bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical Implications of the Biomechanical Fracture Threshold
Authors: Keaveny Tony M , L Bouxsein Mary 
Published: April 2008

Abstract
Because of the dichotomous nature of a bone fracture, when Φ, the ratio of the applied impact force to the bone strength, is greater than a critical value—the biomechanical fracture threshold—fracture should occur. We sought to elucidate the conceptual implications of this biomechanical fracture threshold with application to hip fracture. We used data from the PaTH study, a 2-yr clinical trial in postmenopausal women treated with alendronate, PTH, or their combination. Outcomes included the force applied to the hip in a sideways fall as estimated from subject height and weight; femoral strength as determined by QCT-based finite element analysis; the load-to-strength ratio Φ; and total hip areal BMD from DXA. Results indicated that those with “very low” femoral strength (&lt;2000 N) invariably had load-to-strength ratio Φ values well above the theoretical biomechanical fracture threshold (Φ = 1), but those with “moderately low” femoral strength (2000–4000 N) displayed Φ values both above and below the theoretical biomechanical fracture threshold. This finding implies that the risk of a hip fracture can be high in those with only moderately low BMD because femoral strength can be low relative to fall impact forces. The observed weak correlation between areal BMD and the load-to-strength ratio Φ (r2 = 0.14) suggests that consideration of the biomechanical fracture threshold may improve fracture risk assessment, particularly for those in the osteopenic range. Regarding treatment effects, only those subjects having load-to-strength ratio Φ values within a relatively narrow “transition zone” of ±20% of the assumed biomechanical fracture threshold at baseline were predicted to change fracture status during the trial. In theory, outcomes of fracture trials may be dominated by the responses of those within the “transition zone” at baseline, and treatment benefits in terms of fracture efficacy may depend the patient's baseline status with respect to the biomechanical fracture threshold. We conclude that consideration of the theoretical implications of the biomechanical fracture threshold may lead to new insights and advances in the assessment and treatment of osteoporosis.
Functional Adaptation to Loading of a Single Bone Is Neuronally Regulated and Involves Multiple Bones
Authors: Sample Susannah J , Behan Mary , Smith Lesley , Oldenhoff William E , Markel Mark D , Kalscheur Vicki L , Hao Zhengling , Miletic Vjekoslav , Muir Peter 
Published: April 2008

Abstract
Regulation of load-induced bone formation is considered a local phenomenon controlled by osteocytes, although it has also been hypothesized that functional adaptation may be neuronally regulated. The aim of this study was to examine bone formation in multiple bones, in response to loading of a single bone, and to determine whether adaptation may be neuronally regulated. Load-induced responses in the left and right ulnas and humeri were determined after loading of the right ulna in male Sprague-Dawley rats (69 ± 16 days of age). After a single period of loading at −760-, −2000-, or −3750-μϵ initial peak strain, rats were given calcein to label new bone formation. Bone formation and bone neuropeptide concentrations were determined at 10 days. In one group, temporary neuronal blocking was achieved by perineural anesthesia of the brachial plexus with bupivicaine during loading. We found right ulna loading induces adaptive responses in other bones in both thoracic limbs compared with Sham controls and that neuronal blocking during loading abrogated bone formation in the loaded ulna and other thoracic limb bones. Skeletal adaptation was more evident in distal long bones compared with proximal long bones. We also found that the single period of loading modulated bone neuropeptide concentrations persistently for 10 days. We conclude that functional adaptation to loading of a single bone in young rapidly growing rats is neuronally regulated and involves multiple bones. Persistent changes in bone neuropeptide concentrations after a single loading period suggest that plasticity exists in the innervation of bone.
Sodium and Bone Health: Impact of Moderately High and Low Salt Intakes on Calcium Metabolism in Postmenopausal Women
Authors: Teucher Birgit , Dainty Jack R , Spinks Caroline A , Majsak-Newman Gosia , Berry David J , Hoogewerff Jurian A , Foxall Robert J , Jakobsen Jette , Cashman Kevin D , Flynn Albert , Fairweather-Tait Susan J 
Published: April 2008

Abstract
High salt intake is a well-recognized risk factor for osteoporosis because it induces calciuria, but the effects of salt on calcium metabolism and the potential impact on bone health in postmenopausal women have not been fully characterized. This study investigated adaptive mechanisms in response to changes in salt and calcium intake in postmenopausal women. Eleven women completed a randomized cross-over trial consisting of four successive 5-wk periods of controlled dietary intervention, each separated by a minimum 4-wk washout. Moderately low and high calcium (518 versus 1284 mg) and salt (3.9 versus 11.2 g) diets, reflecting lower and upper intakes in postmenopausal women consuming a Western-style diet, were provided. Stable isotope labeling techniques were used to measure calcium absorption and excretion, compartmental modeling was undertaken to estimate bone calcium balance, and biomarkers of bone formation and resorption were measured in blood and urine. Moderately high salt intake (11.2 g/d) elicited a significant increase in urinary calcium excretion (p = 0.0008) and significantly affected bone calcium balance with the high calcium diet (p = 0.024). Efficiency of calcium absorption was higher after a period of moderately low calcium intake (p &lt; 0.05) but was unaffected by salt intake. Salt was responsible for a significant change in bone calcium balance, from positive to negative, when consumed as part of a high calcium diet, but with a low calcium intake, the bone calcium balance was negative on both high and low salt diets.
The Influence of Cultural Background on Experiences and Beliefs about Traumatic Brain Injury and their Association with Outcome
Authors: Saltapidas Helen , Ponsford Jennie 
Published: April 2008

AbstractThe aim of the study was to compare beliefs and experiences of traumatic brain injury (TBI) in patients with TBI from the dominant English-speaking culture in Australia versus those from minority culturally and linguistically diverse (CALD) backgrounds and examine the relative influence of beliefs, acculturation, along with demographic and injury-related variables on outcome. The primary measures included the Illness Perception Questionnaire-Revised (IPQ-R), and the Craig Handicap Assessment and Reporting Technique (CHART). Participants were 70 individuals with mild to severe TBI, including 38 of English-speaking background (ESB) and 32 from CALD backgrounds. Although similar to the ESB participants in education, preinjury employment status, injury severity and experience of TBI, the CALD participants differed significantly from ESB participants on acculturation variables. CALD participants also experienced greater negative emotions and were less likely to have internal locus of control causal beliefs than ESB participants. Regression analyses indicated that describing one's value system as other than Australian, poorer understanding of TBI and greater negative emotional reactions, along with fewer years of education were associated with poorer outcomes on the CHART. Thus, in treating patients from different cultural backgrounds it is important for health professionals to understand beliefs about and responses to TBI, as they could potentially impact on coping, emotional adjustment and long-term outcome.
The Westmead Post-Traumatic Amnesia Scale for Children (WPTAS-C) Aged 4 and 5 Years Old
Authors: Rocca Antonella , Wallen Margaret , Batchelor Jennifer 
Published: April 2008

AbstractAssessment of posttraumatic amnesia (PTA) in young children remains problematic. This article details a version of the Westmead PTA Scale, which was adapted for use with children aged 4 and 5 years, and an evaluation of this scale with typically developing children. The Westmead PTA Scale for Children (WPTAS-C) comprises 2 orientation and 4 memory questions, including 2 items involving remembering pictures of familiar objects. Participants included 55 preschool and kindergarten children aged 4 and 5 years. The scale was administered for 4 consecutive days. Ninety-three per cent of the children achieved a score of 6 out 6 for the final 3 days of the 4-day test period. It is concluded that the WPTAS-C is an appropriate measure of orientation and continuous memory in 4- and 5-year-old typically developing children. Validation of the scale in clinical populations is recommended.
A Simple and Effective Laboratory Test Device for Measuring Tire-Pavement Contact Pressure
Authors: Hu Xiaodi , Sun Lijun , Hu Sheng , Walubita Lubinda F. 
Published: April 2008

Abstract
For most mechanistic response analyses of asphalt pavements, the traffic loading between the tire and the pavement is often modeled as a circular contact area with a uniform stress distribution. In reality, the tire-pavement contact pressure is hardly circular or uniformly distributed. In order to more accurately model the pavement responses under traffic loading, it is necessary to measure the actual tire-pavement contact pressure (TPCP) and then use it for pavement mechanistic response analyses. Currently there are a few devices that can be used to measure the TPCP. However, most of these existing devices have some limitations. For example one of the major disadvantages is the fact that the measured data were the pressure between the tire and a steel plate, and not between the tire and the asphalt pavement. For accurate TPCP measurements in this paper, a simple and effective static laboratory test device was developed. One of the features of this device is that the pressure sensors were inserted and suspended within the asphalt slab and the top of the sensors were kept flush with the surface at the interface with the tire. This enabled the true TPCP between the tire and the asphalt surface to be measured. Additionally, the device is relatively easy to set up and conduct the tests. Thus far, the laboratory measured TPCP results with this static test device were reasonably consistent with existing theories and assumptions about modeling the TPCP and pavement mechanistic responses.
Mensch-Roboter Interaktion in Rettungseinsätzen (Human-Robot Interaction in Rescue Operations)
Authors: Driewer Frauke , Sauer Markus , Schilling Klaus 
Published: April 2008

Zusammenfassung
In zukünftigen Rettungseinsätzen können mobile Roboter zur Unterstützung von Einsatzkräften eingesetzt werden. Trotz der großen Fortschritte im Bereich Autonomie, die in der Robotik erreicht wurden, werden Roboter den Menschen vorerst nicht komplett ersetzen können. Bevor Rettungsroboter standardmäßig als Unterstützung in Mensch-Roboter Teams eingesetzt werden können, gilt es effiziente Interaktion als eines der Hauptprobleme zu lösen. Hierbei sollen Rettungsroboter zusammen mit den Einsatzkräften vor Ort, durch einen Einsatzleiter koordiniert werden. Die gesammelten Sensordaten und andere Informationen müssen angemessen aufgearbeitet und in einer entsprechenden Benutzungs-schnittstelle visualisiert werden. Auf Basis einer Nutzeranalyse mit Feuerwehrkräften werden die Anforderungen für ein entsprechendes System erläutert. Die experimentelle Auswertung wird vorgestellt, die unterschiedlichen Erfahrungen und entsprechende Vorschläge für zu-künftige Benutzungsschnittstellen werden diskutiert.
Mensch-Computer-Interaktionsgestaltung zur Luftlagebewertung (Human-Computer Interaction Design for Air Situation Assessment)
Authors: Schmidt Ludger , Ley Daniel 
Published: April 2008

Zusammenfassung
Dieser Beitrag beschreibt die modellbasierte Gestaltung der Mensch-Computer-Interaktion an militärischen Arbeitsplätzen zur Luftlagebewertung. Die Interaktion wird zunächst allgemein anhand eines erweiterten Semiotischen Modells auf vier Ebenen (pragmatisch, semantisch, syntaktisch und physikalisch) charakterisiert. Daraus werden die entsprechenden Ges-taltungsbereiche abgeleitet und kurz beschrieben. Als exemplarische Umsetzung wird dann anhand eines Prototyps die Gestaltung einer Benutzungsschnittstelle für die Luftlagebewertung dargestellt.
Analyse von Fahrer- und Pilotenfehlern mit integrierten Mensch-Maschine-Umgebung Modellen (Analysis of Driver and Pilot Errors Using Integrated Man-Machine-Environment Models)
Authors: Lüdtke Andreas 
Published: April 2008

Zusammenfassung
In diesem Beitrag wird ein Ansatz zur Analyse sicherheitskritischer Assistenzsysteme im Flugzeug oder Automobil unter Verwendung integrierter Mensch-Maschine-Umgebung Modellen vorgestellt. Dabei wird ein kognitives Modell zur ablauffähigen Simulation des menschlichen Verhaltens aufgebaut, um eine frühe Bewertung von Assistenzentwürfen aus Sicht der späteren Anwender zu ermöglichen. Es wird gezeigt, wie kognitive Modelle gezielt auf zu analysierende Phänomene des menschlichen Verhaltens abgestimmt werden können. Am Beispiel der Analyse „gelernter Sorglosigkeit” werden die Prinzipien des Ansatzes verdeutlicht.
Eye-Tracking zur Unterstützung der Verdachtsmarkierung in der Videoüberwachung (Eye Tracking for the Assistance of Suspicion Indications in Video Based Surveillance)
Authors: Fischer Peter , Geisler Jürgen 
Published: April 2008

Zusammenfassung
„Online”-Bildauswerter in der polizeilichen und militärischen Aufklärung müssen neben Ihrer Haupttätigkeit der Auswertung des Videodatenstroms ebenfalls die Aufgabe des Markierens auffälliger Objekte zur Kommunikation an den „Offline”-Bildauswerter erfüllen. Eine textliche oder sprachliche Form ist hierbei unbefriedigend, da diese beide Auswerter in nicht unerheblichem Maße kognitiv belastet. Hier bietet sich als Alternative der Einsatz von Blickbewegungsregistrierung zur Minimierung dieser kognitiven Zusatzbelastung an. Die Markierung könnte durch den „Online”-Bildauswerter mittels Tastendruck geschehen. Ein Rahmen wird um die aktuelle Blickposition gezeichnet und das so entstandene Bild an den „Offline”-Bildauswerter weitergeleitet. Die Blickdaten bilden hier also den Kommunikationskanal für die wichtige Markierungsinformation. Dieser Beitrag beschreibt eine Versuchsumgebung zur Ermittlung der örtlichen und zeitlichen Präzision eines solchen Ansatzes und stellt bezüglich letzterer ausgehend vom „Model Human Processor” (Card, Moran und Newell 1983) eine Hypothese zu deren Vorhersage auf.
Modellierung sicherheitskritischer Kommunikation in Aufgabenmodellen (Modelling Safety-Critical Communication within Task Models)
Authors: Mistrzyk Tomasz , Szwillus Gerd 
Published: April 2008

Zusammenfassung
Die Spezifikation von Aufgabenmodellen für sozio-technische Systeme bekommt besondere Bedeutung, wenn es um sicherheitskritische Systeme geht. Probleme bei der Kommunikation innerhalb derartiger Systeme wurden inzwischen als Hauptursache für das Entstehen sowohl kritischer Situationen als auch von Unfällen erkannt. In einem Forschungsprojekt haben wir eine Aufgabenmodellierungsumgebung entwickelt, die die speziellen Bedürfnisse derartiger Systeme ausdrück-lich berücksichtigt. Das Modell erlaubt die Spezifikation von Risikofaktoren, Barrieren und insbesondere auch des Informationsflusses zwischen einzelnen Aufgaben. In diesem Artikel stellen wir den Ansatz vor, mit spezieller Betonung der Kommunikationsvorgänge in Aufgabenmodellen. Wir zeigen auf, wie Kommunikation als orthogonale Struktur explizit formuliert werden kann, so dass deutlich wird, wie Kommunikation zur erfolgreichen Durchführung kooperativer Aufgaben beiträgt.
Gallium substitution in the alumosilicate framework: synthesis and structural studies of hydro sodalites
Authors: Murshed M. Mangir , Gesing Thorsten M. 
Published: April 2008

Abstract
A series of hydro sodalites of composition Na6[Al1−yGaySiO4]6(H2O)8 (0 ≤ y ≤ 1) have been prepared from Na6+x[Al1−yGaySiO4]6(OH · H2O)x(H2O)8−4x sodalites by NaOH/H2O exchange methods carried out in acidic aqueous media. One of the end members (y = 1) Na6[GaSiO4]6(H2O)8 is obtained from Na8[GaSiO4]6I2 by a hydrothermal transformation process. The polycrystalline samples are characterized by Rietveld refinements using X-ray powder diffraction data. The cell parameter fluctuates slightly from the [AlSiO4]6 to the [GaSiO4]6 framework with an average value of 884.8 pm. The occurrence of an almost constant cell parameter has been explained as a combined effect of hydrogen bonding between the oxygen atoms of the entrapped water (or the occluded [Na3□(H2O)4]3+ complex in the β-cage as a whole), and the framework together with six-ring window deformation. During XRD refinements both aluminium and gallium atoms have been converged to a single crystallographic site. The Al/Ga—O bond distance therefore indicates the mean of Al—O and Ga—O distances, which increases with increasing gallium content in the framework. However, the Si—O distance remains almost constant at 162.9 pm at any Ga/Al ratio. The coupled twisting of the (Al,Ga)O4 and SiO4 tetrahedra confirms the increase of tilt angles and decrease of six-ring pore dimension upon aluminium replacement by gallium in the framework. Results of 1H and 29Si MAS NMR as well as FTIR spectroscopy are also discussed in terms of successive gallium incorporation in the alumosilicate hydro sodalite frameworks.
Metalophosphates with mixed-polyhedral framework structures: syntheses and characterization
Authors: Bieniok Anna , Brendel Uwe , Lottermoser Werner , Amthauer Georg 
Published: April 2008

Abstract
Three new microporous compounds with octahedral-pentahedral-tetrahedral framework structures (so called OPT materials) with metalophosphate composition were prepared under solvothermal conditions and characterized by X-ray diffraction and Mössbauer spectroscopy. Ironalumino- and irongallophosphates are violet and brown-violet crystals with NH4[Fe1.15Al1.85P3O12](H2O)2 and NH4[Fe1.05Ga1.95P3O12] (H2O)2 composition. Nickelgallophosphate NH4[Ni1.0Ga2.0P3O12](H2O)2 forms light yellow lozenges. All products have isotype crystal structures in space group C2/c. The framework structures are built of corner- and edge-sharing distorted octahedra, trigonal bipyramids and phosphate tetrahedra. Iron occurs in two different valence states and occupies different polyhedra types in the structures, confirmed by Mössbauer spectroscopy. The compounds have three-dimensional channel systems which are filled by ammonium groups and water molecules, forming a strong hydrogen bonding system. Upon heating, the frameworks collapse during deammonization at temperatures below 573 K. A deformation analysis of the different coordination polyhedra in comparable compounds was performed and the structural relationship to a similar ammonium gallophosphate is discussed.
The high pressure crystal structures of tin sulphate: a case study for maximal information recovery from 2D powder diffraction data
Authors: Hinrichsen Bernd , Dinnebier Robert E. , Liu Haozhe , Jansen Martin 
Published: April 2008

Abstract
Our recently proposed method for automatic detection, calibration and evaluation of Debye–Scherrer ellipses using pattern recognition techniques and advanced signal filtering was applied to 2D powder diffraction data of tin sulphate in dependence on pressure. Three phase transitions towards higher pressure could be identified, and their respective crystal structures have been determined. The high pressure behaviour of the stereoactive lone pair of Sn2+ was investigated. At ambient conditions, SnSO4 crystallizes in a strongly distorted Barite structure type in space group Pnma (phase I). In the pressure range between P = 0.15 and P = 0.2 GPa, it exhibits a displacive second order phase transition into a structure with space group P1121/a (phase II at P = 0.2 GPa: a = 8.7022(9) Å, b = 5.3393(5) Å, c = 7.0511(6) Å, γ = 89.90(1)°). A second displacive phase transition occurs between P = 4.40 and P = 5.07 GPa into another structure with space group P-1 (phase III at P = 13.5 GPa: a = 8.067(3) Å, b = 5.141(2) Å, c = 6.609(2) Å, α = 90.56(3)°, β = 90.65(2)°, γ = 89.46(2)°). A third displacive phase transition towards another crystal structure in space group P-1 occurs between P = 13.6 and P = 15.3 GPa (phase IV at P = 20.5 GPa: a = 7.889(5) Å, b = 5.028(3) Å, c = 6.462(3) Å, α = 90.99(3)°, β = 91.01(3)°, γ = 89.89(4)°).). A non-linear compression behaviour over the entire pressure range is observed, which can be described by three Vinet relations in the ranges from P = 0.21 to 4.4 GPa, from P = 5.07 to 13.55 GPa and from P = 15.26 to 20.5 GPa. The extrapolated bulk moduli of the high-pressure phases were determined to K
0 = 48(1) GPa for phase II, K
0 = 56(2) GPa for phase III, and K
0 = 51(13) GPa for phase IV. The crystal structures of all phases are refined against X-ray powder diffraction data measured at several pressures between 0.15 and 20.5 GPa. The structural phase transitions of SnSO4 are mainly characterized by a reorientation of the SO4 tetrahedra, in order to optimize crystal packing. With increasing pressure, the lone pair which is localized at Sn2+ increasingly adopts pure s-character.
Compounds of glycine with halogen or metal halogenides: review and comparison
Authors: Fleck Michel 
Published: April 2008

Abstract
The large family of glycine halogenides and metal halogenides encompasses a high variety of different crystal structures. The role of the glycine molecule as a structural unit as a mono-, bi- or tridentate ligand, of the halogenide ions as well as the composition and condensation of the cationic polyhedra is discussed. With respect to the connectivity of the building units, five different structure families of glycine halogenides and glycine-metal halogenides can be distinguished. Parameters such as symmetry, ionic radii, electronegativity of cation and anion and their difference, charge, coordination number, hydration states, stoichiometric ratios and connectivity were weighed against each other in order to see if any correlations exist. The data suggest that cations with high electronegativities seem to promote formation of structures with a low grade of connectivity, i.e., isolated units, and vice versa.
What is a co-crystal?
Authors: Zukerman-Schpector Julio , Tiekink Edward R. T. 
Published: April 2008

Abstract
What might very well be classified as a revolution in chemical crystallography is the emergence of crystal engineering as a discipline and the pivotal role X-ray crystallography plays in this [1]. Although dating back to the 1950's, the field has exploded in the last decade or so, and now is at the forefront of contemporary chemical and cognisant research. One of the areas in crystal engineering of greatest potential impact relates to the pharmaceutical industry – drug formulation and intellectual property – where issues relating to crystallisation, polymorphism, etc. are paramount [2]. A focus of these crystal engineering studies relates to the preparation of multi-component crystals, often referred to as co-crystals, where, for example utilizing hydrogen bonding synthons, active pharmaceutical ingredients are co-crystallised with other molecules [2]. The motivation for such studies is to improve stability (e.g. shelf-life), bioavailability (e.g. solubility), etc. [3].