Australia is the sixth largest country (in area) in the world with a total area of over 7.5 million km2 (3 million miles2). To date much of the research and policy activity in the dental workforce ...has been based on simple statistical analysis including practitioner-to-population ratios; however, risks are associated with the application of these types of ratios. This study examined practice-to-population (PtP) ratios as a measure of accessibility.
The Tipton kangaroo rat (Dipodomys nitratoides nitratoides; TKR) is listed as endangered both Federally and by the state of California due to profound habitat loss throughout its range in the ...southern San Joaquin Valley of California. Habitat loss is still occurring and critical needs for TKR include identifying occupied sites, quantifying optimal habitat conditions, and conserving habitat. Our objectives were to (1) conduct surveys to identify sites where TKR were extant, (2) assess habitat attributes on all survey sites, (3) generate a GIS-based model of TKR habitat suitability, (4) use the model to determine the quantity and quality of remaining TKR habitat, and (5) use these results to develop conservation recommendations. We surveyed for TKR on 44 sites by live-trapping and detected TKR on 15 sites. Sites with TKR tended to have larger alkali scalds and no obvious sign of past tilling compared to sites without TKR. Also, sites with TKR usually had relatively sparse ground cover and seepweed (Suaeda nigra) was present. The non-protected Heermann’s kangaroo rat (Dipodomys heermanni), a larger competitor, was either absent or present in relatively low numbers at sites with TKR, and when present its abundance was inversely related to that of TKR. Based on our habitat suitability modeling, an estimated 30,000 ha of moderately high or high quality TKR habitat and 60,000 ha of lower or medium quality habitat remain. However, habitat is still being lost and conversion of at least one survey site with TKR occurred during this project. Recommendations for TKR conservation are to (1) conduct additional TKR surveys on unsurveyed but suitable sites, (2) conserve suitable habitat on unprotected lands, (3) manage vegetation on occupied sites if necessary, (4) restore disturbed lands to increase suitability for TKR, and (5) research methods and conduct translocations of TKR to unoccupied sites with suitable habitat.
Dentistry across the globe faces significant workforce issues with mal-distribution at most levels of analysis being a substantial issue. This study was the first to apply high resolution Geographic ...Information Systems (GIS) tools to map every private dental practice in the State of Indiana against a backdrop of population demographics. The hypothesis tested in the study is that there is an even density distribution of dental practices across Indiana.
Adult population data were obtained from the United States Census of Population and divided by census tracts. The physical address for each dental practice in Indiana was collated from a comprehensive web-based search and the two datasets were integrated using GIS tools.
The whole adult population of Indiana (5 million) was distributed across 1,511 census tracts. Across these tracts a total of 2,096 separate private general dental practices were distributed. There were a total of 679 tracts (45%) without a dental practice while 2.5% of tracts had 8 or more practices.
The practice to population ratio (1:2,384) for the whole State was not significantly different for those living within 50km (31 miles) or 25km (15 miles) of the seven major city centers, and mean personal income (by residency location) did not appear to significantly influence practice location.
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Background: Chemoradiation (CRT) with cis or anti-EGFR Ab has been shown to improve survival of patients with stage III-IV HNC. Since Lap, a dual EGFR and HER2 inhibitor, has shown ...effectiveness with CRT in a pilot non-HPV HNC cohort, the RTOG Foundation launched a phase II trial to test the hypothesis that adding Lap to the RT-cis for frontline therapy of stage III-IV Non-HPV HNC improves progression-free survival (PFS). Methods: Patients with stage III-IV carcinoma of the oropharynx (p16-negative), larynx, and hypopharynx, having Zubrod performance of 0-1, and meeting predefined blood chemistry criteria were enrolled after providing consent. Patients were randomized (1:1) to 70 Gy (6 weeks) + 2 cycles of CDDP (q3 weeks) plus either Lap (1500 mg daily, Arm A) or placebo (Arm B) starting 1 week prior to RT and concurrent with RT and for 3 months post RT. PFS was the primary endpoint. The protocol specified 69 PFS events (142 patients) for the final analysis based on HR = 0.65, 80% power, 1-sided alpha 0.20, and one interim efficacy and futility analysis at 50% information. PFS rates between arms for all randomized patients were compared by 1-sided log-rank test (1-sided alpha 0.1803). Overall survival (OS) was a secondary endpoint. Results: From 10/’12 to 04/’17, 142 patients were enrolled, of whom 127 were randomized, 63 to Arm A and 64 to Arm B. Arms A vs B, respectively, were similar in baseline patient characteristics, radiation delivery, completing ≥ 70 Gy (85.7% vs. 82.8%) and cisplatin delivery, completing 200 (±5%) mg/m
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(65.1% vs 70.3%), but dissimilar in Lap/placebo delivery (median dose, 87000 mg vs. 125250 mg). Median follow-up was 4.1 years for surviving patients. The final analysis suggests no improvement in PFS of adding Lap to CRT (HR A/B: 0.91, 95% confidence interval CI 0.56-1.46; P= 0.34; 2-year rates: 50.6%, CI 37.5-63.7% vs. 56.2% CI 43.0-69.4%), or in OS (HR: 1.06, CI 0.61-1.86; P = 0.58; 2-year rates: 71.8% CI 60.1-83.5% vs. 76% CI 64.5-87.4%), death within 30 days of therapy (3.3% vs. 3.4%), and overall treatment-related grade 3-5 adverse event rate (86.7% vs. 84.7%). Grade 3-4 mucositis rates on Arm A and Arm B were 21.7% vs. 23.7%, all grade dysphagia and rash rates were 43.3% vs. 59.3%, and 13.3% vs. 6.8%, respectively. Conclusions: The addition of Lap to the radiation-cisplatin platform did not improve progression-free or overall survival in unselected non-HPV HN. Thus, dual EGFR, HER-2 inhibition does not appear to enhance the effects of chemoradiation. Although we showed that accrual to a non-HPV HN specific trial is feasible, new strategies must be investigated to improve the outcome for this poor prognosis HN population.
Abstract
The radiation from accreting X-ray pulsars was expected to be highly polarized, with some estimates for the polarization degree of up to 80%. However, phase-resolved and energy-resolved ...polarimetry of X-ray pulsars is required in order to test different models and to shed light on the emission processes and the geometry of the emission region. Here we present the first results of the observations of the accreting X-ray pulsar Vela X-1 performed with the Imaging X-ray Polarimetry Explorer. Vela X-1 is considered to be the archetypal example of a wind-accreting, high-mass X-ray binary system, consisting of a highly magnetized neutron star accreting matter from its supergiant stellar companion. The spectropolarimetric analysis of the phase-averaged data for Vela X-1 reveals a polarization degree (PD) of 2.3% ± 0.4% at the polarization angle (PA) of −47.°3 ± 5.°4. A low PD is consistent with the results obtained for other X-ray pulsars and is likely related to the inverse temperature structure of the neutron star atmosphere. The energy-resolved analysis shows the PD above 5 keV reaching 6%–10% and a ∼90° difference in the PA compared to the data in the 2–3 keV range. The phase-resolved spectropolarimetric analysis finds a PD in the range 0%–9% with the PA varying between −80° and 40°.
Piperazine‐based drugs, such as N‐benzylpiperazine (BZP), became attractive in the 2000s due to possessing effects similar to amphetamines. Herein, BZP, in addition to its pyridyl analogues, 2‐, 3‐, ...and 4‐pyridylmethylpiperidine (2‐PMP, 3‐PMP, and 4‐PMP respectively) was subjected to the hyperpolarisation technique Signal Amplification By Reversible Exchange (SABRE) in order to demonstrate the use of this technique to detect these piperazine‐based drugs. Although BZP was not hyperpolarised via SABRE, 2‐PMP, 3‐PMP, and 4‐PMP were, with the ortho‐ and meta‐pyridyl protons of 4‐PMP showing the largest enhancement of 313‐fold and 267‐fold, respectively, in a 1.4‐T detection field, following polarisation transfer at Earth's magnetic field. In addition to the freebase, 4‐PMP.3HCl was also appraised by SABRE and was found not to polarise, however, the addition of increasing equivalents of triethylamine (TEA) produced the freebase, with a maximum enhancement observed upon the addition of 3 equivalents of TEA. Further addition of TEA led to a reduction in the observed enhancement. SABRE was also employed to polarise 4‐PMP.3HCl (~20% w/w) in a simulated tablet to demonstrate the forensic application of the technique (138‐fold enhancement for the ortho‐pyridyl protons). The amount of 4‐PMP.3HCl present in the simulated tablet was quantified via NMR using D2O as a solvent and compared well to complimentary gas chromatography–mass spectrometry data. Exchanging D2O for CD3OD as the solvent utilised for analysis resulted in a significantly lower amount of 4‐PMP.3HCl being determined, thus highlighting safeguarding issues linked to drug abuse in relation to determining the amount of active pharmaceutical ingredient present.
BZP, in addition to its pyridyl analogues, 2‐, 3‐, and 4‐ pyridylmethylpiperidine (2‐PMP, 3‐PMP and 4‐PMP respectively) are subjected to the hyperpolarisation technique SABRE (Signal Amplification By Reversible Exchange) in order to demonstrate the use of this technique to detect these piperazine‐based drugs
To compare the accuracy of standard supplementary views and GE digital breast tomosynthesis (DBT) for assessment of soft-tissue mammographic abnormalities.
Women recalled for further assessment of ...soft-tissue abnormalities were recruited and received standard supplementary views (typically spot compression views) and two-view GE DBT. The added value of DBT in the assessment process was determined by analysing data collected prospectively by radiologists working up the cases. Following anonymization of cases, there was also a retrospective multireader review. The readers first read bilateral standard two-view digital mammography (DM) together with the supplementary mammographic views and gave a combined score for suspicion of malignancy on a five-point scale. The same readers then read bilateral standard two-view DM together with two-view DBT. Pathology data were obtained. Differences were assessed using receiver operating characteristic analysis.
The study population was 342 lesions in 322 patients. The final diagnosis was malignant in 113 cases (33%) and benign/normal in 229 cases (67%). In the prospective analysis, the performance of two-view DM plus DBT was at least equivalent to the performance of two-view DM and standard mammographic supplementary views-the area under the curve (AUC) was 0.946 and 0.922, respectively, which did not reach statistical significance. Similar results were obtained for the retrospective review-AUC was 0.900 (DBT) and 0.873 (supplementary views), which did not reach statistical significance.
The accuracy of GE DBT in the assessment of screen detected soft-tissue abnormalities is equivalent to the use of standard supplementary mammographic views.
The vast majority of evidence relating to the use of DBT has been gathered from research using Hologic equipment. This study provides evidence for the use of the commercially available GE DBT system demonstrating that it is at least equivalent to supplementary mammographic views in the assessment of soft-tissue screen-detected abnormalities.
In Australia, over the past 30 years, the prevalence of dental decay in children has reduced significantly, where today 60-70% of all 12-year-olds are caries free, and only 10% of children have more ...than two decayed teeth. However, many studies continue to report a small but significant subset of children suffering severe levels of decay.
The present study applies Monte Carlo simulation to examine, at the national level, 12-year-old decayed, missing or filled teeth and shed light on both the statistical limitation of Australia's reporting to date as well as the problem of targeting high-risk children.
A simulation for 273 000 Australian 12-year-old children found that moving from different levels of geographic clustering produced different statistical influences that drive different conclusions. At the high scale (ie state level) the gross averaging of the non-normally distributed disease burden masks the small subset of disease bearing children. At the much higher acuity of analysis (ie local government area) the risk of low numbers in the sample becomes a significant issue.
The results clearly highlight the importance of care when examining the existing data, and, second, opportunities for far greater levels of targeting of services to children in need. The sustainability (and fairness) of universal coverage systems needs to be examined to ensure they remain highly targeted at disease burden, and not just focused on the children that are easy to reach (and suffer the least disease).
Introduction: Australia is one of the least densely populated countries in the world, with a population concentrated on or around coastal areas. Up to 33% of the Australian population are likely to ...have untreated dental decay, while people with inadequate dentition (fewer than 21 teeth) account for up to 34% of Australian adults. Historically, inadequate access to public dental care has resulted in long waiting lists, received much media coverage and been the subject of a new federal and state initiative. The objective of this research was to gauge the potential for reducing the national dental waiting list through geographical advantage, which could arise from subcontracting the delivery of subsidised dental care to the existing network of private dental clinics across Australia.
Methods: Eligible population data were collected from the Australian Bureau of Statistics website. Waiting list data from across Australia were collected from publicly available sources and confirmed through direct communication with each individual state or territory dental health body. Quantum geographic information system software was used to map distribution of the eligible population across Australia by statistical area, and to plot locations of government and private dental clinics. Catchment areas of 5 km for metropolitan clinics and 5 km and 50 km for rural clinics were defined. The number of people on the waiting list and those eligible for subsidised dental care covered by each of the catchment areas was calculated. Percentage of the eligible population and those on the waiting list that could benefit from the potential improvement in geographic access was ascertained for metropolitan and rural residents.
Results: Fifty three percent of people on the waiting list resided within metropolitan areas. Rural and remote residents made up 47% of the population waiting to receive care. The utilisation of both government and private dental clinics for the delivery of subsidised dental care to the eligible population has the potential to improve geographic access for up to 25% of those residing within metropolitan areas and up to 59% for eligible country residents.
Conclusions: This research finds that utilisation of the existing network of private dental practices across Australia for delivery of subsidised dental care could dramatically increase geographic reach, reduce waiting lists, and possibly make good oral health a more realistic goal to achieve for the economically disadvantaged members of the community. In addition, this approach has the potential to improve service availability in rural and remote areas for entire communities where existing socioeconomic dynamics do not foster new practice start-up.
Mycobacterium avium ssp. hominissuis, hereafter referred to as M. avium, forms biofilm, a property that, in mice, is associated with lung infection via aerosol. As M. avium might co‐inhabit the ...respiratory tract with other pathogens, treatment of the co‐pathogen‐associated infections, such as in bronchiectasis, would expose M. avium to therapeutic compounds that may have their origin in other organisms sharing the natural environments. Incubation of M. avium with two compounds produced by environmental organisms, streptomycin and tetracycline, in vitro at subinhibitory concentrations increased biofilm formation in a number of M. avium strains, although exposure to ampicillin, moxifloxacin, rifampin and trimethoprim–sulphamethoxazole had no effect on biofilm formation. No selection of genotypically resistant clones was observed. Although incubation of bacteria in the presence of streptomycin upregulates the expression of biofilm‐associated genes, the response to the antibiotics had no association with the expression of a regulator (LysR) linked to the formation of biofilm in M. avium. Biofilms are composed of planktonic and sessile bacteria. Whereas planktonic M. avium is susceptible to clarithromycin and ethambutol (clinically used antimicrobials), sessile bacteria are at least three‐fold to four‐fold more resistant to antibiotics. The sessile phenotype, however, is reversible, and no selection of resistant clones was observed. Mice infected through the airway with both phenotypes were infected with a similar number of bacteria, demonstrating no phenotype advantage. M. avium biofilm formation is enhanced by commonly used compounds and, in the sessile bacterial phenotype, is resistant to clarithromycin and ethambutol, in a reversible manner.
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