858 resultados para Forensic Dentistry
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Enterprises, both public and private, have rapidly commenced using the benefits of enterprise resource planning (ERP) combined with business analytics and “open data sets” which are often outside the control of the enterprise to gain further efficiencies, build new service operations and increase business activity. In many cases, these business activities are based around relevant software systems hosted in a “cloud computing” environment. “Garbage in, garbage out”, or “GIGO”, is a term long used to describe problems in unqualified dependency on information systems, dating from the 1960s. However, a more pertinent variation arose sometime later, namely “garbage in, gospel out” signifying that with large scale information systems, such as ERP and usage of open datasets in a cloud environment, the ability to verify the authenticity of those data sets used may be almost impossible, resulting in dependence upon questionable results. Illicit data set “impersonation” becomes a reality. At the same time the ability to audit such results may be an important requirement, particularly in the public sector. This paper discusses the need for enhancement of identity, reliability, authenticity and audit services, including naming and addressing services, in this emerging environment and analyses some current technologies that are offered and which may be appropriate. However, severe limitations to addressing these requirements have been identified and the paper proposes further research work in the area.
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Database watermarking has received significant research attention in the current decade. Although, almost all watermarking models have been either irreversible (the original relation cannot be restored from the watermarked relation) and/or non-blind (requiring original relation to detect the watermark in watermarked relation). This model has several disadvantages over reversible and blind watermarking (requiring only watermarked relation and secret key from which the watermark is detected and original relation is restored) including inability to identify rightful owner in case of successful secondary watermarking, inability to revert the relation to original data set (required in high precision industries) and requirement to store unmarked relation at a secure secondary storage. To overcome these problems, we propose a watermarking scheme that is reversible as well as blind. We utilize difference expansion on integers to achieve reversibility. The major advantages provided by our scheme are reversibility to high quality original data set, rightful owner identification, resistance against secondary watermarking attacks, and no need to store original database at a secure secondary storage.
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Digital forensics concerns the analysis of electronic artifacts to reconstruct events such as cyber crimes. This research produced a framework to support forensic analyses by identifying associations in digital evidence using metadata. It showed that metadata based associations can help uncover the inherent relationships between heterogeneous digital artifacts thereby aiding reconstruction of past events by identifying artifact dependencies and time sequencing. It also showed that metadata association based analysis is amenable to automation by virtue of the ubiquitous nature of metadata across forensic disk images, files, system and application logs and network packet captures. The results prove that metadata based associations can be used to extract meaningful relationships between digital artifacts, thus potentially benefiting real-life forensics investigations.
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We present a proof of concept for a novel nanosensor for the detection of ultra-trace amounts of bio-active molecules in complex matrices. The nanosensor is comprised of gold nanoparticles with an ultra-thin silica shell and antibody surface attachment, which allows for the immobilization and direct detection of bio-active molecules by surface enhanced Raman spectroscopy (SERS) without requiring a Raman label. The ultra-thin passive layer (~1.3 nm thickness) prevents competing molecules from binding non-selectively to the gold surface without compromising the signal enhancement. The antibodies attached on the surface of the nanoparticles selectively bind to the target molecule with high affinity. The interaction between the nanosensor and the target analyte result in conformational rearrangements of the antibody binding sites, leading to significant changes in the surface enhanced Raman spectra of the nanoparticles when compared to the spectra of the un-reacted nanoparticles. Nanosensors of this design targeting the bio-active compounds erythropoietin and caffeine were able to detect ultra-trace amounts the analyte to the lower quantification limits of 3.5×10−13 M and 1×10−9 M, respectively.
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The objectives of this study were to describe root caries patterns of Chinese adults and to analyze the effect of selected demographic and socioeconomic factors on these patterns. A total sample of 1080 residents aged 35-44-years-old and 1080 residents aged 65-74-years-old from three urban and three rural survey sites in Hubei Province participated in both an oral health interview and a clinical oral health examination. Root surface caries prevalence rates were 13.1% in the middle-aged group and 43.9% in the elderly group. The mean number of teeth affected by caries in the middle-aged group was reported at 0.21 and 1.0 in the elderly group. Mean Root Caries Index (RCI) scores of the middle-aged were reported at 6.29 and elderly subjects were reported at 11.95. Elderly people living in rural areas reported a higher RCI score (13.24) than those living in urban areas (10.70). A significantly higher frequency of root surface caries was observed in elderly participants (P < 0.001, OR = 3.80) and ethnic minorities (P < 0.001, OR = 1.93). In addition, smokers, nontea drinkers, and those with an annual household income of 10,000 yuan or less tended to have higher caries prevalence. RCI figures for the different tooth types ranged from 1% to 16%, indicating a wide variation in attack rates. In conclusion, our study suggests that root surface caries occurrence is high among the Chinese adult population, especially older adults. With an increasing number of retained teeth in both middle-aged and elderly people, root caries is a growing disease in the People's Republic of China which deserves more attention in future research.
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Hydroxyapatite (HA) coatings have numerous applications in orthopedics and dentistry, owing to their excellent ability to promote stronger implant fixation and faster bone tissue ingrowth and remodeling. Thermal plasma spray and other plasma-assisted techniques have recently been used to synthesize various calcium phosphate-based bioceramics. Despite notable recent achievements in the desired stoichiometry, phase composition, mechanical, structural, and bio-compatible properties, it is rather difficult to combine all of the above features in a single coating. For example, many existing plasma-sprayed HA coatings fall short in meeting the requirements of grain size and crystallinity, and as such are subject to enhanced resorption in body fluid. On the other hand, relatively poor interfacial bonding and stability is an obstacle to the application of the HA coatings in high load bearing Ti6Al4V knee joint implants. Here, we report on an alternative: a plasma-assisted, concurrent, sputtering deposition technique for high performance biocompatible HA coatings on Ti6Al4V implant alloy. The plasma-assisted RF magnetron co-sputtering deposition method allows one to simultaneously achieve most of the desired attributes of the biomimetic material and overcome the aforementioned problems. This article details the film synthesis process specifications, extensive analytical characterization of the material's properties, mechanical testing, simulated body fluid assessments, biocompatibility and cytocompatibility of the HA-coated Ti6Al4V orthopedic alloy. The means of optimization of the plasma and deposition process parameters to achieve the desired attributes and performance of the HA coating, as well as future challenges in clinical applications are also discussed.
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Background In Australia, the profession of pharmacy has undergone many changes to adapt to the needs of the community. In recent years, concerns have been raised with evidence emerging of workforce saturation in traditional pharmacy practice sectors. It is not known how current final year pharmacy students’ perceive the different pharmacy career paths in this changing environment. Hence investigating students’ current experiences with their pharmacy course, interaction with the profession and developing an understanding of their career intentions would be an important step, as these students would make up a large proportion of future pharmacy workforce Objective The objective of this study was thus to investigate final year students’ career perspectives and the reasons for choosing pharmacy, satisfaction with this choice of pharmacy as a tertiary course and a possible future career, factors affecting satisfaction and intention of future career paths. Methods A quantitative cross sectional survey of final year students from 3 Australian universities followed by a qualitative semi-structured interview of a convenience sample of final year students from the University of Sydney. Results ‘Interest in health and medicine’ was the most important reason for choosing pharmacy (n=238). The majority of students were ‘somewhat satisfied’ with the choice of pharmacy (35.7%) as a course and possible future career. Positive associations were found between satisfaction and reasons for joining pharmacy such as ‘felt pharmacy is a good profession’ (p=0.003) while negative associations included ‘joined pharmacy as a gateway to medicine or dentistry’ (p=0.001). Quantitate and qualitative results showed the most frequent perception of community pharmacy was ‘changing’ while hospital and pharmaceutical industry was described as ‘competitive’ and ‘research’ respectively. The highest career intention was community followed by hospital pharmacy. Conclusion Complex factors including university experiences are involved in shaping students’ satisfaction and perception of career. This may relate to challenges in the community pharmacy sector, job opportunities in hospital and limited understanding of the pharmaceutical industry. The results offer insight for the profession in terms of entry into various roles and also to pharmacy educators for their roles in shaping curricula and placement experiences that attract future graduates to defined career pathways in pharmacy.
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Utilising computed tomography scans to allow a virtual analysis of three-dimensional reconstructions of the femur, this project confirms that the traditional 1952 Trotter and Gleser stature estimation equations are inapplicable for a contemporary Queensland population. Therefore, this study introduces modern stature estimation equations for femoral length and fragmentary femoral remains using Bayesian statistics for application in forensic anthropological casework. In addition, it was found that caution needs to be applied when comparing estimated stature to reported stature on the missing persons database due to inaccuracy in Queensland drivers' licences.
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Introduction: Many studies have indicated the poor psychological health of medical and dental students. However, few studies have assessed the longitudinal trajectory of that psychological health at different times in an academic year. Aim: To evaluate the positive and negative aspects of psychological health among preclinical medical and dental students in Saudi Arabia prospectively. Methods: A total of 317 preclinical medical and dental students were recruited for a longitudinal study design from second and third-year students at Umm Al-Qura University in the 2012-2013 academic year. The students were assessed at the middle of the first term and followed up after 3-monthes at the beginning of the second term. Questionnaires included assessment of depression, anxiety, stress, self-efficacy, and satisfaction with life. Results: Depression, anxiety, stress, and satisfaction with life were improved significantly at the beginning of the second term, whereas self-efficacy did not change significantly. The medical, female, and third-year student subgroups had the most significant changes. Depression and stress were significantly changed at the beginning of the second term in most demographic subgroups. Conclusion: Preclinical medical and dental students have different psychological health levels at different times of the same academic year. It is recommended to consider time of data collection when analyzing the results of such studies.
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Firstly, we would like to thank Ms. Alison Brough and her colleagues for their positive commentary on our published work [1] and their appraisal of our utility of the “off-set plane” protocol for anthropometric analysis. The standardized protocols described in our manuscript have wide applications, ranging from forensic anthropology and paleodemographic research to clinical settings such as paediatric practice and orthopaedic surgical design. We affirm that the use of geometrically based reference tools commonly found in computer aided design (CAD) programs such as Geomagic Design X® are imperative for more automated and precise measurement protocols for quantitative skeletal analysis. Therefore we stand by our recommendation of the use of software such as Amira and Geomagic Design X® in the contexts described in our manuscript...
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After attending this presentation, attendees will gain awareness of the ontogeny of cranial maturation, specifically: (1) the fusion timings of primary ossification centers in the basicranium; and (2) the temporal pattern of closure of the anterior fontanelle, to develop new population-specific age standards for medicolegal death investigation of Australian subadults. This presentation will impact the forensic science community by demonstrating the potential of a contemporary forensic subadult Computed Tomography (CT) database of cranial scans and population data, to recalibrate existing standards for age estimation and quantify growth and development of Australian children. This research welcomes a study design applicable to all countries faced with paucity in skeletal repositories. Accurate assessment of age-at-death of skeletal remains represents a key element in forensic anthropology methodology. In Australian casework, age standards derived from American reference samples are applied in light of scarcity in documented Australian skeletal collections. Currently practitioners rely on antiquated standards, such as the Scheuer and Black1 compilation for age estimation, despite implications of secular trends and population variation. Skeletal maturation standards are population specific and should not be extrapolated from one population to another, while secular changes in skeletal dimensions and accelerated maturation underscore the importance of establishing modern standards to estimate age in modern subadults. Despite CT imaging becoming the gold standard for skeletal analysis in Australia, practitioners caution the application of forensic age standards derived from macroscopic inspection to a CT medium, suggesting a need for revised methodologies. Multi-slice CT scans of subadult crania and cervical vertebrae 1 and 2 were acquired from 350 Australian individuals (males: n=193, females: n=157) aged birth to 12 years. The CT database, projected at 920 individuals upon completion (January 2014), comprises thin-slice DICOM data (resolution: 0.5/0.3mm) of patients scanned since 2010 at major Brisbane Childrens Hospitals. DICOM datasets were subject to manual segmentation, followed by the construction of multi-planar and volume rendering cranial models, for subsequent scoring. The union of primary ossification centers of the occipital bone were scored as open, partially closed or completely closed; while the fontanelles, and vertebrae were scored in accordance with two stages. Transition analysis was applied to elucidate age at transition between union states for each center, and robust age parameters established using Bayesian statistics. In comparison to reported literature, closure of the fontanelles and contiguous sutures in Australian infants occur earlier than reported, with the anterior fontanelle transitioning from open to closed at 16.7±1.1 months. The metopic suture is closed prior to 10 weeks post-partum and completely obliterated by 6 months of age, independent of sex. Utilizing reverse engineering capabilities, an alternate method for infant age estimation based on quantification of fontanelle area and non-linear regression with variance component modeling will be presented. Closure models indicate that the greatest rate of change in anterior fontanelle area occurs prior to 5 months of age. This study complements the work of Scheuer and Black1, providing more specific age intervals for union and temporal maturity of each primary ossification center of the occipital bone. For example, dominant fusion of the sutura intra-occipitalis posterior occurs before 9 months of age, followed by persistence of a hyaline cartilage tongue posterior to the foramen magnum until 2.5 years; with obliteration at 2.9±0.1 years. Recalibrated age parameters for the atlas and axis are presented, with the anterior arch of the atlas appearing at 2.9 months in females and 6.3 months in males; while dentoneural, dentocentral and neurocentral junctions of the axis transitioned from non-union to union at 2.1±0.1 years in females and 3.7±0.1 years in males. These results are an exemplar of significant sexual dimorphism in maturation (p<0.05), with girls exhibiting union earlier than boys, justifying the need for segregated sex standards for age estimation. Studies such as this are imperative for providing updated standards for Australian forensic and pediatric practice and provide an insight into skeletal development of this population. During this presentation, the utility of novel regression models for age estimation of infants will be discussed, with emphasis on three-dimensional modeling capabilities of complex structures such as fontanelles, for the development of new age estimation methods.
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Despite the prominent use of the pubic symphysis for age estimation in forensic anthropology, little has been documented regarding the quantitative morphological and micro-architectural changes of this surface. Specifically, utilising post-mortem computed tomography data from a large, contemporary Australian adult population, this study aimed to evaluate sexual dimorphism in the morphology and bone composition of the symphyseal surface; and temporal characterisation of the pubic symphysis in individuals of advancing age. The sample consisted of multi-slice computed tomography (MSCT) scans of the pubic symphysis(slice thickness: 0.5 mm, overlap: 0.1 mm) of 200 individuals of Caucasian ancestry aged 15–70 years, obtained in 2011. Surface rendering reconstruction of the symphyseal surface was conducted in OsiriX1 (v.4.1) and quantitative analyses in Rapidform XOSTM and OsteomeasureTM. Morphometric variables including inter-pubic distance, surface area, circumference, maximum height and width of the symphyseal surface and micro-architectural assessment of cortical and trabecular bone compositions were quantified using novel automated engineering software capabilities. The major results of this study are correlated with the macroscopic ossification and degeneration pattern of the symphyseal surface, demonstrating significant age-related changes in the morphometric and bone tissue variables between 15 and 70 years. Regardless of sex, the overall dimensions of the symphyseal surface increased with age, coupled with a decrease in bone mass in the trabecular and cortical bone compartments. Significant differences between the ventral, dorsal and medial cortical surfaces were observed, which may be correlated to bone formation activity dependent on muscle activity and ligamentous attachments. Our study demonstrates significant sexual dimorphism at this site, with males exhibiting greater surface dimensions than females. These baseline results provide a detailed insight into the changes in the structure of the pubic symphysis with ageing and sexually dimorphic features associated with the cortical and trabecular bone profiles.
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The solutions proposed in this thesis contribute to improve gait recognition performance in practical scenarios that further enable the adoption of gait recognition into real world security and forensic applications that require identifying humans at a distance. Pioneering work has been conducted on frontal gait recognition using depth images to allow gait to be integrated with biometric walkthrough portals. The effects of gait challenging conditions including clothing, carrying goods, and viewpoint have been explored. Enhanced approaches are proposed on segmentation, feature extraction, feature optimisation and classification elements, and state-of-the-art recognition performance has been achieved. A frontal depth gait database has been developed and made available to the research community for further investigation. Solutions are explored in 2D and 3D domains using multiple images sources, and both domain-specific and independent modality gait features are proposed.
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The repair of bone defects that result from periodontal diseases remains a clinical challenge for periodontal therapy. β-tricalcium phosphate (β-TCP) ceramics are biodegradable inorganic bone substitutes with inorganic components that are similar to those of bone. Demineralized bone matrix (DBM) is an acid-extracted organic matrix derived from bone sources that consists of the collagen and matrix proteins of bone. A few studies have documented the effects of DBM on the proliferation and osteogenic differentiation of human periodontal ligament cells (hPDLCs). The aim of the present study was to investigate the effects of inorganic and organic elements of bone on the proliferation and osteogenic differentiation of hPDLCs using three-dimensional porous β-TCP ceramics and DBM with or without osteogenic inducers. Primary hPDLCs were isolated from human periodontal ligaments. The proliferation of the hPDLCs on the scaffolds in the growth culture medium was examined using a Cell‑Counting kit‑8 (CCK-8) and scanning electron microscopy (SEM). Alkaline phosphatase (ALP) activity and the osteogenic differentiation of the hPDLCs cultured on the β-TCP ceramics and DBM were examined in both the growth culture medium and osteogenic culture medium. Specific osteogenic differentiation markers were examined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). SEM images revealed that the cells on the β-TCP were spindle-shaped and much more spread out compared with the cells on the DBM surfaces. There were no significant differences observed in cell proliferation between the β-TCP ceramics and the DBM scaffolds. Compared with the cells that were cultured on β-TCP ceramics, the ALP activity, as well as the Runx2 and osteocalcin (OCN) mRNA levels in the hPDLCs cultured on DBM were significantly enhanced both in the growth culture medium and the osteogenic culture medium. The organic elements of bone may exhibit greater osteogenic differentiation effects on hPDLCs than the inorganic elements.