Seasonal changes in hydrology and the distribution of plankton in the Bathurst Harbour estuary, southwestern Tasmania, 1988-89

The hydrology and abundance of planktonic organisms (>20 m size) were surveyed at various sites in the Bathurst Harbour/Port Davey estuary on five occasions between October 1988 and July 1989, and the hydrology again surveyed in February 1991. In winter, the period of peak freshwater outflow, a brackish surface layer(= 15%o) was present to a depth of ~4 m throughout the estuary. This surface layer was present to a reduced depth in other seasons, except during summer, when the halocline broke down and surface salinities of=29%o in 1989 and =25%o in 1991 prevailed. Bottom waters were close to fully marine (~33%0) throughout the year. Surface waters in Bathurst Harbour were found to be extremely depleted in nitrates «0.1 11M). Oxygen levels were also very low (~35% saturation) during the 1989 summer, which was unusually dry, but were near full saturation during the other sampling periods. The plankton community in Bathurst Harbour contained very few taxa, particularly during the winter months. The dinoflagellate Dinophysis acuminata comprised >99% of total phytoplankton numbers in October 1988 and July 1989, while the copepods Gladioferens inermis and Oithona australis and the appendicularian Oikopleura sp. numerically dominated the woplankton community. Dinoflagellates and copepods both occurred in high densities. The distribution of diatoms within the estuary was inversely related to the distribution of dinoflagellates; diatoms occurred in low densities relative to dinoflagellates in Bathurst Harbour outside the summer months, but occurred in much higher densities than dinoflagellates in the waters of Port Davey throughout the year

Macquarie Harbour, Tasmania-seasonal oceanographic surveys in 1985

Seasonal oceanographic surveys of Macquarie Harbour suggested the existence of a three-layer system: a surface layer responsive to seasonal heating and cooling and to river runoff, a slowly changing mid-level layer, and (in the deeper basins) a marine layer fed by tides flooding over the sill

Students’ perceptions of endodontic typodont teeth with simulated canals printed from novel materials

Introduction: This study aimed to investigate students\u27 perceptions of the use of 3D-printed typodonts by implementing a questionnaire and evaluating the students\u27 comparisons between extracted, commercial and 3D-printed teeth.Methods: Ethical approval was obtained (QMER20.586/2021) and questionnaire feedback was collected anonymously using an online survey. A total of 143 fourth- and fifth-year dental students were approached to participate during pre-clinical courses focussing on root canal therapy. The tooth design was based on micro-CT data of an extracted maxillary central incisor and 3D-printed with haptically-similar materials produced in previous work. The questionnaire comprised 11 Likert-scale questions, four open-ended questions, two “yes” or “no” questions and three closed-ended questions.Results: Eighty questionnaires were returned. Overall, the feedback was favourable towards the 3D-printed typodonts compared to the commercial teeth. The biggest difference in responses was in Question 6 related to the realism of drilling the enamel when comparing 3D-printed teeth with commercial ones. Statistical analysis showed a significant difference (p \u3c 0.05); the fourth-year\u27s response on average, was 2.95 (±0.73) an “agree” rating, whereas the fifth-year\u27s response was 3.98 (±0.82) with “neither agree or disagree”.Discussion: Within the limitations of this study, the 3D-printed typodonts were rated high in comparison to the commercial teeth in terms of overall operative experiences

Composite 3D printing of biomimetic human teeth

Human teeth are mechanically robust through a complex structural composite organisation of materials and morphology. Efforts to replicate mechanical function in artificial teeth (typodont teeth), such as in dental training applications, attempt to replicate the structure and morphology of real teeth but lack tactile similarities during mechanical cutting of the teeth. In this study, biomimetic typodont teeth, with morphology derived from X-ray microtomography scans of extracted teeth, were 3D printed using an approach to develop novel composites. These composites with a range of glass, hydroxyapatite and porcelain reinforcements within a methacrylate-based photopolymer resin were compared to six commercial artificial typodont teeth. Mechanical performance of the extracted human teeth and 3D printed typodont teeth were evaluated using a haptic approach of measuring applied cutting forces. Results indicate 3D printed typodont teeth replicating enamel and dentine can be mechanically comparable to extracted human teeth despite the material compositions differing from the materials found in human teeth. A multiple parameter variable of material elastic modulus and hardness is shown to describe the haptic response when cutting through both human and biomimetic, highlighting a critical dependence between the ratio of material mechanical properties and not absolute material properties in determining tooth mechanical performance under the action of cutting forces

Approaches to 3D printing teeth from X-ray microtomography.

Artificial teeth have several advantages in preclinical training. The aim of this study is to three-dimensionally (3D) print accurate artificial teeth using scans from X-ray microtomography (XMT). Extracted and artificial teeth were imaged at 90 kV and 40 kV, respectively, to create detailed high contrast scans. The dataset was visualised to produce internal and external meshes subsequently exported to 3D modelling software for modification before finally sending to a slicing program for printing. After appropriate parameter setting, the printer deposited material in specific locations layer by layer, to create a 3D physical model. Scans were manipulated to ensure a clean model was imported into the slicing software, where layer height replicated the high spatial resolution that was observed in the XMT scans. The model was then printed in two different materials (polylactic acid and thermoplastic elastomer). A multimaterial print was created to show the different physical characteristics between enamel and dentine

Meandering of the subtropical front south-east of the Azores

A subtropical front was observed in the area south and southeast of the Azores during cruises of FS Meteor and FS Poseidon in early 1982. The front has a basically west–east extension, with considerable meandering observed. Meso-scale eddies are found on both sides. The overall flow pattern corresponds to earlier results on geopotential differences in the upper northeast Atlantic, but the baroclinic transport of the order of 107 m3 s−1 is found to be concentrated in a 60-km wide jet. We suggest here that the current band is part of the gyre circulation, resulting from a branching of the North Atlantic Current

Disparities in mammographic screening for Asian women in California: a cross-sectional analysis to identify meaningful groups for targeted intervention

<p>Abstract</p> <p>Background</p> <p>Breast cancer is the most commonly diagnosed cancer among the rapidly growing population of Asian Americans; it is also the most common cause of cancer mortality among Filipinas. Asian women continue to have lower rates of mammographic screening than women of most other racial/ethnic groups. While prior studies have described the effects of sociodemographic and other characteristics of women on non-adherence to screening guidelines, they have not identified the distinct segments of the population who remain at highest risk of not being screened.</p> <p>Methods</p> <p>To better describe characteristics of Asian women associated with not having a mammogram in the last two years, we applied recursive partitioning to population-based data (N = 1521) from the 2001 California Health Interview Survey (CHIS), for seven racial/ethnic groups of interest: Chinese, Japanese, Filipino, Korean, South Asian, Vietnamese, and all Asians combined.</p> <p>Results</p> <p>We identified two major subgroups of Asian women who reported not having a mammogram in the past two years and therefore, did not follow mammography screening recommendations: 1) women who have never had a pap exam to screen for cervical cancer (68% had no mammogram), and 2) women who have had a pap exam, but have no women's health issues (osteoporosis, using menopausal hormone therapies, and/or hysterectomy) nor a usual source of care (62% had no mammogram). Only 19% of Asian women who have had pap screening and have women's health issues did not have a mammogram in the past two years. In virtually all ethnic subgroups, having had pap or colorectal screening were the strongest delineators of mammography usage. Other characteristics of women least likely to have had a mammogram included: Chinese non-U.S. citizens or citizens without usual source of health care, Filipinas with no health insurance, Koreans without women's health issues and public or no health insurance, South Asians less than age 50 who were unemployed or non-citizens, and Vietnamese women who were never married.</p> <p>Conclusion</p> <p>We identified distinct subgroups of Asian women at highest risk of not adhering to mammography screening guidelines; these data can inform outreach efforts aimed at reducing the disparity in mammography screening among Asian women.</p

Protocol for evaluation of the cost-effectiveness of ePrescribing systems and candidate prototype for other related health information technologies

Background: This protocol concerns the assessment of cost-effectiveness of hospital health information technology (HIT) in four hospitals. Two of these hospitals are acquiring ePrescribing systems incorporating extensive decision support, while the other two will implement systems incorporating more basic clinical algorithms. Implementation of an ePrescribing system will have diffuse effects over myriad clinical processes, so the protocol has to deal with a large amount of information collected at various ‘levels’ across the system. Methods/Design: The method we propose is use of Bayesian ideas as a philosophical guide. Assessment of cost-effectiveness requires a number of parameters in order to measure incremental cost utility or benefit – the effectiveness of the intervention in reducing frequency of preventable adverse events; utilities for these adverse events; costs of HIT systems; and cost consequences of adverse events averted. There is no single end-point that adequately and unproblematically captures the effectiveness of the intervention; we therefore plan to observe changes in error rates and adverse events in four error categories (death, permanent disability, moderate disability, minimal effect). For each category we will elicit and pool subjective probability densities from experts for reductions in adverse events, resulting from deployment of the intervention in a hospital with extensive decision support. The experts will have been briefed with quantitative and qualitative data from the study and external data sources prior to elicitation. Following this, there will be a process of deliberative dialogues so that experts can “re-calibrate” their subjective probability estimates. The consolidated densities assembled from the repeat elicitation exercise will then be used to populate a health economic model, along with salient utilities. The credible limits from these densities can define thresholds for sensitivity analyses. Discussion: The protocol we present here was designed for evaluation of ePrescribing systems. However, the methodology we propose could be used whenever research cannot provide a direct and unbiased measure of comparative effectiveness

Importance of lysosomal cysteine proteases in lung disease

The human lysosomal cysteine proteases are a family of 11 proteases whose members include cathepsins B, C, H, L, and S. The biology of these proteases was largely ignored for decades because of their lysosomal location and the belief that their function was limited to the terminal degradation of proteins. In the past 10 years, this view has changed as these proteases have been found to have specific functions within cells. This review highlights some of these functions, specifically their roles in matrix remodeling and in regulating the immune response, and their relationship to lung diseases