bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mitochondrial function and apoptotic susceptibility in aging skeletal muscle
Authors: Chabi Béatrice , Ljubicic Vladimir , Menzies Keir J. , Huang Julianna H. , Saleem Ayesha , Hood David A. 
Published: October 2007

SummaryDuring aging, skeletal muscle undergoes sarcopenia, a condition characterized by a loss of muscle cell mass and alterations in contractile function. The origin of these decrements is unknown, but evidence suggests that they can be partly attributed to mitochondrial dysfunction. To characterize the nature of this dysfunction, we investigated skeletal muscle contractile properties, subsarcolemmal (SS) and intermyofibrillar (IMF) mitochondrial biogenesis and function, as well as apoptotic susceptibility in young (6 months old) and senescent (36 months old) Fischer 344 Brown Norway rats. Muscle mass and maximal force production were significantly lower in the 36‐month group, which is indicative of a sarcopenic phenotype. Furthermore, contractile activity in situ revealed greater fatigability in the 36‐month compared to the 6‐month animals. This decrement could be partially accounted for by a 30% lower mitochondrial content in fast‐twitch muscle from 36‐month animals, as well as lower protein levels of the transcriptional coactivator peroxisome proliferator‐activated receptor γ coactivator‐1α. Enzyme activities and glutamate‐induced oxygen consumption rates in isolated SS and IMF mitochondria were similar between age groups. However, mitochondrial reactive oxygen species (ROS) production during state 3 respiration was ~1.7‐fold greater in mitochondria isolated from 36‐month compared to 6‐month animals, and was accompanied by a 1.8‐fold increase in the DNA repair enzyme 8‐oxoguanine glycosylase 1 in fast‐twitch muscle. Basal rates of release of cytochrome c and endonuclease G in SS mitochondria were 3.5‐ to 7‐fold higher from senescent animals. These data suggest that the age‐related sarcopenia and muscle fatigability are associated with enhanced ROS production, increased mitochondrial apoptotic susceptibility and reduced transcriptional drive for mitochondrial biogenesis.
Remarkable longevity and stress resistance of nematode PI3K‐null mutants
Authors: Ayyadevara Srinivas , Alla Ramani , Thaden John J. , Shmookler Reis Robert J. 
Published: October 2007

SummaryThe great majority of lifespan‐augmenting mutations were discovered in the nematode Caenorhabditis elegans. In particular, genetic disruption of insulin‐like signaling extends longevity 1.5‐ to 3‐fold in the nematode, and to lesser degrees in other taxa, including fruit flies and mice. C. elegans strains bearing homozygous nonsense mutations in the age‐1 gene, which encodes the class‐I phosphatidylinositol 3‐kinase catalytic subunit (PI3KCS), produce progeny that were thought to undergo obligatory developmental arrest. We now find that, after prolonged developmental times at 15–20 °C, they mature into extremely long‐lived adults with near‐normal feeding rates and motility. They survive to a median of 145–190 days at 20 °C, with nearly 10‐fold extension of both median and maximum adult lifespan relative to N2DRM, a long‐lived wild‐type stock into which the null mutant was outcrossed. PI3K‐null adults, although a little less thermotolerant, are considerably more resistant to oxidative and electrophilic stresses than worms bearing normal or less long‐lived alleles. Their unprecedented factorial gains in survival, under both normal and toxic environments, are attributed to elimination of residual and maternally contributed PI3KCS or its products, and consequent modification of kinase signaling cascades.
PROBLEMS OF THE RADIOCARBON CALENDAR AND ITS CALIBRATION
Authors: RENFREW C. , CLARK R. M. 
Published: October 2007

ABSTRACTSBoth the growing body of literature on the tree‐ring calibration of radiocarbon dates, and the variety of statistical approaches used, make it appropriate to review the basic principles involved in the construction of a calibration curve. While its ultimate validity is in part a geophysical problem, the appropriate form for the calibration function, given a specific body of data, is a statistical question centering upon the analysis of the measurement errors involved. The relationship between the calibration function and the inverse calibration function is examined, and the shortcomings of the available published calibration curves considered in the light of this examination. It is concluded that there is no reason to doubt the general principles on which the calibration is based, but a need exists for a more critical handling of the measurement data with a statistical treatment of the errors involved. The quality of the data could itself be improved by the use of replicate samples for inter‐laboratory projects specifically designed to investigate the magnitude of measurement error.
DENDROCHRONOLOGY—A REFERENCE CURVE FOR SLOW GROWN OAKS, A.D. 1230 TO 1546
Authors: FLETCHER J. M. , TAPPER M. C. , WALKER F. S. 
Published: October 2007

ABSTRACTSDetails are given of how the widths of the annual rings of oak boards, which form the panels for certain sixteenth‐century portraits painted in south‐east England or adjacent parts of the Continent, have been matched with one another. A representative ring‐width curve based on eighteen trees has been obtained and dated by region‐to‐region bridging from the master chronology, derived at Munich, for oaks grown in central and southern Germany. The feasibility of dendrochronology for oaks of slow and regular growth in late medieval times has been established for a region which extends beyond south‐east England to Oxford on the west and to Flanders and parts of France on the east and south‐east.
THERMOLUMINESCENT AUTHENTICITY STUDIES OF UNGLAZED T‘ANG DYNASTY CERAMIC TOMB GOODS
Authors: FLEMING S. J. 
Published: October 2007

ABSTRACTSImitations of T‘ang Dynasty (a.d. 618–906) ceramics were produced at the beginning of this century casting them from original piece‐moulds. The impeccable style of these wares means they are indistinguishable from their ancient prototypes by visual inspection. Examples of such imitative material are revealed by thermoluminescent dating analysis. A brief discussion of the need for and methods of the piece‐moulding technique in its use by the T‘ang artisan is also given.
RECENTLY IDENTIFIED EGYPTIAN PIGMENTS
Authors: RIEDERER J. 
Published: October 2007

ABSTRACTSOn several bowls from Nubia (1600 b.c.) and on one canopic jar (New Kingdom) huntite, a calciummagnesium‐carbonate CaCO3. 3MgCO3 was identified by means of X‐ray diffraction and infra‐red absorption techniques. Vases from the Amarna period (1370 b.c.) are decorated with a blue paint, which proved to be cobalt‐blue. Copper chloride atacamite was used on limestone reliefs from Thebes‐West but the green frit chrysocolla occurs more frequently on Egyptian objects as is mentioned in literature.
An inexpensive stereo‐image capture tool for motion study
Authors: Chong Albert K. 
Published: October 2007

AbstractThis paper discusses the evaluation of a video stereo‐image capture tool for photogrammetric applications. The ‘‘NuView Adapter’’, a commonly available video‐image splitting device, and a digital video camera (DV) could be used to capture stereoscopic video footage for many photogrammetric applications in which low‐cost near‐simultaneous stereo‐images are required for 3D viewing or for 3D spatial data capture. Relevant photogrammetric applications might include: aerial surveillance, human/animal motion study (tracking), bank/security surveillance and precise 3D animation. The device permits two distinct views (left and right perspective views) to enter a single lens DV. A single convergence control in the device allows the user to obtain a stereo view of near and far objects. The system is easy to operate and the stereo‐images give a good visual 3D effect. Research was carried out to determine the quality of the stereo‐image for 3D measurement. The investigation involved: (1) the calibration of a customised system for optimum close range photogrammetric application; and (2) a case study involving motion tracking. A semi‐automated monodigitising photogrammetric technique was used to determine the accuracy of the system. The results show that this system could achieve a spatial data accuracy of better than 13 mm at an object distance of 9 m. The horizontal and vertical accuracies are similar to those obtained by the conventional stereoscopic camera technique using a ‘‘normal case’’ configuration with 86% overlap.
Determination of optimum window size for SAR image co‐registration with decomposition of auto‐correlation
Authors: Zou Weibao , Li Zhilin , Ding Xiaoli 
Published: October 2007

AbstractInterferometric synthetic aperture radar (InSAR) is a promising recent technique for the generation of digital elevation models and/or the measurement of ground surface deformations. In InSAR data processing, the first step is the image co‐registration, achieved by using a set of tie points which are the conjugate image points on the master and slave images. Tie points are selected with the aim of finding the conjugate point automatically on the slave image for any given point on the master image, by the process known as image matching. To achieve reliable matching, a set of points within a window is used instead of a single point. The size of the window will affect the reliability of matching. Hitherto there have been no effective methods for the determination of optimum window size for this purpose. In practice, this parameter is determined by experience. In this paper, a pair of SAR images is used to test the effect of window size on the reliability of co‐registration. An optimum window size is selected on the basis of the experimental results. The determination of optimum window size for tie point matching is then examined theoretically, leading to a proposal for an automated method based on the auto‐correlation of the SAR images, which reflects the similarity between image pixels. The auto‐correlation function is decomposed into waves of various frequencies by a wavelet transform. By a combined analysis of the variations of wave amplitudes with frequency, the optimum window size for tie point matching can be determined. A procedure based on the use of Daubechies wavelet db1 is proposed in detail. An optimum window size could be determined in this way for any pair of SAR images.
Black Loyalists and Black Slaves in Maritime Canada
Authors: Whitfield Harvey Amani 
Published: October 2007

AbstractWe know a great deal about the Black Loyalists who achieved freedom during the Revolutionary War, settled in Maritime Canada, and those who eventually migrated to the coast of West Africa. However, what about black people who were slaves in the American colonies and remained slaves after migrating to Maritime Canada with their masters? This article examines the historiography of the Black Loyalists in Maritime Canada and attempts to address the experience of those who remained slaves. Indeed, to have a broader understanding of transnational black migration to Canada historians must look beyond the paradigm of from slavery in America to freedom in Canada and consider the experience of those who remained slaves.
Oil and the Origins of the Great War
Authors: Engdahl F. William 
Published: October 2007

AbstractThis article looks at the strategic if little‐known role of oil and construction of the Berlin to Baghdad railway link between the German Reich and the Persian Gulf through what is today Iraq, in igniting an economic, military, and diplomatic confrontation in Europe in the late nineteenth and early twentieth centuries, and how it ultimately contributed to the move to war in 1914. This article will set down the background to this contentious issue, and analyze the various interpretations that authors have set down in the past. It will argue that despite appearances, the British Empire was in decline after about 1873 while the new German economic colossus presented an entirely new challenge to British hegemony. To secure future domination of the seas, after 1882 leading British circles around Admiral Fischer and Winston Churchill pushed through the conversion of the Royal Navy from coal to oil. The article goes into how the Berlin‐Baghdad presented an unacceptable strategic threat to that vital strategy. The various phases in the buildup to the Great War will be examined, along with the role of oil within this broad framework. Finally, the author will posit his own conclusions to this debate.
Microtensile Bond Strength of Different Components of Core Veneered All‐Ceramic Restorations. Part 3: Double Veneer Technique
Authors: Aboushelib Moustafa N. , Kleverlaan Cornelis J. , Feilzer Albert J. 
Published: October 2007

Abstract Purpose: The bond strength of zirconia veneer has been considered a weak link in the layered all‐ceramic restoration. In a previous study, this bond was improved using a new category of veneering ceramics adopting the pressing technique; however, the resulting esthetic quality lacked the individual characterization built using the layering technique. The aim of this work was to evaluate the effect of combining both press‐on and layering veneer ceramics in one restoration on the bond strength with zirconia frameworks. Materials and Methods: Zirconia discs (19.4 mm in diameter, 3‐mm thick) were veneered with 3‐mm thick press‐on veneer ceramic or veneered with 1‐mm thick press‐on veneer ceramic and an additional 2‐mm thick of layering veneer ceramic. Two commercial layering veneer ceramics were tested. The specimens were sectioned into microbars, and the zirconia veneer microtensile bond strength (MTBS) was measured in a universal testing machine. Scanning electron microscopy (SEM) was used to examine core veneer interface quality and to assess failure type. Energy dispersive X‐ray microanalysis (EDAX) was used to analyze the chemical structure of the tested veneer ceramics, which may affect the structural integrity of the double veneered restoration. One‐way analysis of variance and Tukey HSD post hoc tests were selected to analyze the data (p < 0.05 was significant). Results: The MTBS of zirconia and press‐on ceramic (34.4 ± 2.9 MPa) was not affected by the addition of a second layer of either veneer ceramic. SEM analysis revealed defect‐free zirconia press‐on veneer interface, while the interface between the press‐on and the layering veneer ceramics demonstrated a different crystal structure and glass matrix, which did not affect wetting and contact between the two materials. EDAX analysis revealed differences, which account for the observed structural differences, in the chemical composition between the tested veneers. Conclusion: The double veneer technique combines the high bond strength and superior interface quality achieved using press‐on ceramics with the superior esthetics and individual characterization obtained using layering ceramics. The technique promises superior function and performance of the double veneered restoration.
Prosthodontic Management of Sulcoplasty and Sialodochoplasty with a Conforming Surgical Stent
Authors: Berg Robert W. , Goldman Barry M. , Kurtz Kenneth , Schweitzer Kenneth , Kraut Richard A. 
Published: October 2007

AbstractThis clinical report describes the management of chronic, proliferative inflammatory epithelial and fibrous hyperplasia following loss of a mandibular implant‐retained prosthesis. A classic surgical technique was used. The patient was referred to the oral surgeon for sialodochoplasty and sulcoplasty. With a combination of surgery and prosthodontic management with a conforming surgical stent, a satisfactory denture foundation was created, allowing for fabrication of an implant‐retained definitive prosthesis.
A Survey of Deans: Trends, Challenges, and Mentoring in Prosthodontics. Part 2
Authors: Wright Robert F. , Dunlop Ryan A. , Kim Frances M. , Weber Hans Peter , Donoff R. Bruce 
Published: October 2007

Abstract Purpose: This study consists of two parts. Part 1, a survey of program directors, was conducted to examine current trends in advanced education in prosthodontics in the United States. Part 2 reports on the findings of a survey distributed to the deans of US dental schools to evaluate their observations of trends in prosthodontic education. Materials and Methods: A national, electronic survey of 55 dental school deans was distributed by e‐mail to evaluate an interest in specialty training, an interest in specialization in prosthodontics, faculty shortages, programs to address faculty shortages, predoctoral curriculum in prosthodontics, opinions regarding dental specialties, and the administrative position of prosthodontics within the schools. Results: Of the 55 deans, 44 deans responded, an 80% response rate. Only five deans reported a decrease in the number of students seeking specialty training after dental school. The remaining 39 deans reported a large increase, slight increase, or no change in those seeking specialty training. In 29.6% of the deans' responses, an increased interest in prosthodontics was reported, whereas 16 deans reported no change in the level of interest. One or more open faculty positions in prosthodontics existed at 29 dental schools, and 28 schools offered at least one incentive or a variety of incentives to recruit faculty. The respondents to the deans' survey revealed predoctoral student exposure to prosthodontists was high, and exposure to postgraduate prosthodontics students was low. A survey of internal school programs that might have an impact on an increased interest in prosthodontics revealed the presence of a predoctoral mentoring program for prosthodontics in 80% of the institutions. The clinical curriculum included treatment of a variety of cases, including complex cases as defined by a diagnostic classification system. The response to whether dental specialties should be combined or remain individual provided some interesting data. Only 40.9% of the deans responded that prosthodontics was a separate department. Conclusion: Dental school deans reported an increased interest in specialty training. Predoctoral student exposure to prosthodontics was high due to the nature of their clinical experience and due to the exposure to full‐time prosthodontics faculty. Many dental schools have programs, such as mentoring and new technology, which might have an impact on predoctoral students' increased interest in prosthodontics.
Optimization of Maxillary Obturator Thickness Using a Double‐Processing Technique
Authors: Oh Won‐suck , Roumanas Eleni D. 
Published: October 2007

AbstractPreservation of remaining structures is a primary goal of prosthetic rehabilitation. Continuously applied stresses on the remaining tissues from a large, heavy obturator jeopardize the health of the tissues, compromise the function of the prosthesis, and affect patient comfort. Various techniques have been described for hollowing the bulb of an obturator after processing to reduce its weight; however, access to the inner aspects of the bulb is limited, preventing adequate control of thickness of the walls. This article describes a double‐processing technique for an obturator to optimize the weight and thickness of the bulb.
Masticatory dysfunction is associated with osteoporosis in older men
Authors: Laudisio Alice , Marzetti Emanuele , Antonica Livia , Settanni Silvana , Georgakakis Ioannis , Bernabei Roberto , Franceschi Claudio , Zuccalà Giuseppe 
Published: October 2007

AbstractAim: Thirty per cent of hip fractures occur in men. Nevertheless, the determinants of osteoporosis in men are unclear. Masticatory dysfunction is associated with malnutrition, and might represent an emergent cause of osteoporosis. The aim of this study was to assess the association of bone mineral density and self‐assessed masticatory dysfunction in a general older population.Material and Methods: We assessed the association of masticatory dysfunction with standard parameters of bone mineral density (T‐score, Z‐score and the stiffness index) in all 310 subjects aged 75+ living in Tuscania (Italy).Results: Among men, self‐assessed masticatory dysfunction was associated with T‐score [β=0.86, confidence intervals (CI)=0.15–1.57; p=0.019], Z‐score (β=0.86, CI=0.16–1.56; p=0.017) and the stiffness index (β=9.12, CI=0.47–17.77; p=0.039) in linear regression modeling, after adjusting. No significant associations were observed in women.Conclusions: Masticatory dysfunction is independently associated with osteoporosis in elderly men. Evaluation of masticatory function should enter the routine assessment of older men with osteoporosis.
Language background and OSCE performance: a study of potential bias
Authors: Schoonheim‐Klein M. , Hoogstraten J. , Habets L. , Aartman I. , Van der Vleuten C. , Manogue M. , Van der Velden U. 
Published: October 2007

Aim:  To investigate whether Non‐Native dental students perceive drawbacks in their education and examination experience because of their lack of language proficiency and to test whether prolonging Objective Structured Clinical Examination (OSCE) test‐station duration improves their performance.Materials and methods:  Dental students (n = 345) completed a questionnaire about their native country, their language background and the possible drawback they perceived in dental education and examination because of their language proficiency. Students were marked as ‘native’, when they were born in the Netherlands with Dutch as native language or ‘Non‐Native’ when they were born outside the Netherlands, raised with a non‐Dutch native language, or raised bilingually. A sample of 108 students was assessed by an OSCE testing a periodontal course with nine test‐stations. Test‐station topics were: (1) history taking, (2) measuring attachment level, (3) educating patients, (4) tracing a radiograph, (5) root‐planing, (6) writing a prescription, (7) diagnostics and prognostics, (8) differential diagnostics and (9) writing a referral letter. The first five test‐stations mentioned were of 5‐min duration. The other four test‐stations were provided in two modes: either with a short (5 min) or longer (10 min) version. Every student took at random two long and two short test‐stations.Results:  In the group of 345 questionnaire responders, Non‐Native students (n = 116) perceived significantly more drawback in education and examination than Native students (n = 229) (P < 0.001). When Non‐Native students speak Dutch at home, around 38% of them reported perceived drawbacks in education, whereas when they speak their native language at home, around 60% reported perceived drawbacks in education (P = 0.005). In the periodontal OSCE (n = 108), the Native group (n = 70) had significantly higher total scores than the Non‐Native (n = 38), (P = 0.009, d = 0.53). The Non‐Native group had significantly lower mean scores in the communication station ‘educating patients’ (P = 0.034, d = 0.42). Prolonged test‐station duration from 5 to 10 min had no positive effect in all experimental test‐stations in the Native and Non‐Native group. Female students in the Native group out‐performed male in a communication test‐stations. Female students in Native and Non‐Native groups were found to be more successful in ‘tracing bone loss on radiographs’.Conclusion:  Non‐Native students perceived a drawback in dental education and examination because of their language proficiency in Dutch, which is confirmed by their actual OSCE performance. Prolonging the time for a test‐station did not improve OSCE performance of Non‐Native students. It is recommended that students with problems in language ability need additional tuition and practice.