as superior to SF-RT, based primarily on the time until first increase in pain.

  1. [General patterns of bone atrophy in the absence of a weight load on the skeleton].

    PubMed

    Stupakov, G P; Kazeĭkin, V S; Volozhin, A I

    1983-01-01

    The rate of atrophic changes in spongy bones of the weightless man was estimated, using studies of human, dog and rat bones, as well as observations of neurological patients bed-stricken for a long time. Taking into consideration data on the literature on the bone status and mineral balance in real and simulated space flights, two models were built. The models make it possible to estimate osteoporosis of spongy bones of the axial skeleton in the absence of weight loading. One of the models--an intraspecies model for the human population--is based on the experimentally found rate of the physiological rearrangement of various spongy bones. The other--interspecies--model is built with reference to the parameters determining the rate, i. e. bone density and metabolism. The average monthly rates of axial bone losses calculated by means of the two independent methods are essentially identical. The data obtained allow prediction of the decrease of tolerance to head-to-feet impact acceleration as a function of flight duration.

  2. Fishbone Diagrams: Organize Reading Content with a "Bare Bones" Strategy

    ERIC Educational Resources Information Center

    Clary, Renee; Wandersee, James

    2010-01-01

    Fishbone diagrams, also known as Ishikawa diagrams or cause-and-effect diagrams, are one of the many problem-solving tools created by Dr. Kaoru Ishikawa, a University of Tokyo professor. Part of the brilliance of Ishikawa's idea resides in the simplicity and practicality of the diagram's basic model--a fish's skeleton. This article describes how…

  3. Fishbone Diagrams: Organize Reading Content with a "Bare Bones" Strategy

    ERIC Educational Resources Information Center

    Clary, Renee; Wandersee, James

    2010-01-01

    Fishbone diagrams, also known as Ishikawa diagrams or cause-and-effect diagrams, are one of the many problem-solving tools created by Dr. Kaoru Ishikawa, a University of Tokyo professor. Part of the brilliance of Ishikawa's idea resides in the simplicity and practicality of the diagram's basic model--a fish's skeleton. This article describes how…

  4. Bare Bones Young Adult Services: Tips for Public Library Generalists.

    ERIC Educational Resources Information Center

    Vaillancourt, Renee J.

    This book is a hands-on guide to the philosophy and practice of young adult services in the public libraries. The following chapters are included: (1) "Young Adult Services Philosophy," including reasons to serve teens, why teens are the way they are, who serves young adults, and how to interact with teens; (2) "Youth Participation," including…

  5. Bare Bones Young Adult Services: Tips for Public Library Generalists.

    ERIC Educational Resources Information Center

    Vaillancourt, Renee J.

    This book is a hands-on guide to the philosophy and practice of young adult services in the public libraries. The following chapters are included: (1) "Young Adult Services Philosophy," including reasons to serve teens, why teens are the way they are, who serves young adults, and how to interact with teens; (2) "Youth Participation," including…

  6. Bone health as a function of adipokines and vitamin D pattern in elderly patients.

    PubMed

    Pedone, Claudio; Napoli, Nicola; Pozzilli, Paolo; Lauretani, Fulvio; Bandinelli, Stefania; Ferrucci, Luigi; Rossi, Francesca Flavia; Antonelli-Incalzi, Raffaele

    2013-12-01

    Adiponectin, leptin, and resistin are involved in bone metabolism, but the evidence regarding their effects is not conclusive. We analyzed the relationship between these adipokines, vitamin D, and bone health using a cluster analysis approach. We used cross-sectional data coming from the InCHIANTI study, in which bone density and area were estimated using computed tomography. The sample size was 690 (women, 57.5%; mean age, 75.2 years; range, 65-102). Five clusters were generated on the basis of gender, age, adipokines, and vitamin D concentrations. The clusters were characterized, respectively, by higher resistin and older age (hR-O, n=134), higher vitamin D and younger age (hD-Y, n=152), higher adiponectin (hA, n=65), and higher leptin (hL, n=52). The last cluster had intermediate values of all the constituting variables (I, n=287). The clusters were compared with respect to bone parameters and clinical characteristics. Cluster hR-O had the lowest total and cortical bone density. Cluster hD-Y had the lowest adiponectin (9.29 g/mL) and leptin (7.9 ng/mL) serum concentrations, the highest prevalence of men (71.1%), and total/cortical bone density and area. No statistically significant difference across clusters was observed for age- and sex-standardized measures of bone mineral density and bone area, but leptin was associated with these parameters in a linear model adjusted for age, gender, vitamin D, resistin, and leptin. In an elderly population, age and sex almost completely explain the variability in bone status across cluster characterized by different levels of circulating adipokines and vitamin D. The role of leptin, however, seems worthy of consideration.

  7. Effects of cryosurgery on the healing pattern of rabbit mandibular bone. A triple fluorochrome labelling study.

    PubMed

    Kuylenstierna, R; Nathanson, A; Lundquist, P G

    1981-01-01

    The reparative process of rabbit mandibular bone injured by cryosurgery was studied by a triple fluorochromic method. The regeneration started late, when compared with fracture healing, and reached its maximum some 4-8 weeks after cryosurgery. A normal distribution of fluorochromes was registered after l2 weeks. The regeneration occurred mainly through growth from the marrow cavity region where the cryogenic impact may have stimulated osteogenesis from surviving endosteum and bone marrow. The destroyed periosteum at the site of the probe-tip attachment did not regenerate, although new bone formation of periosteal origin was noticed at the border of the injured cortex. The general distribution of fluorochromes seemed to follow closely the autoradiographic image obtained using 99TcmMDP in a similar experiment, suggesting comparable ways of accumulation in bone tissue.

  8. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare power...

  9. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare power...

  10. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare power...

  11. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare power...

  12. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare...

  13. Heterogeneous rare earth element (REE) patterns and concentrations in a fossil bone: Implications for the use of REE in vertebrate taphonomy and fossilization history

    NASA Astrophysics Data System (ADS)

    Suarez, Celina A.; Macpherson, G. L.; González, Luis A.; Grandstaff, David E.

    2010-05-01

    A bone fragment (CGDQ-3) of Falcariusutahensis, a therizinosaur from the Early Cretaceous Cedar Mountain Formation, Utah, contained within a carbonate nodule, was analyzed by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) in order to investigate REE variability within a thin-walled phalanx. Previous studies have found depth-related REE pattern variations; however, in CGDQ-3 variation occurs along the circumference of the bone. NASC-normalized REE patterns and concentrations vary between two apparent end members. A light-REE enriched (LREE) pattern, similar to solution ICP-MS analysis of this bone, characterizes approximately two-thirds of the bone fragment. Total REE concentrations are high and do not vary significantly from the periosteal surface to the medullar surface. Conversely, the remaining one-third of the bone has REE patterns that are MREE-depleted and low in total REE concentrations. REE concentrations in this part of the bone do not vary significantly from the periosteal to the medullar surface. A positive Ce anomaly is found throughout the entire bone, and is greatest within the LREE-enriched portion of the bone. This, in combination with the LREE-enrichment, suggests that the bone fossilized under reducing conditions. The distance between the LREE-enriched and MREE-depleted regions is less than 1 mm. Isotopic and petrographic analyses of the bone and surrounding carbonate matrix suggest the REE patterns in the bone were the result of partial fossilization/incomplete filling of micro-pore spaces around bone crystallites in an environment with changing redox conditions. The lower, MREE-depleted part of the bone fossilized contemporaneously with a pendant cement that formed on the underside of the bone in the vadose zone. Formation of the pendant cement restricted water flow through the bone, isolating the lower portion, which incorporated a MREE-depleted pattern. The upper part of the bone (LREE-enriched side) fossilized under

  14. Grazing intensity and spatial heterogeneity in bare soil in a grazing-resistant grassland

    USDA-ARS?s Scientific Manuscript database

    Spatial patterns in rangeland vegetation serve as indicators of rangeland condition and are an important component of wildlife habitat. We illustrate the use of very-large-scale aerial photography (VLSA) to quantify spatial patterns in bare soil of the northeastern Colorado shortgrass steppe. Using ...

  15. Pattern of healing of calvarial bone in the rat following application of the erbium-YAG laser.

    PubMed

    el Montaser, M A; Devlin, H; Sloan, P; Dickinson, M R

    1997-01-01

    The aim of this study was to examine the pattern of healing in rat calvarial defects prepared with the erbium-YAG laser, using the "guided tissue regeneration" technique [Dahlin et al., Scand J Plast Reconstr Hand Surg 1990;24: 13-19]. PTFE membranes were placed over the lased skull defects and the skin wounds sutured. Rats were killed humanely at intervals after surgery and the skulls processed for paraffin wax histology. A further group of mature rats was killed humanely and the calvariae removed. Slots were prepared using the erbium-YAG laser and immediately examined under the environmental scanning electron microscope (ESEM) in hydrated conditions, which avoided drying artefact. An amorphous, mineral-rich carbon layer surrounds the lased bone defect, which in the in vivo experiments was seen as a basophilic zone that was resistant to resorption. Bone infilling of the lased defect was retarded by delayed resorption of the amorphous, mineral-rich carbon layer.

  16. Patterns of activity adaptation in humeral trabecular bone in Neolithic humans and present-day people.

    PubMed

    Scherf, Heike; Wahl, Joachim; Hublin, Jean-Jacques; Harvati, Katerina

    2016-01-01

    The annual turnover rate of trabecular bone by far exceeds that of cortical bone and, therefore, is very sensitive to its daily loading regime. Here we test the hypothesis that the study of the trabecular bone architecture of the human humerus is able to differentiate between different habitual manual activities. For this purpose, we compared the trabecular architecture of the humeral head in a Neolithic population to that of a sample of contemporary Europeans using micro-computed tomography (microCT). We defined in each specimen a spherical volume of interest with a diameter of 57.5 ± 2.5% of the maximal diameter of the humeral head to metrically analyze the bulk of humeral head trabecular architecture. We subsequently quantified the trabecular architectures in the VOIs, measuring seven standard 3D-morphometric parameters, and used univariate and multivariate statistical analyses for comparisons within and between populations. Univariate statistical analysis showed significant differences in a combination of 3D-morphometric parameters. A principal components analysis of the 3D-morphometrics of the trabecular architectures separated the Neolithic from the contemporary samples on the basis of differences in their gross trabecular architecture, including differences in the bone volume fraction (BV/TV), the number of trabeculae per unit length (Tb N), and the distance between trabeculae (Tb Sp). We interpret the significant differences found in the humeral trabecular bone of the Neolithic and the contemporary group as likely reflecting the distinct manual working routines. The trabecular bone configuration in the Neolithic sample shows presumably functional signatures of prehistoric subsistence techniques and activity levels. © 2015 Wiley Periodicals, Inc.

  17. Associations of breast-feeding patterns and introduction of solid foods with childhood bone mass: The Generation R Study.

    PubMed

    van den Hooven, Edith H; Gharsalli, Mounira; Heppe, Denise H M; Raat, Hein; Hofman, Albert; Franco, Oscar H; Rivadeneira, Fernando; Jaddoe, Vincent W V

    2016-03-28

    Breast-feeding has been associated with later bone health, but results from previous studies are inconsistent. We examined the associations of breast-feeding patterns and timing of introduction of solids with bone mass at the age of 6 years in a prospective cohort study among 4919 children. We collected information about duration and exclusiveness of breast-feeding and timing of introduction of any solids with postnatal questionnaires. A total body dual-energy X-ray absorptiometry scan was performed at 6 years of age, and bone mineral density (BMD), bone mineral content (BMC), area-adjusted BMC (aBMC) and bone area (BA) were analysed. Compared with children who were ever breast-fed, those never breast-fed had lower BMD (-4·62 mg/cm2; 95 % CI -8·28, -0·97), BMC (-8·08 g; 95 % CI -12·45, -3·71) and BA (-7·03 cm2; 95 % CI -12·55, -1·52) at 6 years of age. Among all breast-fed children, those who were breast-fed non-exclusively in the first 4 months had higher BMD (2·91 mg/cm2; 95 % CI 0·41, 5·41) and aBMC (3·97 g; 95 % CI 1·30, 6·64) and lower BA (-4·45 cm2; 95 % CI -8·28, -0·61) compared with children breast-fed exclusively for at least 4 months. Compared with introduction of solids between 4 and 5 months, introduction <4 months was associated with higher BMD and aBMC, whereas introduction between 5 and 6 months was associated with lower aBMC and higher BA. Additional adjustment for infant vitamin D supplementation did not change the results. In conclusion, results from the present study suggest that ever breast-feeding compared with never breast-feeding is associated with higher bone mass in 6-year-old children, but exclusive breast-feeding for 4 months or longer was not positively associated with bone outcomes.

  18. Evaluation of opening pattern and bone neoformation at median palatal suture area in patients submitted to surgically assisted rapid maxillary expansion (SARME) through cone beam computed tomography

    PubMed Central

    SALGUEIRO, Daniel Gomes; RODRIGUES, Vitor Hugo Leite de Oliveira; TIEGHI, Victor; de MENEZES, Carolina Carmo; GONÇALES, Eduardo Sanches; FERREIRA, Osny

    2015-01-01

    Surgically assisted rapid maxillary expansion (SARME) is the treatment of choice to adult patients even with severe transversal maxillary discrepancies. However, the adequate retention period to achieve the bone remodeling, thus assuring treatment stability, is controversial. Objective To evaluate the opening pattern and bone neoformation process at the midpalatal suture in patients submitted to surgically assisted (SARME) through cone beam computed tomography (CBCT). Material and Methods Fourteen patients were submitted to SARME through subtotal Le Fort I osteotomy. Both the opening pattern and the mean bone density at midpalatal suture area to evaluate bone formation were assessed pre- and post-operatively (15, 60 and 180 days) through CBCT. Results Type I opening pattern (from anterior to posterior nasal spine) occurred in 12 subjects while type II opening pattern (from anterior nasal spine to transverse palatine suture) occurred in 2 individuals. The 180-day postoperative mean (PO 180) of bone density value was 49.9% of the preoperative mean (Pre) value. Conclusions The opening pattern of midpalatal suture is more related to patients’ age (23.9 years in type I and 33.5 years in type II) and surgical technique. It was not possible to observe complete bone formation at midpalatal suture area at the ending of the retention period studied (180 days). PMID:26398512

  19. Measurement of strain distribution in cortical bone around miniscrew implants used for orthodontic anchorage using digital speckle pattern interferometry

    NASA Astrophysics Data System (ADS)

    Kumar, Manoj; Agarwal, Rupali; Bhutani, Ravi; Shakher, Chandra

    2016-05-01

    An application of digital speckle pattern interferometry (DSPI) for the measurement of deformations and strain-field distributions developed in cortical bone around orthodontic miniscrew implants inserted into the human maxilla is presented. The purpose of this study is to measure and compare the strain distribution in cortical bone/miniscrew interface of human maxilla around miniscrew implants of different diameters, different implant lengths, and implants of different commercially available companies. The technique is also used to measure tilt/rotation of canine caused due to the application of retraction springs. The proposed technique has high sensitivity and enables the observation of deformation/strain distribution. In DSPI, two specklegrams are recorded corresponding to pre- and postloading of the retraction spring. The DSPI fringe pattern is observed by subtracting these two specklegrams. Optical phase was extracted using Riesz transform and the monogenic signal from a single DSPI fringe pattern. The obtained phase is used to calculate the parameters of interest such as displacement/deformation and strain/stress. The experiment was conducted on a dry human skull fulfilling the criteria of intact dental arches and all teeth present. Eight different miniscrew implants were loaded with an insertion angulation of 45 deg in the inter-radicular region of the maxillary second premolar and molar region. The loading of miniscrew implants was done with force level (150 gf) by nickel-titanium closed-coil springs (9 mm). The obtained results from DSPI reveal that implant diameter and implant length affect the displacement and strain distribution in cortical bone layer surrounding the miniscrew implant.

  20. Cross-sex pattern of bone mineral density in early onset gender identity disorder.

    PubMed

    Haraldsen, I R; Haug, E; Falch, J; Egeland, T; Opjordsmoen, S

    2007-09-01

    Hormonally controlled differences in bone mineral density (BMD) between males and females are well studied. The effects of cross-sex hormones on bone metabolism in patients with early onset gender identity disorder (EO-GID), however, are unclear. We examined BMD, total body fat (TBF) and total lean body mass (TLBM) in patients prior to initiation of sex hormone treatment and during treatment at months 3 and 12. The study included 33 EO-GID patients who were approved for sex reassignment and a control group of 122 healthy Norwegians (males, n=77; females, n=45). Male patients (n=12) received an oral dose of 50 mug ethinylestradiol daily for the first 3 months and 100 mug daily thereafter. Female patients (n=21) received 250 mg testosterone enantate intramuscularly every third week. BMD, TBF and TLBM were estimated using dual energy X-ray absorptiometry (DXA). In male patients, the DXA measurements except TBF were significantly lower compared to their same-sex control group at baseline and did not change during treatment. In female patients, the DXA measurements were slightly higher than in same-sex controls at baseline and also remained unchanged during treatment. In conclusion, this study reports that body composition and bone density of EO-GID patients show less pronounced sex differences compared to controls and that bone density was unaffected by cross-sex hormone treatment.

  1. Bioprinted Osteogenic and Vasculogenic Patterns for Engineering 3D Bone Tissue.

    PubMed

    Byambaa, Batzaya; Annabi, Nasim; Yue, Kan; Trujillo-de Santiago, Grissel; Alvarez, Mario Moisés; Jia, Weitao; Kazemzadeh-Narbat, Mehdi; Shin, Su Ryon; Tamayol, Ali; Khademhosseini, Ali

    2017-08-01

    Fabricating 3D large-scale bone tissue constructs with functional vasculature has been a particular challenge in engineering tissues suitable for repairing large bone defects. To address this challenge, an extrusion-based direct-writing bioprinting strategy is utilized to fabricate microstructured bone-like tissue constructs containing a perfusable vascular lumen. The bioprinted constructs are used as biomimetic in vitro matrices to co-culture human umbilical vein endothelial cells and bone marrow derived human mesenchymal stem cells in a naturally derived hydrogel. To form the perfusable blood vessel inside the bioprinted construct, a central cylinder with 5% gelatin methacryloyl (GelMA) hydrogel at low methacryloyl substitution (GelMALOW ) was printed. We also develop cell-laden cylinder elements made of GelMA hydrogel loaded with silicate nanoplatelets to induce osteogenesis, and synthesized hydrogel formulations with chemically conjugated vascular endothelial growth factor to promote vascular spreading. It was found that the engineered construct is able to support cell survival and proliferation during maturation in vitro. Additionally, the whole construct demonstrates high structural stability during the in vitro culture for 21 days. This method enables the local control of physical and chemical microniches and the establishment of gradients in the bioprinted constructs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Electron beam control for barely separated beams

    DOEpatents

    Douglas, David R.; Ament, Lucas J. P.

    2017-04-18

    A method for achieving independent control of multiple beams in close proximity to one another, such as in a multi-pass accelerator where coaxial beams are at different energies, but moving on a common axis, and need to be split into spatially separated beams for efficient recirculation transport. The method for independent control includes placing a magnet arrangement in the path of the barely separated beams with the magnet arrangement including at least two multipole magnets spaced closely together and having a multipole distribution including at least one odd multipole and one even multipole. The magnetic fields are then tuned to cancel out for a first of the barely separated beams to allow independent control of the second beam with common magnets. The magnetic fields may be tuned to cancel out either the dipole component or tuned to cancel out the quadrupole component in order to independently control the separate beams.

  3. Autofilet.pro: An Improved Method for Automated Removal of Herring-bone Pattern Noise from CCD Data

    NASA Astrophysics Data System (ADS)

    Jansen, R. A.; Collins, N. R.; Windhorst, R. A.

    We present an improved method for the automatic removal of the highly variable pattern-noise that was introduced in HST/STIS CCD data when it was switched to its redundant (``Side-2'') electronics in July 2001. While mainly a cosmetic nuisance for work on bright objects, this ``herring-bone'' noise severely limits the sensitivity at optical wavelengths for projects that aim to push STIS to its design limits. We build on the Fourier filtering technique described by Brown (2001) and present a method to automatically find and remove the power associated with the noise patterns in frequency space, while avoiding the introduction of ringing (aliasing) around genuine astronomical signal--in particular around stellar images, spectroscopic (emission) lines, and cosmic ray hits. We implement this method as an IDL procedure and show several applications. Details of the method will be discussed in Jansen et al. 2003.

  4. Bone microstructure and the evolution of growth patterns in Permo-Triassic therocephalians (Amniota, Therapsida) of South Africa.

    PubMed

    Huttenlocker, Adam K; Botha-Brink, Jennifer

    2014-01-01

    Therocephalians were a speciose clade of nonmammalian therapsids whose ecological diversity and survivorship of the end-Permian mass extinction offer the potential to investigate the evolution of growth patterns across the clade and their underlying influences on post-extinction body size reductions, or 'Lilliput effects'. We present a phylogenetic survey of limb bone histology and growth patterns in therocephalians from the Middle Permian through Middle Triassic of the Karoo Basin, South Africa. Histologic sections were prepared from 80 limb bones representing 11 genera of therocephalians. Histologic indicators of skeletal growth, including cortical vascularity (%CV) and mean primary osteon diameters (POD), were evaluated in a phylogenetic framework and assessed for correlations with other biologically significant variables (e.g., size and robusticity). Changes in %CV and POD correlated strongly with evolutionary changes in body size (i.e., smaller-bodied descendants tended to have lower %CV than their larger-bodied ancestors across the tree). Bone wall thickness tended to be high in early therocephalians and lower in the gracile-limbed baurioids, but showed no general correlation with cross-sectional area or degree of vascularity (and, thus, growth). Clade-level patterns, however, deviated from previously studied within-lineage patterns. For example, Moschorhinus, one of few therapsid genera to have survived the extinction boundary, demonstrated higher %CV in the Triassic than in the Permian despite its smaller size in the extinction aftermath. Results support a synergistic model of size reductions for Triassic therocephalians, influenced both by within-lineage heterochronic shifts in survivor taxa (as reported in Moschorhinus and the dicynodont Lystrosaurus) and phylogenetically inferred survival of small-bodied taxa that had evolved short growth durations (e.g., baurioids). These findings mirror the multi-causal Lilliput patterns described in marine faunas, but

  5. Bone microstructure and the evolution of growth patterns in Permo-Triassic therocephalians (Amniota, Therapsida) of South Africa

    PubMed Central

    Botha-Brink, Jennifer

    2014-01-01

    Therocephalians were a speciose clade of nonmammalian therapsids whose ecological diversity and survivorship of the end-Permian mass extinction offer the potential to investigate the evolution of growth patterns across the clade and their underlying influences on post-extinction body size reductions, or ‘Lilliput effects’. We present a phylogenetic survey of limb bone histology and growth patterns in therocephalians from the Middle Permian through Middle Triassic of the Karoo Basin, South Africa. Histologic sections were prepared from 80 limb bones representing 11 genera of therocephalians. Histologic indicators of skeletal growth, including cortical vascularity (%CV) and mean primary osteon diameters (POD), were evaluated in a phylogenetic framework and assessed for correlations with other biologically significant variables (e.g., size and robusticity). Changes in %CV and POD correlated strongly with evolutionary changes in body size (i.e., smaller-bodied descendants tended to have lower %CV than their larger-bodied ancestors across the tree). Bone wall thickness tended to be high in early therocephalians and lower in the gracile-limbed baurioids, but showed no general correlation with cross-sectional area or degree of vascularity (and, thus, growth). Clade-level patterns, however, deviated from previously studied within-lineage patterns. For example, Moschorhinus, one of few therapsid genera to have survived the extinction boundary, demonstrated higher %CV in the Triassic than in the Permian despite its smaller size in the extinction aftermath. Results support a synergistic model of size reductions for Triassic therocephalians, influenced both by within-lineage heterochronic shifts in survivor taxa (as reported in Moschorhinus and the dicynodont Lystrosaurus) and phylogenetically inferred survival of small-bodied taxa that had evolved short growth durations (e.g., baurioids). These findings mirror the multi-causal Lilliput patterns described in marine faunas

  6. Characterization of the cytokine pattern of porcine bone marrow-derived cells treated with 1alpha,25(OH)D.

    PubMed

    Sipos, W; Duvigneau, J C; Schmoll, F; Exel, B; Hofbauer, G; Baravalle, G; Hartl, R T; Dobretsberger, M; Pietschmann, P

    2005-10-01

    The biologically active form of vitamine D(3) [1alpha,25(OH)(2)D(3)] has recently been described not only to influence bone metabolism but also to exert immunomodulating activities, which may have an impact on bone formation/resorption as well. In this study, we analysed the effects of 1alpha,25(OH)(2)D(3) on the cytokine pattern of porcine bone marrow-derived cells from piglets aged 1-3 weeks. After culture for 1 week, the number of osteoclasts was determined, with tartrate-resistant acid phosphatase (TRAP)-positive, multinucleated cells being considered osteoclasts. Cultured bone marrow cell-derived mRNA was subjected to semiquantitative RT-PCR specific for a panel of porcine cytokines (IL-1alpha, IL-6, IL-8, IL-10, and TNF-alpha). In addition, an immunofluorescence analysis using anti-porcine mAbs specific for IL-1beta, IL-2, IL-4, IL-6, IL-12, TNF-alpha, and IFN-gamma was performed. In order to prove the existence of a porcine homologue of the receptor activator of NF-kappaB ligand (RANKL) bone marrow cell- as well as porcine white blood cell-derived mRNA was investigated by RT-PCR using primer pairs specific for murine RANKL. Cell culture supernatant was analysed for soluble RANKL by means of an ELISA designed for quantification of human RANKL. By means of RT-PCR, expression of IL-1alpha, IL-6, IL-8, IL-10 and TNF-alpha mRNA could be found in cells cultured with and without 1alpha,25(OH)(2)D(3). Immunofluorescence analysis revealed that IL-1, IL-6, and TNF-alpha were produced by both stromal cells and osteoclasts. Besides its known osteoclastogenic effects, 1alpha,25(OH)(2)D(3) tended to downregulate the respective cytokines, but significantly upregulated RANKL expression. The homology between the porcine RANKL-specific sequence and the corresponding human RANKL sequence was 79%. The data found support the idea that porcine bone marrow cell cultures may provide a suitable alternative to murine systems in human osteological research.

  7. Radiologic bone remodeling pattern around DCPD-coated, metaphyseal-loading cementless short stems in elderly patients.

    PubMed

    Oh, Kwang-Jun; Mishra, Amit; Yang, Jae-Hyuk

    2014-07-01

    Concerns exist regarding using short stems during total hip arthroplasties performed in elderly patients. For this study, the authors assessed sequential bone remodeling findings in metaphyseal-loading short stems using serial radiography. A total of 100 consecutive primary THAs using short stems were performed in patients with an average age of 78.3 years. The presence and patterns of radiolucent lines, radiopaque lines, calcar rounding, proximal bone resorption, spot welds, cortical hypertrophy, and intramedullary bone formation around the distal tip were assessed. The final study group comprised 92 hips, and mean follow-up was 60±3 months (range, 48-72 months). At final follow-up, condensations of spot welds were noted in 84 (91.3%) hips. Spot weld formation occurred in all zones except 1 and 4. Calcar rounding was observed in 90 (97.8%) hips. Atrophy of the calcar was noted in 19 (20.6%) hips. Analysis of the proximal zones revealed reactive radiodense lines in zones 1 and 2 (tensile area/shoulder of stem) in 22 (23.9%) hips. A prominent reactive line around the tip of the stem was recorded in 32 (34.8%) hips on radiographs at final follow-up. However, there was no increase in space between the tip of the stem and the radiopaque line. No acetabular or femoral component migrated by more than 1 mm at final follow-up. No acetabular or femoral osteolysis was identified. The radiographic findings of metaphyseal-loading short stems in elderly patients suggest that 91.3% of implants were osseointegrated. No patient required stem revision. Metaphyseal-loading short stems in elderly patients provide continued fixation with adaptive bone remodeling. Copyright 2014, SLACK Incorporated.

  8. Computed tomography of temporal bone pneumatization. 1. Normal pattern and morphology

    SciTech Connect

    Virapongse, C.; Sarwar, M.; Bhimani, S.; Sasaki, C.; Shapiro, R.

    1985-09-01

    The pneumatization of 141 normal temporal bones on computed tomography (CT) was evaluated in 100 patients. Because of the controversy surrounding the sclerotic squamomastoid (mastoid), temporal bones with this finding were discarded. A CT index of pneumatization was based on the pneumatized area and the number of cells seen within a representative scanning section. Results suggest that squamomastoid pneumatization follows the classic normal distribution and does not correlate with age, gender, or laterality. A high degree of symmetry was found in 41 patients who had both ears examined. Air-cell configuration was variable. Air-cell size tended to increase progressively from the mastoid antrum. The scutum pseudotumor appearance caused by incomplete pneumatization was seen frequently, and should not be mistaken for mastoiditis or an osteoma. Thick sections producing partial-volume effect may also produce this spurious finding. Therefore, when searching for mucosal thickening due to mastoiditis, large air cells should preferably be analyzed.

  9. Three-dimensional fiber deposition of cell-laden, viable, patterned constructs for bone tissue printing.

    PubMed

    Fedorovich, Natalja E; De Wijn, Joost R; Verbout, Abraham J; Alblas, Jacqueline; Dhert, Wouter J A

    2008-01-01

    Organ or tissue printing, a novel approach in tissue engineering, creates layered, cell-laden hydrogel scaffolds with a defined three-dimensional (3D) structure and organized cell placement. In applying the concept of tissue printing for the development of vascularized bone grafts, the primary focus lies on combining endothelial progenitors and bone marrow stromal cells (BMSCs). Here we characterize the applicability of 3D fiber deposition with a plotting device, Bioplotter, for the fabrication of spatially organized, cell-laden hydrogel constructs. The viability of printed BMSCs was studied in time, in several hydrogels, and extruded from different needle diameters. Our findings indicate that cells survive the extrusion and that their subsequent viability was not different from that of unprinted cells. The applied extrusion conditions did not affect cell survival, and BMSCs could subsequently differentiate along the osteoblast lineage. Furthermore, we were able to combine two distinct cell populations within a single scaffold by exchanging the printing syringe during deposition, indicating that this 3D fiber deposition system is suited for the development of bone grafts containing multiple cell types.

  10. Water Accommodation on Bare and Coated Ice

    NASA Astrophysics Data System (ADS)

    Kong, Xiangrui

    2015-04-01

    A good understanding of water accommodation on ice surfaces is essential for quantitatively predicting the evolution of clouds, and therefore influences the effectiveness of climate models. However, the accommodation coefficient is poorly constrained within the literature where reported values vary by up to three orders of magnitude. In addition, the complexity of the chemical composition of the atmosphere plays an important role in ice phase behavior and dynamics. We employ an environmental molecular beam (EMB) technique to investigate molecular water interactions with bare and impurity coated ice at temperatures from 170 K to 200 K. In this work, we summarize results of water accommodation experiments on bare ice (Kong et al., 2014) and on ice coated by methanol (Thomson et al., 2013), butanol (Thomson et al., 2013) and acetic acid (Papagiannakopoulos et al., 2014), and compare those results with analogous experiments using hexanol and nitric acid coatings. Hexanol is chosen as a complementary chain alcohol to methanol and butanol, while nitric acid is a common inorganic compound in the atmosphere. The results show a strong negative temperature dependence of water accommodation on bare ice, which can be quantitatively described by a precursor model. Acidic adlayers tend to enhance water uptake indicating that the system kinetics are thoroughly changed compared to bare ice. Adsorbed alcohols influence the temperature dependence of the accommodation coefficient and water molecules generally spend less time on the surfaces before desorbing, although the measured accommodation coefficients remain high and comparable to bare ice for the investigated systems. We conclude that impurities can either enhance or restrict water uptake in ways that are influenced by several factors including temperature and type of adsorbant, with potential implications for the description of ice particle growth in the atmosphere. This work was supported by the Swedish Research Council and

  11. Tear patterns, surgical repair, and clinical outcomes of patellar tendon ruptures after anterior cruciate ligament reconstruction with a bone-patellar tendon-bone autograft.

    PubMed

    Benner, Rodney W; Shelbourne, K Donald; Urch, Scott E; Lazarus, David

    2012-08-01

    Patellar tendon ruptures are rare after graft harvest for anterior cruciate ligament (ACL) reconstruction. Few reports are available in the literature. To report the common tear patterns and results of treatment with tendon repair and cable augmentation. Case series; Level of evidence, 4. All tendon ruptures were repaired to bone with suture anchors and augmented with a Dall-Miles cable, followed by an aggressive rehabilitation protocol. The tear location was recorded. Range of motion, strength, and subjective survey testing were conducted preoperatively and postoperatively. Thirteen patellar tendon ruptures were found from our database of 5364 ACL reconstructions, for an incidence of 0.24%. Seven ruptures occurred from the patellar origin medially and the tibial attachment laterally in a Z-shaped pattern. Four were completely distal, and 2 were completely proximal ruptures. All patients exhibited early flexion loss, but 11 of 13 patients maintained full, terminal hyperextension throughout treatment. The mean postoperative side-to-side flexion deficit was 33° at 1 month, 6° at 3 months, and 3° at latest follow-up at a mean of 4.8 years after tendon repair (range, 1-16 years). By International Knee Documentation Committee (IKDC) criteria, 10 patients had normal flexion, and 3 were nearly normal at latest follow-up. Twelve patients had normal extension, and 1 had nearly normal extension at latest follow-up. Mean isokinetic quadriceps muscle strength was 68.7% of the other side at 3 months after repair and 100.0% at latest follow-up, occurring at a mean of 47.5 months (range, 12-120 months). At a mean of 2 years (range, 1-4 years) after repair, the mean modified Noyes subjective score was 89.8 ± 9.2. Patellar tendon ruptures are rare after ACL graft harvest. These ruptures usually occur in either a proximal-medial and distal-lateral pattern or an entirely distal pattern, in contrast to the proximal-only tear pattern commonly observed in unharvested patellar

  12. Rietveld Refinement on X-Ray Diffraction Patterns of Bioapatite in Human Fetal Bones

    PubMed Central

    Meneghini, Carlo; Dalconi, Maria Chiara; Nuzzo, Stefania; Mobilio, Settimio; Wenk, Rudy H.

    2003-01-01

    Bioapatite, the main constituent of mineralized tissue in mammalian bones, is a calcium-phosphate-based mineral that is similar in structure and composition to hydroxyapatite. In this work, the crystallographic structure of bioapatite in human fetuses was investigated by synchrotron radiation x-ray diffraction (XRD) and microdiffraction (μ-XRD) techniques. Rietveld refinement analyses of XRD and μ-XRD data allow for quantitative probing of the structural modifications of bioapatite as functions of the mineralization process and gestational age. PMID:12609904

  13. Raman spectroscopy demonstrates Amifostine induced preservation of bone mineralization patterns in the irradiated murine mandible

    PubMed Central

    Poushanchi, Behdod; Donneys, Alexis; Sarhaddi, Deniz; Gallagher, K. Kelly; Deshpande, Sagar S.; Goldstein, Steven A.; Morris, Michael D.; Buchman, Steven R.

    2013-01-01

    Purpose Adjuvant radiotherapy in the management of head and neck cancer remains severely debilitating. Fortunately, newly developed agents aimed at decreasing radiation-induced damage have shown great promise. Amifostine (AMF) is a compound, which confers radio-protection to the exposed normal tissues, such as bone. Our intent is to utilize Raman spectroscopy to demonstrate how AMF preserves the mineral composition of the murine mandible following human equivalent radiation. Methods Sprague Dawley rats were randomized into 3 experimental groups: control (n=5), XRT (n=5), and AMF–XRT (n=5). Both XRT and AMF groups underwent bioequivalent radiation of 70 Gy in 5 fractions to the left hemimandible. AMF–XRT received Amifostine prior to radiation. Fifty-six days post-radiation, the hemimandibles were harvested, and Raman spectra were taken in the region of interest spanning 2 mm behind the last molar. Bone mineral and matrix-specific Raman bands were analyzed using one-way ANOVA, with statistical significance at p<0.05. Results The full-width at half-maximum of the primary phosphate band (FWHM) and the ratio of carbonate/phosphate intensities demonstrated significant differences between AMF–XRT versus XRT (p<0.01) and XRT versus control (p<0.01). There was no difference between AMF–XRT and control (p>0.05) in both Raman metrics. Computer-aided spectral subtraction further confirmed these results where AMF–XRT was spectrally similar to the control. Interestingly, the collagen cross-link ratio did not differ between XRT and AMF–XRT (p<0.01) but was significantly different from the control (p<0.01). Conclusion Our novel findings demonstrate that AMF prophylaxis maintains and protects bone mineral quality in the setting of radiation. Raman spectroscopy is an emerging and exceptionally attractive clinical translational technology to investigate and monitor both the destructive effects of radiation and the therapeutic remediation of AMF on the structural, physical

  14. 30 CFR 57.12012 - Bare signal wires.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare signal wires. 57.12012 Section 57.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... and Underground § 57.12012 Bare signal wires. The potential on bare signal wires accessible to contact...

  15. 30 CFR 57.12012 - Bare signal wires.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Bare signal wires. 57.12012 Section 57.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... and Underground § 57.12012 Bare signal wires. The potential on bare signal wires accessible to contact...

  16. 30 CFR 57.12012 - Bare signal wires.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Bare signal wires. 57.12012 Section 57.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... and Underground § 57.12012 Bare signal wires. The potential on bare signal wires accessible to contact...

  17. Study of enhanced bare land index using Landsat ETM+ image

    NASA Astrophysics Data System (ADS)

    Dou, P.; Chen, Y.

    2016-12-01

    For most bare land index without considering the spectrum similarity between high reflectivity buildings and bare land on the ETM+ remote sensing image, this paper has proposed bareness area index(BAI) and short bareness area index(SBAI) by analysing the spectrum characteristics of high reflectivity buildings and bare land. The impact of vegetation and water body to BAI and SBAI was decreased by using SAVI(Soil Adjusted Vegetation Index) and MNDWI(Modified Normalized Difference Water Index). Based on BAI and SBAI, we also used IBI(Index-based Built-up Index) to build enhanced bare land index. Bare land differences between BAI and IBI, SBAI and IBI were stretched by using an exponential function. Imitating NDVI, EBAI(Enhanced Bareness Area Index) and ESBAI(Enhanced Short Bareness Area Index) was constructed. And finally a statistical analysis indicates that EBAI and ESBAI can make bare land positive and background object negative, and comparing most other bare land index, these tow index have higher accuracy and are more easier to find a threshold to separate bare land and other land use type while effectively suppressing noise.

  18. RGD-Binding Integrins in Prostate Cancer: Expression Patterns and Therapeutic Prospects against Bone Metastasis

    PubMed Central

    Sutherland, Mark; Gordon, Andrew; Shnyder, Steven D.; Patterson, Laurence H.; Sheldrake, Helen M.

    2012-01-01

    Prostate cancer is the third leading cause of male cancer deaths in the developed world. The current lack of highly specific detection methods and efficient therapeutic agents for advanced disease have been identified as problems requiring further research. The integrins play a vital role in the cross-talk between the cell and extracellular matrix, enhancing the growth, migration, invasion and metastasis of cancer cells. Progression and metastasis of prostate adenocarcinoma is strongly associated with changes in integrin expression, notably abnormal expression and activation of the β3 integrins in tumour cells, which promotes haematogenous spread and tumour growth in bone. As such, influencing integrin cell expression and function using targeted therapeutics represents a potential treatment for bone metastasis, the most common and debilitating complication of advanced prostate cancer. In this review, we highlight the multiple ways in which RGD-binding integrins contribute to prostate cancer progression and metastasis, and identify the rationale for development of multi-integrin antagonists targeting the RGD-binding subfamily as molecularly targeted agents for its treatment. PMID:24213501

  19. Treatment and pattern of bone metastases in 1094 patients with advanced breast cancer - Results from the prospective German Tumour Registry Breast Cancer cohort study.

    PubMed

    Schröder, Jan; Fietz, Thomas; Köhler, Andreas; Petersen, Volker; Tesch, Hans; Spring, Lisa; Fleitz, Annette; Jänicke, Martina; Marschner, Norbert

    2017-07-01

    A high proportion of patients with breast cancer develop bone metastases, yet data on routine treatment with bone-targeted agents (BTA) are rare. We report real-life outcome data of patients with breast cancer metastasised to the bone treated by office-based oncologists in Germany. The ongoing, prospective, multicentre, population-based cohort study Tumour Registry Breast Cancer (TMK) was started in 2007 in 140 centres across Germany. This interim analysis of 1094 patients with bone metastases revealed differences among the tumour subtypes: at start of first-line therapy, 36% of the patients with hormone receptor (HR)-positive and only 20% of the patients with HR-negative tumours presented with bone-only metastasis. The majority of patients with bone metastases (89%, n = 976) received BTA therapy. In 2014-2015, 37% of the patients received the bisphosphonate zoledronic acid and 36% the antibody denosumab. Median duration of BTA therapy was 20 months (interquartile range 31.5 months), starting a median of 3 weeks after diagnosis of bone metastases, and ending a median of 7 weeks before death. The median overall survival (OS) also varied among the types of metastasis at start of first-line therapy ranging from 54 months (95% confidence interval [CI] 37.6-70.8), 38 months (95% CI 29.4-44.2) to 28 months (95% CI 24.2-31.0) for patients with bone-only metastases, non-visceral with or without bone metastases and visceral with or without bone metastases respectively. We show that choice and duration of BTA therapies are in conformity with guidelines applicable in Germany. To our knowledge, this is the first presentation of data on incidence, metastatic pattern, treatment and survival of patients with bone metastases in routine practice. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  20. Joint loading and proximal tibia subchondral trabecular bone microarchitecture differ with walking gait patterns in end-stage knee osteoarthritis.

    PubMed

    Roberts, B C; Solomon, L B; Mercer, G; Reynolds, K J; Thewlis, D; Perilli, E

    2017-06-20

    To (1) stratify patient subgroups according to their distinct walking gait patterns in end-stage knee osteoarthritis (OA); (2) compare measures of joint loading and proximal tibia subchondral trabecular bone (STB) microarchitecture among these gait subgroups. Twenty-five knee OA patients undergoing total knee arthroplasty (TKA) had pre-operative gait analysis. Following surgery, excised tibial plateaus were micro-CT-scanned and STB microarchitecture analysed in four tibial condylar regions of interest. Peak knee moments were input to k-means cluster analysis, to identify subgroups with homogeneous gait patterns. Joint loading and STB microarchitecture parameters were compared among gait subgroups (Kruskal-Wallis, Bonferroni-corrected Mann-Whitney U tests). Three gait subgroups were revealed: biphasics (n = 7), flexors (n = 9), counter-rotators (n = 9). Peak knee adduction moment (KAM) and KAM impulse were significantly higher (P < 0.05) in biphasics than in flexors and counter-rotators (KAM = -0.65, -0.40 and -0.21 Nm/kg, respectively), suggesting a higher medial-to-lateral tibiofemoral load ratio in biphasics. Interestingly, STB medial-to-lateral bone volume fraction (BV/TV) ratio was also significantly higher (more than double) in biphasics and flexors than in counter-rotators (2.24, 2.00 and 1.00, respectively), whereas in biphasics it was only 10% higher than in flexors and not significantly so. Within the confines of the limited sample size, data suggests that different mechanisms between the biphasic and flexor gait subroups may generate comparable loads upon the tibial plateau and corresponding bony responses, despite significantly lower KAM indices in flexors. Hence, in flexor gait OA patients, conservative treatments designed to reduce KAM, may not be appropriate. Understanding joint loading among walking gait patterns and relationships to bone microarchitecture may aid at identifying/improving management of persons at risk for developing knee

  1. Electromagnetic signals from bare strange stars

    NASA Astrophysics Data System (ADS)

    Parisi, Alessandro

    2015-01-01

    Strange stars with a crystalline color superconducting crust can sustain large shear stresses, supporting torsional oscillations of large amplitude. We consider a simple model of strange star with a bare quark matter surface. When a torsional oscillation is excited, for example by a stellar glitch, the positive charge at the star surface oscillates, with typical kHz frequencies, for a 1km thick crust, to hundreds of Hz, for a 9km thick crust. Higher frequencies, of the order of few GHz, can be reached if the star crust is of the order of few centimeters thick. The estimated emitted power is of the order of 10^{45}{ erg/s}.

  2. Frequency and patterning of bone trauma in the late medieval population (13th-16th century) from Dugopolje, southern Croatia.

    PubMed

    Novak, Mario; Slaus, Mario

    2012-07-01

    The aim of this paper is to test the hypothesis of an increased level of interpersonal violence in Dugopolje during the late medieval period as testified by written sources. In order to accomplish this, an analysis and comparison of frequencies and patterning of long bone and craniofacial fractures between sex and age categories in the Dugopolje skeletal sample was performed. In total 209 excellently preserved adult skeletons were analysed: 111 males and 98 females. The total long bone fracture frequency is 1.5% (29/1910) with a significantly higher frequency in males compared to females. Most of the long bone injuries occurred as a result of accidents, probably due to rugged mountainous terrain, while a certain portion of trauma resulted from deliberate violence. Significantly higher fracture frequencies in males could be a result of a strict sexual division of labour where males performed more physically demanding and risky tasks, as witnessed by historical sources. 26 out of 119 complete adult crania (21.8%) exhibit skeletal trauma with significantly higher frequencies in males. Perimortem trauma was observed in one individual while antemortem healed sharp force lesions were registered in five individuals (all males). The predominance of frontal craniofacial injuries, as well as the presence ofperimortem trauma and sharp force lesions, suggests the presence of deliberate violence in this community. Although the indicators of deliberate violence were recorded predominantly in males, suggesting that intentional violence in Dugopolje was exclusively males' prerogative, the presence of nasal fracture in a female skeleton might point to a male towards female violence. Presented bioarchaeological data are in accordance with the written documents thus corroborating the claims of an increased level of deliberate interpersonal violence in the late medieval population from Dugopolje.

  3. Bare Conductive Tether for Decelerating a Spacecraft

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Vaughn, Jason; Welzyn, Ken; Ballance, Judy; Carroll, Joe; Lorenzini, Enrico; Estes, bob; Schuler, Pete; Mojazza, hamid; Lennhoff, John

    2007-01-01

    A document describes a prototype of electrically conductive tethers to be used primarily to decelerate spacecraft and/or generate electric power for the spacecraft. Like prior such tethers, this tether is designed so that when it is deployed from a spacecraft in orbit, its motion across the terrestrial magnetic field induces an electric current. The Lorentz force on the current decelerates the spacecraft. Optionally, the current can be exploited to convert some orbital kinetic energy to electric energy for spacecraft systems. Whereas the conductive portions of prior such tethers are covered with electrical insulation except for end electrodes that make contact with the ionosphere, this tether includes a conductive portion that is insulated along part of its length but deliberately left bare along a substantial remaining portion of its length to make contact with the ionosphere. The conductive portions of the tether are made of coated thin aluminum wires wrapped around strong, lightweight aromatic polyamide braids. The main advantages of the present partly-bare-tether design over the prior all-insulated-tether design include greater resistance to degradation by the impact of monatomic oxygen at orbital altitude and speed and greater efficiency in collecting electrons from the ionosphere.

  4. Urinary cytokines/chemokines pattern in patients with painful bone metastases undergoing external beam radiotherapy experiencing pain flare.

    PubMed

    Bushehri, Ahmad; Chow, Edward; Zhang, Liying; Azad, Azar; Vuong, Sherlyn; Pasetka, Mark; Zhou, Michelle; Hird, Amanda; Dennis, Kristopher; McDonald, Rachel; DeAngelis, Carlo

    2016-04-01

    External beam radiotherapy (EBRT) is a mainstay for treatment of painful bone metastases. Transient worsening of pain ("pain flare") occurs in 40% of patients. We investigated the pathophysiology of pain flare through assessment of changes in urinary cytokines/chemokines in patients receiving EBRT for painful bone metastases. Urine samples were collected from patients receiving a single 8 Gy fraction for painful bone metastases preparation, day 1 or 2 and on an additional day between days 3 to 5 post radiation. Patients completed a standardized pain and analgesic use diary daily for 10 days following radiation. Patients were deemed to have pain flare if they had a two-point increase from baseline worst pain on 0-10 scale and no decrease in analgesic intake or a 25% increase in analgesic intake with no decrease in worst pain. The Millipore Milliplex 42-Plex Cyto-kine/Chemokine Kit™ was used to measure urinary levels of a panel of cytokines/chemokines. Forty-six patients consented to the study of which 28 were evaluable (complete urine and diary data), and 83/84 urine samples were available for analysis. Pain flare was experienced by 11 patients (39%). The following cytokines/chemokines were detectable in at least 50% of the patients: EGF, fractalkine, GRO, IL-4, IL-8, interferon gamma induced protein 10 (IP-10), MCP-1, macrophage derived chemokine (MDC), PDGF-AA, sIL-2Ra, TGF-Alpha, VEGF. Comparing patients with or without pain flare EGF, fractalkine, GRO, IL-8, IP-10, MCP-1, MDC, sIL-2Ra, and TGF-alpha increased following radiation in both groups. Patients with pain flare have significant lower levels on IL-8, IP-10, and MDC over time. No specific time trend was noticed. Patients who experience pain flare appear to have a different pattern in urinary cytokine/chemokine levels than patients without pain flare. A larger study is required to confirm the possible role of cytokines/chemokines in predisposition to and/or the cause of pain flare following radiation to

  5. [Musculoskeletal rehabilitation and bone. A novel approach to mechanotransduction using cell-adhesion-patterned cells].

    PubMed

    Katanosaka, Yuki; Naruse, Keiji

    2010-04-01

    Human vascular endothelial cells form the interface between the bloodstream and vessel walls and are continuously subjected to mechanical stimulation. When endothelial cells are stretched cyclically, along one axis, they align perpendicular to the axis of stretch. We previously reported that applying a cyclic, uni-axial strain to cells induced tyrosine phosphorylation of focal adhesion kinase and stimulated mitogen-activated protein kinase. However, it is difficult to quantify and analyze the spatial distribution of tyrosine phosphorylation in these cells, as they form focal adhesions randomly. Recently, we developed a system to overcome this problem by preparing individual, uniform, patterned cells that could be stretched cyclically and uni-axially. In this system we were able to statistically analyze cellular responses in these patterned cells, when subjected to a cyclic, uni-axial strain, using fluorescent microscopy.

  6. The bone morphogenic protein antagonist gremlin regulates proximal-distal patterning of the lung.

    PubMed

    Lu, M M; Yang, H; Zhang, L; Shu, W; Blair, D G; Morrisey, E E

    2001-12-01

    The proximal-distal patterning of lung epithelium involves a complex series of signaling and transcriptional events resulting in the programmed differentiation of highly specialized cells for gas exchange and surfactant protein expression essential for postnatal lung function. The BMP signaling pathway has been shown to regulate cellular differentiation in the lung as well as other tissues. In this report, we show that the can family of related BMP antagonists, including gremlin, cer-1, PRDC, and Dan are expressed in the lung during embryonic development with gremlin expression observed in the proximal airway epithelium. The role of gremlin in lung development was explored by overexpressing it in the distal lung epithelium of transgenic mice using the human SP-C promoter. SP-C/gremlin transgenic mice exhibited a disruption of the proximal-distal patterning found in the airways of the mammalian lung. Expanded expression of the proximal epithelial cell markers CC10 and HFH-4 (Foxj1) was observed in the distal regions of transgenic lungs. Furthermore, smooth muscle alpha-actin expression was observed surrounding the distal airways of SP-C/gremlin mice, indicating a proximalization of distal lung tubules. These data suggest that gremlin plays an important role in lung morphogenesis by regulating the proximal-distal patterning of the lung during development. Copyright 2001 Wiley-Liss, Inc.

  7. Do Bare Rocks Exist on the Moon?

    NASA Technical Reports Server (NTRS)

    Allen, Carlton; Bandfield, Joshua; Greenhagen, Benjamin; Hayne, Paul; Leader, Frank; Paige, David

    2017-01-01

    Astronaut surface observations and close-up images at the Apollo and Chang'e 1 landing sites confirm that at least some lunar rocks have no discernable dust cover. However, ALSEP (Apollo Lunar Surface Experiments Package) measurements as well as astronaut and LADEE (Lunar Atmosphere and Dust Environment Explorer) orbital observations and laboratory experiments possibly suggest that a fine fraction of dust is levitated and moves across and above the lunar surface. Over millions of years such dust might be expected to coat all exposed rock surfaces. This study uses thermal modeling, combined with Diviner (a Lunar Reconnaissance Orbiter experiment) orbital lunar eclipse temperature data, to further document the existence of bare rocks on the lunar surface.

  8. Cell Fusion Reprogramming Leads to a Specific Hepatic Expression Pattern during Mouse Bone Marrow Derived Hepatocyte Formation In Vivo

    PubMed Central

    Arza, Elvira; Alvarez-Barrientos, Alberto; Fabregat, Isabel; Garcia-Bravo, Maria; Meza, Nestor W.; Segovia, Jose C.

    2012-01-01

    The fusion of bone marrow (BM) hematopoietic cells with hepatocytes to generate BM derived hepatocytes (BMDH) is a natural process, which is enhanced in damaged tissues. However, the reprogramming needed to generate BMDH and the identity of the resultant cells is essentially unknown. In a mouse model of chronic liver damage, here we identify a modification in the chromatin structure of the hematopoietic nucleus during BMDH formation, accompanied by the loss of the key hematopoietic transcription factor PU.1/Sfpi1 (SFFV proviral integration 1) and gain of the key hepatic transcriptional regulator HNF-1A homeobox A (HNF-1A/Hnf1a). Through genome-wide expression analysis of laser captured BMDH, a differential gene expression pattern was detected and the chromatin changes observed were confirmed at the level of chromatin regulator genes. Similarly, Tranforming Growth Factor-β1 (TGF-β1) and neurotransmitter (e.g. Prostaglandin E Receptor 4 [Ptger4]) pathway genes were over-expressed. In summary, in vivo BMDH generation is a process in which the hematopoietic cell nucleus changes its identity and acquires hepatic features. These BMDHs have their own cell identity characterized by an expression pattern different from hematopoietic cells or hepatocytes. The role of these BMDHs in the liver requires further investigation. PMID:22457803

  9. Classification of micro-CT images using 3D characterization of bone canal patterns in human osteogenesis imperfecta

    NASA Astrophysics Data System (ADS)

    Abidin, Anas Z.; Jameson, John; Molthen, Robert; Wismüller, Axel

    2017-03-01

    Few studies have analyzed the microstructural properties of bone in cases of Osteogenenis Imperfecta (OI), or `brittle bone disease'. Current approaches mainly focus on bone mineral density measurements as an indirect indicator of bone strength and quality. It has been shown that bone strength would depend not only on composition but also structural organization. This study aims to characterize 3D structure of the cortical bone in high-resolution micro CT images. A total of 40 bone fragments from 28 subjects (13 with OI and 15 healthy controls) were imaged using micro tomography using a synchrotron light source (SRµCT). Minkowski functionals - volume, surface, curvature, and Euler characteristics - describing the topological organization of the bone were computed from the images. The features were used in a machine learning task to classify between healthy and OI bone. The best classification performance (mean AUC - 0.96) was achieved with a combined 4-dimensional feature of all Minkowski functionals. Individually, the best feature performance was seen using curvature (mean AUC - 0.85), which characterizes the edges within a binary object. These results show that quantitative analysis of cortical bone microstructure, in a computer-aided diagnostics framework, can be used to distinguish between healthy and OI bone with high accuracy.

  10. Comparison of interradicular distances and cortical bone thickness in Thai patients with Class I and Class II skeletal patterns using cone-beam computed tomography

    PubMed Central

    Khumsarn, Nattida; Patanaporn, Virush; Jotikasthira, Dhirawat

    2016-01-01

    Purpose This study evaluated and compared interradicular distances and cortical bone thickness in Thai patients with Class I and Class II skeletal patterns, using cone-beam computed tomography (CBCT). Materials and Methods Pretreatment CBCT images of 24 Thai orthodontic patients with Class I and Class II skeletal patterns were included in the study. Three measurements were chosen for investigation: the mesiodistal distance between the roots, the width of the buccolingual alveolar process, and buccal cortical bone thickness. All distances were recorded at five different levels from the cementoenamel junction (CEJ). Descriptive statistical analysis and t-tests were performed, with the significance level for all tests set at p<0.05. Results Patients with a Class II skeletal pattern showed significantly greater maxillary mesiodistal distances (between the first and second premolars) and widths of the buccolingual alveolar process (between the first and second molars) than Class I skeletal pattern patients at 10 mm above the CEJ. The maxillary buccal cortical bone thicknesses between the second premolar and first molar at 8 mm above the CEJ in Class II patients were likewise significantly greater than in Class I patients. Patients with a Class I skeletal pattern showed significantly wider mandibular buccolingual alveolar processes than did Class II patients (between the first and second molars) at 4, 6, and 8 mm below the CEJ. Conclusion In both the maxilla and mandible, the mesiodistal distances, the width of the buccolingual alveolar process, and buccal cortical bone thickness tended to increase from the CEJ to the apex in both Class I and Class II skeletal patterns. PMID:27358819

  11. Comparison of interradicular distances and cortical bone thickness in Thai patients with Class I and Class II skeletal patterns using cone-beam computed tomography.

    PubMed

    Khumsarn, Nattida; Patanaporn, Virush; Janhom, Apirum; Jotikasthira, Dhirawat

    2016-06-01

    This study evaluated and compared interradicular distances and cortical bone thickness in Thai patients with Class I and Class II skeletal patterns, using cone-beam computed tomography (CBCT). Pretreatment CBCT images of 24 Thai orthodontic patients with Class I and Class II skeletal patterns were included in the study. Three measurements were chosen for investigation: the mesiodistal distance between the roots, the width of the buccolingual alveolar process, and buccal cortical bone thickness. All distances were recorded at five different levels from the cementoenamel junction (CEJ). Descriptive statistical analysis and t-tests were performed, with the significance level for all tests set at p<0.05. Patients with a Class II skeletal pattern showed significantly greater maxillary mesiodistal distances (between the first and second premolars) and widths of the buccolingual alveolar process (between the first and second molars) than Class I skeletal pattern patients at 10 mm above the CEJ. The maxillary buccal cortical bone thicknesses between the second premolar and first molar at 8 mm above the CEJ in Class II patients were likewise significantly greater than in Class I patients. Patients with a Class I skeletal pattern showed significantly wider mandibular buccolingual alveolar processes than did Class II patients (between the first and second molars) at 4, 6, and 8 mm below the CEJ. In both the maxilla and mandible, the mesiodistal distances, the width of the buccolingual alveolar process, and buccal cortical bone thickness tended to increase from the CEJ to the apex in both Class I and Class II skeletal patterns.

  12. Bone metastases from breast cancer: associations between morphologic CT patterns and glycolytic activity on PET and bone scintigraphy as well as explorative search for influential factors.

    PubMed

    Sugihara, Tsutomu; Koizumi, Mitsuru; Koyama, Masamichi; Terauchi, Takashi; Gomi, Naoya; Ito, Yoshinori; Hatake, Kiyohiko; Sata, Naohiro

    2017-09-01

    This study aimed to compare the detection of bone metastases from breast cancer on F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and bone scintigraphy (BS). An explorative search for factors influencing the sensitivity or uptake of BS and FDG-PET was also performed. Eighty-eight patients with bone metastases from breast cancer were eligible for this study. Histological confirmation of bone metastases was obtained in 31 patients. The bone metastases were visually classified into four types based on their computed tomography (CT) appearance: osteoblastic, osteolytic, mixed, and negative. The sensitivity of BS and FDG-PET were obtained regarding CT type, adjuvant therapy, and the primary tumor characteristics. The FDG maximum standardized uptake value (SUVmax) was analyzed. The sensitivities of the three modalities (CT, BS, and FDG-PET) were 77, 89, and 94%, respectively. The sensitivity of FDG-PET for the osteoblastic type (69%) was significantly lower than that for the other types (P < 0.001), and the sensitivity of BS for the negative type (70%) was significantly lower than that for the others. Regarding tumor characteristics, the sensitivity of FDG-PET significantly differed between nuclear grade (NG)1 and NG2-3 (P = 0.032). The SUVmax of the osteoblastic type was significantly lower than that of the other types (P = 0.009). The SUVmax of NG1 was also significantly lower than that of NG2-3 (P = 0.011). No significant difference in FDG uptake (SUVmax) was detected between different histological types. Although FDG-PET is superior to BS for the detection of bone metastases from breast cancer, this technique has limitations in depicting osteoblastic bone metastases and NG1.

  13. Fire testing of bare uranium hexafluoride cylinders

    SciTech Connect

    Pryor, W.A.

    1991-12-31

    In 1965, the Oak Ridge Gaseous Diffusion Plant (ORGDP), now the K-25 Site, conducted a series of tests in which bare cylinders of uranium hexafluoride (UF{sub 6}) were exposed to engulfing oil fires for the US Atomic Energy Commission (AEC), now the US Department of Energy (DOE). The tests are described and the results, conclusions, and observations are presented. Two each of the following types of cylinders were tested: 3.5-in.-diam {times} 7.5-in.-long cylinders of Monel (Harshaw), 5.0-in.-diam {times} x 30-in.-long cylinders of Monel, and 8-in.-diam {times} 48-in.-long cylinders of nickel. The cylinders were filled approximately to the standard UF{sub 6} fill limits of 5, 55, and 250 lb, respectively, with a U-235 content of 0.22%. The 5-in.- and 8-in.-diam cylinders were tested individually with and without their metal valve covers. For the 3.5-in.-diam Harshaw cylinders and the 5.0-in.-diam cylinder without a valve cover, the valves failed and UF{sub 6} was released. The remaining 6 cylinders ruptured explosively in time intervals ranging from about 8.5 to 11 min.

  14. Fire testing of bare uranium hexafluoride cylinders

    SciTech Connect

    Pryor, W.A.

    1991-12-31

    In 1965, the Oak Ridge Gaseous Diffusion Plant (ORGDP), now the K-25 Site, conducted a series of tests in which bare cylinders of uranium hexafluoride (UF{sub 6}) were exposed to engulfing oil fires for the US Atomic Energy Commission (AEC), now the US Department of Energy (DOE). The tests are described and the results, conclusions, and observations are presented. Two each of the following types of cylinders were tested: 3.5-in.-diam {times} 7.5-in.-long cylinders of Monel (Harshaw), 5.0-in.-diam {times} 30-in.-long cylinders of Monel, and 8-in.-diam {times} 48-in.-long cylinders of nickel. The cylinders were filled approximately to the standard UF{sub 6} fill limits of 5, 55, and 250 lb, respectively, with a U-235 content of 0.22%. The 5-in.- and 8-in.-diam cylinders were tested individually with and without their metal valve covers. For the 3.5-in.-diam Harshaw cylinders and the 5.0-in.-diam cylinder without a valve cover the valves failed and UF{sub 6} was released. The remaining cylinders ruptured explosively in time intervals ranging from about 8.5 to 11 min.

  15. Routine use of antibiotic laden bone cement for primary total knee arthroplasty: impact on infecting microbial patterns and resistance profiles.

    PubMed

    Hansen, Erik N; Adeli, Bahar; Kenyon, Robert; Parvizi, Javad

    2014-06-01

    Antibiotic-laden bone cement (ALBC) is used in primary arthroplasties throughout Europe. In North America, ALBC is only FDA approved for revision arthroplasty after periprosthetic joint infection (PJI). No article has evaluated whether infecting microbial profile and resistance has changed with the introduction of ALBC. We hypothesized that prophylactic use of ALBC in primary total knee arthroplasty (TKA) has not had a significant impact on infecting pathogens, and antibiotic resistance profiles. A retrospective cohort analysis was conducted of all PJI patients undergoing primary TKA and total hip arthroplasty (THA) between January 2000 and January 2009. No significant change in the patterns of infecting PJI pathogens, and no notable increase in percentage resistance was found among organisms grown from patients with PJI that had received prophylactic antibiotic-loaded cement in their primary joint arthroplasty. Early findings suggest that routine prophylactic use of ALBC has not led to changes in infecting pathogen profile, nor has led to the emergence of antimicrobial resistance at our institution.

  16. Prenatal development of the human mandible. 3D reconstructions, morphometry and bone remodelling pattern, sizes 12-117 mm CRL.

    PubMed

    Radlanski, Ralf J; Renz, Herbert; Klarkowski, Marie C

    2003-10-01

    Human embryos and fetuses ( n=25) ranging from 12 to 117 mm CRL (crown-rump-length) were serially sectioned and the mandibles were reconstructed in 3D. In addition, characteristic areas of apposition, resorption and resting zones were projected onto the surface of the mandibular reconstructions after histological evaluation of the remodeling processes. Furthermore, morphometric data were taken to describe growth processes in horizontal views. In this way the changing outlines as seen in 3D could be correlated with the remodeling patterns and with the changes in growth. In these stages the mandible showed a general appositional growth, but resorption areas were found at the posterior margins of the mental foramen and at the lateral and medial posterior bony planes at concave surfaces. The bulging of bone underneath and over Meckel's cartilage could be recognized as active appositional growth areas. Meckel's cartilage itself lay in a trough which could be characterized by less apposition and even resorption. Questions were raised in how much the gap between our present knowledge of genetic expression of signaling molecules and the precise morphologic description of the mandibles can be bridged.

  17. Reduction of Rhizoctonia bare patch win wheat with barley rotations.

    USDA-ARS?s Scientific Manuscript database

    Rhizoctonia bare patch caused by Rhizoctonia solani AG-8 is a major fungal root disease in no-till cropping systems. In an 8-year experiment comparing various dryland no-till cropping systems near Ritzville, Washington, Rhizoctonia bare patch first appeared in year 3 and continued through year 8. ...

  18. The Semantics of Proper Names and Other Bare Nominals

    ERIC Educational Resources Information Center

    Izumi, Yu

    2012-01-01

    This research proposes a unified approach to the semantics of the so-called bare nominals, which include proper names (e.g., "Mary"), mass and plural terms (e.g., "water," "cats"), and articleless noun phrases in Japanese. I argue that bare nominals themselves are monadic predicates applicable to more than one…

  19. The Semantics of Proper Names and Other Bare Nominals

    ERIC Educational Resources Information Center

    Izumi, Yu

    2012-01-01

    This research proposes a unified approach to the semantics of the so-called bare nominals, which include proper names (e.g., "Mary"), mass and plural terms (e.g., "water," "cats"), and articleless noun phrases in Japanese. I argue that bare nominals themselves are monadic predicates applicable to more than one…

  20. Role of water in the tribochemical removal of bare silicon

    NASA Astrophysics Data System (ADS)

    Chen, Cheng; Xiao, Chen; Wang, Xiaodong; Zhang, Peng; Chen, Lei; Qi, Yaqiong; Qian, Linmao

    2016-12-01

    Nanowear tests of bare silicon against a SiO2 microsphere were conducted in air (relative humidity [RH] = 0%-89%) and water using an atomic force microscope. Experimental results revealed that the water played an important role in the tribochemical wear of the bare silicon. A hillock-like wear trace with a height of 0.7 nm was generated on the bare silicon surface in dry air. As the RH increased, the wear depth increased and reached the maximum level in water. Analysis of frictional dissipated energy suggested that the wear of the bare silicon was not dominated by mechanical interactions. High-resolution transmission electron microscopy detection demonstrated that the silicon atoms and crystal lattice underneath the worn area maintained integral perfectly and thus further confirmed the tribochemical wear mechanism of the bare silicon. Finally, the role of water in the tribochemical wear of the bare silicon may be explained by the following three aspects: the hydroxylation by hydroxyl ions auto-ionized in water, the hydrolytic reaction of water molecules, and the dissolution of the tribochemical product SiOmHn in liquid water. With increasing RH, a greater water amount would adsorb to the Si/SiO2 interface and induce a more serious tribochemical wear on the bare silicon surface. The results of this paper may provide further insight into the tribochemical removal mechanism of bare monocrystalline silicon and furnish the wider reaction cognition for chemical mechanical polishing.

  1. Patterns of Practice in Palliative Radiotherapy for Painful Bone Metastases: Impact of a Regional Rapid Access Clinic on Access to Care

    SciTech Connect

    Wu, Jackson S.Y.; Kerba, Marc; Wong, Rebecca K.S.; Mckimmon, Erin; Eigl, Bernhard; Hagen, Neil A.

    2010-10-01

    Purpose: External beam radiotherapy (RT) is commonly indicated for the palliation of symptomatic bone metastases, but there is evidence of underutilization of this treatment modality in palliative care for cancer populations. This study was conducted to investigate factors that influenced the use of palliative RT services at a regional comprehensive cancer center. Methods and Materials: A cohort of patients with radiographically confirmed bone metastases and first-time users of palliative RT between 2003 and 2005 was retrospectively reviewed from the time of initial diagnosis of bone metastases to death or last follow-up. Type of radiation treatment service provider used (rapid access or routine access) and patient-, tumor-, and treatment-related factors were analyzed for their influences on the number of treatment courses given over the duration of disease. Results: A total of 887 patients received 1,354 courses of palliative RT for bone metastases at a median interval of 4.0 months between courses. Thirty-three percent of patients required more than one RT course. Increased age and travel distance reduced the likelihood and number of treatment courses, while service through a rapid access clinic was independently associated with an increase in subsequent use of palliative RT. Conclusions: A rapid access service model for palliative RT facilitated access to RT. Travel distance and other factors remained substantial barriers to use of palliative RT services. The pattern of practice suggests an unmet need for symptom control in patients with bone metastases.

  2. Analysis of heel pad tissues mechanics at the heel strike in bare and shod conditions.

    PubMed

    Fontanella, C G; Forestiero, A; Carniel, E L; Natali, A N

    2013-04-01

    A combined experimental and numerical approach is used to investigate the interaction phenomena occurring between foot and footwear during the heel strike phase of the gait. Two force platforms are utilised to evaluate the ground reaction forces of a subject in bare and shod walking. The reaction forces obtained from the experimental tests are assumed as loading conditions for the numerical analyses using three dimensional models of the heel region and of the running shoe. The heel pad region, as fat and skin tissues, is described by visco-hyperelastic and fibre-reinforced hyperelastic formulations respectively and bone region by a linear orthotropic formulation. Different elastomeric foams are considered with regard to the outsole, the midsole and the insole layers. The mechanical properties are described by a hyperfoam formulation. The evaluation of the mechanical behaviour of the heel pad tissues at the heel strike in bare and shod conditions is performed considering different combinations of materials for midsole and insole layers. Results allow for the definition of the influence of different material characteristics on the mechanical response of the heel pad region, in particular showing the compressive stress differentiation in the bare and shod conditions.

  3. Development of a testing methodology to quantify bone load transfer patterns for multiple stemmed implants in a single bone with an application in the distal ulna.

    PubMed

    Austman, Rebecca L; Quenneville, Cheryl E; Beaton, Brendon J B; King, Graham J W; Gordon, Karen D; Dunning, Cynthia E

    2008-04-01

    Optimal parameters for many orthopaedic implants, such as stem length and material, are unknown. Geometry and mechanical properties of bone can vary greatly amongst cadaveric specimens, requiring a large number of specimens to test design variations. This study aimed to develop an experimental methodology to measure bone strains as a function of multiple implant stem designs in a single specimen, and evaluate its efficacy in the distal ulna. Eight fresh-frozen cadaveric ulnae were each instrumented with 12 uniaxial strain gauges on the medial and lateral surfaces of the bone. The proximal portion of each ulna was cemented in a custom-designed jig that allowed a medially directed force to be applied to the distal articular surface. An implant with a finely threaded stem was cemented into the canal by an experienced upper extremity orthopaedic surgeon. Six loads (5-30 N) were applied sequentially to the lateral surface of the prosthetic head using a materials testing machine. Testing was repeated after breaking the stem-cement bond, and after removing and reinserting the stem several times into the threaded cement mantle. Near the end of the testing period, the initial stem was reinserted and data were collected to determine if there was any change in bone properties or testing setup over time. Finally, a smooth stem was inserted for comparison to the threaded stem. Strain varied linearly with load (R(2)> or =0.99) for all testing scenarios. Bending strains were not affected by breaking the stem-cement bond (P=0.7), testing durations up to 18 h (P=0.7), nor the presence of threads when compared to a smooth stem (P>0.4). Furthermore, for all gauges, there was no interaction between the effect of the threads and level of applied load (P>0.1). This methodology should prove to be useful to compare stem designs of varying lengths and materials in the same bone, allowing for a direct comparison between implant designs for the ulna and other bones subjected primarily to

  4. Patterns of bone tracer uptake on SPECT-CT in symptomatic and asymptomatic patients with primary total hip arthroplasty.

    PubMed

    Schweizer, Thierry; Schiapparelli, Filippo-Franco; Rotigliano, Niccolo; Rasch, Helmut; Amsler, Felix; Hirschmann, Michael T

    2017-09-19

    The primary purpose of this study was to compare bone tracer uptake (BTU) on SPECT/CT in symptomatic and asymptomatic total hip arthroplasty (THA) and identify a possible relationship between BTU patterns and patient's symptoms. The secondary purpose was to investigate if the fixation methods (cemented versus uncemented) lead to different BTU patterns. A total of 58 THAs, 31 symptomatic (group S) and 27 asymptomatic (group AS), were prospectively collected and retrospectively analyzed. All symptomatic patients underwent standardized detailed history, clinical examination, radiographs and 99mTc-HDP SPECT/CT. BTU in SPECT/CT was quantified in three dimensions and anatomically localized in a scheme of quadrants and levels using a customized previously validated software. T tests were used on both quadrants and levels inside and between groups. A Pearson correlation was performed for BTU within the quadrants. An area under receiver operating characteristic curves was drawn in order to find a BTU value that could differentiate the two groups. Within the groups, patients with cemented and uncemented stems were compared for influences on BTU intensity. The causes of pain were identified in 61% of the patients. The most common problem was aseptic loosening (n = 12). In group AS, levels 1, 2 and 5 had similar BTUs. BTUs in these levels were significantly higher than in level 3, 4 and 6. In group S, no significant differences were seen in terms of BTU in level 1-5. However, BTU here was significantly higher than at level 6 (p < 0.001). In both groups, level 1, the superior, had a significantly higher BTU than level 2 (group AS p < 0.01, group S p < 0.05). Comparing the BTU of the two groups among levels, significant differences were found for level 4, level 5 and the entire stem areas (p < 0.05). The ROC curve calculated on the whole stem allowed identification of a BTU ratio of 3.1 that separated the 92.6% patients of group AS with BTU < 3.1 from the 54.8% of

  5. Bone graft

    MedlinePlus

    Autograft - bone; Allograft - bone; Fracture - bone graft; Surgery - bone graft; Autologous bone graft ... Fuse joints to prevent movement Repair broken bones (fractures) that have bone loss Repair injured bone that ...

  6. Chloride-hydrogen antiporters ClC-3 and ClC-5 drive osteoblast mineralization and regulate fine-structure bone patterning in vitro.

    PubMed

    Larrouture, Quitterie C; Nelson, Deborah J; Robinson, Lisa J; Liu, Li; Tourkova, Irina; Schlesinger, Paul H; Blair, Harry C

    2015-11-01

    Osteoblasts form an epithelium-like layer with tight junctions separating bone matrix from extracellular fluid. During mineral deposition, calcium and phosphate precipitation in hydroxyapatite liberates 0.8 mole of H(+) per mole Ca(+2). Thus, acid export is needed for mineral formation. We examined ion transport supporting osteoblast vectorial mineral deposition. Previously we established that Na/H exchangers 1 and 6 are highly expressed at secretory osteoblast basolateral surfaces and neutralize massive acid loads. The Na/H exchanger regulatory factor-1 (NHERF1), a pdz-organizing protein, occurs at mineralizing osteoblast basolateral surfaces. We hypothesized that high-capacity proton transport from matrix into osteoblast cytosol must exist to support acid transcytosis for mineral deposition. Gene screening in mineralizing osteoblasts showed dramatic expression of chloride-proton antiporters ClC-3 and ClC-5. Antibody localization showed that ClC-3 and ClC-5 occur at the apical secretory surface facing the bone matrix and in membranes of buried osteocytes. Surprisingly, the Clcn3(-/-) mouse has only mildly disordered mineralization. However, Clcn3(-/-) osteoblasts have large compensatory increases in ClC-5 expression. Clcn3(-/-) osteoblasts mineralize in vitro in a striking and novel trabecular pattern; wild-type osteoblasts form bone nodules. In mesenchymal stem cells from Clcn3(-/-) mice, lentiviral ClC-5 shRNA created Clcn3(-/-), ClC-5 knockdown cells, validated by western blot and PCR. Osteoblasts from these cells produced no mineral under conditions where wild-type or Clcn3(-/-) cells mineralize well. We conclude that regulated acid export, mediated by chloride-proton exchange, is essential to drive normal bone mineralization, and that CLC transporters also regulate fine patterning of bone.

  7. Resolving the anomaly of bare habitable ground in Daisyworld

    NASA Astrophysics Data System (ADS)

    Hankin, Robin K. S.; Mitchell, Neil

    2011-02-01

    The parable of Daisyworld places biological homeostasis on a non-teleological basis. However, one feature of Daisyworld is that, at equilibrium, the system appears to require habitable but bare ground. The presence of bare ground is an unavoidable consequence of the death rate parameter γ. Here, we simplify Watson and Lovelock's original formulation by removing γ and allowing instead the black and white daisies to infiltrate each others' territory. This device furnishes a model in which the area of bare ground asymptotically approaches zero. The infiltration process is modelled in terms of a parameter that is ecologically interpretable as a quantification of the incumbent advantage enjoyed by the dominant species.

  8. Severity and pattern of bone mineral loss in endocrine causes of osteoporosis as compared to age-related bone mineral loss

    PubMed Central

    Dutta, D; Dharmshaktu, P; Aggarwal, A; Gaurav, K; Bansal, R; Devru, N; Garga, UC; Kulshreshtha, B

    2016-01-01

    Background: Data are scant on bone health in endocrinopathies from India. This study evaluated bone mineral density (BMD) loss in endocrinopathies [Graves’ disease (GD), type 1 diabetes mellitus (T1DM), hypogonadotrophic hypogonadism (HypoH), hypergonadotropic hypogonadism (HyperH), hypopituitarism, primary hyperparathyroidism (PHPT)] as compared to age-related BMD loss [postmenopausal osteoporosis (PMO), andropause]. Materials and Methods: Retrospective audit of records of patients >30 years age attending a bone clinic from August 2014 to January 2016 was done. Results: Five-hundred and seven records were screened, out of which 420 (females:male = 294:126) were analyzed. A significantly higher occurrence of vitamin D deficiency and insufficiency was noted in T1DM (89.09%), HyperH (85%), and HypoH (79.59%) compared to age-related BMD loss (60.02%; P < 0.001). The occurrence of osteoporosis among females and males was 55.41% and 53.97%, respectively, and of osteopenia among females and males was 28.91% and 32.54%, respectively. In females, osteoporosis was significantly higher in T1DM (92%), HyperH (85%), and HypoH (59.26%) compared to PMO (49.34%; P < 0.001). Z score at LS, TF, NOF, and greater trochanter (GT) was consistently lowest in T1DM women. Among men, osteoporosis was significantly higher in T1DM (76.67%) and HypoH (54.55%) compared to andropause (45.45%; P = 0.001). Z score at LS, TF, NOF, GT, and TR was consistently lowest in T1DM men. In GD, the burden of osteoporosis was similar to PMO and andropause. BMD difference among the study groups was not significantly different after adjusting for body mass index (BMI) and vitamin D. Conclusion: Low bone mass is extremely common in endocrinopathies, warranting routine screening and intervention. Concomitant vitamin D deficiency compounds the problem. Calcium and vitamin D supplementations may improve bone health in this setting. PMID:27241810

  9. Markers of bone resorption and calcium metabolism are related to dietary intake patterns in male and female bed rest subjects

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.; Zwart, S. R.; Hargens, A. r.

    2006-01-01

    Dietary potassium and protein intakes predict net endogenous acid production in humans. Intracellular buffers, including exchangeable bone mineral, play a crucial role in balancing chronic acid-base perturbations in the body; subsequently, chronic acid loads can potentially contribute to bone loss. Bone is lost during space flight, and a dietary countermeasure would be desirable for many reasons. We studied the ability of diet protein and potassium to predict levels of bone resorption markers in males and females. Identical twin pairs (8 M, 7 F) were assigned to 2 groups: bed rest (sedentary, SED) or bed rest with supine treadmill exercise in a lower body negative pressure chamber (EX). Diet was controlled for 3 d before and 30 d of bed rest (BR). Urinary Ca, N-telopeptide (NTX), and pyridinium crosslinks (PYD) were measured before and on days 5, 12, 19, and 26 of BR. Data were analyzed by Pearson correlation (P<0.05). The ratio of dietary animal protein/potassium intake was not correlated with NTX before BR for males or females, but they were positively correlated in both groups of males during bed rest. Dietary animal protein/potassium and urine Ca were correlated before and during bed rest for the males, and only during bed rest for the females. Conversely, the ratio of dietary vegetable protein/potassium intake was negatively correlated with urinary calcium during bed rest for the females, but there was no relationship between vegetable protein/potassium intake and bone markers for the males. These data suggest that the ratio of animal protein/potassium intake may affect bone, particularly in bed rest subjects. These data show that the type of protein and gender may be additional factors that modulate the effect of diet on bone metabolism during bed rest. Altering this ratio may help prevent bone loss on Earth and during space flight.

  10. Markers of bone resorption and calcium metabolism are related to dietary intake patterns in male and female bed rest subjects

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.; Zwart, S. R.; Hargens, A. r.

    2006-01-01

    Dietary potassium and protein intakes predict net endogenous acid production in humans. Intracellular buffers, including exchangeable bone mineral, play a crucial role in balancing chronic acid-base perturbations in the body; subsequently, chronic acid loads can potentially contribute to bone loss. Bone is lost during space flight, and a dietary countermeasure would be desirable for many reasons. We studied the ability of diet protein and potassium to predict levels of bone resorption markers in males and females. Identical twin pairs (8 M, 7 F) were assigned to 2 groups: bed rest (sedentary, SED) or bed rest with supine treadmill exercise in a lower body negative pressure chamber (EX). Diet was controlled for 3 d before and 30 d of bed rest (BR). Urinary Ca, N-telopeptide (NTX), and pyridinium crosslinks (PYD) were measured before and on days 5, 12, 19, and 26 of BR. Data were analyzed by Pearson correlation (P<0.05). The ratio of dietary animal protein/potassium intake was not correlated with NTX before BR for males or females, but they were positively correlated in both groups of males during bed rest. Dietary animal protein/potassium and urine Ca were correlated before and during bed rest for the males, and only during bed rest for the females. Conversely, the ratio of dietary vegetable protein/potassium intake was negatively correlated with urinary calcium during bed rest for the females, but there was no relationship between vegetable protein/potassium intake and bone markers for the males. These data suggest that the ratio of animal protein/potassium intake may affect bone, particularly in bed rest subjects. These data show that the type of protein and gender may be additional factors that modulate the effect of diet on bone metabolism during bed rest. Altering this ratio may help prevent bone loss on Earth and during space flight.

  11. 5. American elevator looking east barely visible behind American malt ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. American elevator looking east barely visible behind American malt house with Russell-Miller flour mill to right (now Eonacara and idle). - American Elevator, 87 Childs Street, Buffalo, Erie County, NY

  12. Retrotransposon BARE-1 is a major, dispersed component of the barley (Hordeum vulgare L.) genome.

    PubMed

    Suoniemi, A; Anamthawat-Jónsson, K; Arna, T; Schulman, A H

    1996-03-01

    The barley BARE-1 is a transcribed, copia-like retroelement with well-conserved functional domains, an active promoter, and a copy number of at least 3 x 10(4). We examined its chromosomal localization by in situ hybridization. The long terminal repeat (LTR) probe displayed a uniform hybridization pattern over the whole of all chromosomes, excepting paracentromeric regions, telomeres, and nucleolar organizer (NOR) regions. The integrase probe showed a similar pattern. The 5'-untranslated leader (UTL) probe, expected to be the most rapidly evolving component, labeled chromosomes in a dispersed and non-uniform manner, concentrated in the distal regions, possibly indicating a targe site preference.

  13. Radar Measurement of Water Content Dynamics Over Bare and Vegetated Soil Surfaces

    NASA Astrophysics Data System (ADS)

    Serbin, G.; Or, D.

    2002-12-01

    Recent studies have shown substantial temperature dependence of microwave dielectric properties of soil-water mixtures, which could affect water content inferences from radar backscatter. Soil drying patterns were measured using ground-penetrating radar (GPR) with a 1 GHz center frequency horn antenna that was suspended (> 0.5 m) over bare and vegetated surfaces of soils with different textures. Soil water contents were derived from the surface reflection (SR) amplitudes and the propagation times (PT) to subsurface reflective interfaces. GPR-SR and -PT water content measurements over bare soil surfaces were in good agreement with gravimetric and time domain reflectometry (TDR) measured values. Measurements over vegetated surfaces showed gradual reductions in the maximal values of GPR-SR measured water contents with increase in plant canopy height. In contrast, the maximal value of GPR-PT-derived water content remained unchanged. Aboveground canopy reflections became more pronounced with canopy growth. GPR-SR data showed noticeable diurnal patterns in water contents of bare surfaces. Water content extreme values vary with soil type - for low surface area soils (sand), the maximum occurs at nighttime, whereas for high surface area soils (clay loam) the maximum occurs around midday at normal incidence. An increase in incidence angle caused a shift in measured maxima times to morning hours. These measurements highlight the need for improved understanding of physical effects on dynamics of near-surface radar measurements often used for hydrological studies.

  14. Referral patterns, treatment and outcome of high-grade malignant bone sarcoma in Scandinavia--SSG Central Register 25 years' experience.

    PubMed

    Zaikova, Olga; Sundby Hall, Kirsten; Styring, Emelie; Eriksson, Mikael; Trovik, Clement S; Bergh, Peter; Bjerkehagen, Bodil; Skorpil, Mikael; Weedon-Fekjaer, Harald; Bauer, Henrik C F

    2015-12-01

    The objectives of this study were to present changes in referral patterns, treatment and survival in patients with high-grade malignant bone sarcoma in Sweden and Norway based on data in the Scandinavian Sarcoma Group (SSG) Central Register. Data on 1,437 patients with diagnosis 1986-2010 was analyzed. Osteosarcoma was the most frequentl diagnosis (45%), followed by Ewing sarcoma (21%) and chondrosarcoma (17%). Thirty-one percent of Swedish and 41% of Norwegian patients had tumors in the axial skeleton. Eighty-six percent of extremity tumors and 66% of axial tumors were referred to a sarcoma center prior to unplanned surgery or biopsy. During the past decade, limb salvage surgery has risen from under 50% to over 80%. Five-year overall survival in non-metastatic osteosarcoma was 70% for extremity tumors, and 35% for axial tumors. No improvement in osteosarcoma survival was observed during the last decade. Five-year survival in Ewing sarcoma improved from 50% to 69%. Referral patterns in bone sarcomas have improved. However, greater efforts should be dedicated to improving referral of patients with possible tumors in the axial skeleton to multidisciplinary teams (MDTs). Overall survival of patients with high-grade malignant bone sarcomas in Sweden and Norway is in line with other reports. © 2015 Wiley Periodicals, Inc.

  15. Analysis of Vertebral Bone Strength, Fracture Pattern, and Fracture Location: A Validation Study Using a Computed Tomography-Based Nonlinear Finite Element Analysis

    PubMed Central

    Imai, Kazuhiro

    2015-01-01

    Finite element analysis (FEA) is an advanced computer technique of structural stress analysis developed in engineering mechanics. Because the compressive behavior of vertebral bone shows nonlinear behavior, a nonlinear FEA should be utilized to analyze the clinical vertebral fracture. In this article, a computed tomography-based nonlinear FEA (CT/FEA) to analyze the vertebral bone strength, fracture pattern, and fracture location is introduced. The accuracy of the CT/FEA was validated by performing experimental mechanical testing with human cadaveric specimens. Vertebral bone strength and the minimum principal strain at the vertebral surface were accurately analyzed using the CT/FEA. The experimental fracture pattern and fracture location were also accurately simulated. Optimization of the element size was performed by assessing the accuracy of the CT/FEA, and the optimum element size was assumed to be 2 mm. It is expected that the CT/FEA will be valuable in analyzing vertebral fracture risk and assessing therapeutic effects on osteoporosis. PMID:26029476

  16. Energy Availability and Dietary Patterns of Adult Male and Female Competitive Cyclists With Lower Than Expected Bone Mineral Density.

    PubMed

    Viner, Rebecca T; Harris, Margaret; Berning, Jackie R; Meyer, Nanna L

    2015-12-01

    The purpose of this study was to assess energy availability (EA) and dietary patterns of 10 adult (29-49 years) male (n = 6) and female (n = 4) competitive (USA Cycling Category: Pro, n = 2; 1-4, n = 8) endurance cyclists (5 road, 5 off-road), with lower than expected bone mineral density (BMD; Z score < 0) across a season. Energy intake (EI) and exercise energy expenditure during preseason (PS), competition (C), and off-season (OS) were estimated from 3-day dietary records, completed once per month, across a cycling season. BMD was measured by DXA at 0 months/5 months/10 months. The Three-Factor Eating Questionnaire (TFEQ) was used to assess cognitive dietary restraint. Seventy percent of participants had low EA [(LEA); < 30 kcal · kg fat-free mass (FFM) (-1) · day(-1)] during PS, 90% during C, and 80% during OS (range: 3-37 kcal · kg FFM(-1) · day(-1)). Ninety percent of cyclists had LEA during ≥ 1 training period, and 70% had LEA across the season. Seventy percent of cyclists were identified as restrained eaters who consciously restrict EI as a means of weight control. Mean daily carbohydrate intake was below sport nutrition recommendations during each training period (PS: 3.9 ± 1.1 g · kg(-1) · day(-1), p < .001; C: 4.3 ± 1.4 g · kg(-1) · day(-1), p = .005; OS: 3.7 ± 1.4 g · kg(-1) · day(-1), p = .01). There were no differences in EA and EI · kg(-1) between male and female cyclists and road and off-road cyclists. Low EI, and specifically low carbohydrate intake, appears to be the main contributor to chronic LEA in these cyclists. Adult male and female competitive road and off-road cyclists in the United States may be at risk for long-term LEA. Further studies are needed to explore strategies to prevent and monitor long-term LEA in these athletes.

  17. Killing, letting die and the bare difference argument.

    PubMed

    Perrett, Roy W

    1996-04-01

    I believe that there is no intrinsic moral difference between killing and letting die. That is, there is no difference that depends solely on the distinction between an act and an omission. I also believe that we can reasonably establish this thesis by appeal to the Bare Difference Argument. The form of this argument involves considering two imaginary cases in which there are no morally relevant differences present, save the bare difference that one is a case of killing and one a case of letting die. But in the pair of cases under consideration this bare difference makes no moral difference. Hence it cannot be that the bare difference between killing and letting die is in itself a morally important difference. Winston Nesbitt has recently argued that the Bare Difference Argument fails because "the examples produced typically possess a feature which makes their use in this context illegitimate, and that when modified to remove this feature, they provide support for the view which they were designed to undermine". I argue that Nesbitt misunderstands the logic of the Bare Difference Argument and that accordingly his objections are mistaken.

  18. Differential effects of grammatical gender and gender inflection in bare noun production.

    PubMed

    Paolieri, Daniela; Lotto, Lorella; Leoncini, Debora; Cubelli, Roberto; Job, Remo

    2011-02-01

    In a new series of experiments with the picture-word interference paradigm, we replicated the grammatical gender interference effect in bare noun production in Italian: naming times are slower to picture-word noun pairs sharing the same gender. This effect is independent from the morphological transparency for gender, but responses are significantly slower when the distracters are transparent for gender. Overall, the pattern of results supports the assumption that in bare noun production grammatical gender is always selected, at least in languages like Italian. We assume that the differential effects of the nominal endings are due to the mechanisms involved in the recognition of grammatical gender of the distracter nouns which are sensitive to the morphological transparency for gender: lexical representation of transparent written words leads to a higher level of activation, thus resulting in stronger gender interference. ©2010 The British Psychological Society.

  19. The influence of therapeutic radiation on the patterns of bone marrow in ovary-intact and ovariectomized mice.

    PubMed

    Hui, Susanta K; Sharkey, Leslie; Kidder, Louis S; Zhang, Yan; Fairchild, Greg; Coghill, Kayti; Xian, Cory J; Yee, Douglas

    2012-01-01

    The functional components of bone marrow (i.e., the hematopoietic and stromal populations) and the adjacent bone have traditionally been evaluated incompletely as distinct entities rather than the integrated system. We perturbed this system in vivo using a medically relevant radiation model in the presence or absence of ovarian function to understand integrated tissue interaction. Ovary-intact and ovariectomized mice underwent either no radiation or single fractional 16 Gy radiation to the caudal skeleton (I ± R, OVX ± R). Marrow fat, hematopoietic cellularity, and cancellous bone volume fraction (BV/TV %) were assessed. Ovariectomy alone did not significantly reduce marrow cellularity in non-irradiated mice (OVX-R vs. I-R, p = 0.8445) after 30 days; however it impaired the hematopoietic recovery of marrow following radiation exposure (OVX+R vs. I+R, p = 0.0092). The combination of radiation and OVX dramatically increases marrow fat compared to either factor alone (p = 0.0062). The synergistic effect was also apparent in the reduction of hematopoietic marrow cellularity (p = 0.0661); however it was absent in BV/TV% changes (p = 0.2520). The expected inverse relationship between marrow adiposity vs. hematopoietic cellularity and bone volume was observed. Interestingly compared with OVX mice, intact mice demonstrated double the reduction in hematopoietic cellularity and a tenfold greater degree of bone loss for a given unit of expansion in marrow fat. Ovariectomy prior to delivery of a clinically-relevant focal radiation exposure in mice, exacerbated post-radiation adipose accumulation in the marrow space but blunted bone loss and hematopoietic suppression. In the normally coupled homeostatic relationship between the bone and marrow domains, OVX appears to alter feedback mechanisms. Confirmation of this non-linear phenomenon (presumably due to differential radiosensitivity) and demonstration of the mechanism of action is needed to provide strategies to diminish the

  20. Association between dietary patterns and low bone mineral density among adults aged 50 years and above: findings from the North West Adelaide Health Study (NWAHS).

    PubMed

    Melaku, Yohannes Adama; Gill, Tiffany K; Adams, Robert; Shi, Zumin

    2016-10-01

    Studies on the association between dietary patterns and bone mineral density (BMD) have reported inconsistent findings. Data from the North West Adelaide Health Study, a population-based cohort study undertaken in Australia, were used to assess this association among adults aged 50 years and above. In this specific study, 1182 adults (545 males, 45·9 %) had dietary data collected using a FFQ and also had BMD measurements taken using dual-energy X-ray absorptiometry. Factor analysis with principal component method was applied to ascertain dietary patterns. Two distinct dietary patterns were identified. Pattern 1 ('prudent pattern') was characterised by high intake of fruits, vegetables, sugar, nut-based milk, fish, legumes and high-fibre bread. In contrast, pattern 2 ('Western pattern') was characterised by high levels of processed and red meat, snacks, takeaway foods, jam, beer, soft drinks, white bread, poultry, potato with fat, high-fat dairy products and eggs. Compared with the study participants in the first tertile (T1, lowest consumption) of the prudent pattern, participants in the third tertile (T3) had a lower prevalence of low BMD (prevalence ratio (PR)=0·52; 95 % CI 0·33, 0·83) after adjusting for socio-demographic, lifestyle and behavioural characteristics, chronic conditions and energy intake. Participants in T3 of the Western pattern had a higher prevalence of low BMD (PR=1·68; 95 % CI 1·02, 2·77) compared with those in T1. In contrast to the Western diet, a dietary pattern characterised by high intake of fruits, vegetables and dairy products is positively associated with BMD.

  1. Antlers on the Arctic Refuge: capturing multi-generational patterns of calving ground use from bones on the landscape.

    PubMed

    Miller, Joshua H; Druckenmiller, Patrick; Bahn, Volker

    2013-05-22

    Bone accumulations faithfully record historical ecological data on animal communities, and owing to millennial-scale bone survival on high-latitude landscapes, have exceptional potential for extending records on arctic ecosystems. For the Porcupine Caribou Herd, maintaining access to calving grounds on the Arctic National Wildlife Refuge (ANWR, Alaska) is a central management concern. However, variability in calving ground geography over the 30+ years of monitoring suggests establishing the impacts of climate change and potential petroleum development on future calving success could benefit from extended temporal perspectives. Using accumulations of female antlers (shed within days of calving) and neonatal skeletons, we test if caribou calving grounds develop measureable and characteristic bone accumulations and if skeletal data may be helpful in establishing a fuller, historically integrated understanding of landscape and habitat needs. Bone surveys of an important ANWR calving area reveal abundant shed antlers (reaching 10(3) km(-2)) and high proportional abundance of newborn skeletal individuals (up to 60% neonate). Openly vegetated riparian terraces, which compose less than 10 per cent of ANWR calving grounds, yield significantly higher antler concentrations than more abundant habitats traditionally viewed as primary calving terrain. Differences between habitats appear robust to potential differences in bone visibility. The distribution of antler weathering stages mirrors known multi-decadal calving histories and highlights portions of the antler accumulation that probably significantly extends records of calving activity. Death assemblages offer historically integrated ecological data valuable for the management and conservation of faunas across polar latitudes.

  2. Antlers on the Arctic Refuge: capturing multi-generational patterns of calving ground use from bones on the landscape

    PubMed Central

    Miller, Joshua H.; Druckenmiller, Patrick; Bahn, Volker

    2013-01-01

    Bone accumulations faithfully record historical ecological data on animal communities, and owing to millennial-scale bone survival on high-latitude landscapes, have exceptional potential for extending records on arctic ecosystems. For the Porcupine Caribou Herd, maintaining access to calving grounds on the Arctic National Wildlife Refuge (ANWR, Alaska) is a central management concern. However, variability in calving ground geography over the 30+ years of monitoring suggests establishing the impacts of climate change and potential petroleum development on future calving success could benefit from extended temporal perspectives. Using accumulations of female antlers (shed within days of calving) and neonatal skeletons, we test if caribou calving grounds develop measureable and characteristic bone accumulations and if skeletal data may be helpful in establishing a fuller, historically integrated understanding of landscape and habitat needs. Bone surveys of an important ANWR calving area reveal abundant shed antlers (reaching 103 km–2) and high proportional abundance of newborn skeletal individuals (up to 60% neonate). Openly vegetated riparian terraces, which compose less than 10 per cent of ANWR calving grounds, yield significantly higher antler concentrations than more abundant habitats traditionally viewed as primary calving terrain. Differences between habitats appear robust to potential differences in bone visibility. The distribution of antler weathering stages mirrors known multi-decadal calving histories and highlights portions of the antler accumulation that probably significantly extends records of calving activity. Death assemblages offer historically integrated ecological data valuable for the management and conservation of faunas across polar latitudes. PMID:23536601

  3. High levels of periostin correlate with increased fracture rate, diffuse MRI pattern, abnormal bone remodeling and advanced disease stage in patients with newly diagnosed symptomatic multiple myeloma

    PubMed Central

    Terpos, E; Christoulas, D; Kastritis, E; Bagratuni, T; Gavriatopoulou, M; Roussou, M; Papatheodorou, A; Eleutherakis-Papaiakovou, E; Kanellias, N; Liakou, C; Panagiotidis, I; Migkou, M; Kokkoris, P; Moulopoulos, L A; Dimopoulos, M A

    2016-01-01

    Periostin is an extracellular matrix protein that is implicated in the biology of normal bone remodeling and in different cancer cell growth and metastasis. However, there is no information on the role of periostin in multiple myeloma (MM). Thus, we evaluated periostin in six myeloma cell lines in vitro; in the bone marrow plasma and serum of 105 newly diagnosed symptomatic MM (NDMM) patients and in the serum of 23 monoclonal gammopathy of undetermined significance (MGUS), 33 smoldering MM (SMM) patients, 30 patients at the plateau phase post-first-line therapy, 30 patients at first relapse and 30 healthy controls. We found high levels of periostin in the supernatants of myeloma cell lines compared with ovarian cancer cell lines that were not influenced by the incubation with the stromal cell line HS5. In NDMM patients the bone marrow plasma periostin was almost fourfold higher compared with the serum levels of periostin and correlated with the presence of fractures and of diffuse magnetic resonance imaging pattern of marrow infiltration. Serum periostin was elevated in NDMM patients compared with healthy controls, MGUS and SMM patients and correlated with advanced disease stage, high lactate dehydrogenase, increased activin-A, increased bone resorption and reduced bone formation. Patients at first relapse had also elevated periostin compared with healthy controls, MGUS and SMM patients, while even patients at the plateau phase had elevated serum periostin compared with healthy controls. These results support an important role of periostin in the biology of myeloma and reveal periostin as a possible target for the development of antimyeloma drugs. PMID:27716740

  4. A Western Diet Pattern Is Associated with Higher Concentrations of Blood and Bone Lead among Middle-Aged and Elderly Men.

    PubMed

    Wang, Xin; Ding, Ning; Tucker, Katherine L; Weisskopf, Marc G; Sparrow, David; Hu, Howard; Park, Sung Kyun

    2017-07-01

    Background: Little is known about the effects of overall dietary pattern on lead concentration.Objective: We examined the association of overall dietary patterns, derived from a semiquantitative food frequency questionnaire, with bone and blood lead concentrations.Methods: These longitudinal analyses included mostly non-Hispanic white, middle-aged-to-elderly men from the Veterans Affairs Normative Aging Study. Long-term lead exposures were measured as tibia and patella lead concentrations by using K-shell-X-ray fluorescence. Short-term lead exposures were measured as blood lead concentrations by using graphite furnace atomic absorption spectroscopy. Dietary pattern scores were derived by using factor analysis. Linear mixed-effects models were utilized to predict blood lead concentrations among 983 men, aged 44-92 y at baseline, with a total of 3273 observations (during 1987-2008). We constructed linear regression models to determine the relations between dietary patterns and bone lead concentrations among 649 participants with an age range of 49-93 y.Results: Two major dietary patterns were identified: a prudent dietary pattern, characterized by high intakes of fruit, legumes, vegetables, whole grains, poultry, and seafood; and a Western dietary pattern, characterized by high intakes of processed meat, red meat, refined grains, high-fat dairy products, French fries, butter, and eggs. After adjusting for age, smoking status, body mass index, total energy intake, education, occupation, neighborhood-based education and income level, men in the highest tertile of the Western pattern score (compared with the lowest) had 0.91 μg/dL (95% CI: 0.41, 1.42 μg/dL) higher blood lead, 5.96 μg/g (95% CI: 1.76, 10.16 μg/g) higher patella lead, and 3.83 μg/g (95% CI: 0.97, 6.70 μg/g) higher tibia lead. No significant association was detected with the prudent dietary pattern in the adjusted model.Conclusions: These findings suggest that the Western diet is associated with a

  5. In vivo bone strain patterns in the zygomatic arch of macaques and the significance of these patterns for functional interpretations of craniofacial form.

    PubMed

    Hylander, W L; Johnson, K R

    1997-02-01

    It has been proposed that the mammalian facial skeleton is optimized for countering or dissipating masticatory stress. As optimized load-bearing structures by definition exhibit maximum strength with a minimum amount of material, this hypothesis predicts that during chewing and biting there should be relatively high and near uniform amounts of strain throughout the facial skeleton. If levels of strain in certain areas of the facial skeleton are relatively low during these behaviors, this indicates that the amount of bone mass in these areas could be significantly reduced without resulting in the danger of structural failure due to repeated masticatory loads. Furthermore, and by definition, this indicates that these areas are not optimized for countering masticatory stress, and instead their overall morphology and concentration of bone mass has most likely been selected or influenced mainly by factors unrelated to the dissipation or countering of chewing and biting forces. An analysis of in vivo bone strain along the lateral aspect of the zygomatic arch of macaques indicates the clear absence of a high and near uniform strain environment throughout its extent. Instead, there is a steep strain gradient along the zygomatic arch, with the highest strains along its anterior portion, intermediate strains along its middle portion, and the lowest strains along its posterior portion. These data, in combination with earlier published data (Hylander et al., 1991), indicate that levels of functional strains during chewing and biting are highly variable from one region of the face to the next, and therefore it is unlikely that all facial bones are especially designed so as to minimize bone tissue and maximize strength for countering masticatory loads. Thus, the functional significance of the morphology of certain facial bones need not necessarily bear any important or special relationship to routine and habitual cyclical mechanical loads associated with chewing or biting

  6. Bone trace element pattern in an 18th century population sample of Tenerife (Canary Islands): comparison with a prehistoric one.

    PubMed

    Arnay-de-la-Rosa, M; Gonzalez-Reimers, E; Velasco-Vazquez, J; Barros-Lopez, N; Galindo-Martin, L

    1998-10-01

    We have determined bone strontium (Sr), barium (Ba), calcium (Ca), and zinc (Zn) content in 24 samples belonging to adult individuals who died toward the end of the 18th century and were interred in a church's floor on the island of Tenerife, comparing the results with those obtained in 14 prehistoric samples of the same island and also with those of 7 modern controls. No differences were observed between the two ancient groups, which showed higher bone strontium and barium than the modern sample, and a slightly lower Ba/Sr ratio, thus pointing to consumption of marine sources.

  7. The frequency of osteogenic activities and the pattern of intermittence between periods of physical activity and sedentary behaviour affects bone mineral content: the cross-sectional NHANES study.

    PubMed

    Chastin, Sebastien Fm; Mandrichenko, Oleksii; Skelton, Dawn A

    2014-01-06

    Sedentary behaviours, defined as non exercising seated activities, have been shown to have deleterious effects on health. It has been hypothesised that too much sitting time can have a detrimental effect on bone health in youth. The aim of this study is to test this hypothesis by exploring the association between objectively measured volume and patterns of time spent in sedentary behaviours, time spent in specific screen-based sedentary pursuits and bone mineral content (BMC) accrual in youth. NHANES 2005-2006 cycle data includes BMC of the femoral and spinal region via dual-energy X-ray absorptiometry (DEXA), assessment of physical activity and sedentary behaviour patterns through accelerometry, self reported time spent in screen based pursuits (watching TV and using a computer), and frequency of vigorous playtime and strengthening activities. Multiple regression analysis, stratified by gender was performed on N = 671 males and N = 677 females aged from 8 to 22 years. Time spent in screen-based sedentary behaviours is negatively associated with femoral BMC (males and females) and spinal BMC (females only) after correction for time spent in moderate and vigorous activity. Regression coefficients indicate that an additional hour per day of screen-based sitting corresponds to a difference of -0.77 g femoral BMC in females [95% CI: -1.31 to -0.22] and of -0.45 g femoral BMC in males [95% CI: -0.83 to -0.06]. This association is attenuated when self-reported engagement in regular (average 5 times per week) strengthening exercise (for males) and vigorous playing (for both males and females) is taken into account. Total sitting time and non screen-based sitting do not appear to have a negative association with BMC, whereas screen based sedentary time does. Patterns of intermittence between periods of sitting and moderate to vigorous activity appears to be positively associated with bone health when activity is clustered in time and inter-spaced with long

  8. Giant Cell Tumor with Secondary Aneurysmal Bone Cyst Shows Heterogeneous Metabolic Pattern on (18)F-FDG PET/CT: A Case Report.

    PubMed

    Park, Hee Jeong; Kwon, Seong Young; Cho, Sang-Geon; Kim, Jahae; Song, Ho-Chun; Kim, Sung Sun; Yoon, Yeon Hong; Park, Jin Gyoon

    2016-12-01

    Giant cell tumor (GCT) is a generally benign bone tumor accounting for approximately 5 % of all primary bone neoplasms. Cystic components in GCTs that indicate secondary aneurysmal bone cysts (ABCs) are reported in 14 % of GCTs. Although both of them have been described separately in previous reports that may show considerable fluorodeoxyglucose (FDG) uptake despite their benign nature, the findings of GCT with secondary ABC on (18)F-FDG positron emission tomography/computed tomography (PET/CT) have not been well-known. We report a case of GCT with secondary ABC in a 26-year-old woman. (18)F-FDG PET/CT revealed a heterogeneous hypermetabolic lesion in the left proximal femur with the maximum standardized uptake value of 4.7. The solid components of the tumor showed higher FDG uptake than the cystic components. These observations suggest that the ABC components in GCTs show heterogeneous metabolic patterns on (18)F-FDG PET/CT.

  9. Gene Deletion in Barley Mediated by LTR-retrotransposon BARE

    PubMed Central

    Shang, Yi; Yang, Fei; Schulman, Alan H.; Zhu, Jinghuan; Jia, Yong; Wang, Junmei; Zhang, Xiao-Qi; Jia, Qiaojun; Hua, Wei; Yang, Jianming; Li, Chengdao

    2017-01-01

    A poly-row branched spike (prbs) barley mutant was obtained from soaking a two-rowed barley inflorescence in a solution of maize genomic DNA. Positional cloning and sequencing demonstrated that the prbs mutant resulted from a 28 kb deletion including the inflorescence architecture gene HvRA2. Sequence annotation revealed that the HvRA2 gene is flanked by two LTR (long terminal repeat) retrotransposons (BARE) sharing 89% sequence identity. A recombination between the integrase (IN) gene regions of the two BARE copies resulted in the formation of an intact BARE and loss of HvRA2. No maize DNA was detected in the recombination region although the flanking sequences of HvRA2 gene showed over 73% of sequence identity with repetitive sequences on 10 maize chromosomes. It is still unknown whether the interaction of retrotransposons between barley and maize has resulted in the recombination observed in the present study. PMID:28252053

  10. Novel 3D scaffold with enhanced physical and cell response properties for bone tissue regeneration, fabricated by patterned electrospinning/electrospraying.

    PubMed

    Hejazi, Fatemeh; Mirzadeh, Hamid

    2016-09-01

    Developing three dimensional scaffolds mimicking the nanoscale structure of native extracellular matrix is a key parameter in tissue regeneration. In this study, we aimed to introduce a novel 3D structures composed of nanofibers (NF) and micro particles (MP) and compare their efficiency with 2D nanofibrous scaffold. The conventional nanofibrous PCL scaffolds are 2D mats fabricated by the electrospinning technique, whereas the NF/MP and patterned NF/MP PCL scaffolds are three dimensional structures fabricated by a modified electrospinning/electrospraying technique. The mentioned method was carried out by varying the electrospinning solution parameters and use of a metal mesh as the collector. Detailed fabrication process and morphological properties of the fabricated structures is discussed and porosity, pore size and PBS solution absorption value of the prepared structures are reported. Compared with the 2D structure, 3D scaffolds possessed enhanced porosity and pore size which led to the significant increase in their water uptake capacity. In vitro cell experiments were carried out on the prepared structures by the use of MG-63 osteosarcoma cell line. The fabricated 3D structures offered significantly increased cell attachment, spread and diffusion which were confirmed by SEM analysis. In vitro cytocompatibility assessed by MTT colorimetric assay indicated a continuous cell proliferation over 21 days on the innovative 3D structure, while on 2D mat cell proliferation stopped at early time points. Enhanced osteogenic differentiation of the seeded MG-63 cells on 3D scaffold was confirmed by the remarkable ALP activity together with increased and accelerated calcium deposition on this structure compared to 2D mat. Massive and well distributed bone minerals formed on patterned 3D structure were shown by EDX analysis. In comparison between NF/MP quasi-3D and Patterned NF/MP 3D scaffolds, patterned structures proceeded in all of the above properties. As such, the

  11. Development of a 'bare-earth' SRTM DEM product

    NASA Astrophysics Data System (ADS)

    O'Loughlin, Fiachra; Paiva, Rodrigo; Durand, Michael; Alsdorf, Douglas; Bates, Paul

    2015-04-01

    We present the methodology and results from the development of a near-global 'bare-earth' Digital Elevation Model (DEM) derived from the Shuttle Radar Topography Mission (SRTM) data. Digital Elevation Models are the most important input for hydraulic modelling, as the DEM quality governs the accuracy of the model outputs. While SRTM is currently the best near-globally [60N to 60S] available DEM, it requires adjustments to reduce the vegetation contamination and make it useful for hydrodynamic modelling over heavily vegetated areas (e.g. tropical wetlands). Unlike previous methods of accounting for vegetation contamination, which concentrated on correcting relatively small areas and usually applied a static adjustment, we account for vegetation contamination globally and apply a spatial varying correction, based on information about canopy height and density. In creating the final 'bare-earth' SRTM DEM dataset, we produced three different 'bare-earth' SRTM products. The first applies global parameters, while the second and third products apply parameters that are regionalised based on either climatic zones or vegetation types, respectively. We also tested two different canopy density proxies of different spatial resolution. Using ground elevations obtained from the ICESat GLA14 satellite altimeter, we calculate the residual errors for the raw SRTM and the three 'bare-earth' SRTM products and compare performances. The three 'bare-earth' products all show large improvements over the raw SRTM in vegetated areas with the overall mean bias reduced by between 75 and 92% from 4.94 m to 0.40 m. The overall standard deviation is reduced by between 29 and 33 % from 7.12 m to 4.80 m. As expected, improvements are higher in areas with denser vegetation. The final 'bare-earth' SRTM dataset is available at 3 arc-second with lower vertical height errors and less noise than the original SRTM product.

  12. A Management Information System for Bare Base Civil Engineering Commanders

    DTIC Science & Technology

    1988-09-01

    initial beddown stage. The purpose of this research was to determine the feasibility of developing a microcomputer based management information system (MIS...the software best suited to synthesize four of the categories into a prototype field MIS. Keyword: Management information system , Bare bases, Civil engineering, Data bases, Information retrieval.

  13. 30 CFR 57.12012 - Bare signal wires.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Bare signal wires. 57.12012 Section 57.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface...

  14. 30 CFR 56.12012 - Bare signal wires.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare signal wires. 56.12012 Section 56.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12012...

  15. 30 CFR 56.12012 - Bare signal wires.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Bare signal wires. 56.12012 Section 56.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12012...

  16. 30 CFR 56.12012 - Bare signal wires.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Bare signal wires. 56.12012 Section 56.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12012...

  17. 30 CFR 57.12012 - Bare signal wires.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Bare signal wires. 57.12012 Section 57.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface...

  18. 30 CFR 56.12012 - Bare signal wires.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Bare signal wires. 56.12012 Section 56.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12012...

  19. 30 CFR 56.12012 - Bare signal wires.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Bare signal wires. 56.12012 Section 56.12012 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12012...

  20. BARE Retrotransposons Are Translated and Replicated via Distinct RNA Pools

    PubMed Central

    Chang, Wei; Jääskeläinen, Marko; Li, Song-ping; Schulman, Alan H.

    2013-01-01

    The replication of Long Terminal Repeat (LTR) retrotransposons, which can constitute over 80% of higher plant genomes, resembles that of retroviruses. A major question for retrotransposons and retroviruses is how the two conflicting roles of their transcripts, in translation and reverse transcription, are balanced. Here, we show that the BARE retrotransposon, despite its organization into just one open reading frame, produces three distinct classes of transcripts. One is capped, polyadenylated, and translated, but cannot be copied into cDNA. The second is not capped or polyadenylated, but is destined for packaging and ultimate reverse transcription. The third class is capped, polyadenylated, and spliced to favor production of a subgenomic RNA encoding only Gag, the protein forming virus-like particles. Moreover, the BARE2 subfamily, which cannot synthesize Gag and is parasitic on BARE1, does not produce the spliced sub-genomic RNA for translation but does make the replication competent transcripts, which are packaged into BARE1 particles. To our knowledge, this is first demonstration of distinct RNA pools for translation and transcription for any retrotransposon. PMID:23940808

  1. Dietary patterns in Canadian men and women ages 25 and older: relationship to demographics, body mass index, and bone mineral density

    PubMed Central

    2010-01-01

    Background Previous research has shown that underlying dietary patterns are related to the risk of many different adverse health outcomes, but the relationship of these underlying patterns to skeletal fragility is not well understood. The objective of the study was to determine whether dietary patterns in men (ages 25-49, 50+) and women (pre-menopause, post-menopause) are related to femoral neck bone mineral density (BMD) independently of other lifestyle variables, and whether this relationship is mediated by body mass index. Methods We performed an analysis of 1928 men and 4611 women participants in the Canadian Multicentre Osteoporosis Study, a randomly selected population-based longitudinal cohort. We determined dietary patterns based on the self-administered food frequency questionnaires in year 2 of the study (1997-99). Our primary outcome was BMD as measured by dual x-ray absorptiometry in year 5 of the study (2000-02). Results We identified two underlying dietary patterns using factor analysis and then derived factor scores. The first factor (nutrient dense) was most strongly associated with intake of fruits, vegetables, and whole grains. The second factor (energy dense) was most strongly associated with intake of soft drinks, potato chips and French fries, certain meats (hamburger, hot dog, lunch meat, bacon, and sausage), and certain desserts (doughnuts, chocolate, ice cream). The energy dense factor was associated with higher body mass index independent of other demographic and lifestyle factors, and body mass index was a strong independent predictor of BMD. Surprisingly, we did not find a similar positive association between diet and BMD. In fact, when adjusted for body mass index, each standard deviation increase in the energy dense score was associated with a BMD decrease of 0.009 (95% CI: 0.002, 0.016) g/cm2 for men 50+ years old and 0.004 (95% CI: 0.000, 0.008) g/cm2 for postmenopausal women. In contrast, for men 25-49 years old, each standard

  2. Evaluation of Bare Ground on Rangelands using Unmanned Aerial Vehicles

    SciTech Connect

    Robert P. Breckenridge; Maxine Dakins

    2011-01-01

    Attention is currently being given to methods that assess the ecological condition of rangelands throughout the United States. There are a number of different indicators that assess ecological condition of rangelands. Bare Ground is being considered by a number of agencies and resource specialists as a lead indicator that can be evaluated over a broad area. Traditional methods of measuring bare ground rely on field technicians collecting data along a line transect or from a plot. Unmanned aerial vehicles (UAVs) provide an alternative to collecting field data, can monitor a large area in a relative short period of time, and in many cases can enhance safety and time required to collect data. In this study, both fixed wing and helicopter UAVs were used to measure bare ground in a sagebrush steppe ecosystem. The data were collected with digital imagery and read using the image analysis software SamplePoint. The approach was tested over seven different plots and compared against traditional field methods to evaluate accuracy for assessing bare ground. The field plots were located on the Idaho National Laboratory (INL) site west of Idaho Falls, Idaho in locations where there is very little disturbance by humans and the area is grazed only by wildlife. The comparison of fixed-wing and helicopter UAV technology against field estimates shows good agreement for the measurement of bare ground. This study shows that if a high degree of detail and data accuracy is desired, then a helicopter UAV may be a good platform. If the data collection objective is to assess broad-scale landscape level changes, then the collection of imagery with a fixed-wing system is probably more appropriate.

  3. Immunohistochemical study of Ulex europaeus agglutinin 1 (UEA-1) binding of megakaryocytes in bone marrow biopsy specimens: demonstration of heterogeneity in staining pattern reflecting the stages of differentiation.

    PubMed

    Liu, S M; Li, C Y

    1996-01-01

    During differentiation, megakaryocytes undergo nuclear endoreplication, an increase in cell size, cytoplasmic granulation, and release of platelets. The changes in highly lobulated nuclei with varying degree of polyploidy and increasing cell size are easily recognized morphologically. However, the actual cytoplasmic changes are more difficult to perceive morphologically. With the peroxidase-antiperoxidase (PAP) method using UEA-1 as the binding protein to the alpha-L-fucose of glycoprotein synthesized by megakaryocytes, we observed significant variation in cytoplasmic staining of megakaryocytes in routinely processed bone marrow biopsy sections. A total of 3344 megakaryocytes in bone marrow sections from 10 patients with nonhematologic diseases and from 10 patients with idiopathic thrombocytopenic purpura (ITP) was studied. According to the intensity and pattern of cytoplasmic staining, we divided megakaryocytes into at least six groups: (1) low granular (LG), (2) diffuse granular (DG), (3) diffuse dense granular (DDG), (4) marginal granular (MG), (5) denuded (DMK), and (6) endomitotic (EndoM). Most of the megakaryocytes were DG (mean, 42.75% +/- 19.21%) and DDG (mean, 50.25% +/- 21.23%). In correlation with nuclear morphology and cell size, it appears that substances binding to UEA-1 are located in the paranuclear region in early megakaryocytes and produce a low granular focal staining pattern (LG cells). Next, the granules spread throughout the cytoplasm (DG cells) and increase in quantity (DDG). This is followed by migration of granules to the periphery of the cytoplasm (MG cells) and is associated with the liberation of platelets and eventual formation of DMK megakaryocytes. Endomitosis, regulated by unknown factors, occurred in the MG stage. In comparing the group with nonhematologic disease (mean DG, 35.4% +/- 18.48%; DDG, 58.4% +/- 21.8%) and the group with ITP (mean DG, 50.1% +/- 17.82%; DDG, 42.1% +/- 18.12%), we found an increasing proportion of DG

  4. Bone densitometric assessment and management of fracture risk in Indian men of prostate cancer on androgen deprivation therapy: Does practice pattern match the guidelines?

    PubMed Central

    Pradhan, Manas R.; Mandhani, Anil; Chipde, Saurabh S.; Srivastava, Alok; Singh, Manmeet; Kapoor, Rakesh

    2012-01-01

    Objective: Estimation of baseline bone mineral density (BMD) at the time of instituting androgen deprivation therapy (ADT) for metastatic prostate cancer is recommended by several specialty groups and expert panels. The present study was carried out to analyze the practice pattern of Indian urologists with regard to bone densitometric assessment and management of fracture risk in men of prostate cancer on ADT, and their degree of adherence to currently available guidelines Materials and Methods: Telephonic interviews of 108 qualified urologists, randomly selected from the member database of Urological Society of India was carried out with a predefined questionnaire. The responses were analyzed and compared with the available evidences and recommendations. Results: Only 19.4% urologists routinely perform a baseline BMD before starting ADT. Although majority of them prescribe calcium and vitamin D supplementation, only few tell regarding fracture risk and life-style modification to their patients. While 59.6% of the respondents use Zoledronic acid (ZA) in their patients on ADT, half of them prescribe it without knowing the BMD status, which may lead to overuse of ZA. Conclusion: Majority of the urologists in India do not follow the guidelines for BMD measurement in prostate cancer. A baseline BMD may help in reducing the unnecessary use of ZA. PMID:23450674

  5. Bone Diseases

    MedlinePlus

    ... avoid smoking and drinking too much alcohol. Bone diseases can make bones easy to break. Different kinds ... break Osteogenesis imperfecta makes your bones brittle Paget's disease of bone makes them weak Bones can also ...

  6. Genetic Variation in the Patterns of Skeletal Progenitor Cell Differentiation and Progression During Endochondral Bone Formation Affects the Rate of Fracture Healing

    PubMed Central

    Jepsen, Karl J; Price, Christopher; Silkman, Lee J; Nicholls, Fred H; Nasser, Phillip; Hu, Bin; Hadi, Nicole; Alapatt, Michael; Stapleton, Stephanie N; Kakar, Sanjeev; Einhorn, Thomas A; Gerstenfeld, Louis C

    2008-01-01

    These studies examined how genetic differences that regulate architectural and bone material properties would be expressed during fracture healing and determine whether any of these features would affect rates of healing as defined by regain of strength. Controlled fractures were generated in three inbred strains of mice: A/J, C57Bl/6J (B6), and C3H/HeJ (C3H). Both the A/J and B6 strains showed faster healing than the C3H strain based on regains in strength and stiffness. Strain-specific architectural features such as moment of inertia, cross-sectional area, and cortical thickness were all recapitulated during the development of the callus tissues. None of these traits were directly relatable to rates of fracture healing. However, rates of healing were related to variations in the temporal patterns of chondrogenic and osteogenic lineage development. The B6 strain expressed the highest percentage of cartilage gene products and had the longest period of chondrocyte maturation and hypertrophy. The slowest healing strain (C3H) had the shortest period of chondrogenic development and earliest initiation of osteogenic development. Although the A/J strain showed an almost identical pattern of chondrogenic development as the C3H strain, A/J initiated osteogenic development several days later than C3H during fracture healing. Long bone growth plates at 28 days after birth showed similar strain-specific variation in cartilage tissue development as seen in fracture healing. Thus, the B6 strain had the largest growth plate heights, cell numbers per column, and the largest cell size, whereas the C3H columns were the shortest, had the smallest number of cells per column, and showed the smallest cell sizes. These results show that (1) different strains of mice express variations of skeletal stem cell lineage differentiation and (2) that these variations affect the rate of fracture healing. PMID:18348700

  7. Assembling Bare Au Nanoparticles at Positively Charged Templates

    SciTech Connect

    Wang, Wenjie; Zhang, Honghu; Kuzmenko, Ivan; Mallapragada, Surya; Vaknin, David

    2016-05-26

    In-situ X-ray reflectivity (XRR) and grazing incidence X-ray small-angle scattering (GISAXS) reveal that unfunctionalized (bare) gold nanoparticles (AuNP) spontaneously adsorb to a cationic lipid template formed by a Langmuir monolayer of DPTAP (1,2-dihexadecanoyl-3-trimethylammonium-propane) at vapor/aqueous interfaces. Analysis of the XRR yields the electron density profile across the charged-interfaces along the surface normal showing the AuNPs assemble with vertical thickness comparable to the particle size. The GISAXS analysis indicates that the adsorbed mono-particle layer exhibits short-range in-plane correlations. By contrast, single-stranded DNA-functionalized AuNPs, while attracted to the positively charged surface (more efficiently with the addition of salt to the solution), display less in-plane regular packing compared to bare AuNPs.

  8. Assembling Bare Au Nanoparticles at Positively Charged Templates

    DOE PAGES

    Wang, Wenjie; Zhang, Honghu; Kuzmenko, Ivan; ...

    2016-05-26

    In-situ X-ray reflectivity (XRR) and grazing incidence X-ray small-angle scattering (GISAXS) reveal that unfunctionalized (bare) gold nanoparticles (AuNP) spontaneously adsorb to a cationic lipid template formed by a Langmuir monolayer of DPTAP (1,2-dihexadecanoyl-3-trimethylammonium-propane) at vapor/aqueous interfaces. Analysis of the XRR yields the electron density profile across the charged-interfaces along the surface normal showing the AuNPs assemble with vertical thickness comparable to the particle size. The GISAXS analysis indicates that the adsorbed mono-particle layer exhibits short-range in-plane correlations. By contrast, single-stranded DNA-functionalized AuNPs, while attracted to the positively charged surface (more efficiently with the addition of salt to the solution), displaymore » less in-plane regular packing compared to bare AuNPs.« less

  9. Assembling Bare Au Nanoparticles at Positively Charged Templates

    PubMed Central

    Wang, Wenjie; Zhang, Honghu; Kuzmenko, Ivan; Mallapragada, Surya; Vaknin, David

    2016-01-01

    In-situ X-ray reflectivity (XRR) and grazing incidence X-ray small-angle scattering (GISAXS) reveal that unfunctionalized (bare) gold nanoparticles (AuNP) spontaneously adsorb to a cationic lipid template formed by a Langmuir monolayer of DPTAP (1,2-dihexadecanoyl-3-trimethylammonium-propane) at vapor/aqueous interfaces. Analysis of the XRR yields the electron density profile across the charged-interfaces along the surface normal showing the AuNPs assemble with vertical thickness comparable to the particle size. The GISAXS analysis indicates that the adsorbed mono-particle layer exhibits short-range in-plane correlations. By contrast, single-stranded DNA-functionalized AuNPs, while attracted to the positively charged surface (more efficiently with the addition of salt to the solution), display less in-plane regular packing compared to bare AuNPs. PMID:27225047

  10. Assembling Bare Au Nanoparticles at Positively Charged Templates

    SciTech Connect

    Wang, Wenjie; Zhang, Honghu; Kuzmenko, Ivan; Mallapragada, Surya; Vaknin, David

    2016-05-26

    In-situ X-ray reflectivity (XRR) and grazing incidence X-ray small-angle scattering (GISAXS) reveal that unfunctionalized (bare) gold nanoparticles (AuNP) spontaneously adsorb to a cationic lipid template formed by a Langmuir monolayer of DPTAP (1,2-dihexadecanoyl-3-trimethylammonium-propane) at vapor/aqueous interfaces. Analysis of the XRR yields the electron density profile across the chargedinterfaces along the surface normal showing the AuNPs assemble with vertical thickness comparable to the particle size. The GISAXS analysis indicates that the adsorbed mono-particle layer exhibits shortrange in-plane correlations. By contrast, single-stranded DNA-functionalized AuNPs, while attracted to the positively charged surface (more efficiently with the addition of salt to the solution), display less in-plane regular packing compared to bare AuNPs.

  11. Terrain classification of ladar data for bare earth determination

    NASA Astrophysics Data System (ADS)

    Neuenschwander, Amy L.; Magruder, Lori A.

    2011-06-01

    Terrain classification, or bare earth extraction, is an important component to LADAR data analysis. The terrain classification approach presented in this effort utilizes an adaptive lower envelope follower (ALEF) with an adaptive gradient operation for accommodations of local topography and roughness. In order to create a more robust capability, the ALEF was modified to become a strictly data driven process that facilitates a quick production of the data product without the subjective component associated with user inputs. This automated technique was tested on existing LADAR surveys over Wyoming's Powder River Basin and the John Starr Memorial Forest in Mississippi, both locations with dynamic topographic features. The results indicate a useful approach in terms of operational time and accuracy of the final bare earth recovery with the advantage of being fully data driven.

  12. Bare and Effective Charge of Mesoporous Silica Particles.

    PubMed

    Valetti, Sabrina; Feiler, Adam; Trulsson, Martin

    2017-07-25

    We develop and combine a novel numerical model, within the Poisson-Boltzmann framework, with classical experimental titration techniques for mesoporous silica particles to study the charging behavior as both pH and the amount of monovalent salt are varied. One key finding is that these particles can be considered to have an effectively or apparent electroneutral inner core with an effectively charged rim. As a consequence, the total apparent charge of the particle is several orders of magnitude smaller than that of the bare silica charge, which accounts only for the charged silanol groups of the mesoporous silica particles and which has its major contribution from the interior. Hence, the interior dictates the mesoporous silicas' bare charge while the rim its effective charge. We furthermore report density, charge, and accumulated charge profiles across the particle's interface.

  13. Thermal evolution and light curves of young bare strange stars.

    PubMed

    Page, Dany; Usov, Vladimir V

    2002-09-23

    We study numerically the cooling of a young bare strange star and show that its thermal luminosity, mostly due to e(+)e(-) pair production from the quark surface, may be much higher than the Eddington limit. The mean energy of photons far from the strange star is approximately 10(2) keV or even more. This differs both qualitatively and quantitatively from the thermal emission from neutron stars and provides a definite observational signature for bare strange stars. It is shown that the energy gap of superconducting quark matter may be estimated from the light curves if it is in the range from approximately 0.5 MeV to a few MeV.

  14. Assembling Bare Au Nanoparticles at Positively Charged Templates

    NASA Astrophysics Data System (ADS)

    Wang, Wenjie; Zhang, Honghu; Kuzmenko, Ivan; Mallapragada, Surya; Vaknin, David

    2016-05-01

    In-situ X-ray reflectivity (XRR) and grazing incidence X-ray small-angle scattering (GISAXS) reveal that unfunctionalized (bare) gold nanoparticles (AuNP) spontaneously adsorb to a cationic lipid template formed by a Langmuir monolayer of DPTAP (1,2-dihexadecanoyl-3-trimethylammonium-propane) at vapor/aqueous interfaces. Analysis of the XRR yields the electron density profile across the charged-interfaces along the surface normal showing the AuNPs assemble with vertical thickness comparable to the particle size. The GISAXS analysis indicates that the adsorbed mono-particle layer exhibits short-range in-plane correlations. By contrast, single-stranded DNA-functionalized AuNPs, while attracted to the positively charged surface (more efficiently with the addition of salt to the solution), display less in-plane regular packing compared to bare AuNPs.

  15. Different patterns of global and regional skeletal uptake of 99mTc-methylene diphosphonate with age: relevance to the pathogenesis of bone loss.

    PubMed

    Carnevale, V; Dicembrino, F; Frusciante, V; Chiodini, I; Minisola, S; Scillitani, A

    2000-09-01

    Bone turnover changes with age have been shown by both histomorphometric and scintimetric methods; fewer studies have been performed on the regional differences of bone remodeling in the aging skeleton. To noninvasively investigate this issue, we evaluated the age-related patterns of global and regional bone uptake of 99mTc-methylene diphosphonate (MDP) in a large sample of healthy women. In a group of 84 healthy women (33 pre- and 51 postmenopausal), the uptake of 99mTcMDP was semiquantitatively measured in 5 regions of interest. Total-body digital scans (TBDSs) were acquired at 5 min and at 4 h. Five regions of interest were drawn on the skeleton as a whole, on the lumbar spine, on the iliac wing, on the femoral neck, and on the femoral diaphysis of the 4-h TBDS. Regional skeletal uptake of the lumbar spine (LS-RSU), of the iliac wing (IL-RSU), of the femoral neck (FN-RSU), and of the femoral diaphysis (FD-RSU) was calculated as percentage injected dose retained in these skeletal segments at 4 h. As expected, in postmenopausal women the global skeletal uptake (GSU) values were higher than those in premenopausal women (40.7 +/- 5.9 percentage injected dose [%ID] versus 35.1 +/- 4.2 %ID; P < 0.0001). GSU correlated positively with age (r = 0.70; P < 0.001), but the addition of years since menopause to the regression model did not ameliorate the regression. On the other hand, LS-RSU (r = -0.55; P < 0.0001), IL-RSU (r = -0.45; P < 0.0001), and FN-RSU (r = -0.22; P < 0.005) decreased significantly, whereas FD-RSU increased significantly (r = 0.39; P < 0.001) with age; the same regressions were not influenced significantly by the addition of menopausal duration to the regression model. The strongest correlation among the different RSUs was that found between LS-RSU and IL-RSU (r = 0.63; P < 0.001). Moreover, the linear regression coefficients of the various RSUs with age were all significantly different from each other (P < 0.001). Our data show that the GSU of 99m

  16. Next Generation Bare Base Waste Processing System (Phase 1)

    DTIC Science & Technology

    1997-08-01

    Municipal Solid Waste Generation in the United States in 1994 ............. 10 Table 5.3.1.2 Estimated Bare Base Solid Waste Generation...with municipal solid waste (MSW) generation rates reported in contemporary literature. Liquid waste stream estimates were made using generally...Therefore, information regarding municipal solid waste (MSW) generation in the United States was also used to derive estimates of the amount and nature ofthe

  17. Geological map of Bare Mountain, Nye County, Nevada

    SciTech Connect

    Monsen, S.A.; Carr, M.D.; Reheis, M.C.; Orkild, P.P.

    1992-12-31

    Bare Mountain comprises the isolated complex of mountain peaks southeast of the town of Beatty in southern Nye County, Nevada. This small mountain range lies between the alluvial basins of Crater Flat to the east and the northern Amargosa Desert to the southwest. The northern boundary of the range is less well defined, but for this report, the terrane of faulted Miocene volcanic rocks underlying Beatty Mountain and the unnamed hills to the east are considered to be the northernmost part of Bare Mountain. The southern tip of the mountain range is at Black Marble, the isolated hill at the southeast corner of the map. The main body of the range, between Fluorspar Canyon and Black Marble, is a folded and complexly faulted, but generally northward-dipping (or southward-dipping and northward-overturned), sequence of weakly to moderately metamorphosed upper Proterozoic and Paleozoic marine strata, mostly miogeoclinal (continental shelf) rocks. The geology of Bare Mountain is mapped at a scale of 1:24,000.

  18. Assembly and integration of thin bare die using laser direct-write

    NASA Astrophysics Data System (ADS)

    Piqué, Alberto; Charipar, Nicholas A.; Auyeung, Ray C. Y.; Kim, Heungsoo; Mathews, Scott A.

    2007-02-01

    Laser-based direct-write (LDW) processes offer unique advantages for the transfer of unpackaged semiconductor bare die for microelectronics assembly applications. Using LDW it is possible to release individual devices from a carrier substrate and transfer them inside a pocket or recess in a receiving substrate using a single UV laser pulse, thus per-forming the same function as pick-and-place machines currently employed in microelectronics assembly. However, conventional pick-and-place systems have difficulty handling small (< 1mm2) and thin (< 100 μm) components. At the Naval Research Laboratory, we have demonstrated the laser release and transfer of intact 1 mm2 wafers with thicknesses down to 10 microns and with high placement accuracy using LDW techniques. Furthermore, given the gentle nature of the laser forward transfer process it is possible to transfer semiconductor bare die of sizes ranging from 0.5 to 10 mm2 without causing any damage to their circuits. Once the devices have been transferred, the same LDW system can then be used to print the metal patterns required to interconnect each device. The implementation of this technique is ideally suited for the assembly of microelectronic components and systems while allowing the overall circuit design and layout to be easily modified or adapted to any specific application or form factor including 3-D architectures. This paper describes how the LDW process can be used as an effective laser die transfer tool and will present analysis of the laser-driven release process as applied to various types of silicon bare dies.

  19. In vitro Growth Pattern of Primary Human Osteoblasts on Calcium Phosphate- and Polymethylmethacrylate-Based Bone Cement.

    PubMed

    Schauwecker, Johannes; Bock, Mark; Pohlig, Florian; Mühlhofer, Heinz; Tübel, Jutta; von Eisenhart-Rothe, Rüdiger; Kirchhoff, Chlodwig

    2017-05-12

    Polymethylmethacrylate (PMMA) and calcium phosphate (Ca-P) cements are widely used for arthroplasty surgery and augmentation of bone defects. However, aseptic implant loosening in absence of wear-induced osteolysis indicates an unfavourable interaction between the cement surface and human osteoblasts. Our underlying hypothesis is that cement surfaces directly modify cell viability, proliferation rate, and cell differentiation. To test this hypothesis, we examined primary human osteoblasts harvested from six individuals. These cells were pooled and subsequently seeded directly on cement pellets prepared from Palacos® R, Palacos® R+G, and Norian® Drillable cements. After incubation for 24 and 72 h, cell viability, proliferation rate, apoptosis rate, and cell differentiation were analysed. Upon cultivation of human osteoblasts on cement surfaces, we observed a significantly reduced cell viability and DNA content compared to the control. Analysis of the apoptosis rate revealed an increase for cells on Palacos R and Norian Drillable, but a significant decrease on Palacos R+G compared to the control. Regarding osteogenic differentiation, significantly lower values of alkaline phosphatase enzyme activity were identified for all cement surfaces after 24 and 72 h compared to cultivation on tissue culture plastic, serving as control. In summary, these data suggest a limited biocompatibility of both PMMA and Ca-P cements, necessitating further research to reduce unfavourable cell-cement interactions and consequently extend implant survival. © 2017 S. Karger AG, Basel.

  20. Patterns of Hand Grip Strength and Detection of Strength Loss in Patients Undergoing Bone Marrow Transplantation: A Feasibility Study.

    PubMed

    Sayre, Cindy A; Belza, Basia; Shannon Dorcy, Kathleen; Phelan, Elizabeth; Whitney, JoAnne D

    2017-09-01

    To determine the feasibility of measuring hand grip strength (HGS) daily in a population of recipients of bone marrow transplantation (BMT), to describe changes in strength measured by HGS, and to describe relationships between laboratory values (hematocrit, hemoglobin, and absolute neutrophil count) and HGS.
. Prospective, longitudinal, repeated measures, within subject.
. Inpatient units at the University of Washington Medical Center in Seattle.
. 33 patients admitted in preparation for BMT or for complications from BMT.
. HGS measured on admission and daily.
. HGS, absolute neutrophil count, hemoglobin, and hematocrit.
. Participants found HGS testing to be relatively easy. Average time to complete testing was 7.2 minutes (SD = 1.95). Nineteen experienced 20% or greater decline in HGS during hospitalization, with nine experiencing decline during the conditioning phase. Age, gender, and hemoglobin correlated with HGS. Strength loss was more likely in those undergoing allogeneic compared to autologous BMT.
. A majority of patients experienced strength decline during BMT, with a subgroup declining during conditioning. A positive relationship existed between HGS and hemoglobin and hematocrit in participants admitted for conditioning for BMT.
. Weakness increases risk for falls. Patients may experience as much as 50% strength loss during the course of hospitalization for BMT. Strength loss occurs in the conditioning phase for some patients.

  1. Different temporal patterns in the expressions of bone morphogenetic proteins and noggin during astroglial scar formation after ischemic stroke.

    PubMed

    Shin, Jin A; Kang, Jihee Lee; Lee, Kyung-Eun; Park, Eun-Mi

    2012-05-01

    Bone morphogenetic proteins (BMPs) and their antagonists have roles in scar formation and regeneration after central nervous system injuries. However, temporal changes in their expression during astroglial scar formation in the ischemic brain are unknown. Here, we examined protein levels of BMP2, BMP7, and their antagonist noggin in the ischemic brain up to 4 weeks after experimental stroke in mice. BMP2 and BMP7 levels were increased from 1 to 4 weeks in the ischemic brain, and their expression was associated with astrogliosis. BMP7 expression was more intense and co-localized in reactive astrocytes in the ischemic subcortex at 1 week. Noggin expression began to increase after 2 weeks and was further increased at 4 weeks only in the ischemic subcortex, but the intensity was weak compared to the intensity of BMPs. Noggin was co-localized mainly in activated microglia. These findings show that expression of BMPs and noggin differed over time, in intensity and in types of cell, and suggest that BMPs and noggin have different roles in the processes of glial scar formation and neurorestoration in the ischemic brain.

  2. Increase of T and B cells and altered BACH2 expression patterns in bone marrow trephines of imatinib-treated patients with chronic myelogenous leukaemia

    PubMed Central

    Von Laffert, Maximilian; Hänel, Mathias; Dietel, Manfred; Anagnostopoulos, Ioannis; Jöhrens, Korinna

    2016-01-01

    The effect of imatinib on T and B cells in patients with chronic myelogenous leukaemia (CML) is not well understood. An upregulation of the transcription factor Broad-complex-Tramtrack-Bric-a-Brac and Cap‘n’collar 1 bZip transcription factor 2 (BACH2), which is involved in the development and differentiation of B cells, was demonstrated in a CML cell line treated with imatinib. The present study retrospectively analysed the expression and distribution of cluster of differentiation (CD)3, CD20 and BACH2 (per 1,000 cells), as well as the co-expression of CD20 and BACH2, using immunohistochemistry in serial bone marrow trephines obtained from 14 CML patients treated with imatinib in comparison to 17 patients with newly diagnosed CML and 6 control trephines. Bone marrow trephines of CML patients in remission under imatinib therapy exhibited significantly higher numbers of CD3 and CD20 infiltrates (partly ordered in aggregates) compared with patients with newly diagnosed CML and control individuals. Similarly, nuclear expression of BACH2 in granulopoietic cells was increased in CML patients treated with imatinib, which may represent the histological correlate of the positive treatment effect. Furthermore, since BACH2 is involved in B cell development, its altered expression patterns by imatinib may be one explanation for high B cell numbers, as revealed by CD20/BACH2 (nuclear)-positive cells. As the present data are preliminary, future prospective studies are required to assess the prognostic and predictive role of BACH2 in patients with CML under targeted therapy. PMID:27698808

  3. Supersonic Bare Metal Cluster Beams. Technical Progress Report, March 16, 1984 - April 1, 1985

    DOE R&D Accomplishments Database

    Smalley, R. E.

    1985-01-01

    There have been four major areas of concentration for the study of bare metal cluster beams: neutral cluster, chemical reactivity, cold cluster ion source development (both positive and negative), bare cluster ion ICR (ion cyclotron resonance) development, and photofragmentation studies of bare metal cluster ions.

  4. 10 CFR 429.35 - Bare or covered (no reflector) medium base compact fluorescent lamps.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Bare or covered (no reflector) medium base compact....35 Bare or covered (no reflector) medium base compact fluorescent lamps. (a) Sampling plan for... reflector) medium base compact fluorescent lamps; and (2) For each basic model of bare or covered (no...

  5. 30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Plans for insulation of existing bare power... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior to...

  6. 30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Plans for insulation of existing bare power... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior to...

  7. 30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Plans for insulation of existing bare power... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior to...

  8. 30 CFR 57.12066 - Guarding trolley wires and bare powerlines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Guarding trolley wires and bare powerlines. 57... MINES Electricity Surface Only § 57.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be guarded...

  9. 30 CFR 77.515 - Bare signal or control wires; voltage.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare signal or control wires; voltage. 77.515... COAL MINES Electrical Equipment-General § 77.515 Bare signal or control wires; voltage. The voltage on bare signal or control wires accessible to personal contact shall not exceed 40 volts. ...

  10. 30 CFR 56.12066 - Guarding trolley wires and bare powerlines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Guarding trolley wires and bare powerlines. 56... Electricity § 56.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be guarded or deenergized. ...

  11. 30 CFR 57.12066 - Guarding trolley wires and bare powerlines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Guarding trolley wires and bare powerlines. 57... MINES Electricity Surface Only § 57.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be...

  12. 30 CFR 57.12066 - Guarding trolley wires and bare powerlines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Guarding trolley wires and bare powerlines. 57... MINES Electricity Surface Only § 57.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be...

  13. 30 CFR 56.12066 - Guarding trolley wires and bare powerlines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Guarding trolley wires and bare powerlines. 56... Electricity § 56.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be guarded or deenergized....

  14. 30 CFR 57.12066 - Guarding trolley wires and bare powerlines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Guarding trolley wires and bare powerlines. 57... MINES Electricity Surface Only § 57.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be...

  15. 30 CFR 56.12066 - Guarding trolley wires and bare powerlines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Guarding trolley wires and bare powerlines. 56... Electricity § 56.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be guarded or deenergized....

  16. 30 CFR 56.12066 - Guarding trolley wires and bare powerlines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Guarding trolley wires and bare powerlines. 56... Electricity § 56.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be guarded or deenergized....

  17. 30 CFR 56.12066 - Guarding trolley wires and bare powerlines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Guarding trolley wires and bare powerlines. 56... Electricity § 56.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be guarded or deenergized....

  18. 30 CFR 77.515 - Bare signal or control wires; voltage.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Bare signal or control wires; voltage. 77.515... COAL MINES Electrical Equipment-General § 77.515 Bare signal or control wires; voltage. The voltage on bare signal or control wires accessible to personal contact shall not exceed 40 volts....

  19. 10 CFR 429.35 - Bare or covered (no reflector) medium base compact fluorescent lamps.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Bare or covered (no reflector) medium base compact....35 Bare or covered (no reflector) medium base compact fluorescent lamps. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to bare or covered...

  20. 10 CFR 429.35 - Bare or covered (no reflector) medium base compact fluorescent lamps.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Bare or covered (no reflector) medium base compact....35 Bare or covered (no reflector) medium base compact fluorescent lamps. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to bare or covered...

  1. 30 CFR 57.12066 - Guarding trolley wires and bare powerlines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Guarding trolley wires and bare powerlines. 57... MINES Electricity Surface Only § 57.12066 Guarding trolley wires and bare powerlines. Where metallic tools or equipment can come in contact with trolley wires or bare powerlines, the lines shall be...

  2. 30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Plans for insulation of existing bare power... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior...

  3. 30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Plans for insulation of existing bare power... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior...

  4. Practice patterns and predictors of followup imaging after a negative bone scan in men with castration resistant prostate cancer: results from the SEARCH database.

    PubMed

    Sourbeer, Katharine N; Howard, Lauren E; Moreira, Daniel M; Amarasekara, Hiruni S; Chow, Lydia D; Cockrell, Dillon C; Hanyok, Brian T; Pratson, Connor L; Kane, Christopher J; Terris, Martha K; Aronson, William J; Cooperberg, Matthew R; Amling, Christopher L; Hernandez, Rohini K; Freedland, Stephen J

    2015-04-01

    We investigated imaging practice patterns in men with nonmetastatic (M0) castration resistant prostate cancer. We analyzed data on 247 patients with documented M0 CRPC from the SEARCH database. Patients were selected regardless of primary treatment modality and all had a negative bone scan after a castration resistant prostate cancer diagnosis. Cox models were used to test associations of time to a second imaging test with several demographic and clinical factors. During a median followup of 29.0 months (IQR 12.9-43.5) after a post-castration resistant prostate cancer bone scan was negative, 190 patients (77%) underwent a second imaging test. On univariable analysis patients with higher prostate specific antigen (HR 1.13, p = 0.016), shorter prostate specific antigen doubling time (HR 0.79, p < 0.001) and faster prostate specific antigen velocity (HR 1.01, p < 0.001) were more likely to undergo a second imaging test. Treatment center was also a significant predictor of a second imaging test (p = 0.010). No other factor was a significant predictor. Results were similar on multivariable analysis. It was estimated that approximately 20% of men with a prostate specific antigen doubling time of less than 3 months did not undergo an imaging test in the first year after a post-castration resistant prostate cancer negative bone scan. However, 50% of patients with prostate specific antigen doubling time 15 months or greater underwent a second imaging test in the first year. Clinicians use some known predictors of positive imaging tests to determine which patients with M0 castration resistant prostate cancer undergo a second imaging test . However, there may be under imaging in those at high risk and over imaging in those at low risk. Further studies are needed to identify risk factors for metastasis and form clear imaging guidelines in patients with M0 castration resistant prostate cancer. Copyright © 2015 American Urological Association Education and Research, Inc

  5. Evaporation Dynamics of Moss and Bare Soil in Boreal Forests

    NASA Astrophysics Data System (ADS)

    Dempster, S.; Young, J. M.; Barron, C. G.; Bolton, W. R.

    2013-12-01

    Evaporation dynamics of mosses is a critical process in boreal and arctic systems and represents a key uncertainty in hydrology and climate models. At this point, moss evaporation is not well quantified at the plot or landscape scale. Relative to bare soil or litter evaporation, moss evaporation can be challenging to predict because the water flux is not isolated to the moss surface. Evaporation can originate from nearly 10 cm below the surface. Some mosses can wick moisture from even deeper than 10 cm, which subsequently evaporates. The goal of this study was to use field measurements to quantify the moss evaporation dynamics in a coniferous forest relative to bare ground or litter evaporation dynamics in a deciduous forest in Interior Alaska. Measurements were made in two ecosystem types within the boreal forest of Interior Alaska: a deciduous forest devoid of moss and a coniferous forest with a thick moss layer. A small clear chamber was attached to a LiCor 840 infrared gas analyzer in a closed loop system with a low flow rate. Water fluxes were measured for ~ 90 seconds on each plot in dry and wet soil and moss conditions. Additional measurements included: soil temperature, soil moisture, air temperature, barometric pressure, dew point, relative humidity, and wind speed. Thermal infrared images were also captured in congruence with water flux measurements to determine skin temperature. We found that the moss evaporation rate was over 100% greater than the soil evaporation rate (0.057 g/min vs. 0.024 g/min), and evaporation rates in both systems were most strongly driven by relative humidity and surface temperature. Surface temperature was lower at the birch site than the black spruce site because trees shade the surface beneath the birch. High fluxes associated with high water content were sustained for a longer period of time over the mosses compared to the bare soil. The thermal IR data showed that skin temperature lagged the evaporation flux, such that the

  6. Bare skin, blood and the evolution of primate colour vision.

    PubMed

    Changizi, Mark A; Zhang, Qiong; Shimojo, Shinsuke

    2006-06-22

    We investigate the hypothesis that colour vision in primates was selected for discriminating the spectral modulations on the skin of conspecifics, presumably for the purpose of discriminating emotional states, socio-sexual signals and threat displays. Here we show that, consistent with this hypothesis, there are two dimensions of skin spectral modulations, and trichromats but not dichromats are sensitive to each. Furthermore, the M and L cone maximum sensitivities for routine trichromats are optimized for discriminating variations in blood oxygen saturation, one of the two blood-related dimensions determining skin reflectance. We also show that, consistent with the hypothesis, trichromat primates tend to be bare faced.

  7. Rethinking biopower: posthumanism, bare life, and emancipatory work.

    PubMed

    Cloyes, Kristin G

    2010-01-01

    This article answers a call, recently published in Advances in Nursing Science, to more fully explore the use of Italian political philosopher Giorgio Agamben's theory of biopower in nursing research and scholarship. Giorgio Agamben argues that biopower is not a modern phenomenon, and critical analysis of the historical origins of Western political practice shows how humanist discourse has been complicit in a long tradition of marginalization and violence, accomplished in each era by designating certain classes of human beings as "bare life." I discuss how I have used Agamben's theory to frame my own research, and the challenges of applying this theory in emancipatory work.

  8. High-performance, bare silver nanowire network transparent heaters.

    PubMed

    Ergun, Orcun; Coskun, Sahin; Yusufoglu, Yusuf; Unalan, Husnu Emrah

    2016-11-04

    Silver nanowire (Ag NW) networks are one of the most promising candidates for the replacement of indium tin oxide (ITO) thin films in many different applications. Recently, Ag-NW-based transparent heaters (THs) showed excellent heating performance. In order to overcome the instability issues of Ag NW networks, researchers have offered different hybrid structures. However, these approaches not only require extra processing, but also decrease the optical performance of Ag NW networks. So, it is important to investigate and determine the thermal performance limits of bare-Ag-NW-network-based THs. Herein, we report on the effect of NW density, contact geometry, applied bias, flexing and incremental bias application on the TH performance of Ag NW networks. Ag-NW-network-based THs with a sheet resistance and percentage transmittance of 4.3 Ω sq(-1) and 83.3%, respectively, and a NW density of 1.6 NW μm(-2) reached a maximum temperature of 275 °C under incremental bias application (5 V maximum). With this performance, our results provide a different perspective on bare-Ag-NW-network-based transparent heaters.

  9. High-performance, bare silver nanowire network transparent heaters

    NASA Astrophysics Data System (ADS)

    Ergun, Orcun; Coskun, Sahin; Yusufoglu, Yusuf; Emrah Unalan, Husnu

    2016-11-01

    Silver nanowire (Ag NW) networks are one of the most promising candidates for the replacement of indium tin oxide (ITO) thin films in many different applications. Recently, Ag-NW-based transparent heaters (THs) showed excellent heating performance. In order to overcome the instability issues of Ag NW networks, researchers have offered different hybrid structures. However, these approaches not only require extra processing, but also decrease the optical performance of Ag NW networks. So, it is important to investigate and determine the thermal performance limits of bare-Ag-NW-network-based THs. Herein, we report on the effect of NW density, contact geometry, applied bias, flexing and incremental bias application on the TH performance of Ag NW networks. Ag-NW-network-based THs with a sheet resistance and percentage transmittance of 4.3 Ω sq-1 and 83.3%, respectively, and a NW density of 1.6 NW μm-2 reached a maximum temperature of 275 °C under incremental bias application (5 V maximum). With this performance, our results provide a different perspective on bare-Ag-NW-network-based transparent heaters.

  10. Laser impingement on bare and encased high explosives: safety limits

    SciTech Connect

    Roeske, F

    1999-03-15

    During the course of experiments involving high explosives, (HE), alignment lasers are often employed where the laser beam impinges upon a metal encased HE sample or on the bare HE itself during manned operations. While most alignment lasers are of low enough power so as not to be of concern, safety questions arise when considering the maximum credible power output of the laser in a failure mode, or when multiple laser spots are focused onto the experiment simultaneously. Safety questions also arise when the focused laser spot size becomes very small, on the order of 100 {micro}m or less. This paper addresses these concerns by describing a methodology for determining safety margins for laser impingement on metal encased HE as well as one for bare HE. A variety of explosives encased in Al, Cu, Ta and stainless steel were tested using the first of these techniques. Additional experiments were performed using the second method where the laser beam was focused directly on eight different samples of pressed-powder HE.

  11. Bare Metal Stenting for Endovascular Exclusion of Aortic Arch Thrombi

    SciTech Connect

    Mahnken, Andreas H.; Hoffman, Andras; Autschbach, Ruediger; Damberg, Anneke L. M.

    2013-08-01

    BackgroundAortic thrombi in the ascending aorta or aortic arch are rare but are associated with a relevant risk of major stroke or distal embolization. Although stent grafting is commonly used as a treatment option in the descending aorta, only a few case reports discuss stenting of the aortic arch for the treatment of a thrombus. The use of bare metal stents in this setting has not yet been described.MethodsWe report two cases of ascending and aortic arch thrombus that were treated by covering the thrombus with an uncovered stent. Both procedures were performed under local anesthesia via a femoral approach. A femoral cutdown was used in one case, and a total percutaneous insertion was possible in the second case.ResultsBoth procedures were successfully performed without any periprocedural complications. Postoperative recovery was uneventful. In both cases, no late complications or recurrent embolization occurred at midterm follow-up, and control CT angiography at 1 respectively 10 months revealed no stent migration, freely perfused supra-aortic branches, and no thrombus recurrence.ConclusionTreating symptomatic thrombi in the ascending aorta or aortic arch with a bare metal stent is feasible. This technique could constitute a minimally invasive alternative to a surgical intervention or complex endovascular therapy with fenestrated or branched stent grafts.

  12. The Integrity bare-metal stent made by continuous sinusoid technology.

    PubMed

    Turco, Mark A

    2011-05-01

    The Integrity Coronary Stent System (Medtronic Vascular, CA, USA) is a low-profile, open-cell, cobalt-chromium-alloy advanced bare-metal iteration of the well-known Driver/Micro-Driver Coronary Stent System (Medtronic Vascular). The Integrity stent is made with a process called continuous sinusoid technology. This process allows stent construction via wrapping a single thin strand of wire around a mandrel in a sinusoid configuration, with laser fusion of adjacent crowns. The wire-forming process and fusion pattern provide the stent with a continuous preferential bending plane, intended to allow easier access to, and smoother tracking within, distal and tortuous vessels while radial strength is maintained. Continuous sinusoid technology represents innovation in the design of stent platforms and will provide a future stent platform for newer technology, including drug-eluting stent platforms, drug-filled stents and core wire stents.

  13. A Bare Bones Reference Collection for Small and Medium-Sized Public Libraries in Maine.

    ERIC Educational Resources Information Center

    Southern Maine Library District, Portland.

    This reference list was compiled to offer Maine librarians who serve communities with the resources of small- or medium-sized libraries a starting point to assess their reference collections for breadth and depth. Initially based on a list distributed by the Vermont Department of Libraries in 1987, this guide evaluates reference materials on the…

  14. These Small Schools Pooled Resources to Beef Up Bare-Bones Curriculums.

    ERIC Educational Resources Information Center

    Ditzler, Lolita

    1984-01-01

    In the Midwest, three types of cooperation among rural school districts have supplemented rural schools' limited curricula and facilities: (1) shared classes, with cooperative transportation between schools; (2) shared classes via cable television; and (3) shared extracurricular activities. (JW)

  15. These Small Schools Pooled Resources to Beef Up Bare-Bones Curriculums.

    ERIC Educational Resources Information Center

    Ditzler, Lolita

    1984-01-01

    In the Midwest, three types of cooperation among rural school districts have supplemented rural schools' limited curricula and facilities: (1) shared classes, with cooperative transportation between schools; (2) shared classes via cable television; and (3) shared extracurricular activities. (JW)

  16. Associations between the 2007 Medicare reimbursement reduction for bone mineral density testing and osteoporosis drug therapy patterns of female Medicare beneficiaries

    PubMed Central

    Kim, Sun Jung; Lee, Joo Hun; Kim, Sulgi; Nakagawa, Shunichi; Bertelson, Heather; Lam, Julia; Yoo, Ji Won

    2014-01-01

    Objective To examine how drug therapy patterns for osteoporosis have changed after the Medicare Physician Fee Schedule (MPFS) reimbursement reduction in 2007, in relation to follow-up bone mineral density (BMD) testing status. Methods We used a retrospective temporal shift design to examine changes in drug therapy patterns before (Phase 1: January 1, 2005–December 31, 2006) and after (Phase 2: July 1, 2007–June 30, 2009) the MPFS reimbursement reduction in 2007, Cleveland, OH, USA. Participants were osteoporotic older women in Phase 1 (n=1,340) and Phase 2 (n=1,437). The main outcomes were a) adherence, b) adjustment, c) occurrence of an extended gap, and d) restarting drug therapy after an extended gap. Follow-up BMD testing status by study phase and location were also analyzed. Results BMD testing rates at physicians’ offices decreased from 64.5% in Phase 1 to 58.4% in Phase 2 (P=0.02); however, testing rates in hospital outpatient settings increased (from 20.8% to 24.5%). There were also decreases in drug therapy adjustment from 15.9% in Phase 1 to 11.6% in Phase 2 (odds ratio [OR]: 0.73; P<0.01) and in restarting drug therapy after an extended gap (55.4% in Phase 1 and 43.6% in Phase 2; OR: 0.76; P<0.01). Conclusion There were no changes in the overall rate of follow-up BMD testing. The rates of drug adjustments and restarting drug therapy after an extended gap did decrease. These decreases were more evident when follow-up BMD testing was not performed. PMID:25028539

  17. Associations between the 2007 Medicare reimbursement reduction for bone mineral density testing and osteoporosis drug therapy patterns of female Medicare beneficiaries.

    PubMed

    Kim, Sun Jung; Lee, Joo Hun; Kim, Sulgi; Nakagawa, Shunichi; Bertelson, Heather; Lam, Julia; Yoo, Ji Won

    2014-01-01

    To examine how drug therapy patterns for osteoporosis have changed after the Medicare Physician Fee Schedule (MPFS) reimbursement reduction in 2007, in relation to follow-up bone mineral density (BMD) testing status. We used a retrospective temporal shift design to examine changes in drug therapy patterns before (Phase 1: January 1, 2005-December 31, 2006) and after (Phase 2: July 1, 2007-June 30, 2009) the MPFS reimbursement reduction in 2007, Cleveland, OH, USA. Participants were osteoporotic older women in Phase 1 (n=1,340) and Phase 2 (n=1,437). The main outcomes were a) adherence, b) adjustment, c) occurrence of an extended gap, and d) restarting drug therapy after an extended gap. Follow-up BMD testing status by study phase and location were also analyzed. BMD testing rates at physicians' offices decreased from 64.5% in Phase 1 to 58.4% in Phase 2 (P=0.02); however, testing rates in hospital outpatient settings increased (from 20.8% to 24.5%). There were also decreases in drug therapy adjustment from 15.9% in Phase 1 to 11.6% in Phase 2 (odds ratio [OR]: 0.73; P<0.01) and in restarting drug therapy after an extended gap (55.4% in Phase 1 and 43.6% in Phase 2; OR: 0.76; P<0.01). There were no changes in the overall rate of follow-up BMD testing. The rates of drug adjustments and restarting drug therapy after an extended gap did decrease. These decreases were more evident when follow-up BMD testing was not performed.

  18. Cancellous structure of tarsal bones.

    PubMed Central

    Sinha, D N

    1985-01-01

    The internal structure of the tarsal bones has been studied to investigate their cancellous architecture. It is revealed that these bones have fine and coarse meshworks and even a tendency for obliteration of the trabecular pattern in the bones lying distal to this midtarsal joint. Internal structure of the talus does not show an arched pattern of bony lamellae. An increased density of bony lamellae in the internal structure of the navicular bone could result from excessive stress, enforced by its close relationship to the three cuneiform bones. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 PMID:4066465

  19. The Facial Growth Pattern and the Amount of Palatal Bone Deficiency Relative to Cleft Size Should Be Considered in Treatment Planning

    PubMed Central

    2016-01-01

    Background: The aim of this study is to determine the best surgical/orthodontic treatment plan for the complete bilateral and unilateral cleft lip and palate patient to achieve all treatment goals of facial aesthetics, speech, dental function, and psychosocial development. Methods: Review of 40 years of serial complete bilateral cleft lip and palate and complete unilateral cleft lip and palate dental casts and photographs from birth to adolescence, with serial cephs starting at 4 years. This was part of a multicenter international 3-dimensional palatal growth study of serial dental casts of patients who developed good speech, occlusion, and facial growth. Results: Nasoalveolar molding and gingivoperiosteoplasty were introduced without proven longitudinal benefits. The procedure bodily retruded the premaxilla, which “telescoped” backward causing synostosis at the premaxillary vomerine suture. The resulting midfacial recessiveness with an anterior dental crossbite can only be corrected by midfacial protraction or a Le Fort I surgery. Conclusions: Staged orthodontic/surgical treatment limiting premaxillary retraction forces to lip adhesion or forces that cause only premaxillary ventroflexion produce the best results. The palatal cleft should be closed between 18 and 24 months when the ratio of the cleft to the palatal size medial to the alveolar ridge is at least 10%. The protruding premaxilla should only be ventroflexed but never bodily retruded. The facial growth pattern and degree of palatal bone deficiency are the main items to be considered in treatment planning. PMID:27579230

  20. Bone development

    PubMed Central

    Berendsen, Agnes D.; Olsen, Bjorn R.

    2015-01-01

    The development of the vertebrate skeleton reflects its evolutionary history. Cartilage formation came before biomineralization and a head skeleton evolved before the formation of axial and appendicular skeletal structures. This review describes the processes that result in endochondral and intramembranous ossification, the important roles of growth and transcription factors, and the consequences of mutations in some of the genes involved. Following a summary of the origin of cartilage, muscle, and tendon cell lineages in the axial skeleton, we discuss the role of muscle forces in the formation of skeletal architecture and assembly of musculoskeletal functional units. Finally, ontogenetic patterning of bones in response to mechanical loading is reviewed. PMID:26453494

  1. Hypercalciuric Bone Disease

    NASA Astrophysics Data System (ADS)

    Favus, Murray J.

    2008-09-01

    Hypercalciuria plays an important causal role in many patients with calcium oxalate (CaOx) stones. The source of the hypercalciuria includes increased intestinal Ca absorption and decreased renal tubule Ca reabsorption. In CaOx stone formers with idiopathic hypercalciuria (IH), Ca metabolic balance studies have revealed negative Ca balance and persistent hypercalciuria in the fasting state and during low dietary Ca intake. Bone resorption may also contribute to the high urine Ca excretion and increase the risk of bone loss. Indeed, low bone mass by DEXA scanning has been discovered in many IH patients. Thiazide diuretic agents reduce urine Ca excretion and may increase bone mineral density (BMD), thereby reducing fracture risk. Dietary Ca restriction that has been used unsuccessfully in the treatment of CaOx nephrolithiasis in the past may enhance negative Ca balance and accelerate bone loss. DEXA scans may demonstrate low BMD at the spine, hip, or forearm, with no predictable pattern. The unique pattern of bone histologic changes in IH differs from other causes of low DEXA bone density including postmenopausal osteoporosis, male hypogonadal osteoporosis, and glucocorticoid-induced osteoporosis. Hypercalciuria appears to play an important pathologic role in the development of low bone mass, and therefore correction of urine Ca losses should be a primary target for treatment of the bone disease accompanying IH.

  2. Prognostic Value of Bone Marrow Tracer Uptake Pattern in Baseline PET Scans in Hodgkin Lymphoma: Results from an International Collaborative Study.

    PubMed

    Zwarthoed, Colette; El-Galaly, Tarec Cristoffer; Canepari, Maria; Ouvrier, Matthieu John; Viotti, Julien; Ettaiche, Marc; Viviani, Simonetta; Rigacci, Luigi; Trentin, Livio; Rusconi, Chiara; Luminari, Stefano; Cantonetti, Maria; Bolis, Silvia; Borra, Anna; Darcourt, Jacques; Salvi, Flavia; Subocz, Edyta; Tajer, Joanna; Kulikowski, Waldemar; Malkowski, Bogdan; Zaucha, Jan Maciej; Gallamini, Andrea

    2017-08-01

    PET/CT-ascertained bone marrow involvement (BMI) constitutes the single most important reason for upstaging by PET/CT in Hodgkin lymphoma (HL). However, BMI assessment in PET/CT can be challenging. This study analyzed the clinicopathologic correlations and prognostic meaning of different patterns of bone marrow (BM) (18)F-FDG uptake in HL. Methods: One hundred eighty newly diagnosed early unfavorable and advanced-stage HL patients, all scanned at baseline and after 2 adriamycin-bleomycin-vinblastine-dacarbazine (ABVD) courses with (18)F-FDG PET, enrolled in 2 international studies aimed at assessing the role of interim PET scanning in HL, were retrospectively included. Patients were treated with ABVD × 4-6 cycles and involved-field radiation when needed, and no treatment adaptation on interim PET scanning was allowed. Two masked reviewers independently reported the scans. Results: Thirty-eight patients (21.1%) had focal lesions (fPET(+)), 10 of them with a single (unifocal) and 28 with multiple (multifocal) BM lesions. Fifty-three patients (29.4%) had pure strong (>liver) diffuse uptake (dPET(+)) and 89 (48.4%) showed no or faint (≤liver) BM uptake (nPET(+)). BM biopsy was positive in 6 of 38 patients (15.7%) for fPET(+), in 1 of 53 (1.9%) for dPET(+), and in 5 of 89 (5.6%) for nPET(+) dPET(+) was correlated with younger age, higher frequency of bulky disease, lower hemoglobin levels, higher leukocyte counts, and similar diffuse uptake in the spleen. Patients with pure dPET(+) had a 3-y progression-free survival identical to patients without any (18)F-FDG uptake (82.9% and 82.2%, respectively, P = 0.918). However, patients with fPET+ (either unifocal or multifocal) had a 3-y progression-free survival significantly inferior to patients with dPET+ and nPET+ (66.7% and 82.5%, respectively, P = 0.03). The κ values for interobserver agreement were 0.84 for focal uptake and 0.78 for diffuse uptake. Conclusion: We confirmed that (18)F-FDG PET scanning is a reliable

  3. Shock initiation of bare and covered explosives by projectile impact

    SciTech Connect

    Bahl, K L; Vantine, H C; Weingart, R C

    1981-04-22

    Shock initiation thresholds of bare and covered PBX-9404 and an HMX/TATB explosive called RX-26-AF were measured. The shocks were produced by the impact of flat-nosed and round-nosed steel projectiles in the velocity range of 0.5 to 2.2 km/s. Three types of coverings were used, 2 or 6 mm of tantalum, and a composite of aluminum and plastic. An Eulerian code containing material-strength and explosive-initiation models was used to evaluate our ability to calculate the shock initiation thresholds. These code calculations agreed well with the flat-nosed experimental data, but not so well with the round-nosed data.

  4. The bare lymphocyte syndrome and the regulation of MHC expression.

    PubMed

    Reith, W; Mach, B

    2001-01-01

    The bare lymphocyte syndrome (BLS) is a hereditary immunodeficiency resulting from the absence of major histocompatibility complex class II (MHCII) expression. Considering the central role of MHCII molecules in the development and activation of CD4(+) T cells, it is not surprising that the immune system of the patients is severely impaired. BLS is the prototype of a "disease of gene regulation." The affected genes encode RFXANK, RFX5, RFXAP, and CIITA, four regulatory factors that are highly specific and essential for MHCII genes. The first three are subunits of RFX, a trimeric complex that binds to all MHCII promoters. CIITA is a non-DNA-binding coactivator that functions as the master control factor for MHCII expression. The study of RFX and CIITA has made major contributions to our comprehension of the molecular mechanisms controlling MHCII genes and has made this system into a textbook model for the regulation of gene expression.

  5. Achievement of a superpolish on bare stainless steel

    NASA Astrophysics Data System (ADS)

    Howells, Malcolm R.; Casstevens, John M.

    1997-11-01

    We report the achievement of a superpolished surface, suitable for x-ray reflection, on bare stainless steel. The rms roughness obtained on various samples varied from 2.2 to 4.2 angstroms, as measured by an optical profiler with a bandwidth 0.29 - 100 mm-1. The type 17-4 PH precipitation-hardening stainless steel used to make the mirrors is also capable of ultrastability and has good manufacturability. This combination of properties makes it an excellent candidate material for mirror substrates. We describe the successful utilization of this type of steel in making elliptical-cylinder mirrors for a soft-x-ray microprobe system at the Advanced Light Source, and discuss possible reasons for its unusual stability and polishability.

  6. Turbulence-induced thermal signatures over evaporating bare soil surfaces

    NASA Astrophysics Data System (ADS)

    Haghighi, Erfan; Or, Dani

    2015-07-01

    Soil wetness and airflow turbulence are key factors affecting surface energy balance components thereby influencing surface skin temperature. Turbulent eddies interacting with evaporating surfaces often induce localized and intermittent evaporative and sensible heat fluxes that leave distinct thermal signatures. These surface thermal fluctuations observable by infrared thermography (IRT) offer a means for characterization of overlaying turbulent airflows and remote quantification of surface wetness. We developed a theoretical and experimental methodology for using rapid IR surface temperature measurements to deduce surface wetness and evaporative fluxes from smooth bare soils. The mechanistic model provides theoretical links between surface thermal fluctuations, soil, and aerodynamic properties enabling thermal inferences of soil wetness with explicit consideration of soil thermal capacity and airflow turbulence effects. The method potentially improves accuracy of soil wetness assessment by IRT-based techniques whose performance is strongly influenced by surface-turbulence interactions and offers new ways for quantifying fluxes directly at their origin.

  7. Achievement of a superpolish on bare stainless steel

    SciTech Connect

    Howells, M.R.; Casstevens, J.

    1997-08-01

    We report the achievement of a superpolished surface, suitable for x-ray reflection, on bare stainless steel. The rms roughness obtained on various samples varied from 2.2 to 4.2 {angstrom}, as measured by an optical profiler with a bandwidth 0.29-100 mm{sup -1}. The type 17-4 PH precipitation-hardening stainless steel used to make the mirrors is also capable of ultrastability and has good manufactureability. This combination of properties makes it an excellent candidate material for mirror substrates. We describe the successful utilization of this type of steel in making elliptical-cylinder mirrors for a soft-x-ray microprobe system at the Advanced Light Source, and discuss possible for its unusual stability and polishability.

  8. Near-edge wrack effects on bare sediments: Small scale variation matters in the monitoring of sandy beaches.

    PubMed

    MacMillan, Mitchell R; Tummon Flynn, Paula; Duarte, Cristian; Quijón, Pedro A

    2016-12-01

    The influence of wrack on sandy beach communities is well-documented but its effect on bare sediments located immediately beyond its edge has not yet been tested. This study aimed to explore these effects by surveying bare sediments located at increasing distances (0.5-2 m) from the wrack in five sandy beaches on Prince Edward Island, Atlantic Canada. In addition, we tested the influence of wrack with a field manipulation using wrack patches made up of rockweed bundles. The survey indicated that a modest but significant number of amphipods and beetles occupied bare sediments located 0.5 m from the edge of the wrack, but that those numbers dropped in sediments 1 m away and farther. The outcome of the field manipulation showed a similar pattern. Although small in spatial scale, our results have implications for the monitoring sandy beaches affected by scattered as well as heavy wrack input. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Molecular markers based on LTR retrotransposons BARE-1 and Jeli uncover different strata of evolutionary relationships in diploid wheats.

    PubMed

    Konovalov, Fedor A; Goncharov, Nikolay P; Goryunova, Svetlana; Shaturova, Aleksandra; Proshlyakova, Tatyana; Kudryavtsev, Alexander

    2010-06-01

    Molecular markers based on retrotransposon insertions are widely used for various applications including phylogenetic analysis. Multiple cases were described where retrotransposon-based markers, namely sequence-specific amplification polymorphism (SSAP), were superior to other marker types in resolving the phylogenetic relationships due to their higher variability and informativeness. However, the patterns of evolutionary relationships revealed by SSAP may be dependent on the underlying retrotransposon activity in different periods of time. Hence, the proper choice of retrotransposon family is essential for obtaining significant results. We compared the phylogenetic trees for a diverse set of diploid A-genome wheat species (Triticum boeoticum, T. urartu and T. monococcum) based on two unrelated retrotransposon families, BARE-1 and Jeli. BARE-1 belongs to Copia class and has a uniform distribution between common wheat (T. aestivum) genomes of different origin (A, B and D), indicating similar activity in the respective diploid genome donors. Gypsy-class family Jeli was found by us to be an A-genome retrotransposon with >70% copies residing in A genome of hexaploid common wheat, suggesting a burst of transposition in the history of A-genome progenitors. The results indicate that a higher Jeli transpositional activity was associated with T. urartu versus T. boeoticum speciation, while BARE-1 produced more polymorphic insertions during subsequent intraspecific diversification; as an outcome, each retrotransposon provides more informative markers at the corresponding level of phylogenetic relationships. We conclude that multiple retroelement families should be analyzed for an image of evolutionary relationships to be solid and comprehensive.

  10. Diurnal emissivity dynamics in bare versus biocrusted sand dunes

    NASA Astrophysics Data System (ADS)

    Rozenstein, O.

    2015-12-01

    Land surface emissivity (LSE) in the thermal infrared depends mainly on the ground cover and on changes in soil moisture. The LSE is a critical variable that affects the prediction accuracy of geophysical models requiring land surface temperature as an input, highlighting the need for an accurate derivation of LSE. The primary aim of this study was to test the hypothesis that diurnal changes in emissivity, as detected from space, are larger for areas mostly covered by biocrusts (composed mainly of cyanobacteria) than for bare sand areas. The LSE dynamics were monitored from geostationary orbit by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) over a sand dune field in a coastal desert region extending across both sides of the Israel-Egypt political borderline. Different land-use practices by the two countries have resulted in exposed, active sand dunes on the Egyptian side (Sinai), and dunes stabilized by biocrusts on the Israeli side (Negev). Since biocrusts adsorb more moisture from the atmosphere than bare sand does, and LSE is affected by the soil moisture, diurnal fluctuations in LSE were larger for the crusted dunes in the 8.7 μm channel. This phenomenon is attributed to water vapor adsorption by the sand / biocrust particles. The results indicate that LSE is sensitive to minor changes in soil water content caused by water vapor adsorption and can, therefore, serve as a tool for quantifying this effect, which has a large spatial impact. As biocrusts cover vast regions in deserts worldwide, this discovery has repercussions for LSE estimations in deserts around the globe, and these LSE variations can potentially have considerable effects on geophysical models from local to regional scales.

  11. Diurnal emissivity dynamics in bare versus biocrusted sand dunes.

    PubMed

    Rozenstein, Offer; Agam, Nurit; Serio, Carmine; Masiello, Guido; Venafra, Sara; Achal, Stephen; Puckrin, Eldon; Karnieli, Arnon

    2015-02-15

    Land surface emissivity (LSE) in the thermal infrared depends mainly on the ground cover and on changes in soil moisture. The LSE is a critical variable that affects the prediction accuracy of geophysical models requiring land surface temperature as an input, highlighting the need for an accurate derivation of LSE. The primary aim of this study was to test the hypothesis that diurnal changes in emissivity, as detected from space, are larger for areas mostly covered by biocrusts (composed mainly of cyanobacteria) than for bare sand areas. The LSE dynamics were monitored from geostationary orbit by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) over a sand dune field in a coastal desert region extending across both sides of the Israel-Egypt political borderline. Different land-use practices by the two countries have resulted in exposed, active sand dunes on the Egyptian side (Sinai), and dunes stabilized by biocrusts on the Israeli side (Negev). Since biocrusts adsorb more moisture from the atmosphere than bare sand does, and LSE is affected by the soil moisture, diurnal fluctuations in LSE were larger for the crusted dunes in the 8.7 μm channel. This phenomenon is attributed to water vapor adsorption by the sand/biocrust particles. The results indicate that LSE is sensitive to minor changes in soil water content caused by water vapor adsorption and can, therefore, serve as a tool for quantifying this effect, which has a large spatial impact. As biocrusts cover vast regions in deserts worldwide, this discovery has repercussions for LSE estimations in deserts around the globe, and these LSE variations can potentially have considerable effects on geophysical models from local to regional scales.

  12. Living Bones, Strong Bones

    NASA Image and Video Library

    In this classroom activity, engineering, nutrition, and physical activity collide when students design and build a healthy bone model of a space explorer which is strong enough to withstand increas...

  13. Probing surface plasmons by bare V-shaped tips: modeling by geometrical optics and rigorous diffraction theory

    NASA Astrophysics Data System (ADS)

    Bose, Gaurav; Hyvärinen, Heikki J.; Tervo, Jani; Turunen, Jari

    2017-02-01

    We consider probing inhomogeneous waves in the near fields of metallic nanostructures with the aid of a dielectric V-shaped wedge connected to a waveguide. A geometrical model based on the local plane interface approach is proposed to describe the interaction of the wedge with the inhomogeneous field. The fundamental ideas behind the geometrical model are validated by comparison with the results given by rigorous diffraction analysis, and applied to probing plasmonic interference patterns generated by metallic gratings with very narrow slits. The model explains intuitively why a bare wedge with a large apex angle is capable of subwavelength resolution in the spirit of scanning near-field microscopy.

  14. Nitrogen controls spatial and temporal variability of substrate-induced respiration within seven years of bare fallow

    NASA Astrophysics Data System (ADS)

    Meyer, Nele; Bornemann, Ludger; Welp, Gerhard; Amelung, Wulf

    2015-04-01

    Bare fallow management goes along with lacking supply of new C sources; yet, little is known on the spatio-temporal controls of microbial adaptation processes. Here we hypothesized that microbial activity parameters decline upon bare fallow but that their spatial patterns are increasingly controlled by nutrient status as fallow management proceeds. To test these hypotheses, we investigated spatial and temporal patterns of substrate-induced respiration (SIR) and basal respiration curves in an arable field after 1, 3, and 7 years of bare fallow but with large within-field heterogeneity of physicochemical soil parameters. The analyses comprised the contents of SOC, mineral nitrogen (Nmin), particulate organic matter (POM), texture of the fine earth, and the proportion of rock fragments as well as basal respiration and several SIR fitting parameters (microbial biomass, microbial growth rates, peak respiration rates, cumulative CO2 release) each with and without additions of mineral N and P. We also repeated substrate (i.e. glucose) additions following the first SIR measurement. The results revealed that most respiration parameters like basal respiration, microbial biomass, and growth rates showed no or inconsistent responses to spatial and temporal patterns of basic soil properties like SOC, Nmin or texture. However, bare fallow changed the shape of the SIR curves; it developed two distinct microbial growth peaks at advanced stages of fallow, i.e. a delayed CO2 release. Likewise, the maximum respiration rate during the first growth phase declined during 7 years of fallow by 47% but its spatial distribution was always correlated with Nmin contents (r = 0.43 - 0.79). The nutrient additions suggested that these changes in SIR curves were caused by N deficiency; the first peak increased after N additions while the second growth phase diminished. Intriguingly, a repeated glucose addition had a similar effect on the SIR curves as the glucose+N addition. Thus, N deficiency

  15. Probing surface plasmons by bare V-shaped tips: modeling by geometrical optics and rigorous diffraction theory

    NASA Astrophysics Data System (ADS)

    Bose, Gaurav; Hyvärinen, Heikki J.; Tervo, Jani; Turunen, Jari

    2017-04-01

    We consider probing inhomogeneous waves in the near fields of metallic nanostructures with the aid of a dielectric V-shaped wedge connected to a waveguide. A geometrical model based on the local plane interface approach is proposed to describe the interaction of the wedge with the inhomogeneous field. The fundamental ideas behind the geometrical model are validated by comparison with the results given by rigorous diffraction analysis, and applied to probing plasmonic interference patterns generated by metallic gratings with very narrow slits. The model explains intuitively why a bare wedge with a large apex angle is capable of subwavelength resolution in the spirit of scanning near-field microscopy.

  16. Bone Cancer

    MedlinePlus

    Cancer that starts in a bone is uncommon. Cancer that has spread to the bone from another ... more common. There are three types of bone cancer: Osteosarcoma - occurs most often between ages 10 and ...

  17. Expression pattern of receptor activator of NFκB (RANK) in a series of primary solid tumors and related bone metastases.

    PubMed

    Santini, Daniele; Perrone, Giuseppe; Roato, Ilaria; Godio, Laura; Pantano, Francesco; Grasso, Donatella; Russo, Antonio; Vincenzi, Bruno; Fratto, Maria Elisabetta; Sabbatini, Roberto; Della Pepa, Chiara; Porta, Camillo; Del Conte, Alessandro; Schiavon, Gaia; Berruti, Alfredo; Tomasino, Rosa Maria; Papotti, Mauro; Papapietro, Nicola; Onetti Muda, Andrea; Denaro, Vincenzo; Tonini, Giuseppe

    2011-03-01

    Receptor activator of NFκB ligand (RANKL), RANK, and osteoprotegerin (OPG) represent the key regulators of bone metabolism both in normal and pathological conditions, including bone metastases. To our knowledge, no previous studies investigated and compared RANK expression in primary tumors and in bone metastases from the same patient. We retrospectively examined RANK expression by immunohistochemistry in 74 bone metastases tissues from solid tumors, mostly breast, colorectal, renal, lung, and prostate cancer. For 40 cases, tissue from the corresponding primary tumor was also analyzed. Sixty-six (89%) of the 74 bone metastases were RANK-positive and, among these, 40 (59.5%) showed more than 50% of positive tumor cells. The median percentage of RANK-positive cells was 60% in primary tumors and metastases, without any statistically significant difference between the two groups (P=0.194). The same percentage was obtained by considering only cases with availability of samples both from primary and metastasis. Our study shows that RANK is expressed by solid tumors, with high concordance between bone metastasis and corresponding primary tumor. These data highlight the central role of RANK/RANKL/OPG pathway as potential therapeutic target not only in bone metastasis management, but also in the adjuvant setting.

  18. EAARL Coastal Topography-Chandeleur Islands, Louisiana, 2010: Bare Earth

    USGS Publications Warehouse

    Nayegandhi, Amar; Bonisteel-Cormier, Jamie M.; Brock, John C.; Sallenger, A.H.; Wright, C. Wayne; Nagle, David B.; Vivekanandan, Saisudha; Yates, Xan; Klipp, Emily S.

    2010-01-01

    These remotely sensed, geographically referenced elevation measurements of lidar-derived bare-earth (BE) and submerged topography datasets were produced collaboratively by the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of a portion of the Chandeleur Islands, acquired March 3, 2010. The datasets are made available for use as a management tool to research scientists and natural-resource managers. An innovative airborne lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multispectral color-infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit, which provide for sub-meter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and the resulting data were then processed using the Airborne Lidar Processing System (ALPS), a custom

  19. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: Bare Earth

    USGS Publications Warehouse

    Smith, Kathryn E.L.; Nayegandhi, Amar; Wright, C. Wayne; Bonisteel, Jamie M.; Brock, John C.

    2009-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived bare earth (BE) topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the National Park Service (NPS), Gulf Coast Network, Lafayette, LA; and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. The purpose of this project is to provide highly detailed and accurate datasets of select barrier islands and peninsular regions of Louisiana, Mississippi, Alabama, and Florida, acquired on June 27-30, 2007. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using

  20. EAARL Topography - Vicksburg National Military Park 2008: Bare Earth

    USGS Publications Warehouse

    Nayegandhi, Amar; Brock, John C.; Wright, C. Wayne; Segura, Martha; Yates, Xan

    2008-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived bare earth (BE) topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the National Park Service (NPS), Gulf Coast Network, Lafayette, LA; and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of the Vicksburg National Military Park in Mississippi, acquired on March 6, 2008. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit, which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and the resulting data were then processed

  1. EAARL Coastal Topography - Northeast Barrier Islands 2007: Bare Earth

    USGS Publications Warehouse

    Nayegandhi, Amar; Brock, John C.; Sallenger, A.H.; Wright, C. Wayne; Yates, Xan; Bonisteel, Jamie M.

    2008-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived bare earth (BE) topography were produced collaboratively by the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of the northeast coastal barrier islands in New York and New Jersey, acquired April 29-30 and May 15-16, 2007. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers and an integrated miniature digital inertial measurement unit, which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and the resulting data were then processed using the Airborne Lidar Processing System (ALPS), a custom

  2. EAARL Coastal Topography-Pearl River Delta 2008: Bare Earth

    USGS Publications Warehouse

    Nayegandhi, Amar; Brock, John C.; Wright, C. Wayne; Miner, Michael D.; Yates, Xan; Bonisteel, Jamie M.

    2009-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived bare earth (BE) topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the University of New Orleans (UNO), Pontchartrain Institute for Environmental Sciences (PIES), New Orleans, LA; and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of a portion of the Pearl River Delta in Louisiana and Mississippi, acquired March 9-11, 2008. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit, which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the

  3. A three-dimensional finite element analysis of a passive and friction fit implant abutment interface and the influence of occlusal table dimension on the stress distribution pattern on the implant and surrounding bone

    PubMed Central

    Sarfaraz, Hasan; Paulose, Anoopa; Shenoy, K. Kamalakanth; Hussain, Akhter

    2015-01-01

    Aims: The aim of the study was to evaluate the stress distribution pattern in the implant and the surrounding bone for a passive and a friction fit implant abutment interface and to analyze the influence of occlusal table dimension on the stress generated. Materials and Methods: CAD models of two different types of implant abutment connections, the passive fit or the slip-fit represented by the Nobel Replace Tri-lobe connection and the friction fit or active fit represented by the Nobel active conical connection were made. The stress distribution pattern was studied at different occlusal dimension. Six models were constructed in PRO-ENGINEER 05 of the two implant abutment connection for three different occlusal dimensions each. The implant and abutment complex was placed in cortical and cancellous bone modeled using a computed tomography scan. This complex was subjected to a force of 100 N in the axial and oblique direction. The amount of stress and the pattern of stress generated were recorded on a color scale using ANSYS 13 software. Results: The results showed that overall maximum Von Misses stress on the bone is significantly less for friction fit than the passive fit in any loading conditions stresses on the implant were significantly higher for the friction fit than the passive fit. The narrow occlusal table models generated the least amount of stress on the implant abutment interface. Conclusion: It can thus be concluded that the conical connection distributes more stress to the implant body and dissipates less stress to the surrounding bone. A narrow occlusal table considerably reduces the occlusal overload. PMID:26929518

  4. Bone and bone turnover.

    PubMed

    Crofton, Patricia M

    2009-01-01

    Children with cancer are exposed to multiple influences that may adversely affect bone health. Some treatments have direct deleterious effects on bone whilst others may have indirect effects mediated through various endocrine abnormalities. Most clinical outcome studies have concentrated on survivors of acute lymphoblastic leukaemia (ALL). There is now good evidence that earlier treatment protocols that included cranial irradiation with doses of 24 Gy or greater may result in growth hormone deficiency and low bone mineral density (BMD) in the lumbar spine and femoral neck. Under current protocols, BMD decreases during intensive chemotherapy and fracture risk increases. Although total body BMD may eventually return to normal after completion of chemotherapy, lumbar spine trabecular BMD may remain low for many years. The implications for long-term fracture risk are unknown. Risk factors for low BMD include high dose methotrexate, higher cumulative doses of glucocorticoids, male gender and low physical activity. BMD outcome in non-ALL childhood cancers has been less well studied but there is evidence that survivors of childhood brain or bone tumours, and survivors of bone marrow transplants for childhood malignancy, all have a high risk of long-term osteopenia. Long-term follow-up is required, with appropriate treatment of any endocrine abnormalities identified.

  5. Electron capture by bare ions on water molecules

    NASA Astrophysics Data System (ADS)

    Rivarola, Roberto; Montenegro, Pablo; Monti, Juan; Fojón, Omar

    2016-05-01

    Single electron capture from water molecules by impact of bare ions is theoretically investigated at intermediate and high collision energies. This reaction is of fundamental importance to determine the deposition of energy in biological matter irradiated with ion beams (hadrontherapy), dominating other ionizing processes of the target at low-intermediate impact velocities and giving principal contributions to the energetic region where electronic stopping power maximizes. The dynamics of the interaction between the aggregates is described within the one active-electron continuum distorted wave-eikonal initial state theory. The orbitals of the target in the ground state are represented using the approximate self-consistent complete neglect of differential orbitals (SC-CNDO) model. The contribution of different molecular orbitals on the partial cross sections to selected n-principal quantum number projectile states is discriminated as well as the collaboration of these n-states on total cross sections. The latter ones are dominated by capture to n=1 states at high enough energies decreasing their contribution as n increases.

  6. Space Test of Bare-Wire Anode Tethers

    NASA Technical Reports Server (NTRS)

    Johnson, L.; Fujii, H. A.; Sanmartin, J. R.

    2007-01-01

    An international team, lead by Tokyo Metropolitan University, is developing a mission concept for a suborbital test of orbital-motion-limited (OML) bare-wire anode current collection for application to electrodynamic tether propulsion. The tether is a tape with a 50-mm width, 0.05-mm thickness, and 1-km length. This will be the first space test of the OML theory. In addition, by being an engineering demonstration (of space tethers), the mission will demonstrate electric beam generation for "sounding" determination of the neutral density profile in the ionospheric "E-layer." If selected by the Institute of Space and Astronautical Science/Japanese Aerospace Exploration Agency (JAXA), the mission will launch in early 2009 using an $520 Sounding Rocket. During ascent, and above =100 km in attitude, the 1-km tape tether will be deployed at a rate of 8 m/s. Once deployed, the tape tether will serve as an anode, collecting ionospheric electrons. The electrons will be expelled into space by a hollow cathode device, thereby completing the circuit and allowing current to flow.This paper will describe the objectives of the proposed mission, the technologies to be employed, and the application of the results to future space missions using electrodynamic tethers for propulsion or power generation.

  7. Fortissimo: A Japanese Space Test Of Bare Wire Anode Tethers

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Fujii, H. A.; Sanmartin, J. R.

    2008-01-01

    A Japanese led international team is developing a suborbital test of orbital-motion-limited (OML) bare wire anode current collection for application to electrodynamic tether (EDT) propulsion. The tether is a tape with a width of 25 mm, thickness of 0.05 mm, and is 300 m in length. This will be the first space test of OML theory. The mission will launch in the summer of 2009 using an S520 Sounding Rocket. During ascent, and above approx. 100 km in attitude, the tape tether will be deployed at a rate of approx. 8 m/s. Once deployed, the tape tether will serve as an anode, collecting ionospheric electrons. The electrons will be expelled into space by a hollow cathode device, thereby completing the circuit and allowing current to flow. The total amount of current collected will be used to assess the validity of OML theory. This paper will describe the objectives of the proposed mission, the technologies to be employed, and the application of the results to future space missions using EDTs for propulsion or power generation.

  8. Analysis of thermionic bare tether operation regimes in passive mode

    NASA Astrophysics Data System (ADS)

    Sanmartín, J. R.; Chen, Xin; Sánchez-Arriaga, G.

    2017-01-01

    A thermionic bare tether (TBT) is a long conductor coated with a low work-function material. In drag mode, a tether segment extending from anodic end A to a zero-bias point B, with the standard Orbital-motion-limited current collection, is followed by a complex cathodic segment. In general, as bias becomes more negative in moving from B to cathodic end C, one first finds space-charge-limited (SCL) emission covering up to some intermediate point B*, then full Richardson-Dushman (RD) emission reaching from B* to end C. An approximate analytical study, which combines the current and voltage profile equations with results from asymptotic studies of the Vlasov-Poisson system for emissive probes, is carried out to determine the parameter domain covering two limit regimes, which are effectively controlled by just two dimensionless parameters involving ambient plasma and TBT material properties. In one such limit regime, no point B* is reached and thus no full RD emission develops. In an opposite regime, SCL segment BB* is too short to contribute significantly to the current balance.

  9. Soil microbial activities beneath Stipa tenacissima L. and in surrounding bare soil

    NASA Astrophysics Data System (ADS)

    Novosadová, I.; Ruiz Sinoga, J. D.; Záhora, J.; Fišerová, H.

    2010-05-01

    Open steppes dominated by Stipa tenacissima L. constitute one of the most representative ecosystems of the semi-arid zones of Eastern Mediterranean Basin (Iberian Peninsula, North of Africa). These steppes show a higher degree of variability in composition and structure. Ecosystem functioning is strongly related to the spatial pattern of grass tussocks. Soils beneath S. tenacissima grass show higher fertility and improved microclimatic conditions, favouring the formation of "resource islands" (Maestre et al., 2007). On the other hand in "resource islands" and in surrounding bare soil exists the belowground zone of influence. The competition for water and resources between plants and microorganisms is strong and mediated trough an enormous variety of exudates and resource depletion intended to regulate soil microbial communities in the rhizosphere, control herbivory, encourage beneficial symbioses, and change chemical and physical properties in soil (Pugnaire et Armas, 2008). Secondary compounds and allelopathy restrict other species growth and contribute to patchy plant distribution. Active root segregation affects not only neighbourś growth but also soil microbial activities. The objective of this study was to assess the effect of Stipa tenacissima on the key soil microbial activities under controlled incubation conditions (basal and potential respiration; net nitrogen mineralization). The experimental plots were located in the province Almería in Sierra de los Filabres Mountains near the village Gérgal (southeast Spain) in the small catchment which is situated between 1090 - 1165 m a.s.l. The area with extent of 82 000 m2 is affected by soil degradation. The climate is semiarid Mediterranean. The mean annual rainfall is of about 240 mm mostly concentrated in autumn and spring. The mean annual temperature is 13.9° C. The studied soil has a loam to sandy clay texture and is classified as Lithosol (FAO-ISRIC and ISSS, 1998). The vegetation of these areas is an

  10. Incidence and risk factors for hip or other bone fractures among hemodialysis patients in the Dialysis Outcomes and Practice Patterns Study.

    PubMed

    Jadoul, M; Albert, J M; Akiba, T; Akizawa, T; Arab, L; Bragg-Gresham, J L; Mason, N; Prutz, K-G; Young, E W; Pisoni, R L

    2006-10-01

    The available data on bone fractures in hemodialysis (HD) patients are limited to results of a few studies of subgroups of patients in the United States. This study describes the prevalence of hip fractures and the incidence and risk factors associated with hip and other fractures in representative groups of HD facilities (n=320) and patients (n=12 782) from the 12 countries in the second phase of the Dialysis Outcomes and Practice Patterns Study (2002-2004). Among prevalent patients, 2.6% had a prior hip fracture. The incidence of fractures was 8.9 per 1000 patient years for new hip fractures and 25.6 per 1000 for any new fracture. Older age (relative risk (RR)(HIP)=1.91, RR(ANY)=1.33, P<0.0001), female sex (RR(HIP)=1.41, P=0.02; RR(ANY)=1.59, P<0.0001), prior kidney transplant (RR(HIP)=2.35, P=0.04; RR(ANY)=1.76, P=0.007), and low serum albumin (RR(HIP)=1.85, RR(ANY)=1.45, per 1 g/dl lower, P<0.0001) were predictive of new fractures. Elevated risk of new hip fracture was observed for selective serotonin reuptake inhibitors and combination narcotic medications (RR=1.63, RR=1.74, respectively, P<0.05). Several medications were associated with risk of any new fracture: narcotic pain medications (RR=1.67, P=0.02), benzodiazepines (RR=1.31, P=0.03), adrenal cortical steroids (RR=1.40, P<0.05), and combination narcotic medications (RR=1.72, P=0.001). Parathyroid hormone (PTH) levels >900 pg/ml were associated with an elevated risk of any new fracture (RR=1.72, P<0.05) versus PTH 150-300. The results suggest that greater selectivity in prescribing several classes of psychoactive drugs and more efficient treatment of secondary hyperparathyroidism may help reduce the burden of fractures in HD patients.

  11. 30 CFR 77.515 - Bare signal or control wires; voltage.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Bare signal or control wires; voltage. 77.515... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.515 Bare signal or control wires; voltage. The voltage on...

  12. 30 CFR 77.515 - Bare signal or control wires; voltage.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Bare signal or control wires; voltage. 77.515... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.515 Bare signal or control wires; voltage. The voltage on...

  13. 30 CFR 77.515 - Bare signal or control wires; voltage.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Bare signal or control wires; voltage. 77.515... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.515 Bare signal or control wires; voltage. The voltage on...

  14. Osteocyte and bone structure.

    PubMed

    Klein-Nulend, Jenneke; Nijweide, Peter J; Burger, Elisabeth H

    2003-06-01

    The osteocyte is the most abundant cell type of bone. There are approximately 10 times as many osteocytes as osteoblasts in adult human bone, and the number of osteoclasts is only a fraction of the number of osteoblasts. Our current knowledge of the role of osteocytes in bone metabolism is far behind our insight into the properties and functions of the osteoblasts and osteoclasts. However, the striking structural design of bone predicts an important role for osteocytes in determining bone structure. Over the past several years, the role of osteocytes as the professional mechanosensory cells of bone, and the lacunocanalicular porosity as the structure that mediates mechanosensing have become clear. Strain-derived flow of interstitial fluid through this porosity seems to mechanically activate the osteocytes, as well as ensure transport of cell signaling molecules, nutrients, and waste products. This concept explains local bone gain and loss--as well as remodeling in response to fatigue damage--as processes supervised by mechanosensitive osteocytes. Alignment during remodeling seems to occur as a result of the osteocyte's sensing different canalicular flow patterns around the cutting cone and reversal zone during loading, therefore determining the bone's structure.

  15. [The bare area of the proximal ulna : An anatomical study on optimizing olecranon osteotomy].

    PubMed

    Hackl, M; Lappen, S; Neiss, W F; Scaal, M; Müller, L P; Wegmann, K

    2016-10-01

    Olecranon osteotomy is an established approach for the treatment of distal humerus fractures. It should be performed through the bare area of the proximal ulna to avoid iatrogenic cartilage lesions. The goal of this study was to analyze the anatomy of the proximal ulna with regard to the bare area and, thereby, to optimize the hitting area of the bare area when performing olecranon osteotomy. The bare areas of 30 embalmed forearm specimens were marked with a radiopaque wire and visualized three-dimensionally with a mobile C‑arm. By means of 3D reconstructions of the data sets, the following measurements were obtained: height of the bare area; span of the bare area-hitting area in transverse osteotomy; ideal angle for olecranon osteotomy to maximize the hitting area of the bare area; distance of the posterior olecranon tip to the entry point of the transverse osteotomy and the ideal osteotomy. The height of the bare area was 4.92 ± 0.81 mm. The hitting area of the transverse osteotomy averaged 3.73 ± 0.89 mm. The "ideal" angle for olecranon osteotomy was 30.7° ± 4.19°. The distance of the posterior olecranon tip to the entry point was 14.08 ± 2.75 mm for the transverse osteotomy and 24.21 ± 3.15 mm for the ideal osteotomy. The hitting area of the bare area in the ideal osteotomy was enhanced significantly when compared to the transverse osteotomy (p < 0.0001). This study provides guide values for correct osteotomy of the olecranon. Moreover, a 30° angulation of the osteotomy can significantly increase the hitting area of the bare area.

  16. URB expression in human bone marrow stromal cells and during mouse development.

    PubMed

    Liu, Yi; Monticone, Massimiliano; Tonachini, Laura; Mastrogiacomo, Maddalena; Marigo, Valeria; Cancedda, Ranieri; Castagnola, Patrizio

    2004-09-17

    Seven genes preferentially expressed in undifferentiated human bone marrow stromal cells (BMSC) with respect to BMSC-derived osteoblasts were previously identified by differential display. Here we characterize the expression of one of these genes, URB, belonging to the sushi-repeat-containing protein superfamily. In culture, URB is expressed in both human primary and cloned BMSC, and is drastically downregulated during osteoblastic differentiation of these cells. Here we show that in mouse tissues a single 3.8kb Urb transcript is detected and that the mouse Urb protein is secreted as a 150kDa glycoprotein. During mouse development Urb RNA is barely detectable in 9dpc embryos and increases at later stages. Both in situ hybridization and immunohistochemistry analysis show Urb expression in mouse embryos starting from 14dpc mostly in cartilage. The temporal and spatial expression pattern of Urb suggests its role in mouse skeletogenesis.

  17. Bone marrow aspiration

    MedlinePlus

    Iliac crest tap; Sternal tap; Leukemia - bone marrow aspiration; Aplastic anemia - bone marrow aspiration; Myelodysplastic syndrome - bone marrow aspiration; Thrombocytopenia - bone marrow aspiration; Myelofibrosis - bone marrow aspiration

  18. Are “Treatment” Bare Metal Stents Superior to “Control” Bare Metal Stents? A meta-analytic approach

    PubMed Central

    Kent, David M; Trikalinos, Thomas A

    2011-01-01

    Background It has been suggested that the benefits of drug-eluting stents compared to bare metal stents (BMS) have been over-estimated in part because target lesion/vessel revascularization (TLR/TVR) rates in the BMS control group of these trials were spuriously high. Methods We used meta-analytic techniques to systematically compare clinical event rates among patients treated with BMS in trials where BMS were the experimental (BMSexperimental) rather than the control (BMScontrol) intervention. MEDLINE searches were performed to identify eligible randomized trials comparing either drug-eluting stents with BMScontrol, or BMSexperimental with balloon angioplasty in patients with non-acute coronary artery disease. Trial characteristics and 6 to 12 month rates for death, myocardial infarction, TLR/TVR and major adverse cardiac events (MACE) were extracted and assessed. Results Eligible trials yielded 50 BMS cohorts: 19 in the BMScontrol group (4 046 patients) and 31 in the BMSexperimental group (5 068 patients). Summary death and infarction rates did not differ between groups. The summary TLR/TVR rates were 16.2% (95% confidence interval, CI: 13.5, 19.3) versus 13.8% (95% CI: 12.0, 15.7) in BMScontrol versus BMSexperimental groups, respectively (p=0.15). Among 39 BMS cohorts with ≤250 patients, TLR/TVR rates were significantly higher in BMScontrol versus BMSexperimental groups (18.9% [95% CI: 16.0, 22.2] versus 13.7% [95% CI: 11.5, 16.3], p=0.01). There were no between-group differences among larger BMS cohorts (p=0.98). Conclusions While overall clinical event rates did not differ in the BMScontrol and the BMSexperimental groups, a higher rate of TVR/TLR was seen in the BMScontrol group among smaller trials. PMID:18371468

  19. [Bare Soil Moisture Inversion Model Based on Visible-Shortwave Infrared Reflectance].

    PubMed

    Zheng, Xiao-po; Sun, Yue-jun; Qin, Qi-ming; Ren, Hua-zhong; Gao, Zhong-ling; Wu, Ling; Meng, Qing-ye; Wang, Jin-liang; Wang, Jian-hua

    2015-08-01

    Soil is the loose solum of land surface that can support plants. It consists of minerals, organics, atmosphere, moisture, microbes, et al. Among its complex compositions, soil moisture varies greatly. Therefore, the fast and accurate inversion of soil moisture by using remote sensing is very crucial. In order to reduce the influence of soil type on the retrieval of soil moisture, this paper proposed a normalized spectral slope and absorption index named NSSAI to estimate soil moisture. The modeling of the new index contains several key steps: Firstly, soil samples with different moisture level were artificially prepared, and soil reflectance spectra was consequently measured using spectroradiometer produced by ASD Company. Secondly, the moisture absorption spectral feature located at shortwave wavelengths and the spectral slope of visible wavelengths were calculated after analyzing the regular spectral feature change patterns of different soil at different moisture conditions. Then advantages of the two features at reducing soil types' effects was synthesized to build the NSSAI. Thirdly, a linear relationship between NSSAI and soil moisture was established. The result showed that NSSAI worked better (correlation coefficient is 0.93) than most of other traditional methods in soil moisture extraction. It can weaken the influences caused by soil types at different moisture levels and improve the bare soil moisture inversion accuracy.

  20. Delivery of bone morphogenetic protein-2 and substance P using graphene oxide for bone regeneration

    PubMed Central

    La, Wan-Geun; Jin, Min; Park, Saibom; Yoon, Hee-Hun; Jeong, Gun-Jae; Bhang, Suk Ho; Park, Hoyoung; Char, Kookheon; Kim, Byung-Soo

    2014-01-01

    In this study, we demonstrate that graphene oxide (GO) can be used for the delivery of bone morphogenetic protein-2 (BMP-2) and substance P (SP), and that this delivery promotes bone formation on titanium (Ti) implants that are coated with GO. GO coating on Ti substrate enabled a sustained release of BMP-2. BMP-2 delivery using GO-coated Ti exhibited a higher alkaline phosphatase activity in bone-forming cells in vitro compared with bare Ti. SP, which is known to recruit mesenchymal stem cells (MSCs), was co-delivered using Ti or GO-coated Ti to further promote bone formation. SP induced the migration of MSCs in vitro. The dual delivery of BMP-2 and SP using GO-coated Ti showed the greatest new bone formation on Ti implanted in the mouse calvaria compared with other groups. This approach may be useful to improve osteointegration of Ti in dental or orthopedic implants. PMID:24872706

  1. Free Energy of Bare and Capped Gold Nanoparticles Permeating through a Lipid Bilayer.

    PubMed

    Mhashal, Anil R; Roy, Sudip

    2016-11-04

    Herein, we study the permeation free energy of bare and octane-thiol-capped gold nanoparticles (AuNPs) translocating through a lipid membrane. To investigate this, we have pulled the bare and capped AuNPs from bulk water to the membrane interior and estimated the free energy cost. The adsorption of the bare AuNP on the bilayer surface is energetically favorable but further loading inside it requires energy. However, the estimated free-energy barrier for loading the capped AuNP into the lipid membrane is much higher compared to bare AuNP. We also demonstrate the details of the permeation process of bare and capped AuNPs. Bare AuNP induces the curvature in the lipid membrane whereas capped AuNP creates an opening in the interacting monolayer and get inserted into the membrane. The insertion of capped AuNP induces a partial unzipping of the lipid bilayer, which results in the ordering of the local lipids interacting with the nanoparticle. However, bare AuNP disrupts the lipid membrane by pushing the lipid molecules inside the membrane. We also analyze pore formation due to the insertion of capped AuNP into the membrane, which results in water molecules penetrating the hydrophobic region.

  2. Patterns of long bone growth in a mid-19th century documented sample of the urban poor from Bethnal Green, London, UK.

    PubMed

    Ives, Rachel; Humphrey, Louise

    2017-05-01

    Studies of male and female long bone growth in past populations are limited and usually constrained by the lack of personal identification. This article aimed to evaluate long bone growth in a series of mid-19(th) century documented burials associated with the urban poor from Bethnal Green, London, UK. Maximum diaphyseal lengths from 74 males and 70 females (2 months to 12 years) were compared to modern reference data from North America. Diaphyseal lengths were expressed as a percentage of expected length and an average percentage value was calculated across all available long bones. An index of growth progression was introduced to explore differences in the progress of males and females towards their projected adult size. Deviation from the expected growth attainment was evident in both sexes in the archaeological series by 2-4 months of age. Only 19.4% (28/144) of the children had attained an average long bone length >90% of the predicted mean in the reference series. The percentage of expected growth attainment decreased steadily in both sexes during infancy and early childhood. Overall, females deviated further from their expected growth progression than males. Growth faltering in both males and females was established during infancy (<1 year) with no evidence for recovery in older age groups. Early weaning and inadequate artificial feeding, together with impoverished living conditions and limited sanitary provision, most likely impacted on childhood growth. © 2017 Wiley Periodicals, Inc.

  3. Dynamic weakening of serpentinite gouges and bare surfaces at seismic slip rates.

    PubMed

    Proctor, B P; Mitchell, T M; Hirth, G; Goldsby, D; Zorzi, F; Platt, J D; Di Toro, G

    2014-11-01

    To investigate differences in the frictional behavior between initially bare rock surfaces of serpentinite and powdered serpentinite ("gouge") at subseismic to seismic slip rates, we conducted single-velocity step and multiple-velocity step friction experiments on an antigorite-rich and lizardite-rich serpentinite at slip rates (V) from 0.003 m/s to 6.5 m/s, sliding displacements up to 1.6 m, and normal stresses (σn ) up to 22 MPa for gouge and 97 MPa for bare surfaces. Nominal steady state friction values (μnss) in gouge at V = 1 m/s are larger than in bare surfaces for all σn tested and demonstrate a strong σn dependence; μnss decreased from 0.51 at 4.0 MPa to 0.39 at 22.4 MPa. Conversely, μnss values for bare surfaces remained ∼0.1 with increasing σn and V. Additionally, the velocity at the onset of frictional weakening and the amount of slip prior to weakening were orders of magnitude larger in gouge than in bare surfaces. Extrapolation of the normal stress dependence for μnss suggests that the behavior of antigorite gouge approaches that of bare surfaces at σn ≥ 60 MPa. X-ray diffraction revealed dehydration reaction products in samples that frictionally weakened. Microstructural analysis revealed highly localized slip zones with melt-like textures in some cases gouge experiments and in all bare surfaces experiments for V ≥ 1 m/s. One-dimensional thermal modeling indicates that flash heating causes frictional weakening in both bare surfaces and gouge. Friction values for gouge decrease at higher velocities and after longer displacements than bare surfaces because strain is more distributed.

  4. Mineral bone disorder and its management among hemodialysis patients in the Gulf Cooperation Council: Initial findings from the dialysis outcomes and practice patterns study (2012-2015).

    PubMed

    Al Salmi, Issa; AlRukhaimi, Mona; AlSahow, Ali; Shaheen, Faisal A M; Al-Ghamdi, Saeed M G; AlAli, Fadwa; AlGhareeb, Sumaya; Al Maimani, Yacoub; AlGhonaim, Mohammed; Bieber, Brian; Tentori, Francesca; Pisoni, Ronald L

    2016-11-01

    The prospective cohort Dialysis Outcomes and Practice Patterns Study (DOPPS) initiated data collection in national samples of hemodialysis (HD) units (total of 41 study sites) in all six Gulf Cooperation Council (GCC) countries (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) in late 2012. Here, we report initial results regarding mineral bone disorders (MBDs) and its management in the GCC countries. Forty-one randomly selected HD facilities, treating >23 HD patients each, were sampled and represent care for >95% of GCC HD patients. Descriptive results for the GCC countries based on a random sample of 20-30 HD patients in each study facility. Initial results for the GCC are from 931 HD patients treated at 41 dialysis units (ranging from 1 unit in Bahrain to 21 in Saudi Arabia). Results are presented as weighted estimates, accounting for the sampling fraction in each unit. Baseline descriptive statistics (e.g., mean, median, or percentage), weighted by facility sampling fraction were calculated for the study sample. For analyses examining the percent of facility patients having (a) serum phosphorus >6.0 mg/dL or (b) parathyroid hormone (PTH) >600 pg/mL, analyses were restricted to facilities having at least 10 HD patients with a reported serum phosphorus or PTH measurement, respectively. Logistic regression analyses of the indicated binary outcomes were based on the use of generalized estimating equations and were adjusted for GCC country, patient age category (<45 years, 45-65 years, and >65 years old), sex, and whether the patient was diagnosed with diabetes mellitus. Logistic models accounted for clustering of patients within facilities, assuming an exchangeable working correlation matrix. Mean age of HD patients in the GCC countries was 53 years vs. 61-64 years in the three other DOPPS regions. MBD markers showed slightly lower mean serum Calcium in the GCC countries, similar mean serum phosphorus, and intermediate median PTH levels

  5. Bone tumor

    MedlinePlus

    ... primary bone tumors include: Chondrosarcoma Ewing sarcoma Fibrosarcoma Osteosarcomas Cancers that most often spread to the bone are cancers of the: Breast Kidney Lung Prostate Thyroid These forms of cancer usually affect ...

  6. Bone grafts.

    PubMed

    Hubble, Matthew J W

    2002-09-01

    Bone grafts are used in musculoskeletal surgery to restore structural integrity and enhance osteogenic potential. The demand for bone graft for skeletal reconstruction in bone tumor, revision arthroplasty, and trauma surgery, couple with recent advances in understanding and application of the biology of bone transplantation, has resulted in an exponential increase in the number of bone-grafting procedures performed over the last decade. It is estimated that 1.5 million bone-grafting procedures are currently performed worldwide each year, compared to a fraction of that number 20 years ago. Major developments also have resulted in the harvesting, storage, and use of bone grafts and production of graft derivatives, substitutes, and bone-inducing agents.

  7. Alcohol and bone.

    PubMed

    Mikosch, Peter

    2014-01-01

    Alcohol is widely consumed across the world in different cultural and social settings. Types of alcohol consumption differ between (a) light, only occasional consumption, (b) heavy chronic alcohol consumption, and (c) binge drinking as seen as a new pattern of alcohol consumption among teenagers and young adults. Heavy alcohol consumption is detrimental to many organs and tissues, including bones. Osteoporosis is regularly mentioned as a secondary consequence of alcoholism, and chronic alcohol abuse is established as an independent risk factor for osteoporosis. The review will present the different mechanisms and effects of alcohol intake on bone mass, bone metabolism, and bone strength, including alcoholism-related "life-style factors" such as malnutrition, lack of exercise, and hormonal changes as additional causative factors, which also contribute to the development of osteoporosis due to alcohol abuse.

  8. Bone Analyzer

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The danger of disuse osteoporosis under weightless condition in space led to extensive research into measurements of bone stiffness and mass by the Biomedical Research Division of Ames and Stanford University. Through its Technology Utilization Program, NASA funded an advanced SOBSA, a microprocessor-controlled bone probe system. SOBSA determines bone stiffness by measuring responses to an electromagnetic shaker. With this information, a physician can identify bone disease, measure deterioration and prescribe necessary therapy. The system is now undergoing further testing.

  9. Bone cement

    PubMed Central

    Vaishya, Raju; Chauhan, Mayank; Vaish, Abhishek

    2013-01-01

    The knowledge about the bone cement is of paramount importance to all Orthopaedic surgeons. Although the bone cement had been the gold standard in the field of joint replacement surgery, its use has somewhat decreased because of the advent of press-fit implants which encourages bone in growth. The shortcomings, side effects and toxicity of the bone cement are being addressed recently. More research is needed and continues in the field of nanoparticle additives, enhanced bone–cement interface etc. PMID:26403875

  10. Bone Infections

    MedlinePlus

    ... bloodstream. People who are at risk for bone infections include those with diabetes, poor circulation, or recent injury to the bone. You may also be at risk if you are having hemodialysis. Symptoms of bone infections include Pain in the infected area Chills and ...

  11. Bone remodeling after renal transplantation.

    PubMed

    Bellorin-Font, Ezequiel; Rojas, Eudocia; Carlini, Raul G; Suniaga, Orlando; Weisinger, José R

    2003-06-01

    Several studies have indicated that bone alterations after transplantation are heterogeneous. Short-term studies after transplantation have shown that many patients exhibit a pattern consistent with adynamic bone disease. In contrast, patients with long-term renal transplantation show a more heterogeneous picture. Thus, while adynamic bone disease has also been described in these patients, most studies show decreased bone formation and prolonged mineralization lag-time faced with persisting bone resorption, and even clear evidence of generalized or focal osteomalacia in many patients. Thus, the main alterations in bone remodeling are a decrease in bone formation and mineralization up against persistent bone resorption, suggesting defective osteoblast function, decreased osteoblastogenesis, or increased osteoblast death rates. Indeed, recent studies from our laboratory have demonstrated that there is an early decrease in osteoblast number and surfaces, as well as in reduced bone formation rate and delayed mineralization after transplantation. These alterations are associated with an early increase in osteoblast apoptosis that correlates with low levels of serum phosphorus. These changes were more frequently observed in patients with low turnover bone disease. In contrast, PTH seemed to preserve osteoblast survival. The mechanisms of hypophosphatemia in these patients appear to be independent of PTH, suggesting that other phosphaturic factors may play a role. However, further studies are needed to determine the nature of a phosphaturic factor and its relationship to the alterations of bone remodeling after transplantation.

  12. 30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 75.1003 Section 75.1003... Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and trolley feeder wires. Trolley wires, trolley feeder wires, and bare signal wires shall be insulated...

  13. 30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 77.1802 Section 77.1802... Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare..., and bare signal wires shall be adequately guarded: (a) At all points where men are required to work or...

  14. Exploiting Defect Clustering to Screen Bare Die for Infant Mortality Failure: An Experimental Study

    NASA Technical Reports Server (NTRS)

    Lakin, David R., II; Singh, Adit D.

    1999-01-01

    We present the first experimental results to establish that a binning strategy based on defect clustering can be used to screen bare die for early life failures. The data for this study comes from the SEMATECH test methods experiment.

  15. Exploiting Defect Clustering to Screen Bare Die for Infant Mortality Failure: An Experimental Study

    NASA Technical Reports Server (NTRS)

    Lakin, David R., II; Singh, Adit D.

    1999-01-01

    We present the first experimental results to establish that a binning strategy based on defect clustering can be used to screen bare die for early life failures. The data for this study comes from the SEMATECH test methods experiment.

  16. Bone Densitometry (Bone Density Scan)

    MedlinePlus

    ... In some communities, a CT scan with special software can also be used to diagnose or monitor ... patient's bone mineral density. DEXA machines feature special software that compute and display the bone density measurements ...

  17. Dynamic weakening of serpentinite gouges and bare surfaces at seismic slip rates

    PubMed Central

    Proctor, B P; Mitchell, T M; Hirth, G; Goldsby, D; Zorzi, F; Platt, J D; Di Toro, G

    2014-01-01

    To investigate differences in the frictional behavior between initially bare rock surfaces of serpentinite and powdered serpentinite (“gouge”) at subseismic to seismic slip rates, we conducted single-velocity step and multiple-velocity step friction experiments on an antigorite-rich and lizardite-rich serpentinite at slip rates (V) from 0.003 m/s to 6.5 m/s, sliding displacements up to 1.6 m, and normal stresses (σn) up to 22 MPa for gouge and 97 MPa for bare surfaces. Nominal steady state friction values (μnss) in gouge at V = 1 m/s are larger than in bare surfaces for all σn tested and demonstrate a strong σn dependence; μnss decreased from 0.51 at 4.0 MPa to 0.39 at 22.4 MPa. Conversely, μnss values for bare surfaces remained ∼0.1 with increasing σn and V. Additionally, the velocity at the onset of frictional weakening and the amount of slip prior to weakening were orders of magnitude larger in gouge than in bare surfaces. Extrapolation of the normal stress dependence for μnss suggests that the behavior of antigorite gouge approaches that of bare surfaces at σn ≥ 60 MPa. X-ray diffraction revealed dehydration reaction products in samples that frictionally weakened. Microstructural analysis revealed highly localized slip zones with melt-like textures in some cases gouge experiments and in all bare surfaces experiments for V ≥ 1 m/s. One-dimensional thermal modeling indicates that flash heating causes frictional weakening in both bare surfaces and gouge. Friction values for gouge decrease at higher velocities and after longer displacements than bare surfaces because strain is more distributed. Key Points Gouge friction approaches that of bare surfaces at high normal stress Dehydration reactions and bulk melting in serpentinite in < 1 m of slip Flash heating causes dynamic frictional weakening in gouge and bare surfaces PMID:26167425

  18. Malignant lymphoma of bone.

    PubMed

    Dürr, Hans Roland; Müller, Peter Ernst; Hiller, Erhard; Maier, Markus; Baur, Andrea; Jansson, Volkmar; Refior, Hans Jürgen

    2002-02-01

    Malignant lymphoma of bone is rare. In many cases, its diagnosis is delayed because of unspecific clinical signs and equivocal radiographs. Therapy in general is multimodal, including surgery and radio- and chemotherapy. Our objective was to demonstrate the clinical and radiological aspects of the lesion to optimize diagnostic approaches and to evaluate treatment and prognostic factors. Thirty-six patients with malignant lymphoma of bone who were surgically treated over a 15-year-period were retrospectively reviewed. Seventeen of them showed a singular bone non-Hodgkin's lymphoma (NHL) which was classified as primary lymphoma of the bone (PLB). In 13 cases, dissemination of the disease with multiple bone or visceral involvement was apparent (dNHL). Six patients suffered from bone involvement due to Hodgkin's disease (HD). Surgical treatment was indicated for diagnostic reasons or complications due to the disease. Radiation and chemotherapy were part of the oncological treatment. The patients' mean age was 57 years. The main symptom in malignant bone lymphoma in 33 patients was pain, with an average duration of 8 months. In the secondary cases, bone involvement appeared on average 57 months after the initial diagnosis. An osteolytic pattern was seen in 58% of the lesions. Soft-tissue involvement was seen in 71% of cases (PLB 80%, dNHL 73%, HD 40%) and was the primary diagnostic sign associated with this disease. The 5-year survival rate was 61% (PLB 88%, dNHL 38%, HD 50%). Multiple vs solitary bone involvement was the most significant factor in the prognosis. Extraskeletal involvement significantly decreased survival. No correlation was found between gender, age, location, or histological subtypes and survival. Bone involvement in NHL appears late in the extraskeletal disease. The clinical appearance is nonspecific, and the delay between the onset of symptoms and diagnosis is often long. One of the major radiologic signs is the existence of a soft-tissue tumor

  19. Growth and bone development.

    PubMed

    Cooper, Cyrus; Harvey, Nicholas; Javaid, Kassim; Hanson, Mark; Dennison, Elaine

    2008-01-01

    Osteoporosis is a major cause of morbidity and mortality through its association with age-related fractures. Although most effort in fracture prevention has been directed at retarding the rate of age-related bone loss, and reducing the frequency and severity of trauma among elderly people, evidence is growing that peak bone mass is an important contributor to bone strength during later life. The normal patterns of skeletal growth have been well characterized in cross-sectional and longitudinal studies. It has been confirmed that boys have higher bone mineral content, but not volumetric bone density, than girls. Furthermore, there is a dissociation between the peak velocities for height gain and bone mineral accrual, in both genders. Puberty is the period during which volumetric density appears to increase in both axial and appendicular sites. Many factors influence the accumulation of bone mineral during childhood and adolescence, including heredity, gender, diet, physical activity, endocrine status, and sporadic risk factors such as cigarette smoking. In addition to these modifiable factors during childhood, evidence has also accrued that fracture risk might be programmed during intrauterine life. Epidemiological studies have demonstrated a relationship between birthweight, weight in infancy, and adult bone mass. This appears to be mediated through modulation of the set-point for basal activity of pituitary-dependent endocrine systems such as the hypothalamicpituitary-adrenal and growth hormone/insulin-like growth factor-1 axes. Maternal smoking, diet (particularly vitamin D deficiency), and physical activity also appear to modulate bone mineral acquisition during intrauterine life; furthermore, both low birth size and poor childhood growth are directly linked to the later risk of hip fracture. The optimization of maternal nutrition and intrauterine growth should also be included within preventive strategies against osteoporotic fracture, albeit for future

  20. Bone poroelasticity.

    PubMed

    Cowin, S C

    1999-03-01

    Poroelasticity is a well-developed theory for the interaction of fluid and solid phases of a fluid-saturated porous medium. It is widely used in geomechanics and has been applied to bone by many authors in the last 30 years. The purpose of this work is, first, to review the literature related to the application of poroelasticity to the interstitial bone fluid and, second, to describe the specific physical and modeling considerations that establish poroelasticity as an effective and useful model for deformation-driven bone fluid movement in bone tissue. The application of poroelasticity to bone differs from its application to soft tissues in two important ways. First, the deformations of bone are small while those of soft tissues are generally large. Second, the bulk modulus of the mineralized bone matrix is about six times stiffer than that of the fluid in the pores while the bulk moduli of the soft tissue matrix and the pore water are almost the same. Poroelasticity and electrokinetics can be used to explain strain-generated potentials in wet bone. It is noted that strain-generated potentials can be used as an effective tool in the experimental study of local bone fluid flow, and that the knowledge of this technique will contribute to the answers of a number of questions concerning bone mineralization, osteocyte nutrition and the bone mechanosensory system.

  1. [Bone substitutes].

    PubMed

    Jordana, Fabienne; Le Visage, Catherine; Weiss, Pierre

    2017-01-01

    Bone substitutes, used to fill a defect after a surgery or a trauma, provide a mechanical support and might induce bone healing. They constitute an alternative to autogenous bone grafts, the 'gold standard' which remains the reference despite its risk of postoperative complications. The clinician choice of a bone substitute is based on the required bone volume, the handling (injectability, malleability) and mechanical properties (setting time, viscosity, resorbability among others) of the material. Bone substitutes are commonly used in orthopedic surgery, neurosurgery, stomatology and dental applications. Their use increases steadily, with the recent clinical development of injectable forms. In addition, novel technologies by subtractive or additive techniques allow today the production of controlled architecture materials. Here, we present a bone substitutes classification according to their origin (natural or synthetic) and chemical composition, and the most common use of these substitutes. © 2017 médecine/sciences – Inserm.

  2. Multiple roles of Activin/Nodal, bone morphogenetic protein, fibroblast growth factor and Wnt/β-catenin signalling in the anterior neural patterning of adherent human embryonic stem cell cultures

    PubMed Central

    Lupo, Giuseppe; Novorol, Claire; Smith, Joseph R.; Vallier, Ludovic; Miranda, Elena; Alexander, Morgan; Biagioni, Stefano; Pedersen, Roger A.; Harris, William A.

    2013-01-01

    Several studies have successfully produced a variety of neural cell types from human embryonic stem cells (hESCs), but there has been limited systematic analysis of how different regional identities are established using well-defined differentiation conditions. We have used adherent, chemically defined cultures to analyse the roles of Activin/Nodal, bone morphogenetic protein (BMP), fibroblast growth factor (FGF) and Wnt/β-catenin signalling in neural induction, anteroposterior patterning and eye field specification in hESCs. We show that either BMP inhibition or activation of FGF signalling is required for effective neural induction, but these two pathways have distinct outcomes on rostrocaudal patterning. While BMP inhibition leads to specification of forebrain/midbrain positional identities, FGF-dependent neural induction is associated with strong posteriorization towards hindbrain/spinal cord fates. We also demonstrate that Wnt/β-catenin signalling is activated during neural induction and promotes acquisition of neural fates posterior to forebrain. Therefore, inhibition of this pathway is needed for efficient forebrain specification. Finally, we provide evidence that the levels of Activin/Nodal and BMP signalling have a marked influence on further forebrain patterning and that constitutive inhibition of these pathways represses expression of eye field genes. These results show that the key mechanisms controlling neural patterning in model vertebrate species are preserved in adherent, chemically defined hESC cultures and reveal new insights into the signals regulating eye field specification. PMID:23576785

  3. Updates in biological therapies for knee injuries: bone.

    PubMed

    Kfuri, Mauricio; de Freitas, Rafael Lara; Batista, Bruno Bellaguarda; Salim, Rodrigo; Castiglia, Marcello Teixeira; Tavares, Ricardo Antonio; Araújo, Paulo Henrique

    2014-09-01

    Bone is a unique tissue because of its mechanical properties, ability for self-repair, and enrollment in different metabolic processes such as calcium homeostasis and hematopoietic cell production. Bone barely tolerates deformation and tends to fail when overloaded. Fracture healing is a complex process that in particular cases is impaired. Osteoprogenitor cells proliferation, growth factors, and a sound tridimensional scaffold at fracture site are key elements for new bone formation and deposition. Mechanical stability and ample vascularity are also of great importance on providing a proper environment for bone healing. From mesenchymal stem cells delivery to custom-made synthetic scaffolds, many are the biological attempts to enhance bone healing. Impaired fracture healing represents a real burden to contemporary society. Sound basic science knowledge has contributed to newer approaches aimed to accelerate and improve the quality of bone healing.

  4. Bone Metastases in Castration-Resistant Prostate Cancer: Associations between Morphologic CT Patterns, Glycolytic Activity, and Androgen Receptor Expression on PET and Overall Survival

    PubMed Central

    Wassberg, Cecilia; Fox, Josef J.; Wibmer, Andreas; Goldman, Debra A.; Kuk, Deborah; Gonen, Mithat; Larson, Steven M.; Morris, Michael J.; Scher, Howard I.; Hricak, Hedvig

    2014-01-01

    Purpose To compare the features of bone metastases at computed tomography (CT) to tracer uptake at fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) and fluorine 18 16β-fluoro-5-dihydrotestosterone (FDHT) PET and to determine associations between these imaging features and overall survival in men with castration-resistant prostate cancer. Materials and Methods This is a retrospective study of 38 patients with castration-resistant prostate cancer. Two readers independently evaluated CT, FDG PET, and FDHT PET features of bone metastases. Associations between imaging findings and overall survival were determined by using univariate Cox proportional hazards regression. Results In 38 patients, reader 1 detected 881 lesions and reader 2 detected 867 lesions. Attenuation coefficients at CT correlated inversely with FDG (reader 1: r = −0.3007; P < .001; reader 2: r = −0.3147; P < .001) and FDHT (reader 1: r = −0.2680; P = .001; reader 2: r = −0.3656; P < .001) uptake. The number of lesions on CT scans was significantly associated with overall survival (reader 1: hazard ratio [HR], 1.025; P = .05; reader 2: HR, 1.021; P = .04). The numbers of lesions on FDG and FDHT PET scans were significantly associated with overall survival for reader 1 (HR, 1.051–1.109; P < .001) and reader 2 (HR, 1.026–1.082; P ≤ .009). Patients with higher FDHT uptake (lesion with the highest maximum standardized uptake value) had significantly shorter overall survival (reader 1: HR, 1.078; P = .02; reader 2: HR, 1.092; P = .02). FDG uptake intensity was not associated with overall survival (reader 1, P = .65; reader 2, P = .38). Conclusion In patients with castration-resistant prostate cancer, numbers of bone lesions on CT, FDG PET, and FDHT PET scans and the intensity of FDHT uptake are significantly associated with overall survival. © RSNA, 2013 PMID:24475817

  5. Scintigraphy of aneurysmal bone cysts

    SciTech Connect

    Hudson, T.M.

    1984-04-01

    Bone scintigrams with Tc-99m radiopharmaceuticals of 25 aneurysmal bone cysts showed abnormal activity in every case. In 22 cases, the activity was correlated with the true pathologic extent of the lesions; only three exhibited a false-positive extended pattern of uptake beyond the true tumor margins. Sixteen scintigrams (64%) revealed increased uptake, chiefly around the periphery of the lesions, with less activity in their centers. This feature could not be explained simply by the cystic nature of the lesions, since aneurysmal bone cysts may contain considerable fibrous tissue septa containing trabeculae of reactive new bone. However, there was no correlation between any specific anatomic or histologic pattern and the intensity and pattern of abnormal scintigraphic activity.

  6. Bone cutting.

    PubMed

    Giraud, J Y; Villemin, S; Darmana, R; Cahuzac, J P; Autefage, A; Morucci, J P

    1991-02-01

    Bone cutting has always been a problem for surgeons because bone is a hard living material, and many osteotomes are still very crude tools. Technical improvement of these surgical tools has first been their motorization. Studies of the bone cutting process have indicated better features for conventional tools. Several non-conventional osteotomes, particularly ultrasonic osteotomes are described. Some studies on the possible use of lasers for bone cutting are also reported. Use of a pressurised water jet is also briefly examined. Despite their advantages, non-conventional tools still require improvement if they are to be used by surgeons.

  7. [Bone diseases].

    PubMed

    Uebelhart, Brigitte; Rizzoli, René

    2016-01-13

    Calcium intake shows a small impact on bone mineral density and fracture risk. Denosumab is a more potent inhibitor of bone resorption than zoledronate. Abaloparatide, PTHrP analog, increases bone mineral density and decreases fracture incidence. Teriparatide could be delivered via a transdermic device. Romosozumab and odanacatib improve calculated bone strength. Sequential or combined treatments with denosumab and teriparatide could be of interest, but not denosumab followed by teriparatide. Fibrous dysplasia, Paget disease and hypophosphatasia are updated, as well as atypical femoral fracture and osteonecrosis of the jaw.

  8. Effect of swift heavy ion irradiation on bare and coated ZnS quantum dots

    SciTech Connect

    Chowdhury, S. Hussain, A.M.P.; Ahmed, G.A.; Singh, F.; Avasthi, D.K.; Choudhury, A.

    2008-12-01

    The present study compares structural and optical modifications of bare and silica (SiO{sub 2}) coated ZnS quantum dots under swift heavy ion (SHI) irradiation. Bare and silica coated ZnS quantum dots were prepared following an inexpensive chemical route using polyvinyl alcohol (PVA) as the dielectric host matrix. X-ray diffraction (XRD) and transmission electron microscopy (TEM) study of the samples show the formation of almost spherical ZnS quantum dots. The UV-Vis absorption spectra reveal blue shift relative to bulk material in absorption energy while photoluminescence (PL) spectra suggests that surface state and near band edge emissions are dominating in case of bare and coated samples, respectively. Swift heavy ion irradiation of the samples was carried out with 160 MeV Ni{sup 12+} ion beam with fluences 10{sup 12} to 10{sup 13} ions/cm{sup 2}. Size enhancement of bare quantum dots after irradiation has been indicated in XRD and TEM analysis of the samples which has also been supported by optical absorption spectra. However similar investigations on irradiated coated quantum dots revealed little change in quantum dot size and emission. The present study thus shows that the coated ZnS quantum dots are stable upon SHI irradiation compared to the bare one.

  9. Dynamics of indigenous microbial populations of butter head lettuce grown in mulch and on bare soil.

    PubMed

    Ponce, A G; Agüero, M V; Roura, S I; Del Valle, C E; Moreira, M R

    2008-08-01

    The native microflora of lettuce cultivated in mulch and on bare soil and its evolution during storage at optimal condition were evaluated. Inner, mid, and outer leaves of the lettuce heads were analyzed separately and the evolution of the microbial populations were fitted to Gompertz and logistic models. The cultivation method (bare soil and mulch) introduced differences in the initial counts, evolution, and tolerance to refrigeration temperatures for some of the microbial populations under study. Most microbial populations from mulch lettuce presented a decline or little growth under refrigerated storage. However, populations from bare soil lettuce presented some growth phase during storage. Lactic acid bacteria from bare soil lettuce presented significant growth after 8 d of storage while LAB from mulch grown lettuce did not. Concurrently with the LAB growth, there was a decline in the coliform counts in bare soil grown lettuce. At the end of storage, the inner and mid leaves of mulch lettuce presented lower counts of psychrotrophic bacteria, LAB, and yeast and molds.

  10. The Life Cycle of Bare Branch Families in China---A Simulation Study

    PubMed Central

    JIANG, Quanbao; GUO, Zhen; LI, Shuzhuo; FELDMAN, Marcus W.

    2013-01-01

    China is and will be characterized by a large number of men who are unable to marry: these men are often referred to as “bare branches.” In this paper we define the bare branch family and divide its life cycle into three stages: the unmarried co-resident with both parents, co-resident with a surviving parent, and living alone. Using life tables and probability methods, we find that up to age 60, the bare branch male faces cumulative probabilities of 0.8 and 0.6, for his father's and mother's death, respectively. The definition of the age at which bare branch status is initialized influences the length of these stages. As the childbearing age of parents increases, the age of a bare branch at the death of his parents decreases, and the duration of his living alone lengthens. An increase in the mother's childbearing age, holding that of the father constant, shortens the stage of co-residence with both parents, and lengthens the stage of living alone. PMID:24174704

  11. A prospective randomized study for efficacy of an uncovered double bare metal stent compared to a single bare metal stent in malignant biliary obstruction.

    PubMed

    Lee, Hyun Jik; Chung, Moon Jae; Park, Jeong Yup; Park, Seung Woo; Nam, Chung Mo; Song, Si Young; Bang, Seungmin

    2017-08-01

    A biliary self-expandable metal stent (SEMS) is commonly used to relieve malignant biliary obstruction. The aim of this study was to compare the efficacy of a conventional uncovered SEMS with that of a newly developed uncovered double bare metal stent in reducing the risk of stent occlusion caused by tumor ingrowth. We performed a prospective, open-labeled, randomized trial in 71 patients at Severance Hospital, Yonsei University College of Medicine from June 2013 to June 2014. Patients with inoperable malignant biliary obstruction were included and randomized to receive an uncovered single bare metal stent (SBSs; S&G Biotech Inc.), an uncovered single bare metal stent (SBSt; Taewoong Medical), or an uncovered double bare metal stent (DBS; S&G Biotech Inc.). The mean age was 66.6 years (range, 35-83), and 42 (59.2%) were male. The mean duration of stent patency was 212 days (±152) in the DBS group (n = 24) compared with 124 days (±98) in the SBSs group (n = 23; P = 0.022 for noninferiority) and 116 days (±79) in the SBSt group (n = 24; P = 0.010 for noninferiority). There were no differences in the incidences of early and delayed complications or migration. The newly developed DBS is noninferior to the conventional uncovered SEMSs on duration of stent patency and tumor ingrowth occurred less frequently in the DBS group. This might decrease the need for reintervention and offer a better quality of life. The trial is registered with Clinicaltrials.gov no: NCT01869894.

  12. Adipose- and bone marrow-derived mesenchymal stem cells display different osteogenic differentiation patterns in 3D bioactive glass-based scaffolds.

    PubMed

    Rath, Subha N; Nooeaid, Patcharakamon; Arkudas, Andreas; Beier, Justus P; Strobel, Leonie A; Brandl, Andreas; Roether, Judith A; Horch, Raymund E; Boccaccini, Aldo R; Kneser, Ulrich

    2016-10-01

    Mesenchymal stem cells can be isolated from a variety of different sources, each having their own peculiar merits and drawbacks. Although a number of studies have been conducted comparing these stem cells for their osteo-differentiation ability, these are mostly done in culture plastics. We have selected stem cells from either adipose tissue (ADSCs) or bone marrow (BMSCs) and studied their differentiation ability in highly porous three-dimensional (3D) 45S5 Bioglass®-based scaffolds. Equal numbers of cells were seeded onto 5 × 5 × 4 mm(3) scaffolds and cultured in vitro, with or without osteo-induction medium. After 2 and 4 weeks, the cell-scaffold constructs were analysed for cell number, cell spreading, viability, alkaline phosphatase activity and osteogenic gene expression. The scaffolds with ADSCs displayed osteo-differentiation even without osteo-induction medium; however, with osteo-induction medium osteogenic differentiation was further increased. In contrast, the scaffolds with BMSCs showed no osteo-differentiation without osteo-induction medium; after application of osteo-induction medium, osteo-differentiation was confirmed, although lower than in scaffolds with ADSCs. In general, stem cells in 3D bioactive glass scaffolds differentiated better than cells in culture plastics with respect to their ALP content and osteogenic gene expression. In summary, 45S5 Bioglass-based scaffolds seeded with ADSCs are well-suited for possible bone tissue-engineering applications. Induction of osteogenic differentiation appears unnecessary prior to implantation in this specific setting. Copyright © 2013 John Wiley & Sons, Ltd.

  13. Degradation pattern of porous CaCO3 and hydroxyapatite microspheres in vitro and in vivo for potential application in bone tissue engineering.

    PubMed

    Zhong, Qiwei; Li, Wenhua; Su, Xiuping; Li, Geng; Zhou, Ying; Kundu, Subhas C; Yao, Juming; Cai, Yurong

    2016-07-01

    Despite superior clinical handling, excellent biocompatibility, biodegradation property of calcium phosphate needs to be improved to coincide with the rate of new bone formation. In this study, spherical CaCO3 are fabricated in the presence of the silk sericin and then transformed into porous hydroxyapatite (HAP) microspheres via hydrothermal method. The degradation behavior of obtained CaCO3, HAP and their mixture is first investigated in vitro. The result demonstrates that the weight loss of HAP microspheres are almost 24.3% after immersing in pH 7.40 Tris-HCl buffer solution for 12 weeks, which is far slower than that of spherical CaCO3 (97.5%). The degradation speed of the mixtures depends on the proportion of CaCO3 and HAP. The mixture with higher content of CaCO3 possesses a quicker degradation speed. The obtained CaCO3 and HAP microspheres are injected into subcutaneous tissue of ICR mice with the assistance of sodium alginate. The result in vivo also shows an obvious difference of degradation speed between the obtained CaCO3 and HAP microspheres, implying it is feasible to modulate the degradation property of the mixture through changing the proportion of CaCO3 and HAP The good cytocompatibility of the two kinds of microspheres is proved and a mild inflammation response is observed only at early stage of implantation. The job offers a simple method to modify the degradation properties of biomaterial for potential use in bone tissue engineering.

  14. Talking Bones.

    ERIC Educational Resources Information Center

    Johnson, Jaclyn; Kassing, Sharon

    2002-01-01

    Describes cooperation with the Saint Louis Zoo to provide opportunities for elementary school students to learn about bones, how animals move, what they eat, and how much they grow. Uses biofacts which include bones, skulls, and other parts to make the laboratory a hands-on experience for students. (YDS)

  15. Talking Bones.

    ERIC Educational Resources Information Center

    Johnson, Jaclyn; Kassing, Sharon

    2002-01-01

    Describes cooperation with the Saint Louis Zoo to provide opportunities for elementary school students to learn about bones, how animals move, what they eat, and how much they grow. Uses biofacts which include bones, skulls, and other parts to make the laboratory a hands-on experience for students. (YDS)

  16. Patches of bare ground as a staple commodity for declining ground-foraging insectivorous farmland birds.

    PubMed

    Schaub, Michael; Martinez, Nicolas; Tagmann-Ioset, Aline; Weisshaupt, Nadja; Maurer, Melanie L; Reichlin, Thomas S; Abadi, Fitsum; Zbinden, Niklaus; Jenni, Lukas; Arlettaz, Raphaël

    2010-10-06

    Conceived to combat widescale biodiversity erosion in farmland, agri-environment schemes have largely failed to deliver their promises despite massive financial support. While several common species have shown to react positively to existing measures, rare species have continued to decline in most European countries. Of particular concern is the status of insectivorous farmland birds that forage on the ground. We modelled the foraging habitat preferences of four declining insectivorous bird species (hoopoe, wryneck, woodlark, common redstart) inhabiting fruit tree plantations, orchards and vineyards. All species preferred foraging in habitat mosaics consisting of patches of grass and bare ground, with an optimal, species-specific bare ground coverage of 30-70% at the foraging patch scale. In the study areas, birds thrived in intensively cultivated farmland where such ground vegetation mosaics existed. Not promoted by conventional agri-environment schemes until now, patches of bare ground should be implemented throughout grassland in order to prevent further decline of insectivorous farmland birds.

  17. Evaluating the impacts of re-vegetation of bare peat on blanket peat water tables

    NASA Astrophysics Data System (ADS)

    Shuttleworth, Emma; Richards, Rebecca; Evans, Martin; Agnew, Clive; Pilkington, Mike; Maskill, Rachael; Allott, Tim

    2015-04-01

    Studies of the hydrological impacts of peat restoration in blanket peat systems have focused on the impacts of drain and gully blocking on water tables. However, in the South Pennines of the UK large areas of previously bare blanket peat have been restored by re-vegetation. The effects of this restoration treatment on water table behaviour have not been fully evaluated. Preliminary data from space-for-time studies indicate that re-vegetation leads to significant rises in water tables and decreases in water table variability. Here we present additional data from a before-after-control-intervention (BACI) study to validate these preliminary observations. We also present meteorological, net radiation and evapotranspiration data to test the hypothesis that water table changes associated with re-vegetation are driven by changing evapotranspiration rates as bare peat surfaces re-vegetate. The wider ecosystem service benefits of water table increases associated with re-vegetation of bare peat are discussed.

  18. Estimating Vegetation Height and Bare-Earth Topography from SRTM Data using Fourier Spectral Decomposition

    NASA Astrophysics Data System (ADS)

    Gangodagamage, C.; Liu, D.; Alsdorf, D.

    2010-12-01

    In this study, LiDAR vegetation topography (bare-earth + vegetation height), LiDAR bare-earth topography, the National Elevation Data (NED) set, and Shuttle Radar Terrain Mission (SRTM) measurements are used to develop a statistical model to explore the possibility of extracting vegetation height measurements and accurate high resolution bare-earth topography from SRTM data. The key innovation is to obtain the statistical signature of the vegetation height measurements in the Fourier domain by taking advantage of the well-known linearity in additive properties of the Fourier transform. We demonstrate that the power-law relationship, P(k) α k^(-β), as shown by the bare-earth topography, breaks down approximately at a cross-over wavenumber, k=k_c, due to the vegetation height effect using four different topographic and vegetation study locations in the United States. We document that the vegetation effect mainly dominates the high-frequency contents of the vegetation topography from 2-180 m, 1-60 m, and 1-70 m for the South Fork Eel River, California; Flathead Lake, Montana; and Tenderfoot Creek, Montana, LiDAR data, respectively, and from 1-240 m for 30 m SRTM data for the Jesup, Georgia site. Finally, we demonstrate our ability to obtain a high resolution bare-earth topography with RMSE of 9.6 m, 2.2 m, and 2.9 m and vegetation height with RMSE of 11.0 m (11% error), 4.5 m (12% error), and 1.6 m (8% error) for LiDAR data study sites, whereas for the SRTM data, bare-earth topography and vegetation height are obtained with RMSE values of 5.4 m and 3.1 m, respectively, for the Jesup site. Model Vegetation height

  19. Criticality analysis for weapon disassembly at the Pantex Plant - part I: Bare pits

    SciTech Connect

    Knief, R.A.

    1997-06-01

    This paper briefly describes criticality investigations for weapon assembly and dismantlement at the Pantex Plant. Results are summarized for calculations performed for safety analyses, radiological hazards assessments, and a study to justify the criticality alarm exemption. Pits and pits in containers were modeled in their most reactive configuration. Criticality calculations were performed with the KENO and MCNP code packages. Configurations involving bare pits were subcritical by a substantial amount even with very conservative model assumptions. Thus, it is concluded that a critical configuration involving the bare pits is not credible.

  20. Bare Fiber Bragg Gratings embedded into concrete buffer Supercontainer concept for nuclear waste storage

    SciTech Connect

    Kinet, Damien; Chah, Karima; Megret, Patrice; Caucheteur, Christophe; Gusarov, Andrei; Faustov, Alexey; Areias, Lou

    2015-07-01

    We present the preliminary results obtained with bare fiber Bragg grating-based sensors embedded into half-scale Belgian Supercontainer concept. Being temperature and strain sensitive, some sensors were placed into aluminum tubes to monitor only temperature and results were compared with thermocouples data. The utility of using bare fiber Bragg gratings, knowing that these ones are very fragile, is to have a direct contact between the high alkaline environment of the concrete and silica fibers and to determine its impact over a very long time. (authors)

  1. Bare Stent Implantation in Iatrogenic Dissecting Pseudoaneurysm of the Superior Mesenteric Artery

    SciTech Connect

    Kutlu, Ramazan Ara, Cengiz; Sarac, Kaya

    2007-02-15

    Iatrogenic arterial dissection leading to the development of dissecting pseudoaneurysms of the superior mesenteric artery (SMA) is a rare complication of angiography. Surgical and endovascular treatment options exist for this important condition. We report a case of bare stent implantation in dissecting pseudoaneurysm of the SMA that developed after angiography in a patient with acute mesenteric ischemia. Although it is rarely published, iatrogenic arterial dissection causing pseudoaneurysm can occur after diagnostic and interventional angiography. Bare stent implantation in dissecting pseudoaneurysm of the SMA could be an advantageous endovascular treatment option in selected cases due its to potential preservation of important side branches of the SMA.

  2. Drinking water fluoridation and bone.

    PubMed

    Allolio, B; Lehmann, R

    1999-01-01

    Drinking water fluoridation has an established role in the prevention of dental caries, but may also positively or negatively affect bone. In bone fluoride is incorporated into hydroxylapatite to form the less soluble fluoroapatite. In higher concentrations fluoride stimulates osteoblast activity leading to an increase in cancellous bone mass. As optimal drinking water fluoridation (1 mg/l) is widely used, it is of great interest, whether long-term exposition to artificial water fluoridation has any impact on bone strength, bone mass, and -- most importantly -- fracture rate. Animal studies suggest a biphasic pattern of the effect of drinking water fluoridation on bone strength with a peak strength at a bone fluoride content of 1200 ppm followed by a decline at higher concentrations eventually leading to impaired bone quality. These changes are not paralleled by changes in bone mass suggesting that fluoride concentrations remain below the threshold level required for activation of osteoblast activity. Accordingly, in most epidemiological studies in humans bone mass was not altered by optimal drinking water fluoridation. In contrast, studies on the effect on hip fracture rate gave conflicting results ranging from an increased fracture incidence to no effect, and to a decreased fracture rate. As only ecological studies have been performed, they may be biased by unknown confounding factors -- the so-called ecological fallacy. However, the combined results of these studies indicate that any increase or decrease in fracture rate is likely to be small. It has been calculated that appropriately designed cohort studies to solve the problem require a sample size of >400,000 subjects. Such studies will not be performed in the foreseeable future. Future investigations in humans should, therefore, concentrate on the effect of long-term drinking water fluoridation on bone fluoride content and bone strength.

  3. Low-fat, increased fruit, vegetable, and grain dietary pattern, fractures, and bone mineral density: the Women's Health Initiative Dietary Modification Trial123

    PubMed Central

    Wactawski-Wende, Jean; Wu, LieLing; Rodabough, Rebecca J; Watts, Nelson B; Tylavsky, Frances; Freeman, Ruth; Hendrix, Susan; Jackson, Rebecca

    2009-01-01

    Background: The effects of dietary changes on osteoporosis, low bone density, and frequent falls are unestablished. Objective: We assessed the effect of the Women's Health Initiative Dietary Modification low-fat and increased fruit, vegetable, and grain intervention on incident hip, total, and site-specific fractures and self-reported falls, and, in a subset, on bone mineral density (BMD). Design: Postmenopausal women (n = 48,835) aged 50–79 y (18.6% of minority race-ethnicity) were randomly assigned to receive the Dietary Modification intervention (40%, n = 19,541) (daily goal: ≤20% of energy as fat, ≥5 servings of vegetables and fruit, and ≥6 servings of grains) or to a comparison group that received no dietary changes (60%; n = 29,294). Results: After a mean 8.1 y of follow-up, 215 women in the intervention group and 285 women in the comparison group (annualized rate: 0.14% and 0.12%, respectively) experienced a hip fracture (hazard ratio: 1.12; 95% CI: 0.94, 1.34; P = 0.21). The intervention group (n = 5423; annualized rate: 3.44%) had a lower rate of reporting ≥2 falls than did the comparison group (n = 8695; annualized rate: 3.67%) (HR: 0.92; 95% CI: 0.89, 0.96; P < 0.01). There was a significant interaction according to hormone therapy use; those in the comparison group receiving hormone therapy had the lowest incidence of hip fracture. In a subset of 3951 women, hip BMD at years 3, 6, and 9 was 0.4–0.5% lower in the intervention group than in the comparison group (P = 0.003). Conclusions: A low-fat and increased fruit, vegetable, and grain diet intervention modestly reduced the risk of multiple falls and slightly lowered hip BMD but did not change the risk of osteoporotic fractures. This trial was registered at clinicaltrials.gov as NCT00000611. PMID:19403636

  4. Microgravity and bone cell mechanosensitivity

    NASA Astrophysics Data System (ADS)

    Klein-Nulend, J.; Bacabac, R. G.; Veldhuijzen, J. P.; Van Loon, J. J. W. A.

    2003-10-01

    The capacity of bone tissue to alter its mass and structure in response to mechanical demands has long been recognized but the cellular mechanisms involved remained poorly understood. Bone not only develops as a structure designed specifically for mechanical tasks, but it can adapt during life toward more efficient mechanical performance. Mechanical adaptation of bone is a cellular process and needs a biological system that senses the mechanical loading. The loading information must then be communicated to the effector cells that form new bone or destroy old bone. The in vivo operating cell stress derived from bone loading is likely the flow of interstitial fluid along the surface of osteocytes and lining cells. The response of bone cells in culture to fluid flow includes prostaglandin (PG) synthesis and expression of prostaglandin G/H synthase inducible cyclooxygenase (COX-2). Cultured bone cells also rapidly produce nitric oxide (NO) in response to fluid flow as a result of activation of endothelial nitric oxide synthase (ecNOS), which enzyme also mediates the adaptive response of bone tissue to mechanical loading. Earlier studies have shown that the disruption of the actin-cytoskeleton abolishes the response to stress, suggesting that the cytoskeleton is involved in cellular mechanotransduction. Microgravity, or better near weightlessness, is associated with the loss of bone in astronauts, and has catabolic effects on mineral metabolism in bone organ cultures. This might be explained as resulting from an exceptional form of disuse under near weightlessness conditions. However, under near weightlessness conditions the assembly of cytoskeletal elements may be altered since it has been shown that the direction of the gravity vector determines microtubular pattern formation in vivo. We found earlier that the transduction of mechanical signals in bone cells also involves the cytoskeleton and is related to PGEZ production. Therefore it is possible that the

  5. Paget's Disease of Bone

    MedlinePlus

    ... page please turn Javascript on. Paget's Disease of Bone What is Paget's Disease of Bone? Click for more information Enlarged and Misshapen Bones Paget's disease of bone causes affected bones to ...

  6. Ethnic Differences in Bone Health

    PubMed Central

    Zengin, Ayse; Prentice, Ann; Ward, Kate Anna

    2015-01-01

    There are differences in bone health between ethnic groups in both men and in women. Variations in body size and composition are likely to contribute to reported differences. Most studies report ethnic differences in areal bone mineral density (aBMD), which do not consistently parallel ethnic patterns in fracture rates. This suggests that other parameters beside aBMD should be considered when determining fracture risk between and within populations, including other aspects of bone strength: bone structure and microarchitecture, as well as muscle strength (mass, force generation, anatomy) and fat mass. We review what is known about differences in bone-densitometry-derived outcomes between ethnic groups and the extent to which they account for the differences in fracture risk. Studies are included that were published primarily between 1994 and 2014. A “one size fits all approach” should definitely not be used to understand better ethnic differences in fracture risk. PMID:25852642

  7. Improved viability of random pattern skin flaps with the use of bone marrow mesenchymal-derived stem cells and chicken embryo extract

    PubMed Central

    Chehelcheraghi, Farzaneh; Eimani, Hossein; Sadraie, Seyed Homayoon; Torkaman, Giti; Amini, Abdollah; Shemshadi, Hashem; Majd, Hamid Alavi

    2015-01-01

    Objective(s): Covering tissue defects using skin flaps is a basic surgical strategy for plastic and reconstructive surgery. The aim of this study was to evaluate the effects of chicken embryo extract (CEE) and bone marrow derived mesenchymal stem cells (BM-MSCs) on random skin flap survival (RSF) in rats. Using chicken embryo extract can be an ideal environment for the growth and proliferation of transplanted cells. Materials and Methods: Forty albino male Wistar rats were divided into 4 groups; each group consisted of 10 rats. BM-MSCs and CEE were transplanted into subcutaneous tissue in the area, where the flap would be examined. On the 7th postoperative day, the survival areas of the flaps were measured by using digital imaging with software assistance, and tissue was collected for evaluation. Results: Survival area was 19.54±2 in the CEE group and 17.90±2 in the CEE/BM-MSC group when compared to the rates of the total skin flaps, which were significantly higher than the control group (13.47±2) (P<0.05). The biomechanical assessment showed a slight difference, although there was no statistically significant difference between the experimental groups and the control group (P>0.05). Conclusion: The findings from this study demonstrated that in operative treatment with BM-MSCs and CEE transplantation could promote flap survival, but the biomechanical parameters were not contrasted with a saline injection. PMID:26557965

  8. Bone densitometry.

    PubMed

    Chun, Kwang J

    2011-05-01

    Conventional radiographic methods allow physicians to visualize bone structure. However, they do not offer information on the bone mineral density (BMD), which can facilitate early diagnosis and treatment of osteoporosis. Bone densitometry, by contrast, helps to detect bone mineral loss at an early stage because it provides accurate quantitative measurement of BMD. With an emphasis on quantification, shorter scanning time and precision, scientists have been developing BMD measurement devices that use absorption technique. They first developed single-energy absorptiometry (single-photon absorptiometry) by using I-125, which could measure BMD of peripheral bones. Single-photon absorptiometry was replaced by dual-energy absorptiometry (dual photon absorptiometry [DPA]) that used gadolinium-153. DPA had greater accuracy in measuring the BMD of central skeletal bones. Single-energy x-ray absorptiometry was also developed but it had limitations in measuring central skeletal BMD. In the mid-1980s, dual-energy x-ray absorptiometry (DXA) was introduced and widely accepted for the early detection, treatment, and follow-up study of osteoporosis. There are several reasons for the popularity. DXA can measure BMD of posteroanterior spine and hip in a much shorter time than DPA while being capable of measuring BMD of peripheral bones. Other advantages include very low radiation doses to the patients, high image resolution, precision, and stable calibration of the instruments. In recent years, DXA has also been applied to lateral spine for the density of trabecular bone, to the whole body for the measurement of total body bone density and for the body composition, and to the spine for the vertebral fracture assessment. Still, posteroanterior spine and hip scans remain the most common applications of DXA because data on the normal range of BMD of the skeletal sites for different age, sex, and ethnic groups are compiled and made available with the devices, which gives the physician

  9. Bone Health

    PubMed Central

    Manske, Sarah L.; Lorincz, Caeley R.; Zernicke, Ron F.

    2009-01-01

    Mechanical loading is a crucial factor for maintaining skeletal health. Physical activities, exercise, and sports provide a wealth and variety of mechanical loads to bones, through muscle forces, ground reaction forces, and other contact or impact forces. Weightbearing activities can be effective exercises to enhance bone health—particularly, those that involve jumping and impact loads (with greater strain magnitudes, rates, and frequencies). Physical activity appears to be acutely beneficial for enhancing bone health in the early pubertal period and in older age, such as in postmenopausal women. In preparing this article, PubMed, Web of Science, and relevant edited books (English language) were reviewed from 1961 to present. PMID:23015892

  10. Overexpression of bone morphogenetic protein-6 (BMP-6) in the epidermis of transgenic mice: inhibition or stimulation of proliferation depending on the pattern of transgene expression and formation of psoriatic lesions

    PubMed Central

    1996-01-01

    Bone morphogenetic protein-6 (BMP-6) belongs to the family of TGF-beta- related growth factors. In the developing epidermis, expression of BMP- 6 coincides with the onset of stratification. Expression persists perinatally but declines after day 6 postpartum, although it can still be detected in adult skin by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. We constitutively overexpressed BMP-6 in suprabasal layers of interfollicular epidermis in transgenic mice using a keratin 10 promoter. All mice expressing the transgene developed abnormalities in the skin, indicating an active transgene-derived factor. Depending on the pattern of transgene expression, the effects on proliferation and differentiation were completely opposite. Strong and uniform expression of the BMP-6 transgene resulted in severe repression of cell proliferation in embryonic and perinatal epidermis but had marginal effects on differentiation. Weaker and patchy expression of the transgene evoked strong hyperproliferation and parakeratosis in adult epidermis and severe perturbations of the usual pattern of differentiation. These perturbations included changes in the expression of keratins and integrins. Together with an inflammatory infiltrate both in the dermis and in the epidermis, these aspects present all typical histological and biochemical hallmarks of a human skin disease: psoriasis. PMID:8858176

  11. The contribution of vegetation cover and bare soil to pixel reflectance in an arid ecosystem

    USDA-ARS?s Scientific Manuscript database

    The heterogeneity of vegetation and soils in arid and semi-arid environments complicates the analysis of medium spatial resolution remotely sensed imagery. A single pixel may contain several different types of vegetation, as well as a sizeable proportion of bare soil. We have used linear mixture mod...

  12. The Bare Facts about the Listener's Responsibility in Understanding Semantic Meaning.

    ERIC Educational Resources Information Center

    Bohlken, Bob

    The bare fact is that the speaker's words are nothing until the listener gives them meaning. The denotation of a word is developed through association with other words. The connotation is the more difficult concept to establish for the critical/comprehensive listener studying word meaning. The common explanation is that "connotation refers to…

  13. Distribution of Rhizoctonia Bare Patch and Root Rot in Eastern Washington and Relation to Climatic Variables

    USDA-ARS?s Scientific Manuscript database

    Rhizoctonia is a fungus that attacks the roots of wheat and barley, causing a root rot and bare patch in the dryland wheat cropping area of the inland Pacific Northwest. Over the last 7 years, we have been investigating the distribution of this pathogen, using molecular methods based on extracting a...

  14. Group and Individual Evidentials: Sentence-Final "No" and Bare Verbs in Japanese.

    ERIC Educational Resources Information Center

    Cook, Haruko Minegishi

    The Japanese sentence-final particle "no" is analyzed as a marker of evidentiality, signaling that the speaker shares a commitment to the knowledge in question with a group of which he is part. In contrast, bare verb forms (BVs) (i.e., the absence of "no") indicate that the speaker, as an individual, is committed to the…

  15. Analyses of protein corona on bare and silica-coated gold nanorods against four mammalian cells.

    PubMed

    Das, Minakshi; Yi, Dong Kee; An, Seong Soo A

    2015-01-01

    The purpose of this study was to investigate the mechanisms responsible for the toxic effects of gold nanorods (AuNRs). Here, a comprehensive study was performed by examining the effects of bare (uncoated) AuNRs and AuNRs functionalized with silica (SiO2-AuNRs) against various mammalian cell lines, including cervical cancer cells, fibroblast cells, human umbilical vein endothelial cells, and neuroblastoma cells. The interactions between AuNRs and mammalian cells were investigated with cell viability and mortality assays. Dihydrorhodamine-123 assay was carried out for evaluating reactive oxygen species (ROS) generation, along with mass spectroscopy analysis for determining the composition of the protein corona. Our results suggest that even the lowest concentrations of AuNRs (0.7 μg/mL) induced ROS production leading to cell mortality. On the other hand, cellular viability and ROS production were maintained even at a higher concentration of SiO2-coated AuNRs (12 μg/mL). The increased production of ROS by AuNRs seemed to cause the toxicity observed in all four mammalian cell types. The protein corona on the bare AuNRs did not appear to reduce ROS generation; however, different compositions of the protein corona on bare and SiO2-coated AuNRs may affect cellular behavior differently. Therefore, it was determined that SiO2-coated AuNRs would be more advantageous than bare AuNRs for cellular applications.

  16. Bare Forms and Lexical Insertions in Code-Switching: A Processing-Based Account

    ERIC Educational Resources Information Center

    Owens, Jonathan

    2005-01-01

    Bare forms (or [slashed O] forms), uninflected lexical L2 insertions in contexts where the matrix language expects morphological marking, have been recognized as an anomaly in different approaches to code-switching. Myers-Scotton (1997, 2002) has explained their existence in terms of structural incongruity between the matrix and embedded…

  17. Bare Pedagogy and the Scourge of Neoliberalism: Rethinking Higher Education as a Democratic Public Sphere

    ERIC Educational Resources Information Center

    Giroux, Henry A.

    2010-01-01

    A new form of bare pedagogy is emerging in higher education focused on market-driven competitiveness and even militaristic goal-setting, while critical pedagogy, with its emphasis on the hard work of critical analysis, moral judgments, and social responsibility (critical pedagogy that goes to the very heart of what it means to address real…

  18. Soil carbon dioxide fluxes with time and depth in a bare field

    USDA-ARS?s Scientific Manuscript database

    Soil carbon dioxide (CO2) efflux is an important component of the terrestrial carbon cycle. The amount of CO2 emitted from soil to the atmosphere has significant effects on the soil-atmosphere system. The objectives of this study are 1) to determine bare soil CO2 fluxes continuously with time and de...

  19. Patients' perceptions of doctors' clothing: should we really be 'bare below the elbow'?

    PubMed

    Bond, L; Clamp, P J; Gray, K; Van Dam, V

    2010-09-01

    In September 2007, the Department of Health published Uniforms and Workwear: an Evidence Base for Guiding Local Policy. Following this, most National Health Service trusts imposed a 'bare below the elbow' dress code policy, with clinical staff asked to remove ties, wristwatches and hand jewellery and to wear short-sleeved tops. There is currently no evidence linking dress code to the transmission of hospital-acquired infection. We designed the current survey to assess patients' perceptions of doctors' appearance, with specific reference to the 'bare below the elbow' policy. A questionnaire showing photographs of a doctor in three different types of attire ('scrubs', formal attire and 'bare below the elbow') were used to gather responses from 80 in-patients and 80 out-patients in the ENT department. Patients were asked which outfit they felt was the most hygienic, the most professional and the easiest identification of the person as a doctor. They were also asked to indicate their overall preference. Formal attire was considered most professional and the easiest identification that the person was a doctor. Scrubs were considered most hygienic. Respondents' overall preference was divided between scrubs and formal clothes. 'Bare below the elbow' attire received the lowest votes in all categories. This finding raises significant questions about the Department of Health policy in question. The authors suggest that an alternative policy should be considered, with scrubs worn for in-patient situations and formal attire during out-patient encounters.

  20. Introducing the Notion of Bare and Effective Mass via Newton's Second Law of Motion

    ERIC Educational Resources Information Center

    Pinto, Marcus Benghi

    2007-01-01

    The concepts of bare and effective mass are widely used within modern physics. Their meaning is discussed in advanced undergraduate and graduate courses such as solid state physics, nuclear physics and quantum field theory. Here I discuss how these concepts may be introduced together with the discussion of Newton's second law of motion. The…

  1. 3D laser measurements of bare and shod feet during walking.

    PubMed

    Novak, Boštjan; Možina, Janez; Jezeršek, Matija

    2014-01-01

    This article presents a new system for 3D foot-shape measurements during walking. It is based on the laser-triangulation, multiple-line-illumination and color-modulation techniques. It consists of a walking stage and four measuring modules that simultaneously acquire the foot shape from the top, bottom and side views. The measuring speed is 30 fps. Custom-developed software makes it possible to analyze the foot's dimensions at an arbitrary cross-section by means of the width, height, girth and section orientation. Six subjects were measured during bare and shod walking, and the bare foot and the outside dimensions of the footwear during the entire stance phase are presented. The relative measurement repeatability of a single subject is 0.5% for bare foot and 1% for shod foot. This means that it is possible to study the differences between various influences on the foot-shape dynamics, such as a bare/shod foot, different loading conditions and the shoe's stiffness condition.

  2. Unexpectedly high activity of bare alumina for non-oxidative isobutane dehydrogenation.

    PubMed

    Rodemerck, Uwe; Kondratenko, Evgenii V; Otroshchenko, Tatyana; Linke, David

    2016-10-06

    Bare alumina shows surprisingly high activity in non-oxidative dehydrogenation of isobutane to isobutylene. The activity is related to surface coordinatively unsaturated Al sites (Alcus), which are created upon removal of OH groups during alumina treatment at high temperatures. Alcus and neighbouring lattice oxygen represent the active site for isobutane dehydrogenation.

  3. DETAIL VIEW, SOUTH PORTICO. THE BARE GROUND BENEATH THE PORTICO’S ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW, SOUTH PORTICO. THE BARE GROUND BENEATH THE PORTICO’S CENTER BAY DISCLOSES THE LOCATION OF A REMOVED STAIR. THE ORIGINAL FRAME STAIRCASES UP TO THE PORTICO EXTENDED FROM THE EAST AND WEST SIDES - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

  4. Bare Forms and Lexical Insertions in Code-Switching: A Processing-Based Account

    ERIC Educational Resources Information Center

    Owens, Jonathan

    2005-01-01

    Bare forms (or [slashed O] forms), uninflected lexical L2 insertions in contexts where the matrix language expects morphological marking, have been recognized as an anomaly in different approaches to code-switching. Myers-Scotton (1997, 2002) has explained their existence in terms of structural incongruity between the matrix and embedded…

  5. Bare Pedagogy and the Scourge of Neoliberalism: Rethinking Higher Education as a Democratic Public Sphere

    ERIC Educational Resources Information Center

    Giroux, Henry A.

    2010-01-01

    A new form of bare pedagogy is emerging in higher education focused on market-driven competitiveness and even militaristic goal-setting, while critical pedagogy, with its emphasis on the hard work of critical analysis, moral judgments, and social responsibility (critical pedagogy that goes to the very heart of what it means to address real…

  6. Predicting first-year bare-root seedling establishment with soil and community dominance factors

    Treesearch

    Robin E. Durham; Benjamin A. Zamora; Michael R. Sackschewsky; Jason C. Ritter

    2001-01-01

    The usefulness of measuring community dominance factors and the soil parameters of geometric mean particle size and percent fines as predictors of first-year bare-root establishment of Wyoming big sagebrush seedlings was investigated. The study was conducted on six sandy soils in south-central Washington. Soil parameters that could affect the distribution of Sandberg’s...

  7. Introducing the Notion of Bare and Effective Mass via Newton's Second Law of Motion

    ERIC Educational Resources Information Center

    Pinto, Marcus Benghi

    2007-01-01

    The concepts of bare and effective mass are widely used within modern physics. Their meaning is discussed in advanced undergraduate and graduate courses such as solid state physics, nuclear physics and quantum field theory. Here I discuss how these concepts may be introduced together with the discussion of Newton's second law of motion. The…

  8. In vivo comparative study of tissue reaction to bare and antimicrobial polymer coated transcutaneous implants.

    PubMed

    Calliess, Tilman; Bartsch, Ivonne; Haupt, Maike; Reebmann, Mattias; Schwarze, Michael; Stiesch, Meike; Pfaffenroth, Cornelia; Sluszniak, Magda; Dempwolf, Wibke; Menzel, Henning; Witte, Frank; Willbold, Elmar

    2016-04-01

    We coated transcutaneous implants made of titanium alloy Ti6Al4V with copolymer dimethyl (2-methacryloyloxy-ethyl) phosphonate and 4-vinylpyridine and investigated the tissue reaction with respect to its biocompatible and antimicrobial properties in vivo. We distinguished between clinically observable superficial inflammations and histologically detectable deep infections. The vinylpyridine moieties were transferred into cationic pyridinium groups by reaction with hexyl bromide. Thus polymers with both antimicrobial capacity and good biocompatibility were obtained. In a short-term study, we implanted specially designed bare or coated implants in hairless but immunocompetent mice and analyzed the tissue reaction histologically. No difference was found between bare and coated implants in the initial healing phase of up to 14 days; however, after 21 days the scar tissue formation was higher in the bare implant group. The degree of epithelial downgrowth was comparable in both groups at any time point. In a long-term study of up to 168 days, we analyzed resistance to infection. In the bare implant group, 7 of the 12 implantation sites became infected deep whereas in the coated implant group only two deep infections were observed. The other implantation sites showed only superficial signs of inflammation. These results generally accord with previous in-vitro studies.

  9. EAARL Coastal Topography—Northern Assateague Island National Seashore, Maryland and Virginia, 2003: Bare earth

    USGS Publications Warehouse

    Kranenburg, Christine; Fredericks, Alexandra M.; Nagle, David B.

    2017-01-01

    These datasets, prepared by the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center in collaboration with the National Park Service, provide lidar-derived bare-earth topography for Northern Assateague Island National Seashore, Maryland and Virginia. Elevation measurements were acquired by the Experimental Advanced Airborne Research Lidar (EAARL) during February 2003.

  10. Health in post-Black Death London (1350-1538): age patterns of periosteal new bone formation in a post-epidemic population.

    PubMed

    DeWitte, Sharon N

    2014-10-01

    Previous research has shown that the Black Death targeted older adults and individuals who had been previously exposed to physiological stressors. This project investigates whether this selectivity of the Black Death, combined with post-epidemic rising standards of living, led to significant improvements in patterns of skeletal stress markers, and by inference in health, among survivors and their descendants. Patterns of periosteal lesions (which have been previously shown, using hazard analysis, to be associated with elevated risks of mortality in medieval London) are compared between samples from pre-Black Death (c. 1,000-1,300, n = 464) and post-Black Death (c. 1,350-1,538, n = 133) London cemeteries. To avoid the assumptions that stress markers alone provide a direct measure of health and that a change in frequencies of the stress marker by itself indicates changes in health, this study assesses age-patterns of the stress marker to obtain a more nuanced understanding of the population-level effects of an epidemic disease. Age-at-death in these samples is estimated using transition analysis, which provides point estimates of age even for the oldest adults in these samples and thus allows for an examination of physiological stress across the lifespan. The frequency of lesions is significantly higher in the post-Black Death sample, which, at face value, might indicate a general decline in health. However, a significant positive association between age and periosteal lesions, as well as a significantly higher number of older adults in the post-Black Death sample more likely suggests improvements in health following the epidemic. © 2014 Wiley Periodicals, Inc.

  11. Employing UAVs to Acquire Detailed Vegetation and Bare Ground Data for Assessing Rangeland Health

    NASA Astrophysics Data System (ADS)

    Rango, A.; Laliberte, A.; Herrick, J. E.; Winters, C.

    2007-12-01

    Because of its value as a historical record (extending back to the mid 1930s), aerial photography is an important tool used in many rangeland studies. However, these historical photos are not very useful for detailed analysis of rangeland health because of inadequate spatial resolution and scheduling limitations. These issues are now being resolved by using Unmanned Aerial Vehicles (UAVs) over rangeland study areas. Spatial resolution improvements have been rapid in the last 10 years from the QuickBird satellite through improved aerial photography to the new UAV coverage and have utilized improved sensors and the more simplistic approach of low altitude flights. Our rangeland health experiments have shown that the low altitude UAV digital photography is preferred by rangeland scientists because it allows, for the first time, their identification of vegetation and land surface patterns and patches, gap sizes, bare soil percentages, and vegetation type. This hyperspatial imagery (imagery with a resolution finer than the object of interest) is obtained at about 5cm resolution by flying at an altitude of 150m above the surface of the Jornada Experimental Range in southern New Mexico. Additionally, the UAV provides improved temporal flexibility, such as flights immediately following fires, floods, and other catastrophic disturbances, because the flight capability is located near the study area and the vehicles are under the direct control of the users, eliminating the additional steps associated with budgets and contracts. There are significant challenges to improve the data to make them useful for operational agencies, namely, image distortion with inexpensive, consumer grade digital cameras, difficulty in detecting sufficient ground control points in small scenes (152m by 114m), accuracy of exterior UAV information on X,Y, Z, roll, pitch, and heading, the sheer number of images collected, and developing reliable relationships with ground-based data across a broad

  12. GM-CSF Priming Drives Bone Marrow-Derived Macrophages to a Pro-Inflammatory Pattern and Downmodulates PGE2 in Response to TLR2 Ligands

    PubMed Central

    Sorgi, Carlos Arterio; Rose, Stephanie; Court, Nathalie; Carlos, Daniela; Paula-Silva, Francisco Wanderley Garcia; Assis, Patricia Aparecida; Frantz, Fabiani Gai; Ryffel, Bernhard; Quesniaux, Valerie; Faccioli, Lúcia Helena

    2012-01-01

    In response to pathogen recognition by Toll-like receptors (TLRs) on their cell surface, macrophages release lipid mediators and cytokines that are widely distributed throughout the body and play essential roles in host responses. Granulocyte macrophage colony-stimulating factor (GM-CSF) is important for the immune response during infections to improve the clearance of microorganisms. In this study, we examined the release of mediators in response to TLR2 ligands by bone marrow-derived macrophages (BMDMs) primed with GM-CSF. We demonstrated that when stimulated with TLR2 ligands, non-primed BMDMs preferentially produced PGE2 in greater amounts than LTB4. However, GM-CSF priming shifted the release of lipid mediators by BMDMs, resulting in a significant decrease of PGE2 production in response to the same stimuli. The decrease of PGE2 production from primed BMDMs was accompanied by a decrease in PGE-synthase mRNA expression and an increase in TNF-α and nitric oxide (NO) production. Moreover, some GM-CSF effects were potentiated by the addition of IFN-γ. Using a variety of TLR2 ligands, we established that PGE2 release by GM-CSF-primed BMDMs was dependent on TLR2 co-receptors (TLR1, TLR6), CD14, MyD88 and the nuclear translocation of NFκB but was not dependent on peroxisome proliferator-activated receptor-γ (PPAR-γ) activation. Indeed, GM-CSF priming enhanced TLR2, TLR4 and MyD88 mRNA expression and phospho-IκBα formation. These findings demonstrate that GM-CSF drives BMDMs to present a profile relevant to the host during infections. PMID:22808181

  13. Bone Scan

    MedlinePlus

    ... injected, then shortly after the injection, and again two to four hours later. To better see some bones in your body, your doctor might order additional imaging called single-photon emission computerized tomography (SPECT). This imaging can help ...

  14. Interpreting Bones.

    ERIC Educational Resources Information Center

    Weymouth, Patricia P.

    1986-01-01

    Describes an activity which introduces students to the nature and challenges of paleoanthropology. In the exercise, students identify diagrammed bones and make interpretations about the creature. Presents questions and tasks employed in the lesson. (ML)

  15. Microgravity and Bone Cell Mechanosensitivity

    NASA Astrophysics Data System (ADS)

    Klein-Nulend, J.; Bacabac, R.; Veldhuijzen, J.; van Loon, J.

    The capacity of bone tissue to alter its mass and structure in response to mechanical demands has long been recognized but the cellular mechanisms involved remained poorly understood. Bone not only develops as a structure designed specifically for mechanical tasks, but it can adapt during life toward more efficient mechanical performance. Mechanical adaptation of bone is a cellular process and needs a biological system that senses the mechanical loading. The loading information must then be communicated to the effector cells that form new bone or destroy old bone.The in vivo operating cell stress derived from bone loading is likely flow of interstitial fluid along the surface of osteocytes and lining cells. The response of bone cells in culture to fluid flow includes prostaglandin (PG) synthesis and expression of prostaglandin G/H synthase inducible cyclooxygenase (COX-2). Cultured bone cells also rapidly produce nitric oxide (NO) in response to fluid flow as a result of activation of endothelial nitric oxide synthase (ecNOS), which enzyme also mediates the adaptive response of bone tissue to mechanical loading. Disruption of the actin-cytoskeleton abolishes the response to stress, suggesting that the cytoskeleton is involved in cellular mechanotransduction.Microgravity, or better near weightlessness, has catabolic effects on the skeleton of astronauts, and on mineral metabolism in bone organ cultures. This might be explained as resulting from an exceptional form of disuse under near weightlessness conditions. However, under near weightlessness conditions the assembly of cytoskeletal elements may be altered since it has been shown that the direction of the gravity vector determines microtubular pattern formation in vivo. We found that the transduction of mechanical signals in bone cells also involves the cytoskeleton and is related to PGE2 production. Therefore it is possible that the mechanosensitivity of bone cells is altered under near weightlessness conditions

  16. Bone and bone marrow: the same organ.

    PubMed

    Del Fattore, Andrea; Capannolo, Marta; Rucci, Nadia

    2010-11-01

    Interplays between bone and bone marrow are not limited to merely anatomic and histological connections, but include a tight functional correlation. Bone marrow resides within the medullary cavity of the bones and the process of hematopoiesis is regulated, at least in part, by bone cells. Moreover, osteoclasts and osteoblasts derive from precursors of hematopoietic and mesenchymal origin, respectively, both residing within the bone marrow. Alterations in one of these components typically cause impairment in the other, so diseases of the bone marrow compartment often affect the bone and vice versa. All these findings could make us to speculate that bone and bone marrow are not two separate districts, but can be considered as the two elements of the same unique functional unit, the bone-bone marrow organ. Here we will describe histological and functional interplays between bone and bone marrow, and will illustrate some diseases in which this tight correlation is evident.

  17. Bone healing around nanocrystalline hydroxyapatite, deproteinized bovine bone mineral, biphasic calcium phosphate, and autogenous bone in mandibular bone defects.

    PubMed

    Broggini, Nina; Bosshardt, Dieter D; Jensen, Simon S; Bornstein, Michael M; Wang, Chun-Cheng; Buser, Daniel

    2015-10-01

    The individual healing profile of a given bone substitute with respect to osteogenic potential and substitution rate must be considered when selecting adjunctive grafting materials for bone regeneration procedures. In this study, standardized mandibular defects in minipigs were filled with nanocrystalline hydroxyapatite (HA-SiO), deproteinized bovine bone mineral (DBBM), biphasic calcium phosphate (BCP) with a 60/40% HA/β-TCP (BCP 60/40) ratio, or particulate autogenous bone (A) for histological and histomorphometric analysis. At 2 weeks, percent filler amongst the test groups (DBBM (35.65%), HA-SiO (34.47%), followed by BCP 60/40 (23.64%)) was significantly higher than the more rapidly substituted autogenous bone (17.1%). Autogenous bone yielded significantly more new bone (21.81%) over all test groups (4.91%-7.74%) and significantly more osteoid (5.53%) than BCP 60/40 (3%) and DBBM (2.25%). At 8 weeks, percent filler amongst the test groups (DBBM (31.6%), HA-SiO (31.23%), followed by BCP 60/40 (23.65%)) demonstrated a similar pattern and was again significantly higher as compared to autogenous bone (9.29%). Autogenous bone again exhibited statistically significantly greater new bone (55.13%) over HA-SiO (40.62%), BCP 60/40 (40.21%), and DBBM (36.35%). These results suggest that the osteogenic potential of HA-SiO and BCP is inferior when compared to autogenous bone. However, in instances where a low substitution rate is desired to maintain the volume stability of augmented sites, particularly in the esthetic zone, HA-SiO and DBBM may be favored.

  18. [Bone disease in Gaucher's disease].

    PubMed

    Roca Espiau, Mercedes

    2011-09-01

    The exposition aims, is to review the pathophysiological mechanisms of bone marrow involvement and the patterns of marrow infiltration by Gaucher cells. We have reviewed the different methods of assessment of bone marrow infiltration and its temporal development. Qualitative methods include simple radiography, magnetic resonance imaging (MRI), computed tomography (CT) and radioisotope. The simple radiography is the basic element, but its sensitivity is limited and only allows for assessing changes and trabecular bone remodeling MRI allows us to appreciate the bone marrow infiltration, detection of complications and response to therapy. Radioisotopes can contribute to the differential diagnosis of osteomyelitis and bone crises. Among the quantitative methods are the QCSI (quantitative chemical shift imaging) and the dual-energy X-ray absorptiometry (DEXA), as well as new quantitative techniques of CT, MRI and ultrasound densitometry. The QCSI performed an assessment of fat content of bone marrow in the spine. DEXA quantifies bone density by measuring the attenuation coefficient. The semiquantitative methods have various "scores" to establish criteria for generalized bone disease endpoints of disease progression and response to therapy.

  19. Bare Bones: An Introduction to Physical Anthropology. Alternative Techniques for Teaching Physical Anthropology to Learning Disabled Students in the University.

    ERIC Educational Resources Information Center

    Sands, Catherine J. MacMillan

    The booklet describes approaches to teaching learning disabled students introductory physical anthropology, as related by a professor involved in the Higher Education for Learning Disabled Students (HELDS) program. The author suggests ways to identify LD students through observation of short attention span, restlessness, and marked discrepancies…

  20. Bone Densitometry (Bone Density Scan)

    MedlinePlus

    ... and display the bone density measurements on a computer monitor. top of page How is the procedure performed? ... passed over the area, generating images on a computer monitor. You must hold very still and may be ...

  1. 30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 75.1003 Section 75.1003... Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and...

  2. 30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 77.1802 Section 77.1802... Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare...

  3. 30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 75.1003 Section 75.1003... Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and...

  4. 30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 77.1802 Section 77.1802... Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare...

  5. 30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 75.1003 Section 75.1003... Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and...

  6. 30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 75.1003 Section 75.1003... Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and...

  7. 30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 77.1802 Section 77.1802... Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare...

  8. 30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley wires and trolley feeder wires. 77.1802 Section 77.1802... Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare...

  9. Performance of Slash Pine Bare-Root Seedlings and Containerized Rooted Cuttings Planted on Five Dates in Louisiana

    Treesearch

    Alper Akgul; Michael G. Messina; Alan Wilson; Joe Weber

    2004-01-01

    Landowners are interested in extending the normal planting season, as well as the comparative field performance, of nursery bare-root seedlings and containerized rooted cuttings. The effect of seasonal planting dates on field performance of two stock types of slash pine (Pinus elliottii Engelm.) was examined. Slash pine bare-root seedlings (BRS) and...

  10. Bone marrow transplant

    MedlinePlus

    Transplant - bone marrow; Stem cell transplant; Hematopoietic stem cell transplant; Reduced intensity nonmyeloablative transplant; Mini transplant; Allogenic bone marrow transplant; Autologous bone marrow transplant; ...

  11. Using Micro-CT Derived Bone Microarchitecture to Analyze Bone Stiffness – A Case Study on Osteoporosis Rat Bone

    PubMed Central

    Wu, Yuchin; Adeeb, Samer; Doschak, Michael R.

    2015-01-01

    Micro-computed tomography (Micro-CT) images can be used to quantitatively represent bone geometry through a range of computed attenuation-based parameters. Nonetheless, those parameters remain indirect indices of bone microarchitectural strength and require further computational tools to interpret bone structural stiffness and potential for mechanical failure. Finite element analysis (FEA) can be applied to measure trabecular bone stiffness and potentially predict the location of structural failure in preclinical animal models of osteoporosis, although that procedure from image segmentation of Micro-CT derived bone geometry to FEA is often challenging and computationally expensive, resulting in failure of the model to build. Notably, the selection of resolution and threshold for bone segmentation are key steps that greatly affect computational complexity and validity. In the following study, we evaluated an approach whereby Micro-CT derived grayscale attenuation and segmentation data guided the selection of trabecular bone for analysis by FEA. We further correlated those FEA results to both two- and three-dimensional bone microarchitecture from sham and ovariectomized (OVX) rats (n = 10/group). A virtual cylinder of vertebral trabecular bone 40% in length from the caudal side was selected for FEA, because Micro-CT based image analysis indicated the largest differences in microarchitecture between the two groups resided there. Bone stiffness was calculated using FEA and statistically correlated with the three-dimensional values of bone volume/tissue volume, bone mineral density, fractal dimension, trabecular separation, and trabecular bone pattern factor. Our method simplified the process for the assessment of trabecular bone stiffness by FEA from Micro-CT images and highlighted the importance of bone microarchitecture in conferring significantly increased bone quality capable of resisting failure due to increased mechanical loading. PMID:26042089

  12. Modelling emergent patterns of dynamic desert ecosystems

    USDA-ARS?s Scientific Manuscript database

    In many desert ecosystems vegetation is both patchy and dynamic: vegetated areas are interspersed with patches of bare ground, and both the positioning and the species composition of the vegetated areas exhibit change through time. These characteristics lead to the emergence of multi-scale patterns ...

  13. Implications of climate change for evaporation from bare soils in a Mediterranean environment.

    PubMed

    Aydin, Mehmet; Yano, Tomohisa; Evrendilek, Fatih; Uygur, Veli

    2008-05-01

    The purpose of this study was to predict quantitative changes in evaporation from bare soils in the Mediterranean climate region of Turkey in response to the projections of a regional climate model developed in Japan (hereafter RCM). Daily RCM data for the estimation of reference evapotranspiration (ETr) and soil evaporation were obtained for the periods of 1994--2003 and 2070--2079. Potential evaporation (Ep) from bare soils was calculated using the Penman-Monteith equation with a surface resistance of zero. Simulation of actual soil evaporation (Ea) was carried out using Aydin model (Aydin et al., Ecological Modelling 182:91-105, 2005) combined with Aydin and Uygur (2006, A model for estimating soil water potential of bare fields. In Proceedings of the 18th International Soil Meeting (ISM) on Soils Sustaining Life on Earth, Managing Soil and Technology, Sanliurfa, 477-480pp.) model of predicting soil water potential at the top surface layer of a bare soil, after performances of Aydin model (R2 = 94.0%) and Aydin and Uygur model (R2 = 97.6) were tested. The latter model is based on the relations among potential soil evaporation, hydraulic diffusivity, and soil wetness, with some simplified assumptions. Input parameters of the model are simple and easily obtainable such as climatic parameters used to compute the potential soil evaporation, average diffusivity for the drying soil, and volumetric water content at field capacity. The combination of Aydin and Aydin and Uygur models appeared to be useful in estimating water potential of soils and Ea from bare soils, with only a few parameters. Unlike ETr and Ep projected to increase by 92 and 69 mm (equivalent to 8.0 and 7.3% increases) due to the elevated evaporative demand of the atmosphere, respectively, Ea from bare soils is projected to reduce by 50 mm (equivalent to a 16.5% decrease) in response to a decrease in rainfall by 46% in the Mediterranean region of Turkey by the 2070s predicted by RCM, and consequently

  14. Runoff and Sediment Delivery from Bare and Graveled Forest Road Approaches to Stream Crossings

    NASA Astrophysics Data System (ADS)

    Brown, K. R.; McGuire, K. J.; Aust, W. M.

    2012-12-01

    Forested watersheds are typically associated with high quality water yield, yet forest roads and trails can adversely impact water quality draining forested watersheds. Increased stream sedimentation from forest road stream crossings often represents the most significant water quality threat associated with forestry operations. Quantification of sediment delivery rates is essential for the prescription of Best Management Practices (BMPs) that adequately address forest road stormwater runoff. Two different field experiments were implemented in the Virginia Piedmont to achieve the objectives of quantifying sediment delivery from forest roads where the road meets the stream (the road approach) and evaluating the sediment reduction efficacy of partially graveling road approaches. A forest operational experiment that included sediment traps and differential leveling was used to measure sediment delivery from five bare and four fully graveled road approaches for one year (August 2011 through July 2012). Rainfall simulation experiments were performed on six additional approaches to measure stormwater runoff volume, infiltration, and sediment delivery for 10 to 50-minute rain events with rainfall recurrence intervals of < 1 to 5-year return periods. Rainfall simulations were performed on newly-reopened bare approaches, with subsequent simulations on partially graveled approaches. The sediment trap study provides annual sediment delivery rates for bare and fully graveled road approaches. The rainfall simulation experiments characterize sediment delivery during storm events and provide an evaluation of different levels of Best Management Practice (BMP) implementation (i.e. ¼ to full gravel coverage) to minimize sediment inputs from road approaches. Sediment delivery from both experiments was related to rainfall amount, timing, and intensity, as well as road approach characteristics such as length, slope, and percentage of bare soil through stepwise multiple regression

  15. Paclitaxel-eluting stents versus bare-metal stents in acute myocardial infarction.

    PubMed

    Stone, Gregg W; Lansky, Alexandra J; Pocock, Stuart J; Gersh, Bernard J; Dangas, George; Wong, S Chiu; Witzenbichler, Bernhard; Guagliumi, Giulio; Peruga, Jan Z; Brodie, Bruce R; Dudek, Dariusz; Möckel, Martin; Ochala, Andrzej; Kellock, Alison; Parise, Helen; Mehran, Roxana

    2009-05-07

    There is no consensus regarding the safety and efficacy of drug-eluting stents, as compared with bare-metal stents, in patients with ST-segment elevation myocardial infarction who are undergoing primary percutaneous coronary intervention (PCI). We randomly assigned, in a 3:1 ratio, 3006 patients presenting with ST-segment elevation myocardial infarction to receive paclitaxel-eluting stents (2257 patients) or otherwise identical bare-metal stents (749 patients). The two primary end points of the study were the 12-month rates of target-lesion revascularization for ischemia (analysis powered for superiority) and a composite safety outcome measure of death, reinfarction, stroke, or stent thrombosis (powered for noninferiority with a 3.0% margin). The major secondary end point was angiographic evidence of restenosis at 13 months. Patients who received paclitaxel-eluting stents, as compared with those who received bare-metal stents, had significantly lower 12-month rates of ischemia-driven target-lesion revascularization (4.5% vs. 7.5%; hazard ratio, 0.59; 95% confidence interval [CI], 0.43 to 0.83; P=0.002) and target-vessel revascularization (5.8% vs. 8.7%; hazard ratio, 0.65; 95% CI, 0.48 to 0.89; P=0.006), with noninferior rates of the composite safety end point (8.1% vs. 8.0%; hazard ratio, 1.02; 95% CI, 0.76 to 1.36; absolute difference, 0.1 percentage point; 95% CI, -2.1 to 2.4; P=0.01 for noninferiority; P=0.92 for superiority). Patients treated with paclitaxel-eluting stents and those treated with bare-metal stents had similar 12-month rates of death (3.5% and 3.5%, respectively; P=0.98) and stent thrombosis (3.2% and 3.4%, respectively; P=0.77). The 13-month rate of binary restenosis was significantly lower with paclitaxel-eluting stents than with bare-metal stents (10.0% vs. 22.9%; hazard ratio, 0.44; 95% CI, 0.33 to 0.57; P<0.001). In patients with ST-segment elevation myocardial infarction who were undergoing primary PCI, implantation of paclitaxel

  16. A computer program to perform dynamic thermal analysis for bare overhead conductors during short-time overload conditions

    SciTech Connect

    Shrestha, P.; Pham, K.

    1995-12-31

    Under emergency conditions, a bare overhead conductor can carry an increased amount of current that is well in excess of its normal rating. When there is this increase in current flow on a bare overhead conductor, the temperature does not rise instantaneously. but increases along a curve determined by the current, the conductor properties and the ambient conditions. The conductor temperature at the end of a short-time overload period must be restricted to its maximum design value. This paper presents a simplified approach in analyzing the dynamic performance for bare overhead conductors during short-time overload condition. A computer program was developed to calculate the short-time ratings for bare overhead conductors. The following parameters: current induced heating. solar load, convective/conductive cooling, radiative cooling, altitude, wind velocity and ampacity of the bare conductor were considered. Several sample graphical output lots are included with the paper.

  17. Management of severe femoral bone loss in revision total hip arthroplasty.

    PubMed

    Sheth, Neil P; Melnic, Christopher M; Rozell, Joshua C; Paprosky, Wayne G

    2015-07-01

    Femoral bone loss is a complex problem in revision total hip arthroplasty. The Paprosky classification is used when determining the degree and location of bone loss. Meticulous operative planning is essential where severe bone loss is a concern. One must correctly identify the bone loss pattern, safely remove the existing components, and proceed with the proper reconstruction technique based on the pattern of bone loss. This article discusses the etiology and classification of bone loss, clinical and radiographic evaluation, components of effective preoperative planning, and clinical results of various treatment options with a focus on more severe bone loss patterns. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Chondroblastoma of the Temporal Bone

    PubMed Central

    Selesnick, Samuel H.; Levine, Jennifer M.

    1999-01-01

    The objective of this study is to describe the presentation and clinical course of two patients with temporal bone chondroblastoma, and to review the literature on temporal bone chondroblastoma to identify characteristic clinical and radiological presentations, and optimal treatment regimens. MEDLINE literature searches covering the period from 1966 to January 1998, in all languages, were performed as well as a review of the bibliographies of the identified studies. Strict inclusion criteria were upheld, In total 18 studies had patients whose data could be analyzed. From the 18 studies, 34 patients were identified, but only 21 cases met the inclusion criteria. Demographic, clinical presentation, radiological, operative and treatment parameters were analyzed in this cohort of patients. Ninety-five percent of patients were found to have invasion of the middle cranial fossa and 76% were found to have erosion into the superior aspect of the external auditory canal by temporal bone chondroblastoma. The characteristic growth pattern of temporal bone chondroblastoma may result from embryonal or cartilagenous rests entrapped in the tympanosquamous suture line in the middle fossa floor. Temporal bone chondroblastoma represents a pathology that does not arise from, or have a growth pattern resembling other pathologies in the temporal bone. ImagesFigure 1Figure 2 PMID:17171120

  19. Patterns and Timing of Failure for Diffuse Large B-Cell Lymphoma After Initial Therapy in a Cohort Who Underwent Autologous Bone Marrow Transplantation for Relapse.

    PubMed

    Dhakal, Sughosh; Bates, James E; Casulo, Carla; Friedberg, Jonathan W; Becker, Michael W; Liesveld, Jane L; Constine, Louis S

    2016-10-01

    To evaluate the location and timing of initial recurrence in patients with diffuse large B-cell lymphoma (DLBCL) who subsequently underwent high-dose chemotherapy with autologous stem cell transplant (HDC/ASCT), to direct approaches for disease surveillance, elucidate the patterns of failure of contemporary treatment strategies, and guide adjuvant treatment decisions. We analyzed consecutive patients with DLBCL who underwent HDC/ASCT between May 1992 and March 2014 at our institution. Of the 187 evaluable patients, 8 had incomplete data, and 79 underwent HDC/ASCT as a component of initial treatment for de novo or refractory DLBCL and were excluded from further analysis. The median age was 50.8 years; the median time to relapse was 1.3 years. Patients were segregated according to the initial stage at diagnosis, with early stage (ES) defined as stage I/II and advanced stage (AS) defined as stage III/IV. In total, 40.4% of the ES and 75.5% of the AS patients relapsed in sites of initial disease; 68.4% of those with ES disease and 75.0% of those with AS disease relapsed in sites of initial disease only. Extranodal relapses were common (44.7% in ES and 35.9% in AS) and occurred in a variety of organs, although gastrointestinal tract/liver (n=12) was most frequent. Most patients with DLBCL who relapse and subsequently undergo HDC/ASCT initially recur in the previously involved disease site(s). Time to recurrence is brief, suggesting that frequency of screening is most justifiably greatest in the early posttherapy years. © 2016 Elsevier Inc. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Dual frequency microwave radiometer measurements of soil moisture for bare and vegetated rough surfaces

    NASA Technical Reports Server (NTRS)

    Lee, S. L.

    1974-01-01

    Controlled ground-based passive microwave radiometric measurements on soil moisture were conducted to determine the effects of terrain surface roughness and vegetation on microwave emission. Theoretical predictions were compared with the experimental results and with some recent airborne radiometric measurements. The relationship of soil moisture to the permittivity for the soil was obtained in the laboratory. A dual frequency radiometer, 1.41356 GHz and 10.69 GHz, took measurements at angles between 0 and 50 degrees from an altitude of about fifty feet. Distinct surface roughnesses were studied. With the roughness undisturbed, oats were later planted and vegetated and bare field measurements were compared. The 1.4 GHz radiometer was less affected than the 10.6 GHz radiometer, which under vegetated conditions was incapable of detecting soil moisture. The bare surface theoretical model was inadequate, although the vegetation model appeared to be valid. Moisture parameters to correlate apparent temperature with soil moisture were compared.

  1. Oxidation, Creep And Fatigue Properties of Bare and Coated 31V alloy

    SciTech Connect

    Dryepondt, Sebastien N.; Jones, Samuel J.; Zhang, Ying; Maziasz, Philip J.; Pint, Bruce A.

    2014-12-06

    Increasing the efficiency of natural gas reciprocating engines will require materials with better mechanical and corrosion resistance at high temperatures. One solution to increase the lifetime of exhaust valves is to apply an aluminide coating to prevent corrosion assisted fatigue cracking, but the impact of the coating on the valve material mechanical properties needs to be assessed. Creep and high cycle fatigue (HCF) testing were conducted at 816°C on bare and slurry or pack-coated 31V alloy. After annealing according to the 31V standard heat treatment, the coated and bare creep specimens exhibited very similar creep rupture lives. The HCF behavior of the pack-coated alloy was close to the behavior of the bar alloy, but fatigue lifetimes of slurry-coated 31V specimens had higher variability. Aluminide coatings have the potential to improve the valve performance at high temperature, but the coating deposition process needs to be tailored for the substrate standard heat treatment.

  2. Effects of lidar point density on bare earth extraction and DEM creation

    NASA Astrophysics Data System (ADS)

    Puetz, Angela M.; Olsen, R. Chris; Anderson, Brian

    2009-05-01

    Data density has a crucial impact on the accuracy of Digital Elevation Models (DEMs). In this study, DEMs were created from a high point-density LIDAR dataset using the bare earth extraction module in Quick Terrain Modeler. Lower point-density LIDAR collects were simulated by randomly selecting points from the original dataset at a series of decreasing percentages. The DEMs created from the lower resolution datasets are compared to the original DEM. Results show a decrease in DEM accuracy as the resolution of the LIDAR dataset is reduced. Some analysis is made of the types of errors encountered in the lower resolution DEMs. It is also noted that the percentage of points classified as bare earth decreases as the resolution of the LIDAR dataset is reduced.

  3. Proposal to observe half-bare electrons on a 45-MeV linac

    NASA Astrophysics Data System (ADS)

    Trofymenko, S. V.; Shul'ga, N. F.; Delerue, N.; Jenzer, S.; Khodnevych, V.; Migayron, A.

    2017-07-01

    The experimental investigation of the transition radiation (TR) generated by a “half-bare” electron having the proper field different from the Coulomb one is proposed. The electrons in half-bare state are intended to be obtained in the result of their crossing of a conducting screen. We propose to investigate the influence of the half-bare state of electron in this process upon TR generated by such electron on a downstream OTR screen situated on some distance along the direction of the electron beam from the upstream screen which “undresses” the particle. Calculations are presented for the case of a 45 MeV linac and the distance between the screens in the region between 100 mm and 300 mm. The proposed experiment is expected to reveal new features of TR signal in such process comparing to previous measurements.

  4. A multi-frequency radiometric measurement of soil moisture content over bare and vegetated fields

    NASA Technical Reports Server (NTRS)

    Wang, J. R.; Schmugge, T. J.; Gould, W. I.; Glazar, W. S.; Fuchs, J. E.; Mcmurtrey, J. E., III

    1982-01-01

    An experiment on soil moisture remote sensing was conducted during July to September 1981 on bare, grass, and alfalfa fields at frequencies of 0.6, 1.4, 5.0, and 10.6 GHz with radiometers mounted on mobile towers. The results confirm the frequency dependence of sensitivity reduction due to the presence of vegetation cover. For the type of vegetated fields reported here, the vegetation effect is appreciable even at 0.6 GHz. Measurements over bare soil show that when the soil is wet, the measured brightness temperature is lowest at 5.0 GHz and highest at 0.6 GHz, a result contrary to the expectation based on the estimated dielectric permittivity of soil-water mixtures and the current radiative transfer model in that frequency range.

  5. Bone Marrow Transplantation

    MedlinePlus

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. ... platelets, which help the blood to clot. A bone marrow transplant is a procedure that replaces a person's ...

  6. Bone marrow culture

    MedlinePlus

    ... are very rare. Alternative Names Culture - bone marrow Images Bone marrow aspiration References Chernecky CC, Berger BJ. Bone marrow aspiration analysis-specimen (biopsy, bone marrow iron stain, iron stain, ...

  7. Bone biopsy (image)

    MedlinePlus

    A bone biopsy is performed by making a small incision into the skin. A biopsy needle retrieves a sample of bone and it ... examination. The most common reasons for bone lesion biopsy are to distinguish between benign and malignant bone ...

  8. Bone density scan (image)

    MedlinePlus

    A bone density scan measures the density of bone in a person. The lower the density of a bone the ... and whether any preventative treatment is needed. A bone density scan has the advantage of being painless and ...

  9. Infections of intravascular bare metal stents: a case report and review of literature.

    PubMed

    Bosman, W M P F; Borger van der Burg, B L S; Schuttevaer, H M; Thoma, S; Hedeman Joosten, P Ph

    2014-01-01

    The objective of the paper is to present a case of an infected bare metal stent in the left common iliac artery that was removed by an urgent operation, and to review the literature on diagnosis and outcome of infected coronary and non-coronary metal stents. A systematic search of the Medline database was performed with the purpose of identifying risk factors, signs and symptoms, imaging strategies, and treatment modalities of bare metal stent infections, both coronary and peripheral. In total, 76 additional studies/case reports (48 non-coronary; 29 coronary) were included and analyzed. Intravascular bare metal stent infections are a rare but serious complication, often leading to emergency surgery (overall: 75.3%; non-coronary cases: 83.3%; coronary cases: 62.1%). In 25.0% of the non-coronary cases, infection led to amputation of an extremity or removal of viscera. Reported mortality was up to 32.5% of the cases (non-coronary: 22.9%; coronary 48.3%). Physicians should always be suspicious of a stent infection when patients present with aspecific symptoms such as fever and chills after stent placement. Additional imaging can be used to detect the presence of a pseudoaneurysm. A PET-CT is an ideal medium for identification of a stent infection. Intravascular stent infection is associated with a high risk of morbidity and mortality. Surgery is the preferred treatment option, but not always possible, especially in patients with a coronary stent. In selected cases, bare metal stent infections may be prevented by the use of prophylactic antibiotics at stent placement. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  10. Optical coupling of bare optoelectronic components and flexographically printed polymer waveguides in planar optronic systems

    NASA Astrophysics Data System (ADS)

    Wang, Yixiao; Wolfer, Tim; Lange, Alex; Overmeyer, Ludger

    2016-05-01

    Large scale, planar optronic systems allowing spatially distributed functionalities can be well used in diverse sensor networks, such as for monitoring the environment by measuring various physical quantities in medicine or aeronautics. In these systems, mechanically flexible and optically transparent polymeric foils, e.g. polymethyl methacrylate (PMMA) and polyethylene terephthalate (PET), are employed as carrier materials. A benefit of using these materials is their low cost. The optical interconnections from light sources to light transmission structures in planar optronic systems occupy a pivotal position for the sensing functions. As light sources, we employ the optoelectronic components, such as edgeemitting laser diodes, in form of bare chips, since their extremely small structures facilitate a high integration compactness and ensure sufficient system flexibility. Flexographically printed polymer optical waveguides are deployed as light guiding structures for short-distance communication in planar optronic systems. Printing processes are utilized for this generation of waveguides to achieve a cost-efficient large scale and high-throughput production. In order to attain a high-functional optronic system for sensing applications, one of the most essential prerequisites is the high coupling efficiency between the light sources and the waveguides. Therefore, in this work, we focus on the multimode polymer waveguide with a parabolic cross-section and investigate its optical coupling with the bare laser diode. We establish the geometrical model of the alignment based on the previous works on the optodic bonding of bare laser diodes and the fabrication process of polymer waveguides with consideration of various parameters, such as the beam profile of the laser diode, the employed polymer properties of the waveguides as well as the carrier substrates etc. Accordingly, the optical coupling of the bare laser diodes and the polymer waveguides was simulated

  11. Paleomagnetism of the Miocene dikes in Bare Mountain, southwest Nevada: Implications for regional tectonics

    SciTech Connect

    Zhang, Y.; Gillett, S.L.; Karlin, R.E.; Schweickert, R.A. . Dept. of Geological Sciences)

    1993-04-01

    Paleomagnetic studies of N-striking Miocene quartz latite dikes (13.9 Ma), within Proterozoic and Paleozoic sedimentary rocks of Bare Mountain, have been conducted in an effort to determine the sense of post-middle Miocene tectonic tilting and rotation in the Bare Mountain region. A total of 56 oriented samples of dikes and wallrocks were collected from Tarantula Canyon (TC) and south of Joshua Hollow (JH), where the dikes intruded N-dipping Mississippian-Devonian limestone beds. Progressive thermal demagnetization and principal component analyses reveal a stable high temperature component of remanent magnetization that is carried by magnetite or hematite in different samples. Petrographic investigations, combined with thermal demagnetization analysis, indicate that magnetite is a primary phase and that hematite is secondary. Hematitic alteration in both wallrocks and dikes is probably hydrothermal following intrusion as the mean direction of both minerals overlap. The in situ mean magnetization directions from all dikes exhibit negative inclinations that correspond to a Tertiary reversed field. The data indicate that magnetization acquisition in the wallrocks and dikes postdates tilting of the beds and the no major remagnetization event has occurred since the intrusion. The results from TC imply that there has been no significant rotation of the northeast part of Bare Mountain since [minus]14 Ma. The authors further suggest that the E-W structural trends of Proterozoic and Paleozoic rocks at Bare Mountain are older than the middle Miocene dikes. Paleomagnetic data from dikes of JH show steeper inclinations and westerly declinations compared to the dike of TC. There are two interpretations to explain the differences: The dikes may have formed at different times in the same magmatic event and the directional differences are due to secular variation. Alternatively, the dikes at JH were tilted slightly to the north around a sub-horizontal axis.

  12. Towards new methodology for improvement of topographic and anisotropic correction of desert bare soil

    NASA Astrophysics Data System (ADS)

    Alomran, Ali

    Desert bare soil has been found in literature to exhibit anisotropic reflectance behaviour. Anisotropy is described by Bidirectional Reflectance Distribution function (BRDF). Literature studies have limited their investigations to the behaviour of the topographic corrections of Minnaert and C models (simple forms of the empirical type of BRDF) with terrain variables (slope and orientation). Yet, none of these studies, especially for desert bare soil, has investigated the behaviour of the coefficient values of Minnaert and C with terrain variables. The investigation in this study has revealed that the relation between terrain slope (derived from both DEM level-1 and level-2) of desert bare soil in Saudi Arabia and K and C values follow closely a 2nd order polynomial trend. K curves have taken convex shapes, whereas C curves were concave. The Minnaert (K) and C coefficients trends have shown that surface Lambertian behaviour is more pronounced on slopes facing away from the sun than on sun facing slopes. Unlike the Minnaert K and C coefficients derived from four spectral classes, this author's newly developed terrain slope, aspect and phase angle dependant's C and Minnaert coefficients produced promising results compared to the global K and C. Induced BRDF effects in the desert bare soil is found the more probable dominating cause for the scatter/jitter in the radiance/cos(i) regression plots that remained after radiometric correction. Though its high topographic correction efficiency and unlike Minnaert model, C model tends to maintain the uncorrected radiance values unchanged after correction (i.e. not amplified to compensate for low sun angle).

  13. Bare area of the spleen: a constant CT feature of the ascitic abdomen

    SciTech Connect

    Vibhakar, S.D.; Bellon, E.M.

    1984-05-01

    On computed tomographic (CT) scans of the abdomen in patients with ascites, there is one consistently recognizable area of the spleen that is not surrounded by fluid. This area, designated the bare area of the spleen, is related anatomically to the upper anterior part of the left kidney, specifically the Gerota fascia. Awareness of this relation enables differentiation of intraperitoneal fluid from pleural fluid on cross-sectional CT images.

  14. Gravitational waves from binary systems in circular orbits: convergence of a partially bare multipole expansion

    NASA Astrophysics Data System (ADS)

    Leonard, Stephen W.; Poisson, Eric

    1998-08-01

    The gravitational radiation originating from a compact binary system in circular orbit is usually expressed as an infinite sum over radiative multipole moments. In a slow-motion approximation, each multipole moment is expressed as a post-Newtonian expansion in powers of 0264-9381/15/8/002/img1, the ratio of the orbital velocity to the speed of light. The `bare multipole truncation' of the radiation consists in keeping only the leading-order (Newtonian) term in the post-Newtonian expansion of each moment, but summing over all the multipole moments. In the case of binary systems with small mass ratios, the bare multipole series was shown in a previous paper (Simone et al 1997 Class. Quantum Grav. 14 237) to converge for all values 0264-9381/15/8/002/img2, where e is the base of natural logarithms. (These include all physically relevant values for circular inspiral.) In this paper, we extend the analysis to a `partially bare multipole truncation' of the radiation, in which the leading-order moments are corrected with terms of relative order 0264-9381/15/8/002/img3 (first post-Newtonian, or 1PN, terms) and 0264-9381/15/8/002/img4 (1.5PN terms). We find that the partially bare multipole series also converges for all values 0264-9381/15/8/002/img2, and that it coincides (to within 1%) with the numerically `exact' results for 0264-9381/15/8/002/img6. Although this multipole series converges, it is an unphysical approximation, and the issue of the convergence of the true post-Newtonian series remains open. However, our analysis shows that an eventual failure of the true post-Newtonian series to converge cannot originate from summing over the Newtonian, 1PN and 1.5PN part of all the multipole moments.

  15. Transportable Waste-to-Energy System (TWES) Energy Recovery From Bare Base Waste

    DTIC Science & Technology

    2008-02-01

    removed and/or partially burned. Instead the furnace, coupled with a shredder , will completely burn the waste and provide heat for water or other...Photos from Ali Al Salem, AF bare base Nov 1998, FOUO-for official use only 8 8 TWES Fuel Processing Bulk Trash Shredder Shredded Fuel TWES Furnace...Program (FEMP) to initiate the conversion. • Will install and test electricity production at Tyndall AFB 15 15 TWES Process Diagram Shredders Useful

  16. Soft Landing of Bare Nanoparticles with Controlled Size, Composition, and Morphology

    SciTech Connect

    Johnson, Grant E.; Colby, Robert J.; Laskin, Julia

    2015-01-01

    A kinetically-limited physical synthesis method based on magnetron sputtering and gas aggregation has been coupled with size-selection and ion soft landing to prepare bare metal nanoparticles on surfaces with controlled coverage, size, composition, and morphology. Employing atomic force microscopy (AFM) and scanning electron microscopy (SEM), it is demonstrated that the size and coverage of bare nanoparticles soft landed onto flat glassy carbon and silicon as well as stepped graphite surfaces may be controlled through size-selection with a quadrupole mass filter and the length of deposition, respectively. The bare nanoparticles are observed with AFM to bind randomly to the flat glassy carbon surface when soft landed at relatively low coverage (1012 ions). In contrast, on stepped graphite surfaces at intermediate coverage (1013 ions) the soft landed nanoparticles are shown to bind preferentially along step edges forming extended linear chains of particles. At the highest coverage (5 x 1013 ions) examined in this study the nanoparticles are demonstrated with both AFM and SEM to form a continuous film on flat glassy carbon and silicon surfaces. On a graphite surface with defects, however, it is shown with SEM that the presence of localized surface imperfections results in agglomeration of nanoparticles onto these features and the formation of neighboring depletion zones that are devoid of particles. Employing high resolution scanning transmission electron microscopy in the high angular annular dark field imaging mode (STEM-HAADF) and electron energy loss spectroscopy (EELS) it is demonstrated that the magnetron sputtering/gas aggregation synthesis technique produces single metal particles with controlled morphology as well as bimetallic alloy nanoparticles with clearly defined core-shell structure. Therefore, this kinetically-limited physical synthesis technique, when combined with ion soft landing, is a versatile complementary method for preparing a wide range of

  17. Percutaneous Creation of Bare Intervascular Tunnels for Salvage of Thrombosed Hemodialysis Fistulas Without Recanalizable Outflow

    SciTech Connect

    Chen, Matt Chiung-Yu; Wang, Yen-Chi; Weng, Mei-Jui

    2015-08-15

    PurposeThis study aimed to retrospectively assess the efficacy of a bare intervascular tunnel for salvage of a thrombosed hemodialysis fistula. We examined the clinical outcomes and provided follow-up images of the bare intervascular tunnel.Materials and MethodsEight thrombosed fistulas lacked available recanalizable outflow veins were included in this study. These fistulas were salvaged by re-directing access site flow to a new outflow vein through a percutaneously created intervascular tunnel without stent graft placement. The post-intervention primary and secondary access patency rates were calculated using the Kaplan–Meier method.ResultsThe procedural and clinical success rates were 100 %. Post-intervention primary and secondary access patency at 300 days were 18.7 ± 15.8 and 87.5 ± 11.7 %, respectively. The mean follow-up period was 218.7 days (range 10–368 days). One patient died of acute myocardial infarction 10 days after the procedure. No other major complications were observed. Minor complications, such as swelling, ecchymosis, and pain around the tunnel, occurred in all of the patients.ConclusionsPercutaneous creation of a bare intervascular tunnel is a treatment option for thrombosed hemodialysis fistulas without recanalizable outflow in selected patients.

  18. Oceanic corrosion test of bare and zinc-protected aluminum alloys for seawater heat exchangers

    NASA Technical Reports Server (NTRS)

    Sasscer, D. S.; Morgan, T. O.; Rivera, C.; Ernst, R.; Scott, A. C.; Summerson, T. J.

    1982-01-01

    Bare 3004 tubes, 7072 Alclad 3004 tubes, and bare and zinc diffusion treated 3003 extrusions from a brazed aluminum, plate-fin heat exchanger were exposed to 1.8 m/sec flowing seawater aboard an open ocean test facility moored 3.4 km off the southeast coast of Puerto Rico. After six months exposure, the average corrosion rates for most varieties of aluminum materials converged to a low value of 0.015 mm/yr (0.6 mils/yr). Pitting did not occur in bare 3003 and 3004 samples during the six month test. Pitting did occur to varying degrees in the Alclad and zinc diffusion treated material, but did not penetrate to the base metal. Biofouling countermeasures (intermittent chlorination and brushing) did not affect the corrosion rates to any significant extent. Intermittent chlorination at a level of 0.5 ppm for 28 minutes daily controlled microbiofouling of the samples but did not prevent the development of a macrobiofouling community in areas of the plumbing with low flow.

  19. Bare Shear Viscosity and Anomalous Fall Rate of Oil Droplets in Nitrogen

    NASA Astrophysics Data System (ADS)

    Varley, Rodney

    2011-11-01

    Experimental evidence of Kim and Fedele (1982) indicates a breakdown of the Millikan Law for the fall rate of oil droplets in Nitrogen gas over a pressure range of 1-15 atm. The discrepancy is most pronounced for smallest, 0.1 micron radius droplets for which the fall rate increases with pressure. The opposite behavior was observed by Millikan with larger drops in air of pressure at most one atm. We explain these results by arguing that the particle's motion, in particular Stokes' drag formula, is determined by the so-called bare shear viscosity which applies to micro fluid flows. This is in contrast with the usual theory which uses a renormalized shear viscosity and which is well approximated by the Enskog value. A mode coupling formula for the bare shear viscosity is discussed and a graphical comparison is made with the experimental results. Basically an increase in gas pressure produces a decrease in the bare shear viscosity and thus the fall rate increases. The idea that the shear viscosity is smaller for micro flows is consistent with the intuitive belief that on small enough spatial and time scales, fluid flows are conservative without dissipation.

  20. Initial bacterial deposition on bare and zeolite-coated aluminum alloy and stainless steel.

    PubMed

    Chen, Gexin; Beving, Derek E; Bedi, Rajwant S; Yan, Yushan S; Walker, Sharon L

    2009-02-03

    In this study, the impact of zeolite thin film coatings on bacterial deposition and "biofouling" of surfaces has been investigated in an aqueous environment. The synthesis of two types of zeolite coatings, ZSM-5 coated on aluminum alloy and zeolite A coated on stainless steel, and the characterization of the coated and bare metal surfaces are described. The extent of cell deposition onto the bare and zeolite-coated aluminum alloy and stainless steel surfaces is investigated in a parallel plate flow chamber system under a laminar flow conditions. The initial rates of bacterial transfer to the various surfaces are compared by utilizing a marine bacterium, Halomonas pacifica g, under a range of ionic strength conditions. H. pacifica g deposited onto bare metal surfaces to a greater extent as compared with cells deposited onto the zeolite coatings. The surface properties found to have the most notable effect on attachment are the electrokinetic and hydrophobicity properties of the metal and zeolite-coated surfaces. These results suggest that a combination of two chemical mechanisms-hydrophobic and electrostatic interactions-contribute to the antifouling nature of the zeolite surface. Additional observations on the relative role of the hydrodynamic and physical phenomena are also discussed.

  1. An evaluation of the simulated bare soil evaporation of an atmospheric model

    NASA Astrophysics Data System (ADS)

    Schulz, Jan-Peter; Vogel, Gerd

    2016-04-01

    Land surface processes have a significant impact on near-surface atmospheric phenomena. They determine, among others, near-surface sensible and latent heat fluxes and the radiation budget, and thus influence atmosphere and land characteristics, such as temperature and humidity, the structure of the planetary boundary layer, and even cloud formation processes. It is therefore important to simulate the land surface processes in atmospheric models as realistically as possible. Verifications have shown that the bare soil evaporation computed by the land surface scheme TERRA of the COSMO atmospheric model is systematically overestimated. Since this flux is part of the surface water and energy balance it affects, for instance, the other components of the turbulent heat fluxes as well as the soil water content and the surface temperature. Data from the Meteorological Observatory Lindenberg of the German Meteorological Service were used to analyse this model behaviour. In the standard model configuration of TERRA, the formulation of bare soil evaporation is based on the Biosphere Atmosphere Transfer Scheme (BATS), following the work by R. E. Dickinson. In order to reduce the excessive evaporation simulated by BATS, other formulations for the bare soil evaporation were tested in TERRA. In turned out that a scheme based on a resistance formulation efficiently reduces the simulated vapour flux, leading to a better agreement with the measurements.

  2. Topographic accuracy assessment of bare earth lidar-derived unstructured meshes

    NASA Astrophysics Data System (ADS)

    Bilskie, Matthew V.; Hagen, Scott C.

    2013-02-01

    This study is focused on the integration of bare earth lidar (Light Detection and Ranging) data into unstructured (triangular) finite element meshes and the implications on simulating storm surge inundation using a shallow water equations model. A methodology is developed to compute root mean square error (RMSE) and the 95th percentile of vertical elevation errors using four different interpolation methods (linear, inverse distance weighted, natural neighbor, and cell averaging) to resample bare earth lidar and lidar-derived digital elevation models (DEMs) onto unstructured meshes at different resolutions. The results are consolidated into a table of optimal interpolation methods that minimize the vertical elevation error of an unstructured mesh for a given mesh node density. The cell area averaging method performed most accurate when DEM grid cells within 0.25 times the ratio of local element size and DEM cell size were averaged. The methodology is applied to simulate inundation extent and maximum water levels in southern Mississippi due to Hurricane Katrina, which illustrates that local changes in topography such as adjusting element size and interpolation method drastically alter simulated storm surge locally and non-locally. The methods and results presented have utility and implications to any modeling application that uses bare earth lidar.

  3. Bare below elbows: does this policy affect handwashing efficacy and reduce bacterial colonisation?

    PubMed

    Burger, A; Wijewardena, C; Clayson, S; Greatorex, R A

    2011-01-01

    UK Department of Health guidelines recommend that clinical staff are 'bare below the elbows'. There is a paucity of evidence to support this policy. One may hypothesise that absence of clothing around wrists facilitates more effective handwashing: this study aims to establish whether dress code affects bacterial colonisation before and after handwashing. Sixty-six clinical staff volunteered to take part in the study, noting whether they were bare below the elbows (BBE) or not bare (NB). Using a standardised technique, imprints of left and right fingers, palms, wrists and forearms were taken onto mini agar plates. Imprints were repeated after handwashing. After incubation, colonies per plate were counted, and subcultures taken. Thirty-eight staff were BBE and 28 were not. A total of 1112 plates were cultured. Before handwashing there was no significant difference in number of colonies between BBE and NB groups (Mann-Whitney, P < 0.05). Handwashing reduced the colony count, with greatest effect on fingers, palms and dominant wrists (t-test, P < 0.05). Comparing the two groups again after handwashing revealed no significant difference (Mann-Whitney, P < 0.05). Subcultures revealed predominantly skin flora. There was a large variation in number of colonies cultured. Handwashing resulted in a statistically significant reduction in colony count on fingers, palms and dominant wrist regardless of clothing. We conclude that handwashing produces a significant reduction in number of bacterial colonies on staff hands, and that clothing that is not BBE does not impede this reduction.

  4. Toward new methodology for improvement of topographic and anisotropic correction of desert bare soil

    NASA Astrophysics Data System (ADS)

    Alomran, Ali I.; McCullagh, M. J.

    2008-10-01

    Desert bare soil has been found in literature to exhibit anisotropic reflectance behaviour. Anisotropy is described by Bidirectional Reflectance Distribution function (BRDF). Literature studies have limited their investigations to the behaviour of the topographic corrections of Minnaert and C models (simple forms of the empirical type of BRDF) with terrain variables (slope and orientation). Yet, none of these studies, especially for desert bare soil, has investigated the behaviour of the coefficient values of Minnaert and C with terrain variables. The investigation in this study has revealed that the relation between terrain slope (derived from both DEM level-1 and level-2) of desert bare soil in Saudi Arabia and K and C values follow closely a 2nd order polynomial trend. K curves have taken convex shapes, whereas C curves were concave. The Minnaert (K) and C coefficients trends have shown that surface Lambertian behaviour is more pronounced on slopes facing away from the sun than on sun facing slopes. This author's newly developed terrain slope, aspect and phase angle dependant's C and Minnaert coefficients produced promising results compared to the global K and C.

  5. Oxidation, Creep and Fatigue Properties of Bare and Coated 31V Alloy

    NASA Astrophysics Data System (ADS)

    Dryepondt, Sebastien; Jones, Samuel J.; Zhang, Ying; Maziasz, Phillip J.; Pint, Bruce A.

    2015-01-01

    Increasing the efficiency of natural gas reciprocating engines will require materials with better mechanical and corrosion resistance at high temperatures. One solution to increase the lifetime of exhaust valves is to apply an aluminide coating to prevent corrosion assisted fatigue cracking, but the impact of the coating on the valve material mechanical properties needs to be assessed. In addition to cyclic oxidation testing in dry and humid air at 800°C, creep and high cycle fatigue (HCF) testing were conducted at 816°C on bare and slurry or pack-coated 31V alloy. The coated and bare creep specimens exhibited very similar creep rupture lives, as long as the specimens were annealed according to the 31V standard heat treatment before testing. The HCF behavior of the pack-coated alloy was close to the behavior of the bare alloy, but fatigue lifetimes of slurry-coated 31V specimens had higher variability. Aluminide coatings have the potential to improve the valve performance at high temperature, but the coating deposition process needs to be tailored for the substrate standard heat treatment.

  6. Patches of Bare Ground as a Staple Commodity for Declining Ground-Foraging Insectivorous Farmland Birds

    PubMed Central

    Schaub, Michael; Martinez, Nicolas; Tagmann-Ioset, Aline; Weisshaupt, Nadja; Maurer, Melanie L.; Reichlin, Thomas S.; Abadi, Fitsum; Zbinden, Niklaus; Jenni, Lukas; Arlettaz, Raphaël

    2010-01-01

    Conceived to combat widescale biodiversity erosion in farmland, agri-environment schemes have largely failed to deliver their promises despite massive financial support. While several common species have shown to react positively to existing measures, rare species have continued to decline in most European countries. Of particular concern is the status of insectivorous farmland birds that forage on the ground. We modelled the foraging habitat preferences of four declining insectivorous bird species (hoopoe, wryneck, woodlark, common redstart) inhabiting fruit tree plantations, orchards and vineyards. All species preferred foraging in habitat mosaics consisting of patches of grass and bare ground, with an optimal, species-specific bare ground coverage of 30–70% at the foraging patch scale. In the study areas, birds thrived in intensively cultivated farmland where such ground vegetation mosaics existed. Not promoted by conventional agri-environment schemes until now, patches of bare ground should be implemented throughout grassland in order to prevent further decline of insectivorous farmland birds. PMID:20949083

  7. Bare dorsal thoracic fascial flap for esophageal defects: an experimental study with dogs.

    PubMed

    Ugurlu, Kemal; Karsidag, Tamer; Huthut, Ilkay; Karsidag, Semra; Ozer, Kursat; Sacak, Bulent; Akcal, Arzu

    2012-06-01

    Reconstruction of esophageal defects has challenged reconstructive surgeons for a long time. Problems that affect the continuity of the orogastic tract influence the patient's quality of life and general health. Bare free fascial flaps are used to restore soft tissue defects of the oral cavity because they provide thin, pliable tissues with a high capacity for epithelialization to preserve the local anatomy. An experimental study was planned to investigate reconstruction of anterior cervical esophageal defects using a pedicled dorsal thoracic fascial flap. Eight hybrid dogs were used in the study. All operations were planned in three steps and performed with the animals under general anesthesia. For the two-layered reconstruction, the bare dorsal thoracic fascial flap was harvested and adapted like a patch to the defect. No partial or total flap loss was observed. On postoperative day 20 surgery, a complete epithelial lining on the same plane as the esophageal mucosa was observed over the flap tissue. A 4- to 5-mm longitudinal scar that did not form even a minimal stricture in any dog also was observed. No significant changes from postoperative day 20 to postoperative days 40 and 60 were observed. Bare fascial flaps in the oral cavity heal with spontaneous epithelialization and with no need for skin and mucosal grafts. Fascial flaps are easy to harvest and do not cause any functional loss because they are nonfunctional units. Their thin constitution helps the surgeon to shape the tissue and even form tubed flaps.

  8. Bone marker gene expression in calvarial bones: different bone microenvironments.

    PubMed

    Al-Amer, Osama

    2017-12-01

    In calvarial mice, mesenchymal stem cells (MSCs) differentiate into osteoprogenitor cells and then differentiate into osteoblasts that differentiate into osteocytes, which become embedded within the bone matrix. In this case, the cells participating in bone formation include MSCs, osteoprogenitor cells, osteoblasts and osteocytes. The calvariae of C57BL/KaLwRijHsD mice consist of the following five bones: two frontal bones, two parietal bones and one interparietal bone. This study aimed to analyse some bone marker genes and bone related genes to determine whether these calvarial bones have different bone microenvironments. C57BL/KaLwRijHsD calvariae were carefully excised from five male mice that were 4-6 weeks of age. Frontal, parietal, and interparietal bones were dissected to determine the bone microenvironment in calvariae. Haematoxylin and eosin staining was used to determine the morphology of different calvarial bones under microscopy. TaqMan was used to analyse the relative expression of Runx2, OC, OSX, RANK, RANKL, OPG, N-cadherin, E-cadherin, FGF2 and FGFR1 genes in different parts of the calvariae. Histological analysis demonstrated different bone marrow (BM) areas between the different parts of the calvariae. The data show that parietal bones have the smallest BM area compared to frontal and interparietal bones. TaqMan data show a significant increase in the expression level of Runx2, OC, OSX, RANKL, OPG, FGF2 and FGFR1 genes in the parietal bones compared with the frontal and interparietal bones of calvariae. This study provides evidence that different calvarial bones, frontal, parietal and interparietal, contain different bone microenvironments.

  9. Muscle training for bone strength.

    PubMed

    Suominen, Harri

    2006-04-01

    The main function of bone is to provide the mechanical integrity for locomotion and protection; accordingly, bone mass and architecture are adjusted to control the strains produced by mechanical load and muscular activity. Age-related patterns involve peak bone mass during growth, a plateau in adulthood, and bone loss during aging. The decline in bone mass and structural integrity results in increased risk of fractures, particularly in post-menopausal women. Athletes competing in strength and power events, such as weight-lifting and jumping, have superior bone mass and structure compared with their untrained counterparts in all age groups. Exercise seems to be most effective during rapid growth, the average gain in bone mineral content (BMC) and density (BMD) in controlled trials being of the order of 2-5% per year. The net gain of BMD after exercise interventions among older people is modest, at a level of 1-3% per year, but it is not clear whether positive effects can be maintained over a longer time. Although aerobic exercise is important in maintaining overall health, the resistance type of muscle training may be more applicable to the basic rules of bone adaptation and site-specific effects of exercise, have more favorable effects in maintaining or improving bone mass and architecture, and be safe and feasible for older people. It has been suggested that there is an opportunity for resistance training, for improved effects on BMD in postmenopausal women in bones which have less daily loading. In addition to BMC and BMD, bone geometry and mass distribution may also change as a result of training and other treatment, such as hormonal replacement therapy, thereby further improving bone strength and reducing fracture risk. Appropriate training regimens may reduce the risk of falls and the severity of fall-related injuries, and also constitute potential therapy to improve functional ability and the quality of life in osteoporotic patients. However, further research

  10. [Diagnostic imaging of bone metastases].

    PubMed

    Scutellari, P N; Addonisio, G; Righi, R; Giganti, M

    2000-12-01

    To present an "algorithm" for detection and diagnosis of skeletal metastases, which may be applied differently in symptomatic and asymptomatic cancer patients. February to March 1999 we randomly selected and retrospectively reviewed the clinical charts of 100 cancer patients (70 women and 30 men; mean age: 63 years, range: 55-87). All the patients had been staged according to TNM criteria and had undergone conventional radiography and bone scan; when findings were equivocal, CT and MRI had been performed too. The primary lesions responsible for bone metastases were sited in the: breast (51 cases), colon (30 cases: 17 men and 13 women), lung (7 cases: 6 men and 1 woman), stomach (4 cases: 2 men and 2 women), skin (4 cases: 3 men and 1 woman), kidney (2 men), pleura (1 woman), and finally liver (1 men). The most frequent radiographic pattern was the lytic type (52%), followed by osteosclerotic, mixed, lytic vs. mixed and osteosclerotic vs lytic patterns. The patients were divided into two groups: group A patients were asymptomatic and group B patients had local symptoms and/or pain. Skeletal metastases are the most common malignant bone tumors: the spine and the pelvis are the most frequent sites of metastasis, because of the presence of high amounts of red (hematopoietic active) bone marrow. Pain is the main symptom, even though many bone metastases are asymptomatic. Pathological fractures are the most severe consequences. With the algorithm for detection and diagnosis of skeletal metastases two different diagnostic courses are available for asymptomatic and symptomatic patients. Bone scintigraphy remains the technique of choice in asymptomatic patients in whom skeletal metastases are suspected. However this technique, though very sensitive, is poorly specific, and thus a negative bone scan finding is double-checked with another physical examination: if the findings remain negative, the diagnostic workup is over. On the contrary, in patients with a positive bone

  11. Remnant Woven Bone and Calcified Cartilage in Mouse Bone: Differences between Ages/Sex and Effects on Bone Strength

    PubMed Central

    Ip, Victoria; Toth, Zacharie; Chibnall, John; McBride-Gagyi, Sarah

    2016-01-01

    Introduction Mouse models are used frequently to study effects of bone diseases and genetic determinates of bone strength. Murine bones have an intracortical band of woven bone that is not present in human bones. This band is not obvious under brightfield imaging and not typically analyzed. Due to the band’s morphology and location it has been theorized to be remnant bone from early in life. Furthermore, lamellar and woven bone are well known to have differing mechanical strengths. The purpose of this study was to determine (i) if the band is from early life and (ii) if the woven bone or calcified cartilage contained within the band affect whole bone strength. Woven Bone Origin Studies In twelve to fourteen week old mice, doxycycline was used to label bone formed prior to 3 weeks old. Doxycycline labeling and woven bone patterns on contralateral femora matched well and encompassed an almost identical cross-sectional area. Also, we highlight for the first time in mice the presence of calcified cartilage exclusively within the band. However, calcified cartilage could not be identified on high resolution cone-beam microCT scans when examined visually or by thresholding methods. Mechanical Strength Studies Subsequently, three-point bending was used to analyze the effects of woven bone and calcified cartilage on whole bone mechanics in a cohort of male and female six and 13 week old Balb/C mice. Three-point bending outcomes were correlated with structural and compositional measures using multivariate linear regression. Woven bone composed a higher percent of young bones than older bones. However, calcified cartilage in older bones was twice that of younger bones, which was similar when normalized by area. Area and/or tissue mineral density accounted for >75% of variation for most strength outcomes. Percent calcified cartilage added significant predictive power to maximal force and bending stress. Calcified cartilage and woven bone could have more influence in genetic

  12. Micro-CT evaluation of bone defects: applications to osteolytic bone metastases, bone cysts, and fracture.

    PubMed

    Buie, Helen R; Bosma, Nick A; Downey, Charlene M; Jirik, Frank R; Boyd, Steven K

    2013-11-01

    Bone defects can occur in various forms and present challenges to performing a standard micro-CT evaluation of bone quality because most measures are suited to homogeneous structures rather than ones with spatially focal abnormalities. Such defects are commonly associated with pain and fragility. Research involving bone defects requires quantitative approaches to be developed if micro-CT is to be employed. In this study, we demonstrate that measures of inter-microarchitectural bone spacing are sensitive to the presence of focal defects in the proximal tibia of two distinctly different mouse models: a burr-hole model for fracture healing research, and a model of osteolytic bone metastases. In these models, the cortical and trabecular bone compartments were both affected by the defect and were, therefore, evaluated as a single unit to avoid splitting the defects into multiple analysis regions. The burr-hole defect increased mean spacing (Sp) by 27.6%, spacing standard deviation (SpSD) by 113%, and maximum spacing (Spmax) by 72.8%. Regression modeling revealed SpSD (β=0.974, p<0.0001) to be a significant predictor of the defect volume (R(2)=0.949) and Spmax (β=0.712, p<0.0001) and SpSD (β=0.271, p=0.022) to be significant predictors of the defect diameter (R(2)=0.954). In the mice with osteolytic bone metastases, spacing parameters followed similar patterns of change as reflected by other imaging technologies, specifically bioluminescence data which is indicative of tumor burden. These data highlight the sensitivity of spacing measurements to bone architectural abnormalities from 3D micro-CT data and provide a tool for quantitative evaluation of defects within a bone.

  13. Drug-eluting stents versus bare-metal stents for acute coronary syndrome.

    PubMed

    Feinberg, Joshua; Nielsen, Emil Eik; Greenhalgh, Janette; Hounsome, Juliet; Sethi, Naqash J; Safi, Sanam; Gluud, Christian; Jakobsen, Janus C

    2017-08-23

    Approximately 3.7 million people died from acute coronary syndrome worldwide in 2012. Acute coronary syndrome, also known as myocardial infarction or unstable angina pectoris, is caused by a sudden blockage of the blood supplied to the heart muscle. Percutaneous coronary intervention is often used for acute coronary syndrome, but previous systematic reviews on the effects of drug-eluting stents compared with bare-metal stents have shown conflicting results with regard to myocardial infarction; have not fully taken account of the risk of random and systematic errors; and have not included all relevant randomised clinical trials. To assess the benefits and harms of drug-eluting stents versus bare-metal stents in people with acute coronary syndrome. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, SCI-EXPANDED, and BIOSIS from their inception to January 2017. We also searched two clinical trials registers, the European Medicines Agency and the US Food and Drug Administration databases, and pharmaceutical company websites. In addition, we searched the reference lists of review articles and relevant trials. Randomised clinical trials assessing the effects of drug-eluting stents versus bare-metal stents for acute coronary syndrome. We included trials irrespective of publication type, status, date, or language. We followed our published protocol and the methodological recommendations of Cochrane. Two review authors independently extracted data. We assessed the risks of systematic error by bias domains. We conducted Trial Sequential Analyses to control the risks of random errors. Our primary outcomes were all-cause mortality, major cardiovascular events, serious adverse events, and quality of life. Our secondary outcomes were angina, cardiovascular mortality, and myocardial infarction. Our primary assessment time point was at maximum follow-up. We assessed the quality of the evidence by the GRADE approach. We included 25

  14. [Bone metastases].

    PubMed

    Vicent, S; Luis-Ravelo, D; Antón, I; Hernández, I; Martínez, S; de las Rivas, J; Gúrpide, A; Lecanda, F

    2006-01-01

    Bone metastases represent a devastating clinical problem in the most frequent neoplasies, especially in multiple myeloma, tumours breast, prostate and lung. The consequences include pain which is refractory to conventional analgesics, osteolysis often leading to bone-marrow compression and pathological fractures, and metabolic disorders. Recent advances in diagnosis using imaging techniques as well as different biochemical techniques have helped accurate diagnosis and follow-up. The increase in survival has improved through a multimodal approach combining, inhibition of osteolysis, with prophylactic orthopaedic surgery and radiation therapy. Recent advances in basic research have determined the molecular metastatic that can predict its proclivity to metastasize. Basic research will improve understanding of the basic mechanisms and lead to the clarification of molecular targets that will help in the development of medicines capable of preventing, decreasing or blocking the metastatic process.

  15. Bone image segmentation.

    PubMed

    Liu, Z Q; Liew, H L; Clement, J G; Thomas, C D

    1999-05-01

    Characteristics of microscopic structures in bone cross sections carry essential clues in age determination in forensic science and in the study of age-related bone developments and bone diseases. Analysis of bone cross sections represents a major area of research in bone biology. However, traditional approaches in bone biology have relied primarily on manual processes with very limited number of bone samples. As a consequence, it is difficult to reach reliable and consistent conclusions. In this paper we present an image processing system that uses microstructural and relational knowledge present in the bone cross section for bone image segmentation. This system automates the bone image analysis process and is able to produce reliable results based on quantitative measurements from a large number of bone images. As a result, using large databases of bone images to study the correlation between bone structural features and age-related bone developments becomes feasible.

  16. Architecture and microstructure of cortical bone in reconstructed canine mandibles after bone transport distraction osteogenesis.

    PubMed

    Zapata, Uriel; Halvachs, Emily K; Dechow, Paul C; Elsalanty, Mohammed E; Opperman, Lynne A

    2011-11-01

    Reconstruction of the canine mandible using bone transport distraction osteogenesis has been shown to be a suitable method for correcting segmental bone defects produced by cancer, gunshots, and trauma. Although the mechanical quality of the new regenerate cortical bone seems to be related to the mineralization process, several questions regarding the microstructural patterns of the new bony tissue remain unanswered. The purpose of this study was to quantify any microstructural differences that may exist between the regenerate and control cortical bone. Five adult American foxhound dogs underwent unilateral bone transport distraction of the mandible to repair bone defects of 30-35 mm. Animals were killed 12 weeks after the beginning of the consolidation period. Fourteen cylindrical cortical samples were extracted from the superior, medial, and inferior aspects of the lingual and buccal plates of the reconstructed aspect of the mandible, and 21 specimens were collected similarly from the contralateral aspect of the mandible. Specimens were evaluated using histomorphometric and micro-computed tomographic techniques to compare their microstructure. Except for differences in haversian canal area, histomorphometric analyses suggested no statistical differences in microstructure between regenerate and control cortical bone. Morphological evaluation suggested a consistent level of anisotropy, possibly related to the distraction vector. After 12 weeks' consolidation, bone created during bone transport distraction osteogenesis was comparable to native bone in microstructure, architecture, and mechanical properties. It is proposed that, after enough time, the properties of the regenerate bone will be identical to that of native bone.

  17. Bone Vascularization in Normal and Disease Conditions

    PubMed Central

    Carulli, Christian; Innocenti, Massimo; Brandi, Maria Luisa

    2013-01-01

    Bone vasculature is essential for many processes, such as skeletal development and growth, bone modeling and remodeling, and healing processes. Endothelium is an integral part of bone tissue, expressing a physiological paracrine function via growth factors and chemokines release, and interacting with several cellular lines. Alterations of the complex biochemical interactions between vasculature and bone cells may lead to various clinical manifestations. Two different types of pathologies result: a defect or an excess of bone vasculature or endothelium metabolism. Starting from the molecular basis of the interactions between endothelial and bone cells, the Authors present an overview of the recent acquisitions in the physiopathology of the most important clinical patterns, and the modern therapeutic strategies for their treatments. PMID:23986744

  18. Soy foods: are they useful for optimal bone health?

    PubMed Central

    2011-01-01

    Numerous studies have investigated the relationship between soy foods, soy protein, or isoflavone extracts and markers of bone health and osteoporosis prevention, and have come to conflicting conclusions. Research on dietary patterns, rather than on specific food ingredients or individual foods, may offer an opportunity for better understanding the role of soy foods in bone health. Evidence is reviewed regarding the question of whether soy foods contribute to a dietary pattern in humans that supports and promotes bone health. Soy foods are associated with improved markers of bone health and improved outcomes, especially among Asian women. Although the optimal amounts and types of soy foods needed to support bone health are not yet clear, dietary pattern evidence suggests that regular consumption of soy foods is likely to be useful for optimal bone health as an integral part of a dietary pattern that is built largely from whole plant foods. PMID:22870487

  19. Soy foods: are they useful for optimal bone health?

    PubMed

    Lanou, Amy J

    2011-12-01

    Numerous studies have investigated the relationship between soy foods, soy protein, or isoflavone extracts and markers of bone health and osteoporosis prevention, and have come to conflicting conclusions. Research on dietary patterns, rather than on specific food ingredients or individual foods, may offer an opportunity for better understanding the role of soy foods in bone health. Evidence is reviewed regarding the question of whether soy foods contribute to a dietary pattern in humans that supports and promotes bone health. Soy foods are associated with improved markers of bone health and improved outcomes, especially among Asian women. Although the optimal amounts and types of soy foods needed to support bone health are not yet clear, dietary pattern evidence suggests that regular consumption of soy foods is likely to be useful for optimal bone health as an integral part of a dietary pattern that is built largely from whole plant foods.

  20. Plastic embedding and polishing of bone for reflected light and electron microscopy.

    PubMed

    Wighton, A H J; Jones, Chris G; Bell, Lynne S

    2012-01-01

    The successful embedding of bone or any sample for reflected light or electron microscopy is crucial to the success of any analysis that might follow. Different materials present different embedding challenges, and here we discuss bone. Embedding is developed often as an adapted in-house protocol, and will vary from one institution to another, and is barely referenced in any detail in scientific papers. This chapter provides the protocol for bone that has proved successful at the Natural History Museum, both for reflected light and particularly for scanning electron microscopic examination.

  1. Molecular characterisation of growth differentiation factor 9 (gdf9) and bone morphogenetic protein 15 (bmp15) and their patterns of gene expression during the ovarian reproductive cycle in the European sea bass.

    PubMed

    Halm, S; Ibañez, A J; Tyler, C R; Prat, F

    2008-09-10

    Members of the transforming growth factor-beta superfamily, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15), have crucial roles in primary follicle growth in mammals. To initiate investigations into their significance in teleost oogenesis, we set out to clone and characterise the cDNAs of gdf9 and bmp15 and analysed their patterns of gene expression during the ovarian reproductive cycle in the European sea bass (Dicentrachus labrax). Sea bass gdf9 and bmp15 cDNAs were 2200 and 2049 bp long, coding for 438 and 459 amino acids (aas), respectively, and were most similar to zebrafish gdf9 and bmp15 (64.4 and 56.1%, respectively). By Northern analysis, sea bass gdf9 and bmp15 mRNA transcripts were detected in the ovary only of the tissues analysed and their sizes were 2.2 and 2.1 kb, respectively. Dot-blot analysis revealed high levels of gdf9 and bmp15 expression in the ovary during primary oocyte growth and previtellogenesis (July to October), with a significant decline at the onset of vitellogenesis (November) and remaining low until the beginning of new oocyte growth (April/May). There was a highly significant positive correlation (r=0.939) between gdf9 and bmp15 gene expression in individual samples. The high levels of gdf9 and bmp15 mRNA transcripts in the ovary, especially during the previtellogenic growth period suggest an important role for these factors in early primary oocyte growth in the European sea bass.

  2. Comparison of different methods of image analysis for quantifying bare soil in rangelands

    NASA Astrophysics Data System (ADS)

    Pulido Fernández, M.; Lavado Contador, J. F.; Schnabel, S.; Gómez Gutiérrez, Á.

    2009-04-01

    Many authors emphasize the importance of vegetation in maintaining low levels of soil loss by means of its positive influence in reducing erosion. In some low-vegetated Mediterranean rangelands, especially those with high livestock densities, water erosion can ultimately lead to a partial or total loss of soils, particularly at the beginning of the rainy season, when the surface cover is reduced after the dry summer period. In relation with this, it is essential to develop accurate methods allowing the quantification of bare soil which, in turn, can inform about the influence of different livestock management alternatives over the land system. The main goal of this work is the comparison of the ability of various pixel-based as well as object-oriented methods of image classification for the quantification of bare soil at a fine spatial resolution. The study area is a farm located in a woody rangeland (dehesa) in SW Spain covering a surface area of 1,024 hectare. A three bands (RGB) orthophoto image with a pixel size of 0,4 metres was used, together with its brightness component, to compare the classification of bare soil vs covered soil by means of the following methods: unsupervised classification (k-means algorithm), supervised classification (maximum likelihood classification, minimum distance or nearest neighbour and Mahalanobis distance) and object oriented classification through a multiresolution segmentation. The results of classification were tested using 700 to 1000 points of field validation. Different combinations of image layers as well as validation algorithms were applied to assess for the better classification results. The best unsupervised classification was obtained from a combination of the RGB layers with the brightness component of the image. A total of 93.1 % of the field data were correctly classified and the Area Under the Curve (AUC) obtained with the ROC (Receiving Operating Characteristic) validation technique amounted to 0.91. With this

  3. Autocorrelation analysis of bone structure.

    PubMed

    Rotter, M; Berg, A; Langenberger, H; Grampp, S; Imhof, H; Moser, E

    2001-07-01

    We propose a method called spatial autocorrelation analysis (SACA) to determine the spatial anisotropy of the trabecular bone in order to investigate osteoporosis. For demonstrating the potential of SACA we first evaluate the method on rectangular, simulated test patterns as a simple model for the anisotropic pore structure of the bone. As a next step towards biomedical application, photographic reference images of human vertebral bone were investigated by SACA. Osteoporotic bone structure could be clearly differentiated from non-osteoporotic sample images. Moreover, for demonstration of the applicability and potential of the method for in vivo characterization of osteoporosis, the microstructure of the human calcaneus was investigated by MR-microimaging on a young healthy male subject and an osteoporotic female. The measurements were performed using a high-field (3T) whole-body MR tomograph equipped with a special, strong head gradient system. The signal was acquired with a surface coil mounted on an in-house-built device for convenient immobilization of the subject's foot. Using a 3D gradient echo sequence a resolution of 0.254 x 0.254 x 2.188 mm3 was achieved in vivo. Selected images were inverted, gradient corrected for the inhomogeneous but sensitive detection by the surface coil, and subsequently analyzed by SACA. The anisotropy of bone structure detected by SACA is a possible candidate for noninvasive determination of the osteoporotic status, potentially complementing standard bone mineral density measurements. Copyright 2001 Wiley-Liss, Inc.

  4. Connecting Mechanics and Bone Cell Activities in the Bone Remodeling Process: An Integrated Finite Element Modeling

    PubMed Central

    Hambli, Ridha

    2014-01-01

    Bone adaptation occurs as a response to external loadings and involves bone resorption by osteoclasts followed by the formation of new bone by osteoblasts. It is directly triggered by the transduction phase by osteocytes embedded within the bone matrix. The bone remodeling process is governed by the interactions between osteoblasts and osteoclasts through the expression of several autocrine and paracrine factors that control bone cell populations and their relative rate of differentiation and proliferation. A review of the literature shows that despite the progress in bone remodeling simulation using the finite element (FE) method, there is still a lack of predictive models that explicitly consider the interaction between osteoblasts and osteoclasts combined with the mechanical response of bone. The current study attempts to develop an FE model to describe the bone remodeling process, taking into consideration the activities of osteoclasts and osteoblasts. The mechanical behavior of bone is described by taking into account the bone material fatigue damage accumulation and mineralization. A coupled strain–damage stimulus function is proposed, which controls the level of autocrine and paracrine factors. The cellular behavior is based on Komarova et al.’s (2003) dynamic law, which describes the autocrine and paracrine interactions between osteoblasts and osteoclasts and computes cell population dynamics and changes in bone mass at a discrete site of bone remodeling. Therefore, when an external mechanical stress is applied, bone formation and resorption is governed by cells dynamic rather than adaptive elasticity approaches. The proposed FE model has been implemented in the FE code Abaqus (UMAT routine). An example of human proximal femur is investigated using the model developed. The model was able to predict final human proximal femur adaptation similar to the patterns observed in a human proximal femur. The results obtained reveal complex spatio-temporal bone

  5. Connecting mechanics and bone cell activities in the bone remodeling process: an integrated finite element modeling.

    PubMed

    Hambli, Ridha

    2014-01-01

    Bone adaptation occurs as a response to external loadings and involves bone resorption by osteoclasts followed by the formation of new bone by osteoblasts. It is directly triggered by the transduction phase by osteocytes embedded within the bone matrix. The bone remodeling process is governed by the interactions between osteoblasts and osteoclasts through the expression of several autocrine and paracrine factors that control bone cell populations and their relative rate of differentiation and proliferation. A review of the literature shows that despite the progress in bone remodeling simulation using the finite element (FE) method, there is still a lack of predictive models that explicitly consider the interaction between osteoblasts and osteoclasts combined with the mechanical response of bone. The current study attempts to develop an FE model to describe the bone remodeling process, taking into consideration the activities of osteoclasts and osteoblasts. The mechanical behavior of bone is described by taking into account the bone material fatigue damage accumulation and mineralization. A coupled strain-damage stimulus function is proposed, which controls the level of autocrine and paracrine factors. The cellular behavior is based on Komarova et al.'s (2003) dynamic law, which describes the autocrine and paracrine interactions between osteoblasts and osteoclasts and computes cell population dynamics and changes in bone mass at a discrete site of bone remodeling. Therefore, when an external mechanical stress is applied, bone formation and resorption is governed by cells dynamic rather than adaptive elasticity approaches. The proposed FE model has been implemented in the FE code Abaqus (UMAT routine). An example of human proximal femur is investigated using the model developed. The model was able to predict final human proximal femur adaptation similar to the patterns observed in a human proximal femur. The results obtained reveal complex spatio-temporal bone

  6. Repair of Microdamage in Osteonal Cortical Bone Adjacent to Bone Screw

    PubMed Central

    Wang, Lei; Ye, Tingjun; Deng, Lianfu; Shao, Jin; Qi, Jin; Zhou, Qi; Wei, Li; Qiu, Shijing

    2014-01-01

    Up to date, little is known about the repair mode of microdamage in osteonal cortical bone resulting from bone screw implantation. In this study, self-tapping titanium cortical bone screws were inserted into the tibial diaphyses of 24 adult male rabbits. The animals were sacrificed at 1 day, 2 weeks, 1 month and 2 months after surgery. Histomorphometric measurement and confocal microscopy were performed on basic fuchsin stained bone sections to examine the morphological characteristics of microdamage, bone resorption activity and spatial relationship between microdamage and bone resorption. Diffuse and linear cracks were coexisted in peri-screw bone. Intracortical bone resorption was significantly increased 2 weeks after screw installation and reach to the maximum at 1 month. There was no significant difference in bone resorption between 1-month and 2-months groups. Microdamage was significantly decreased within 1 month after surgery. Bone resorption was predisposed to occur in the region of <100 µm from the bone-screw interface, where had extensive diffuse damage mixed with linear cracks. Different patterns of resorption cavities appeared in peri-screw bone. These data suggest that 1) the complex microdamage composed of diffuse damage and linear cracks is a strong stimulator for initiating targeted bone remodeling; 2) bone resorption activities taking place on the surfaces of differently oriented Haversian and Volkmann canals work in a team for the repair of extensive microdamage; 3) targeted bone remodeling is a short-term reaction to microdamage and thereby it may not be able to remove all microdamage resulting from bone screw insertion. PMID:24586702

  7. Ecotoxicity of bare and coated silver nanoparticles in the aquatic midge, Chironomus riparius.

    PubMed

    Park, Sun-Young; Chung, Jiwoong; Colman, Benjamin P; Matson, Cole W; Kim, Younghun; Lee, Byung-Cheon; Kim, Phil-Je; Choi, Kyunghee; Choi, Jinhee

    2015-09-01

    Although sediment is generally considered to be the major sink for nanomaterials in aquatic environments, few studies have addressed the ecotoxicity of nanomaterials in the presence of sediment. In the present study, the ecotoxicity of silver nanoparticles (AgNPs) with a range of organic coatings was examined in a freshwater sediment-dwelling organism, Chironomus riparius, using acute and chronic ecotoxicity endpoints, including molecular indicators. The toxicity of AgNPs coated with different organic materials, such as polyvinylpyrrolidone, gum arabic, and citrate, to C. riparius was compared with that of bare-AgNPs and AgNO3 (ionic silver). Total silver concentration was also measured to monitor the behavior of the AgNPs in water and sediment and to determine how ion dissolution affects the toxicity of all AgNPs. The coated- and bare-AgNPs caused DNA damage and oxidative stress-related gene expression. In addition, the bare-AgNPs and AgNO3 had a significant effect on development and reproduction. The surface coatings generally mitigated the toxicity of AgNPs to C. riparius, which can be explained by the reduced number of ions released from coated-AgNPs. Citrate-AgNPs caused the most significant alteration at the molecular level, but this did not translate to higher-level effects. Finally, comparing previously conducted studies on AgNP-induced gene expression without sediments, the authors show that the presence of sediment appears to mitigate the toxicity of AgNPs.

  8. Occupation of bare habitats, an evolutionary precursor to soil specialization in plants

    PubMed Central

    Cacho, N. Ivalú; Strauss, Sharon Y.

    2014-01-01

    Plant soil specialists contribute greatly to global diversity; however, the ecoevolutionary forces responsible for generating this diversity are poorly understood. We integrate molecular phylogenies with descriptive and experimental ecological data, creating a powerful framework with which to elucidate forces driving soil specialization. Hypotheses explaining edaphic specialization have historically focused on costs of adaptation to elements (e.g., nickel, calcium/magnesium) and accompanying tradeoffs in competitive ability in benign soils. We combine in situ microhabitat data for 37 streptanthoid species (Brassicaceae), soil analyses, and competition experiments with their phylogeny to reconstruct selective forces generating serpentine soil endemism, which has four to five independent origins in this group. Coupling ancestral state reconstruction with phylogenetic independent contrasts, we examine the magnitude and timing of changes in soil and habitat attributes relative to inferred shifts to serpentine. We find large changes in soil chemistry at nodes associated with soil shifts, suggesting that elemental changes occurred concomitantly with soil transitions. In contrast, the amount of bare ground surrounding plants in the field (“bareness”), which is greater in serpentine environments, is conserved across soil-type shifts. Thus, occupation of bare environments preceded shifts to serpentine, and may serve as an evolutionary precursor to harsh elemental soils and environments. In greenhouse experiments, taxa from barer environments are poorer competitors, a tradeoff that may contribute to soil endemism. The hypothesis of occupation of bare habitats as a precursor of soil specialization can be tested in other systems with a similar integrative ecophylogenetic approach, thereby providing deeper insights into this rich source of biodiversity. PMID:25267640

  9. Bare below elbows: does this policy affect handwashing efficacy and reduce bacterial colonisation?

    PubMed Central

    Burger, A; Wijewardena, C; Clayson, S; Greatorex, RA

    2010-01-01

    INTRODUCTION UK Department of Health guidelines recommend that clinical staff are ‘bare below the elbows’. There is a paucity of evidence to support this policy. One may hypothesise that absence of clothing around wrists facilitates more effective handwashing: this study aims to establish whether dress code affects bacterial colonisation before and after handwashing. SUBJECTS AND METHODS Sixty-six clinical staff volunteered to take part in the study, noting whether they were bare below the elbows (BBE) or not bare (NB). Using a standardised technique, imprints of left and right fingers, palms, wrists and forearms were taken onto mini agar plates. Imprints were repeated after handwashing. After incubation, colonies per plate were counted, and subcultures taken. RESULTS Thirty-eight staff were BBE and 28 were not. A total of 1112 plates were cultured. Before handwashing there was no significant difference in number of colonies between BBE and NB groups (Mann–Whitney, P < 0.05). Handwashing reduced the colony count, with greatest effect on fingers, palms and dominant wrists (t-test, P < 0.05). Comparing the two groups again after handwashing revealed no significant difference (Mann–Whitney, P < 0.05). Subcultures revealed predominantly skin flora. CONCLUSIONS There was a large variation in number of colonies cultured. Handwashing resulted in a statistically significant reduction in colony count on fingers, palms and dominant wrist regardless of clothing. We conclude that handwashing produces a significant reduction in number of bacterial colonies on staff hands, and that clothing that is not BBE does not impede this reduction. PMID:20727253

  10. [Amelioration of secondary bare alkali-saline patches in Songnen Plain through inserting cornstalk].

    PubMed

    He, Nianpeng; Wu, Ling; Jiang, Shicheng; Zhou, Daowei

    2004-06-01

    Based on the field experiment on Songnen grassland, a new method was established to ameliorate the secondary bare alkali-saline patches (SAP) through inserting cornstalk. The experiment was rested on the assumption that through inserting cornstalk in the secondary bare alkali-saline patches (SAP) to retain seeds moving over its surface, the necessary seed source could be gained; and these seeds should be able to germinate and survive successfully on the cornstalk itself or in its neighborhood, where should be more fit to grow than other sites in SAP, due to the decomposition of cornstalk and its special role, so that, the aim to restore vegetation of SAP could be achieved at a pretty low cost and rapid speed. The results showed that the seed bank in soil was increased significantly, owing to the inserted cornstalk and its operating processes. The seed number in ameliorated soil was 4020.0 +/- 1773.6 seeds x m(-2), while that in the secondary bare alkali-saline patches (SAP) was only 10.0 +/- 31.6 seeds x m(-2). Although the soil chemical and physical characters in ameliorated zone were improved to some extent, the overall situation of soil was still bad for plant growth, as the pH, soluble saline ion and organic matter were concerned. Most of Chloris virgata grew around or on the cornstalk, the plants around each cornstalk being 3.9 +/- 2.2, and the total being 48.64 +/- 38.72 g x m(-2). Therefore, this method demanded a few resources, and needed simple technology and low cost, which is potentially deserved to popularize.

  11. Outcomes of Prosthetic Hemodialysis Grafts after Deployment of Bare Metal versus Covered Stents at the Venous Anastomosis

    SciTech Connect

    Kim, Charles Y. Tandberg, Daniel J.; Rosenberg, Michael D.; Miller, Michael J.; Suhocki, Paul V.; Smith, Tony P.

    2012-08-15

    Purpose: To compare postintervention patency rates after deployment of bare metal versus covered stents across the venous anastomosis of prosthetic arteriovenous (AV) grafts. Methods: Review of our procedural database over a 6 year period revealed 377 procedures involving stent deployment in an AV access circuit. After applying strict inclusion criteria, our study group consisted of 61 stent deployments in 58 patients (median age 58 years, 25 men, 33 women) across the venous anastomosis of an upper extremity AV graft circuit that had never been previously stented. Both patent and thrombosed AV access circuits were retrospectively analyzed. Within the bare metal stent group, 20 of 32 AV grafts were thrombosed at initial presentation compared to 18 of 29 AV grafts in the covered stent group. Results: Thirty-two bare metal stents and 29 covered stents were deployed across the venous anastomosis. The 3, 6, and 12 months primary access patency rates for bare metal stents were not significantly different than for covered stents: 50, 41, and 22 % compared to 59, 52, and 29 %, respectively (p = 0.21). The secondary patency rates were also not significantly different: 78, 78, and 68 % for bare metal stents compared to 76, 69, and 61 % for covered stents, respectively (p = 0.85). However, covered stents demonstrated a higher primary stent patency rate than bare metal stents: 100, 85, and 70 % compared to 75, 67, and 49 % at 3, 6, and 12 months (p < 0.01). Conclusion: The primary and secondary access patency rates after deployment of bare metal versus covered stents at the venous anastomosis were not significantly different. However, bare metal stents developed in-stent stenoses significantly sooner.

  12. Engineering anatomically shaped human bone grafts.

    PubMed

    Grayson, Warren L; Fröhlich, Mirjam; Yeager, Keith; Bhumiratana, Sarindr; Chan, M Ete; Cannizzaro, Christopher; Wan, Leo Q; Liu, X Sherry; Guo, X Edward; Vunjak-Novakovic, Gordana

    2010-02-23

    The ability to engineer anatomically correct pieces of viable and functional human bone would have tremendous potential for bone reconstructions after congenital defects, cancer resections, and trauma. We report that clinically sized, anatomically shaped, viable human bone grafts can be engineered by using human mesenchymal stem cells (hMSCs) and a "biomimetic" scaffold-bioreactor system. We selected the temporomandibular joint (TMJ) condylar bone as our tissue model, because of its clinical importance and the challenges associated with its complex shape. Anatomically shaped scaffolds were generated from fully decellularized trabecular bone by using digitized clinical images, seeded with hMSCs, and cultured with interstitial flow of culture medium. A bioreactor with a chamber in the exact shape of a human TMJ was designed for controllable perfusion throughout the engineered construct. By 5 weeks of cultivation, tissue growth was evidenced by the formation of confluent layers of lamellar bone (by scanning electron microscopy), markedly increased volume of mineralized matrix (by quantitative microcomputer tomography), and the formation of osteoids (histologically). Within bone grafts of this size and complexity cells were fully viable at a physiologic density, likely an important factor of graft function. Moreover, the density and architecture of bone matrix correlated with the intensity and pattern of the interstitial flow, as determined in experimental and modeling studies. This approach has potential to overcome a critical hurdle-in vitro cultivation of viable bone grafts of complex geometries-to provide patient-specific bone grafts for craniofacial and orthopedic reconstructions.

  13. Single ionization and capture cross sections from biological molecules by bare projectile impact*

    NASA Astrophysics Data System (ADS)

    Quinto, Michele A.; Monti, Juan M.; Montenegro, Pablo D.; Fojón, Omar A.; Champion, Christophe; Rivarola, Roberto D.

    2017-02-01

    We report calculations on single differential and total cross sections for single ionization and single electron capture from biological targets, namely, vapor water and DNA nucleobasese molecules, by bare projectile impact: H+, He2+, and C6+. They are performed within the Continuum Distorted Wave - Eikonal Initial State approximation and compared to several existing experimental data. This study is oriented to the obtention of a reliable set of theoretical data to be used as input in a Monte Carlo code destined to micro- and nano- dosimetry.

  14. A radiative transfer model for microwave emissions from bare agricultural soils

    NASA Technical Reports Server (NTRS)

    Burke, W. J.; Paris, J. F.

    1975-01-01

    A radiative transfer model for microwave emissions from bare, stratified agricultural soils was developed to assist in the analysis of data gathered in the joint soil moisture experiment. The predictions of the model were compared with preliminary X band (2.8 cm) microwave and ground based observations. Measured brightness temperatures at vertical and horizontal polarizations can be used to estimate the moisture content of the top centimeter of soil with + or - 1 percent accuracy. It is also shown that the Stokes parameters can be used to distinguish between moisture and surface roughness effects.

  15. Long-term outcome of full plastic jacket treatment for bare metal in-stent restenosis.

    PubMed

    Jabbour, Richard J; Tanaka, Akihito; Mangieri, Antonio; Regazzoli, Damiano; Ancona, Marco; Pagnesi, Matteo; Giannini, Francesco; Latib, Azeem; Colombo, Antonio

    2017-03-01

    We report the long-term outcome of a case of "full plastic jacket" treatment consisting of three bioresorbable scaffolds to manage a subtotally occluded left anterior descending artery with associated severe bare metal in-stent restenosis. Angiography 36months' post procedure revealed an excellent result with negative fractional flow reserve result. Bioresorbable scaffolds may be an attractive option for in-stent restenosis due to the avoidance of an additional metallic layer, and this case is unusual regarding the total scaffold length used and long term angiographic follow-up. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. A numerical simulation of soil temperature and moisture variations for a bare field

    NASA Technical Reports Server (NTRS)

    Schieldge, J. P.; Kahle, A. B.; Alley, R. E.

    1982-01-01

    The diurnal variations of soil temperature and moisture content were simulated for a bare agricultural field in the San Joaquin Valley in California. The simulation pertained to the first 72 hours of drying, from saturation, of a sandy, clay loam soil. The results were compared with measurements of soil temperature and moisture content made at the field. Calculated and measured values of soil temperature trends agreed in general, but model results of moisture trends did not replicate observed diurnal effects evident at depths 4 centimeters or more below the surface.

  17. On the similarity between molecular electron densities, electrostatic potentials and bare nuclear potentials

    NASA Astrophysics Data System (ADS)

    Gadre, Shridhar R.; Bendale, Rajeev D.

    1986-10-01

    The similarities among the molecular contours of three scalar fields, viz. electron density (ED), electrostatic potential (ESP) and bare nuclear potential (BNP) have been investigated. The topological resemblance between ESP and ED contour diagrams (as prompted by the Thomas-Fermi model) is more pronounced than that for BNP and ED contour diagrams (as predicted by the local density functional model of Parr, Gadre and Bartolotti) with three-membered ring systems as test cases. An analysis of critical points of these distributions has also been included. Thus it may be conjectured that ED maps may prove useful in predicting reactive sites in molecules.

  18. Haptic roughness perception of linear gratings via bare finger or rigid probe.

    PubMed

    Lawrence, Michael A; Kitada, Ryo; Klatzky, Roberta L; Lederman, Susan J

    2007-01-01

    The magnitude of perceived roughness was haptically estimated as subjects freely explored linear gratings with either the bare finger or a rigid stylus-shaped probe. A considerably expanded range of ridge and groove width was investigated, relative to the extant literature. The four experiments collectively indicate that, for both finger and probe-end effectors, the variance in the estimates of perceived roughness was predominantly predicted by a single parameter: groove width. The functions relating perceived roughness to groove width increased over a narrow band relative to the full range of values, then flattened. These data have archival values for models of roughness perception involving both direct and indirect touch.

  19. A numerical simulation of soil temperature and moisture variations for a bare field

    NASA Technical Reports Server (NTRS)

    Schieldge, J. P.; Kahle, A. B.; Alley, R. E.

    1982-01-01

    The diurnal variations of soil temperature and moisture content were simulated for a bare agricultural field in the San Joaquin Valley in California. The simulation pertained to the first 72 hours of drying, from saturation, of a sandy, clay loam soil. The results were compared with measurements of soil temperature and moisture content made at the field. Calculated and measured values of soil temperature trends agreed in general, but model results of moisture trends did not replicate observed diurnal effects evident at depths 4 centimeters or more below the surface.

  20. The origins of French boxing: bare-knuckle duelling, savate and chausson, 1820-45.

    PubMed

    Loudcher, J F

    2001-01-01

    Savate, also called chausson, or French boxing is a combat activity characterized by kicking and punching. Its inception reaches back to the Restoration and the monarchy of Louis-Philippe (1818-48) although it was not recognised as a combat sport until the twentieth century. This article, based on a variety of rich sources (police reports, newspapers, books, etc.) demonstrates how, on the one hand, the origins of savate can be traced back to the bare-fisted duels of the Restoration and, on the other hand, its emergence corresponds to the mutation of structural order as put forth by M. Foucault.

  1. Interventional Treatment of LVAD Outflow Graft Stenosis by Introduction of Bare Metal Stents.

    PubMed

    Wiedemann, Dominik; Schlöglhofer, Thomas; Haberl, Thomas; Riebandt, Julia; Dimitrov, Kamen; Schima, Heinrich; Kastner, Johannes; Matzek, Wolfgang; Laufer, Günther; Zimpfer, Daniel

    2017-02-09

    LVAD outflow graft stenosis is a rare but life-threatening complication of MCS-therapy. Current treatment modalities (pump exchange or systemic thrombolytic therapy) are associated with significant mortality and morbidity.Implantation of bare metal stents within the stenosed outflow graft is an alternative. Herein we describe a series of 3-cases with successful stent placement. This seems to be safe and successful however correct and early diagnosis of outflow stenosis can be challenging. Information provided by the HeartWare HVAD logfiles are extremely helpful for diagnosis.

  2. The smile effect reduction of diode laser bar by bare bar curve control

    NASA Astrophysics Data System (ADS)

    Jia, Guannan; Yao, Shun; Luo, Xiaoying; Cheng, Jian; Wang, Zhiyong

    2017-02-01

    To reduce the diode laser bar's smile effect induced by packaging, a method based on a chip mounter is presented. When the bare bar is picked up by the pick-up tool (PUT) of the chip mounter, the curve direction and volume of the bar can be measured by scanning the P side surface of the bar with a laser rangefinder, and they can be controlled through adjusting the setting up of the PUT. By controlling the curve direction and volume at an appropriate state to compensate the packaging induced strain, the obtaining smile effect is restricted within 0.5μm steadily.

  3. Estimation of bare soil evaporation from a multi-frequency airborne SAR

    NASA Technical Reports Server (NTRS)

    Soares, Joao V.; Shi, Jiancheng; Hess, Laura; Engman, Edwin T.; Van Zyl, Jakob

    1992-01-01

    An experiment was performed with the NASA/JPL airborne radar polarimeter in Sept. 1989 in an agricultural area near Fresno, CA. Based on 1st-order surface backscattering models, a physically based algorithm for retrieval of soil moisture and surface roughness was developed. It is shown that copolarization ratio is sensitive to soil moisture but not to soil roughness at high incidence angles (between 40 and 60 deg). The derived soil moisture was employed to derive a two-layer heat and energy flux model to estimate evaporation from bare soils.

  4. Bare metal or drug-eluting stent implantation in last remaining vessel PCI? A serious dilemma.

    PubMed

    Zhang, Lei; Zhu, Jianhua; Kiemeneij, Ferdinand

    2009-04-01

    This case report describes the treatment of an old male diabetic patient with last remaining vessel coronary artery disease and poor left ventricular function. In presence of an old occlusion of the left main coronary artery, a subtotal stenosis of a dominant right coronary artery required angioplasty. After ample consideration it was decided to implant a bare metal stent (BMS) instead of a drug-eluting stent (DES). The major reason was the fear for early discontinuation of clopidogrel in case a drug-eluting stent was placed. The procedure and follow-up are described followed by an overview of current literature concerning similar pathology.

  5. Data documentation for the bare soil experiment at the University of Arkansas, June - August 1980

    NASA Technical Reports Server (NTRS)

    Sadeghi, A. M.

    1984-01-01

    The primary objective of this study is to evaluate the relationships between soil moisture and reflectivity of a bare soil, using microwave techniques. A drainage experiment was conducted on a Captina silt loam in cooperation with personnel in the Electrical Engineering Department. Measurements included soil moisture pressures at various depths, neutron probe measurements, gravimetric moisture samples, and reflectivity of the soil surface at selected frequencies including 1.5 and 6.0 GHz and at the incident angle of 45 deg. All measurements were made in conjuction with that of reflectivity data.

  6. Proximal Tibial Bone Graft

    MedlinePlus

    ... All Site Content AOFAS / FootCareMD / Treatments Proximal Tibial Bone Graft Page Content What is a bone graft? Bone grafts may be needed for various ... the proximal tibia. What is a proximal tibial bone graft? Proximal tibial bone graft (PTBG) is a ...

  7. Bone scan in metabolic bone diseases. Review.

    PubMed

    Abdelrazek, Saeid; Szumowski, Piotr; Rogowski, Franciszek; Kociura-Sawicka, Agnieszka; Mojsak, Małgorzata; Szorc, Małgorzata

    2012-08-25

    Metabolic bone disease encompasses a number of disorders that tend to present a generalized involvement of the whole skeleton. The disorders are mostly related to increased bone turnover and increased uptake of radiolabelled diphosphonate. Skeletal uptake of 99mTc-labelled diphosphonate depends primarily upon osteoblastic activity, and to a lesser extent, skeletal vascularity. A bone scan image therefore presents a functional display of total skeletal metabolism and has valuable role to play in the assessment of patients with metabolic bone disorders. However, the bone scan appearances in metabolic bone disease are often non-specific, and their recognition depends on increased tracer uptake throughout the whole skeleton. It is the presence of local lesions, as in metastatic disease, that makes a bone scan appearance obviously abnormal. In the early stages, there will be difficulty in evaluating the bone scans from many patients with metabolic bone disease. However, in the more severe cases scan appearances can be quite striking and virtually diagnostic.

  8. Bone scan appearances following bone and bone marrow biopsy

    SciTech Connect

    McKillop, J.H.; Maharaj, D.; Boyce, B.F.; Fogelman, I.

    1984-01-01

    Bone marrow and bone biopsies are performed not infrequently in patients referred for bone scans and represent a potential cause of a ''false positive'' focal abnormality on the bone scan. The authors have therefore examined the scan appearances in a series of patients who had undergone either sternal marrow biopsy, (Salah needle, diameter 1.2 mm) trephine iliac crest marrow biopsy (Jamshidi 11 gauge needle, diameter 3.5 mm) or a transiliac bone biopsy (needle diameter 8 mm). Of 18 patients studied 1 to 45 days after sternal marrow 17 had normal scan appearances at the biopsy site and 1 had a possible abnormality. None of 9 patients studied 4 to 19 days after trephine iliac crest marrow biopsy had a hot spot at the biopsy site. A focal scan abnormality was present at the biopsy site in 9/11 patients studied 5 to 59 days after a trans iliac bone biopsy. No resultant scan abnormality was seen in 4 patients imaged within 3 days of the bone biopsy or in 3 patients imaged 79 to 138 days after the procedure. Bone marrow biopsy of the sternum or iliac crest does not usually cause bone scan abnormalities. A focal abnormality at the biopsy site is common in patients imaged 5 days to 2 months after bone biopsy. The gauge of the needle employed in the biopsy and thus the degree of bone trauma inflicted, is likely to be main factor determining the appearance of bone scan abnormalities at the biopsy site.

  9. Genetic relationships between dagginess, breech bareness, and wool traits in New Zealand dual-purpose sheep.

    PubMed

    Pickering, N K; Blair, H T; Hickson, R E; Dodds, K G; Johnson, P L; McEwan, J C

    2013-10-01

    Genetic and phenotypic parameters were estimated for dagginess, breech, wool, and fiber traits from approximately 29,500 progeny born in 2009 and 2010 in New Zealand dual-purpose ram breeding sheep flocks. Dagginess is adherence of fecal matter to the wool, and this study investigates the genetic and phenotypic correlations between dagginess and breech and wool traits. Estimates for heritability were moderate (0.21 to 0.44) for the following traits: dag score at 3 and 8 mo (DAG3, DAG8), breech bareness, wool length, wool bulk (BULK), mean fiber diameter, mean fiber diameter SD, mean fiber diameter CV, curvature (CURV), weaning weight at 3 mo, and autumn BW. Heritability estimates for fleece weight at 12 mo and proportion of medullated fibers were high (0.49 and 0.53, respectively). Dag score at 3 mo and DAG8 had low genetic and phenotypic correlations with all traits. Breech bareness had positive genetic and phenotypic correlations with CURV and BULK and mostly negative genetic correlations with all other wool traits. In summary the quantity and attributes of wool were not primary causative factors in fecal accumulation, leaving fecal consistency and composition as the major factors.

  10. Oxidation, Creep And Fatigue Properties of Bare and Coated 31V alloy

    DOE PAGES

    Dryepondt, Sebastien N.; Jones, Samuel J.; Zhang, Ying; ...

    2014-12-06

    Increasing the efficiency of natural gas reciprocating engines will require materials with better mechanical and corrosion resistance at high temperatures. One solution to increase the lifetime of exhaust valves is to apply an aluminide coating to prevent corrosion assisted fatigue cracking, but the impact of the coating on the valve material mechanical properties needs to be assessed. Creep and high cycle fatigue (HCF) testing were conducted at 816°C on bare and slurry or pack-coated 31V alloy. After annealing according to the 31V standard heat treatment, the coated and bare creep specimens exhibited very similar creep rupture lives. The HCF behaviormore » of the pack-coated alloy was close to the behavior of the bar alloy, but fatigue lifetimes of slurry-coated 31V specimens had higher variability. Aluminide coatings have the potential to improve the valve performance at high temperature, but the coating deposition process needs to be tailored for the substrate standard heat treatment.« less

  11. Laser damage of HR, AR-coatings, monolayers and bare surfaces at 1064 nm

    NASA Technical Reports Server (NTRS)

    Garnov, S. V.; Klimentov, S. M.; Said, A. A.; Soileau, M. J.

    1993-01-01

    Laser induced damage thresholds and morphologies were investigated in a variety of uncoated and coated surfaces, including monolayers and multi-layers of different chemical compositions. Both antireflective (AR) and highly reflective (HR) were tested. Testing was done at 1064 nm with 25 picosecond and 8 nanosecond YAG/Nd laser single pulses. Spot diameter in the experiments varied from 0.09 to 0.22 mm. The laser damage measurement procedure consisted of 1-on-1 (single laser pulse in the selected site) and N-on-1 experiments including repeated irradiation by pulses of the same fluence and subsequently raised from pulse to pulse fluence until damage occurred. The highest picosecond damage thresholds of commercially available coatings averaged 12 - 14 J/sq cm, 50 percent less than thresholds obtained in bare fused silica. Some coatings and bare surfaces revealed a palpable preconditioning effect (an increase in threshold of 1.2 to 1.8 times). Picosecond and nanosecond data were compared to draw conclusions about pulse width dependence. An attempt was made to classify damage morphologies according to the type of coating, class of irradiating, and damage level.

  12. Gamma-ray bursts and the birthrate of bare neutron stars

    NASA Technical Reports Server (NTRS)

    Ramaty, R.; Dar, A.; Nussinov, S.; Kozlovsky, B.

    1992-01-01

    Accretion of matter onto the surface of a white dwarf in a binary system can push it over the Chandrasekhar mass limit and may cause it to collapse into a neutron star without mass ejection or with the ejection of only a small mass. Such an optically quiet stellar collapse should be accompanied by a neutrino burst which could be detected with underground neutrino detectors if the collapse took place in our own Galaxy or in very close nearby galaxies. However, the frequency of such collapses is not known. Here we show that, if the ejected mass is less than 3 x 10 exp -4 solar mass, the electron-positron pairs resulting from neutrino-antineutrino annihilations outside the neutrinosphere produce a gamma-ray burst which could be observed out to distances of at least 300 Mpc, and that the observed rate of gamma-ray bursts sets stringent upper limits on the frequency of bare or nearlly bare neutron star births.

  13. Similar Success Rates with Bivalirudin and Unfractionated Heparin in Bare-Metal Stent Implantation

    SciTech Connect

    Hallak, Omar; Shams, S. Ali; Broce, Mike; Lavigne, P. Scott; Lucas, B. Daniel; Elhabyan, Abdul-Karim; Reyes, Bernardo J.

    2007-09-15

    Background. Unfractionated heparin (UFH) is the traditional agent utilized during percutaneous peripheral interventions (PPIs) despite its well-known limitations. Bivalirudin, a thrombin-specific anticoagulant, overcomes many of the limitations of UFH and has consistently demonstrated comparable efficacy with significantly fewer bleeding complications. The purpose of this study was to compare procedural success in patients undergoing bare-metal stent implantation for atherosclerotic blockage of the renal, iliac, and femoral arteries and receiving either bivalirudin (0.75 mg/kg bolus/1.75 mg/kg/hr infusion) or UFH (50-70 U/kg/hr bolus) as the primary anticoagulant. Methods. This study was an open-label, nonrandomized retrospective registry with the primary endpoint of procedural success. Secondary endpoints included incidence of: death, myocardial infarction (MI), urgent revascularization, amputation, and major and minor bleeding. Results. One hundred and five consecutive patients were enrolled (bivalirudin = 53; heparin = 52). Baseline demographics were comparable between groups. Patients were pretreated with clopidogrel (approx. 71%) and aspirin (approx. 79%). Procedural success was achieved in 97% and 96% of patients in the bivalirudin- and heparin-treated groups, respectively. Event rates were low and similar between groups. Conclusion. Bivalirudin maintained an equal rate of procedural success in this cohort without sacrificing patient safety. Results of this study add to the growing body of evidence supporting the safety and efficacy of bivalirudin as a possible substitute for UFH in anticoagulation during peripheral vascular bare-metal stent implantation.

  14. Oralloy (93.2 235U) Bare Metal Annuli And Disks

    SciTech Connect

    Hummel, Andrew John

    2015-09-01

    A multitude of critical experiments with highly enriched uranium metal were conducted in the 1960s and 1970s at the Oak Ridge Critical Experiments Facility (ORCEF) in support of criticality safety operations at the Y-12 Plant. These experiments served to evaluate the storage, casting, and handling limits for the Y-12 Plant while also providing data for verification of different calculation methods and associated cross-sections for nuclear criticality safety applications. These included both solid cylinders and annuli of various diameters, interacting cylinders of various diameters, parallelepipeds, and reflected cylinders and annuli. The experiments described here involve a series of delayed critical stacks of bare oralloy HEU annuli and disks. Three of these experiments consist of stacking bare HEU annuli of varying diameters to obtain critical configurations. These annuli have nominal inner and outer diameters (ID/OD) including: 7 inches (") ID – 9" OD, 9" ID – 11" OD, 11" ID – 13" OD, and 13? ID – 15" OD. The nominal heights range from 0.125" to 1.5". The three experiments themselves range from 7" – 13", 7" – 15", and 9" – 15" in diameter, respectively. The fourth experiment ranges from 7" – 11", and along with different annuli, it also includes an 11" disk and several 7" diameter disks. All four delayed critical experiments were configured and evaluated by J. T. Mihalczo, J. J. Lynn, and D. E. McCarty from December of 1962 to February 1963 with additional information in their corresponding logbook.

  15. Microwave remote sensing of soil moisture content over bare and vegetated fields

    NASA Technical Reports Server (NTRS)

    Wang, J. R.; Shiue, J. C.; Mcmurtrey, J. E., III

    1980-01-01

    Remote measurements of soil moisture contents over bare fields and fields covered with orchard grass, corn, and soybean were made during October 1979 with 1.4 GHz and 5 GHz microwave radiometers mounted on a truck. Ground truth of soil moisture content, ambient air, and soil temperatures was acquired concurrently with the radiometric measurements. The biomass of the vegetation was sampled about once a week. The measured brightness temperatures over bare fields were compared with those of radiative transfer model calculations using as inputs the acquired soil moisture and temperature data with appropriate values of dielectric constants for soil-water mixtures. Good agreement was found between the calculated and the measured results over 10-70 deg incident angles. The presence of vegetation was found to reduce the sensitivity of soil moisture sensing. At 1.4 GHz the sensitivity reduction ranged from approximately 20% for 10-cm tall grassland to over 60% for the dense soybean field. At 5 GHz the corresponding reduction in sensitivity ranged from approximately 70 to approximately 90%.

  16. Preliminary study of quaternary faulting on the east side of Bare Mountain, Nye County, Nevada

    SciTech Connect

    Reheis, M.C.

    1986-12-31

    Active faults bound the east side of Bare Mountain. Geomorphic features, stratigraphy, and soil development indicate that two 3-km-long segments of the range-front fault probably last moved in Holocene or late Pleistocene time. Other segments of the fault have been quiescent since the late Pleistocene. Both late Pleistocene and Holocene deposits bury many faults east of the northern end of Bare Mountain. Two prospect pits on the range-front fault reveal evidence of recurrent late Quaternary movements. Both older and younger deposits in one pit are faulted, but fractures in the older unit do not extend up into the younger unit. Based on soil development, the older and younger fault episodes respectively are probably late Pleistocene and Holocene in age. Another pit shows carbonate-cemented fractures with slickensides in a late Pleistocene deposit, suggesting at least two late Pleistocene or Holocene fault movements. Middle to early Pleistocene and Tertiary deposits show evidence of recurrent faulting in many locations. Faults in these deposits are pervaded by secondary CaCO{sub 3} and silica that commonly exhibit slickensides.

  17. Ultrasonic Guided Wave Focus Inspection Potential of Bare and Coated Pipes

    NASA Astrophysics Data System (ADS)

    Mu, J.; Hua, J.; Rose, J. L.

    2010-02-01

    Ultrasonic guided waves in elastic bare pipes are studied from a theoretical point of view. Dispersion curves of both axisymmetric and non-axisymmetric waves are presented. The parameters of 4-channel focusing are calculated by a phased array focusing algorithm. Experimentally four defects are detected in a cased pipe inspection. The defect probability of detection is highly improved by applying the phased array focusing technique. Guided wave dispersion curves in coated pipes are calculated using a 1-D Semi-Analytical Finite Element (SAFE) technique. This theoretically driven hybrid SAFE method has perfectly tackled the guided wave problem in coated pipes, including dispersion curves (phase velocity dispersion curves and attenuation dispersion curves) and wave structures. The time delays and amplitudes of the 8-channel focusing in an 8 in sch40 coated pipe are calculated by the SAFE algorithm and input to the FEM simulation in ABAQUS®. Focusing performance is improved up to 67% by applying the coated pipe parameters compared with the bare pipe parameters.

  18. Optical properties of plasmon-resonant bare and silica-coated nanostars used for cell imaging.

    PubMed

    Bibikova, Olga; Popov, Alexey; Bykov, Alexander; Prilepskii, Artur; Kinnunen, Matti; Kordas, Krisztian; Bogatyrev, Vladimir; Khlebtsov, Nikolai; Vainio, Seppo; Tuchin, Valery

    2015-07-01

    We synthesized and characterized gold nanostars and their silica-coated derivatives with 7- to 50-nm shell thicknesses as contrast agents for optical imaging. The scattering and absorption coefficients of the nanoparticles (NPs) were estimated by means of collimated transmittance and diffuse reflectance/transmittance analyses. The contrasting properties of the nanostructures were studied in optical coherence tomography glass capillary imaging. The silica-coated nanostars with the thickest shell have higher scattering ability in comparison with bare nanostars. Viability assays confirmed weak in vitro toxicity of nanostructures at up to ∼200-μg/mL concentrations. We showed real-time visualization of nanostars in both agarose and cultured cells by analyzing the backscattering signal using a conventional laser confocal microscope. The signal intensity detected from the silica-coated NPs was almost 1.5 times higher in comparison with bare nanostars. To the best of our knowledge, this is the first time that conventional laser confocal microscopy was applied in combined scattering and transmitted light modes to detect the backscattered signal of gold nanostars, which is useful for direct monitoring of the uptake, translocation, and accumulation of NPs in living cells.

  19. Necrotizing meningoencephalitis caused by Sarcocystis falcatula in bare-faced ibis (Phimosus infuscatus).

    PubMed

    Konradt, Guilherme; Bianchi, Matheus Viezzer; Leite-Filho, Ronaldo Viana; da Silva, Bruna Zafalon; Soares, Rodrigo Martins; Pavarini, Saulo Petinatti; Driemeier, David

    2017-02-01

    The infection by S. falcatula is commonly associated with respiratory disease in captive psittacine birds, with a few case reports of this protozoan causing encephalitis in wild birds. We describe the clinical, pathological, and molecular aspects of an infection by S. falcatula in a bare-faced ibis (Phimosus infuscatus). Clinically, wing paralysis and mild motor incoordination were observed. At necropsy, the telencephalic cortex showed multifocal to coalescing yellowish soft areas. Histologically, multifocal to coalescent nonsuppurative necrotizing meningoencephalitis of telencephalic cortex, cerebellum, and brainstem was observed. Necrotic areas showed multiple protozoan organism characteristics of Sarcocystis sp. schizonts in the cytoplasm of endothelial cells or lying free in the neuropil. Partial genetic sequences of the gene encoding cytochrome b (CYTB), the gene encoding the beta subunit of RNA polymerase (RPOB) and the first internal transcribed spacer (ITS-1) from Sarcocystis sp. schizonts revealed that the parasite had ITS-1 sequences that were 100% identical to the homologous alleles from Sarcocystis sp. shed by Didelphis albiventris in Brazil. RPOB and CYTB sequences were 100% identical to homologous of S. falcatula available in Genbank. Thus, this is the first report of necrotizing meningoencephalitis caused by S. falcatula in bare-faced ibis (P. infuscatus).

  20. Drug-eluting versus bare-metal coronary stents: where are we now?

    PubMed

    Amoroso, Nicholas S; Bangalore, Sripal

    2012-11-01

    Drug-eluting stents have dramatically reduced the risk of restenosis, but concerns of an increased risk of stent thrombosis have provided uncertainty about their use. Recent studies have continued to show improved procedural and clinical outcomes with drug-eluting stents both in the setting of acute coronary syndromes and stable coronary artery disease. Newer generation drug-eluting stents (especially everolimus-eluting stents) have been shown to be not only efficacious but also safe with reduced risk of stent thrombosis when compared with bare-metal stents, potentially changing the benchmark for stent safety from bare-metal stents to everolimus-eluting stents. While much progress is being made in the development of bioabsorbable polymer stents, nonpolymer stents and bioabsorbable stent technology, it remains to be seen whether these stents will have superior safety and efficacy outcomes compared with the already much improved rates of revascularization and stent thrombosis seen with newer generation stents (everolimus-eluting stents and resolute zotarolimus-eluting stents).

  1. Trajectories of water table recovery following the re-vegetation of bare peat

    NASA Astrophysics Data System (ADS)

    Shuttleworth, Emma; Evans, Martin; Allott, Tim; Maskill, Rachael; Pilkington, Michael; Walker, Jonathan

    2016-04-01

    The hydrological status of blanket peat influences a wide range of peatland functions, such as runoff generation, water quality, vegetation distribution, and rates of carbon sequestration. The UK supports 15% of the world's blanket peat cover, but much of this vital resource is significantly degraded, impacted by industrial pollution, overgrazing, wildfire, and climatic shifts. These pressures have produced a unique landscape characterised by severe gully erosion and extensive areas of bare peat. This in turn has led water tables to become substantially drawn down, impacting peatland function and limiting the resilience of these landscapes to future changes in climate. The restoration of eroding UK peatlands is a major conservation concern, and landscape-scale interventions through the re-vegetation of bare peat is becoming increasingly extensive in areas of upland Britain. Water table is the primary physical parameter considered in the monitoring of many peatland restoration projects, and there is a wealth of data on individual monitoring programmes which indicates that re-vegetation significantly raises water tables. This paper draws on data from multiple restoration projects carried out by the Moors for the Future Partnership in the Southern Pennines, UK, covering a range of stages in the erosion-restoration continuum, to assess the trajectories of water table recovery following re-vegetation. This will allow us to generate projections of future water table recovery, which will be of benefit to land managers and conservation organisations to inform future restoration initiatives.

  2. Discovery Of Transient Iron Fluorescence In The Bare Seyfert Ark 120

    NASA Astrophysics Data System (ADS)

    Nardini, Emanuele; Porquet, D.; Reeves, J.; Braito, V.; Lobban, A.; Matt, G.

    2016-10-01

    We present the results from an X-ray observational campaign on the bare Seyfert galaxy Ark 120 jointly carried out with XMM- Newton, Chandra, and NuSTAR. The favourable line of sight to this source, devoid of any significant absorbing material, provides an incomparably clean view to the nuclear regions of an AGN, down to the the immediate surroundings of the radiatively efficient, accreting supermassive black hole. Here we focus on the nature, properties, and variability of the emission-line complex due to iron fluorescence detected in the 6-7 keV band. The narrow K-alpha feature from neutral iron at 6.4 keV is resolved by Chandra/HETG to a width of 5000 km/s, consistent with origin from the optical broad-line region. However, excess components are seen on both sides of this core. The excess emission map computed over the 7.5 days of XMM-Newton monitoring and the following, time-resolved spectral analysis show that both the red and blue features are highly variable on timescales of 10-15 hours. Any explanation (orbiting hotspots, coronal clumps, disc instabilities) requires a highly dynamic, inhomogeneous disc/coronal system. These observations thus prove the unique potential of a bare source like Ark 120 to better understand the physics of the accretion disc/X-ray corona system in AGN.

  3. Imparting Barely Visible Impact Damage to a Stitched Composite Large-Scale Pressure Box

    NASA Technical Reports Server (NTRS)

    Lovejoy, Andrew E.; Przekop, Adam

    2016-01-01

    The Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) is a concept that was developed by The Boeing Company to address the complex structural design aspects associated with a pressurized hybrid wing body (HWB) aircraft configuration, which has been a focus of the NASA Environmentally Responsible Aviation Project. The NASA-Boeing structural development for the HWB aircraft culminated in testing of the multi-bay box, which is an 80%-scale representation of the pressurized center-body section. This structure was tested in the NASA Langley Research Center Combined Loads Test System facility. As part of this testing, barely visible impact damage was imparted to the interior and exterior of the test article to demonstrate compliance with a condition representative of the requirements for Category 1 damaged composite structure as defined by the Federal Aviation Regulations. Interior impacts were imparted using an existing spring-loaded impactor, while the exterior impacts were imparted using a newly designed, gravity-driven impactor. This paper describes the impacts to the test article, and the design of the gravitydriven guided-weight impactor. The guided-weight impactor proved to be a very reliable method to impart barely visible impact damage in locations which are not easily accessible for a traditional drop-weight impactor, while at the same time having the capability to be highly configurable for use on other aircraft structures.

  4. Clinical utility of platinum chromium bare-metal stents in coronary heart disease

    PubMed Central

    Jorge, Claudia; Dubois, Christophe

    2015-01-01

    Coronary stents represent a key development for the treatment of obstructive coronary artery disease since the introduction of percutaneous coronary intervention. While drug-eluting stents gained wide acceptance in contemporary percutaneous coronary intervention practice, further developments in bare-metal stents remain crucial for patients who are not candidates for drug-eluting stents, or to improve metallic platforms for drug elution. Initially, stent platforms used biologically inert stainless steel, restricting stent performance due to limitations in flexibility and strut thickness. Later, cobalt chromium stent alloys outperformed steel as the material of choice for stents, allowing latest generation stents to be designed with significantly thinner struts, while maintaining corrosion resistance and radial strength. Most recently, the introduction of the platinum chromium alloy refined stent architecture with thin struts, high radial strength, conformability, and improved radiopacity. This review will provide an overview of the novel platinum chromium bare-metal stent platforms available for coronary intervention. Mechanical properties, clinical utility, and device limitations will be summarized and put into perspective. PMID:26345228

  5. Chernozem aggregate waterstability loss investigation in a long-term bare fallow experiment

    NASA Astrophysics Data System (ADS)

    Vasilyeva, N. A.; Milanovskiy, E. Y.

    2009-04-01

    The research is focused on mechanisms of aggregate waterstability controlled by soil organic matter (SOM). The objects of the research are two contrast variants of typical chernozem - under native grassland and under a 60-year bare fallow experimental plot (100 m2) on the territory of Central Chernozem Biosphere Reserve, Russia. Seasonal plowing and deficiency of fresh plant residues (due to weeding out) resulted in a rapid mineralization of SOM. The Corg content in the 0-20 cm topsoil under native grassland is 6-4.5 %. For the last two decades Corg content under bare fallow has stabilized on the 2.6% level and is therefore assumed to represent stable SOM pool. However excellent aggregate waterstability of chernozem is completely lost under bare fallow. Therefore the aim of our study is to reveal the role of different SOM pools spatial and functional organization in aggregate waterstability formation. Bulk soil samples were collected from 2 m grassland profile and 1.5 m bare fallow profile with 10 cm interval and simultaneous measurements of soil field density and moisture. Following samples were analysed: bulk samples, dry and wet-sieving aggregates, undisturbed and pulverized aggregates, granule-densimetric fractions obtained by sedimentation of bulk samples (clay 5 mkm) with following densimetric fractionation in bromoform (light ? 2.4 g/cm3), and above mentioned samples after removal of SOM by hydrogen peroxide. Isolation of aggregates and granule-densimetric fractionation were carried out for bulk soils at 0-20, 40-50 and 80-90 cm depth. We use elemental analysis (C, H, N), size exclusion and hydrophobic interaction chromatography of humic substances (HS), laser diffraction particle size analysis, specific surface area (SSA) measurements by nitrogen adsorption and micromorphological examination of thin sections. Detailed characteristics obtained for aggregates and granule-densimetric fractions from a typical chernozem soil under native grassland and under 60

  6. Reforesting "bare hills" in Vietnam: social and environmental consequences of the 5 million hectare reforestation program.

    PubMed

    McElwee, Pamela

    2009-09-01

    In recent years, forestry has been strongly promoted by the government of the Socialist Republic of Vietnam through large-scale projects to rehabilitate and reforest millions of hectares of land. One project to reforest 5 million hectares has received hundreds of millions of US dollars for implementation. Yet based on a case study in one area of northern Vietnam, this project appears to have had a number of unforeseen consequences. Large areas of land classified as "bare hills" have been targeted for reforestation, despite the fact that these lands already harbor a number of species that were used by local communities. The bare hills were especially economically important to poor households and to women who collected a variety of nontimber forest products there. Because the reforestation project focused most efforts on establishing new plantations rather than supporting natural regeneration, diverse sources of non-timber forest products were being replaced with monocrop exotic tree plantations. A strong inequity in the allocation of private lands for reforestation has characterized the regreening projects to date, and this may have continuing unwelcome social, environmental, and economic impacts into the future, particularly for the poor.

  7. Matching the BtA line to the bare-AGS (Part 1)

    SciTech Connect

    Tsoupas,N.; Glenn, J. W.; Huan, H.; MacKay, W. W.; Raparia, D.; Zeno, K.

    2008-11-01

    The Booster to AGS (BtA) transfer line [Ref for BtA line] transports the beam bunches from the AGS-Booster to the AGS synchrotron, and also matches the beam parameters ({beta}{sub x,y}, {alpha}{sub x,y}) and dispersion functions ({eta}{sub x,y}, {eta}{prime}{sub x,y}) of the transported beam to the corresponding quantities of the circulating beam in AGS, at the AGS injection point. In this technical note we describe in details, the calculations of the matching procedure of the BtA line to the bare-AGS, and provide magnet settings for the MAD-model of the BtA transfer line which is 'matched' to the bare-AGS. In a separate but more concise technical note (Part II) we will present results on the beam optics of the BtA beam line which is 'matched' to the AGS with two helical snakes.

  8. Photo-physical properties enhancement of bare and core-shell quantum dots

    SciTech Connect

    Mumin, Md Abdul Akhter, Kazi Farida Charpentier, Paul A.

    2014-03-31

    Semiconductor nanocrystals (NCs) (also known as quantum dots, QDs) have attracted immense attention for their size-tunable optical properties that makes them impressive candidates for solar cells, light emitting devices, lasers, as well as biomedical imaging. However monodispersity, high and consistent photoluminescence, photostability, and biocompatibility are still major challenges. This work focuses on optimizing the photophysical properties and biocompatibility of QDs by forming core-shell nanostructures and their encapsulation by a carrier. Highly luminescent CdS and CdS-ZnS core-shell QDs with 5 nm sizes were synthesized using a facile approach based on pyrolysis of the single molecule precursors. After capping the CdS QDs with a thin layer of ZnS to reduce toxicity, the photoluminescence and photostability of the core-shell QDs was significantly enhanced. To make both the bare and core/shell structure QDs more resistant against photochemical reactions, a mesoporous silica layer was grown on the QDs through a reverse microemulsion technique based on hydrophobic interaction. This encapsulation enhanced the quantum yield and photostability compared to the bare QDs by providing much stronger resistance to oxidation and Oswald ripening of QDs. Encapsulation also improved biocompatibility of QDs that was evaluated with human umbilical vein endothelial cell lines (HUVEC)

  9. Inversion of Electromagnetic Models for Bare Soil Parameter Estimation from Multifrequency Polarimetric SAR Data

    PubMed Central

    Pierdicca, Nazzareno; Castracane, Paolo; Pulvirenti, Luca

    2008-01-01

    The potentiality of polarimetric SAR data for the estimation of bare soil geophysical parameters (i.e., roughness and soil moisture) is investigated in this work. For this purpose, two forward models available in the literature, able to simulate the measurements of a multifrequency radar polarimeter, have been implemented for use within an inversion scheme. A multiplicative noise has been considered in the multidimensional space of the elements of the polarimetric Covariance Matrix, by adopting a complex Wishart distribution to account for speckle effects. An additive error has been also introduced on the simulated measurements to account for calibration and model errors. Maximum a Posteriori Probability and Minimum Variance criteria have been considered to perform the inversion. As for the algorithms to implement the criteria, simple optimization/integration procedures have been used. A Neural Network approach has been adopted as well. A correlation between the roughness parameters has been also supposed in the simulation as a priori information, to evaluate its effect on the estimation accuracy. The methods have been tested on simulated data to compare their performances as function of number of looks, incidence angles and frequency bands, thus identifying the best radar configuration in terms of estimation accuracy. Polarimetric measurements acquired during MAC Europe and SIR-C campaigns, over selected bare soil fields, have been also used as validation data. PMID:27873982

  10. Optical properties of plasmon-resonant bare and silica-coated nanostars used for cell imaging

    NASA Astrophysics Data System (ADS)

    Bibikova, Olga; Popov, Alexey; Bykov, Alexander; Prilepskii, Artur; Kinnunen, Matti; Kordas, Krisztian; Bogatyrev, Vladimir; Khlebtsov, Nikolai; Vainio, Seppo; Tuchin, Valery

    2015-07-01

    We synthesized and characterized gold nanostars and their silica-coated derivatives with 7- to 50-nm shell thicknesses as contrast agents for optical imaging. The scattering and absorption coefficients of the nanoparticles (NPs) were estimated by means of collimated transmittance and diffuse reflectance/transmittance analyses. The contrasting properties of the nanostructures were studied in optical coherence tomography glass capillary imaging. The silica-coated nanostars with the thickest shell have higher scattering ability in comparison with bare nanostars. Viability assays confirmed weak in vitro toxicity of nanostructures at up to ˜200-μg/mL concentrations. We showed real-time visualization of nanostars in both agarose and cultured cells by analyzing the backscattering signal using a conventional laser confocal microscope. The signal intensity detected from the silica-coated NPs was almost 1.5 times higher in comparison with bare nanostars. To the best of our knowledge, this is the first time that conventional laser confocal microscopy was applied in combined scattering and transmitted light modes to detect the backscattered signal of gold nanostars, which is useful for direct monitoring of the uptake, translocation, and accumulation of NPs in living cells.

  11. Photo-physical properties enhancement of bare and core-shell quantum dots

    NASA Astrophysics Data System (ADS)

    Mumin, Md Abdul; Akhter, Kazi Farida; Charpentier, Paul A.

    2014-03-01

    Semiconductor nanocrystals (NCs) (also known as quantum dots, QDs) have attracted immense attention for their size-tunable optical properties that makes them impressive candidates for solar cells, light emitting devices, lasers, as well as biomedical imaging. However monodispersity, high and consistent photoluminescence, photostability, and biocompatibility are still major challenges. This work focuses on optimizing the photophysical properties and biocompatibility of QDs by forming core-shell nanostructures and their encapsulation by a carrier. Highly luminescent CdS and CdS-ZnS core-shell QDs with 5 nm sizes were synthesized using a facile approach based on pyrolysis of the single molecule precursors. After capping the CdS QDs with a thin layer of ZnS to reduce toxicity, the photoluminescence and photostability of the core-shell QDs was significantly enhanced. To make both the bare and core/shell structure QDs more resistant against photochemical reactions, a mesoporous silica layer was grown on the QDs through a reverse microemulsion technique based on hydrophobic interaction. This encapsulation enhanced the quantum yield and photostability compared to the bare QDs by providing much stronger resistance to oxidation and Oswald ripening of QDs. Encapsulation also improved biocompatibility of QDs that was evaluated with human umbilical vein endothelial cell lines (HUVEC).

  12. Second stable regime of internal kink modes excited by barely passing energetic ions in tokamak plasmas

    SciTech Connect

    He, H. D.; Zheng, G. Y.; Long, Y. X.; He, Z. X.; Jiang, H. B.; Shen, Y.; Wang, L. F.; Dong, J. Q.; Fu, G. Y.; Sheng, Z. M.

    2010-08-15

    The internal kink (fishbone) modes, driven by barely passing energetic ions (EIs), are numerically studied with the spatial distribution of the EIs taking into account. It is found that the modes with frequencies comparable to the toroidal precession frequencies are excited by resonant interaction with the EIs. Positive and negative density gradient dominating cases, corresponding to off- and near-axis depositions of neutral beam injection (NBI), respectively, are analyzed in detail. The most interesting and important feature of the modes is that there exists a second stable regime in higher {beta}{sub h} (=pressure of EIs/toroidal magnetic pressure) range, and the modes may only be excited by the barely passing EIs in a region of {beta}{sub th1}<{beta}{sub h}<{beta}{sub th2} ({beta}{sub th} is threshold or critical beta of EIs). Besides, the unstable modes require minimum density gradients and minimum radial positions of NBI deposition. The physics mechanism for the existence of the second stable regime is discussed. The results may provide a means of reducing or even preventing the loss of NBI energetic ions and increasing the heating efficiency by adjusting the pitch angle and driving the system into the second stable regime fast enough.

  13. A multi-frequency radiometric measurement of soil moisture content over bare and vegetated fields

    NASA Technical Reports Server (NTRS)

    Wang, J. R.; Schmugge, T. J.; Mcmurtrey, J. E., III; Gould, W. I.; Glazar, W. S.; Fuchs, J. E. (Principal Investigator)

    1981-01-01

    A USDA Beltsville Agricultural Research Center site was used for an experiment in which soil moisture remote sensing over bare, grass, and alfalfa fields was conducted over a three-month period using 0.6 GHz, 1.4 GHz, and 10.6 GHz Dicke-type microwave radiometers mounted on mobile towers. Ground truth soil moisture content and ambient air and sil temperatures were obtained concurrently with the radiometric measurements. Biomass of the vegetation cover was sampled about once a week. Soil density for each of the three fields was measured several times during the course of the experiment. Results of the radiometric masurements confirm the frequency dependence of moisture sensing sensitivity reduction reported earlier. Observations over the bare, wet field show that the measured brightness temperature is lowest at 5.0 GHz and highest of 0.6 GHz frequency, a result contrary to expectation based on the estimated dielectric permittivity of soil water mixtures and current radiative transfer model in that frequency range.

  14. Bone strain magnitude is correlated with bone strain rate in tetrapods: implications for models of mechanotransduction.

    PubMed

    Aiello, B R; Iriarte-Diaz, J; Blob, R W; Butcher, M T; Carrano, M T; Espinoza, N R; Main, R P; Ross, C F

    2015-07-07

    Hypotheses suggest that structural integrity of vertebrate bones is maintained by controlling bone strain magnitude via adaptive modelling in response to mechanical stimuli. Increased tissue-level strain magnitude and rate have both been identified as potent stimuli leading to increased bone formation. Mechanotransduction models hypothesize that osteocytes sense bone deformation by detecting fluid flow-induced drag in the bone's lacunar-canalicular porosity. This model suggests that the osteocyte's intracellular response depends on fluid-flow rate, a product of bone strain rate and gradient, but does not provide a mechanism for detection of strain magnitude. Such a mechanism is necessary for bone modelling to adapt to loads, because strain magnitude is an important determinant of skeletal fracture. Using strain gauge data from the limb bones of amphibians, reptiles, birds and mammals, we identified strong correlations between strain rate and magnitude across clades employing diverse locomotor styles and degrees of rhythmicity. The breadth of our sample suggests that this pattern is likely to be a common feature of tetrapod bone loading. Moreover, finding that bone strain magnitude is encoded in strain rate at the tissue level is consistent with the hypothesis that it might be encoded in fluid-flow rate at the cellular level, facilitating bone adaptation via mechanotransduction.

  15. Bone strain magnitude is correlated with bone strain rate in tetrapods: implications for models of mechanotransduction

    PubMed Central

    Aiello, B. R.; Iriarte-Diaz, J.; Blob, R. W.; Butcher, M. T.; Carrano, M. T.; Espinoza, N. R.; Main, R. P.; Ross, C. F.

    2015-01-01

    Hypotheses suggest that structural integrity of vertebrate bones is maintained by controlling bone strain magnitude via adaptive modelling in response to mechanical stimuli. Increased tissue-level strain magnitude and rate have both been identified as potent stimuli leading to increased bone formation. Mechanotransduction models hypothesize that osteocytes sense bone deformation by detecting fluid flow-induced drag in the bone's lacunar–canalicular porosity. This model suggests that the osteocyte's intracellular response depends on fluid-flow rate, a product of bone strain rate and gradient, but does not provide a mechanism for detection of strain magnitude. Such a mechanism is necessary for bone modelling to adapt to loads, because strain magnitude is an important determinant of skeletal fracture. Using strain gauge data from the limb bones of amphibians, reptiles, birds and mammals, we identified strong correlations between strain rate and magnitude across clades employing diverse locomotor styles and degrees of rhythmicity. The breadth of our sample suggests that this pattern is likely to be a common feature of tetrapod bone loading. Moreover, finding that bone strain magnitude is encoded in strain rate at the tissue level is consistent with the hypothesis that it might be encoded in fluid-flow rate at the cellular level, facilitating bone adaptation via mechanotransduction. PMID:26063842

  16. Local administration of calcitriol positively influences bone remodeling and maturation during restoration of mandibular bone defects in rats.

    PubMed

    Liu, Hongrui; Cui, Jian; Feng, Wei; Lv, Shengyu; Du, Juan; Sun, Jing; Han, Xiuchun; Wang, Zhenming; Lu, Xiong; Yimin; Oda, Kimimitsu; Amizuka, Norio; Li, Minqi

    2015-04-01

    The aim of this study was to investigate the influence of calcitriol on osteoinduction following local administration into mandibular bone defects. Calcitriol-loaded absorbable collagen membrane scaffolds were prepared using the polydopamine coating method and characterized by scanning electron microscopy. Composite scaffolds were implanted into rat mandibular bone defects in the following groups: no graft material (control), bare collagen membrane (CM group), collagen membrane bearing polydopamine coating (DOP/CM group), and collagen membrane bearing polydopamine coating absorbed with calcitriol (CAL/DOP/CM group). At 1, 2, 4 and 8weeks post-surgery, the osteogenic potential of calcitriol was examined by histological and immunohistochemical methods. Following in vivo implantation, calcitriol-loaded composite scaffolds underwent rapid degradation with pronounced replacement by new bone and induced reunion of the bone marrow cavity. Calcitriol showed strong potential in inhibiting osteoclastogenesis and promotion of osteogenic differentiation at weeks 1, and 2. Furthermore, statistical analysis revealed that the newly formed bone volume in the CAL/DOP/CM group was significantly higher than other groups at weeks 1, and 2. At weeks 4, and 8, the CAL/DOP/CM group showed more mineralized bone and uniform collagen structure. These data suggest that local administration of calcitriol is promising in promoting osteogenesis and mineralization for restoration of mandibular bone defects. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Smoking and Bone Health

    MedlinePlus

    ... supported by your browser. Home Bone Basics Lifestyle Smoking and Bone Health Publication available in: PDF (85 ... late to adopt new habits for healthy bones. Smoking and Osteoporosis Cigarette smoking was first identified as ...

  18. Menopause and Bone Loss

    MedlinePlus

    Fact Sheet & Menopause Bone Loss How are bone loss and menopause related? Throughout life your body keeps a balance between the ... lose bone faster than it can be replaced. Menopause—the time when menstrual periods end, which usually ...

  19. Calcium and bones

    MedlinePlus

    ... Your body also needs calcium (as well as phosphorus) to make healthy bones. Bones are the main ... nlm.nih.gov/pubmed/25182228 . De Paula FJA, Black DM, Rosen CJ. Osteoporosis and bone biology. In: ...

  20. Disorders of Bone Remodeling

    PubMed Central

    Feng, Xu; McDonald, Jay M.

    2013-01-01

    The skeleton provides mechanical support for stature and locomotion, protects vital organs, and controls mineral homeostasis. A healthy skeleton must be maintained by constant bone modeling to carry out these crucial functions throughout life. Bone remodeling involves the removal of old or damaged bone by osteoclasts (bone resorption) and the subsequent replacement of new bone formed by osteoblasts (bone formation). Normal bone remodeling requires a tight coupling of bone resorption to bone formation to guarantee no alteration in bone mass or quality after each remodeling cycle. However, this important physiological process can be derailed by a variety of factors, including menopause-associated hormonal changes, age-related factors, changes in physical activity, drugs, and secondary diseases, which lead to the development of various bone disorders in both women and men. We review the major diseases of bone remodeling, emphasizing our current understanding of the underlying pathophysiological mechanisms. PMID:20936937