The Influence of Tobacco Smoking on the Onset of Periodontitis in Young Persons

This paper reviews the evidence for cigarette smoking as a risk factor for the development of severe destructive periodontal disease in young adults. A high prevalence of cigarette smoking has been identified among young individuals with aggressive periodontitis and tobacco usage increases the risk of periodontal destruction most significantly in young populations. The effect appears to be dose related and is independent of levels of plaque accumulation. Young smokers have more alveolar bone loss and attachment loss than non smoking equivalents. Prolonged and heavy smoking can reduce gingival bleeding and therefore mask the clinical marker of bleeding on probing often used by dentists to monitor periodontal health. This has implications for potential misdiagnosis and failure to detect periodontitis at an early stage. Nicotine metabolites concentrate in the periodontal tissues and can have local effects as well as the potential to affect the systemic host response. Dentists are well placed to assess the smoking status of their young patients and have a role to play in the delivery of smoking cessation advice especially as it pertains to periodontal health. In this way the dental profession can also make a significant contribution to the general health and well being of our youth and future generations

Assessing environmental sustainability using ecological limits expressed as mass flowrates with the inclusion of a sustainable time perspective

This study explores the concept of ecological limits (ELs) for determining the sustainable extraction of natural resources and sustainable discharge of emissions. ELs are expressed as limiting mass flowrates and equations are developed and presented for their quantitative estimation. These include a sustainable time perspective term. This is a time duration that provides sufficient time for humans to adapt to the depletion of a resource stock or emission budget, e.g., the time for a number of human generations. Thus, even if a resource is utilised at a greater rate than its regeneration rate, it could be considered sustainable if the resource extraction rate is adjusted so that the stock continuously lasts for more than the sustainable timeframe. The application of this ecological limits concept is illustrated by applying it to assessing the environmental sustainability of global fossil fuel energy, specific water resources, and global fertilisers. Exceeding ELs can act as a warning signal and highlight those resources and emissions where actions need to be taken to bring their extraction and discharge rates to within the ELs

Characterization of digital-micromirror device-based infrared scene projector

A test procedure is developed for an infrared laser scene projector, and applied to a projection system that we develop based on digital micromirror technology. The intended use will be for simulation and target training. Resolution and noise are significant parameters for target perception models of infrared imaging systems. System resolution is normally measured as the modulation transfer function (MTF), and its noise modeled through an appropriate signal standard deviation metric. We compare MTF measurements for both mid-wave (MWIR) and longwave IR (LWIR) bands for an infrared laser scene projector based on the digital micromirror device (DMD). Moreover, we use two complimentary models to characterize imaging camera noise. This provides a quantitative image-quality criterion of system performance

Understanding how institutions may support the development of transdisciplinary approaches to sustainability research

This article analyses the approaches of academics seeking to engage with private, public and community-based stakeholders through transdisciplinary research about pressing sustainability challenges and, in particular, climate change; it outlines aspects of the institutional factors which influence transdisciplinary research. A qualitative approach was employed in conducting 10 semi-structured interviews to analyse the challenges and motivations of academic researchers when working with a range of other stakeholders through transdisciplinary practice. Two key contributions are made through this work. First, this article adds to the existing literature on motivations and challenges for undertaking research with private, public and community stakeholders in a cross-disciplinary manner. Second, the current institutional circumstances influencing such research practices are outlined, alongside potential ways forward. The research presented here has been undertaken in light of the experiences of the two lead co-authors as early career researchers coming from the disciplines of sociology and energy engineering, engaging in transdisciplinary research within a local community context in relation to a regional energy transition project

Global Models of Runaway Accretion in White Dwarf Debris Disks

A growing sample of white dwarfs (WDs) with metal-enriched atmospheres are accompanied by excess infrared emission, indicating that they are encircled by a compact dusty disk of solid debris. Such `WD debris disks' are thought to originate from the tidal disruption of asteroids or other minor bodies, but the precise mechanism(s) responsible for transporting matter to the WD surface remains unclear, especially in those systems with the highest inferred metal accretion rates dM_Z/dt ~ 1e8-1e10 g/s. Here we present global time-dependent calculations of the coupled evolution of the gaseous and solid components of WD debris disks. Solids transported inwards (initially due to PR drag) sublimate at tens of WD radii, producing a source of gas that accretes onto the WD surface and viscously spreads outwards in radius, where it overlaps with the solid disk. If the aerodynamic coupling between the solids and gaseous disks is sufficiently strong (and/or the gas viscosity sufficiently weak), then gas builds up near the sublimation radius faster than it can viscously spread away. Since the rate of drag-induced solid accretion increases with gas density, this results in a runaway accretion process, during which the WD accretion rate reaches values orders of magnitude higher than can be achieved by PR drag alone. We explore the evolution of WD debris disks across a wide range of physical conditions and calculate the predicted distribution of observed accretion rates dM_Z/dt, finding reasonable agreement with the current sample. Although the conditions necessary for runaway accretion are at best marginally satisfied given the minimal level of aerodynamic drag between circular gaseous and solid disks, the presence of other stronger forms of solid-gas coupling---such as would result if the gaseous disk is only mildly eccentric---substantially increase the likelihood of runaway accretion.Comment: 23 pages, 20 figures, submitted to MNRA

The Revised TESS Input Catalog and Candidate Target List

We describe the catalogs assembled and the algorithms used to populate the revised TESS Input Catalog (TIC), based on the incorporation of the Gaia second data release. We also describe a revised ranking system for prioritizing stars for 2-minute cadence observations, and assemble a revised Candidate Target List (CTL) using that ranking. The TIC is available on the Mikulski Archive for Space Telescopes (MAST) server, and an enhanced CTL is available through the Filtergraph data visualization portal system at the URL http://filtergraph.vanderbilt.edu/tess_ctl.Comment: 30 pages, 16 figures, submitted to AAS Journals; provided to the community in advance of publication in conjunction with public release of the TIC/CTL on 28 May 201

RECQL5 Suppresses Oncogenic JAK2-Induced Replication Stress and Genomic Instability

JAK2V617F is the most common oncogenic lesion in patients with myeloproliferative neoplasms (MPNs). Despite the ability of JAK2V617F to instigate DNA damage in vitro, MPNs are nevertheless characterized by genomic stability. In this study, we address this paradox by identifying the DNA helicase RECQL5 as a suppressor of genomic instability in MPNs. We report increased RECQL5 expression in JAK2V617F-expressing cells and demonstrate that RECQL5 is required to counteract JAK2V617F-induced replication stress. Moreover, RECQL5 depletion sensitizes JAK2V617F mutant cells to hydroxyurea (HU), a pharmacological inducer of replication stress and the most common treatment for MPNs. Using single-fiber chromosome combing, we show that RECQL5 depletion in JAK2V617F mutant cells impairs replication dynamics following HU treatment, resulting in increased double-stranded breaks and apoptosis. Cumulatively, these findings identify RECQL5 as a critical regulator of genome stability in MPNs and demonstrate that replication stress-associated cytotoxicity can be amplified specifically in JAK2V617F mutant cells through RECQL5-targeted synthetic lethality

Prevalence, predictors and perinatal outcomes of peri-conceptional alcohol exposure - retrospective cohort study in an urban obstetric population in Ireland

<p>Abstract</p> <p>Background</p> <p>Evidence-based advice on alcohol consumption is required for pregnant women and women planning a pregnancy. Our aim was to investigate the prevalence, predictors and perinatal outcomes associated with peri-conceptional alcohol consumption.</p> <p>Methods</p> <p>A cohort study of 61,241 women who booked for antenatal care and delivered in a large urban maternity hospital between 2000 and 2007. Self-reported alcohol consumption at the booking visit was categorised as low (0-5 units per week), moderate (6-20 units per week) and high (>20 units per week).</p> <p>Results</p> <p>Of the 81% of women who reported alcohol consumption during the peri-conceptional period, 71% reported low intake, 9.9% moderate intake and 0.2% high intake. Factors associated with moderate alcohol consumption included being in employment OR 4.47 (95% CI 4.17 to 4.80), Irish nationality OR 16.5 (95% CI 14.9 to 18.3), private health care OR 5.83 (95% CI 5.38 to 6.31) and smoking OR 1.86 (95% CI 1.73 to 2.01). Factors associated with high consumption included maternal age less than 25 years OR 2.70 (95% CI 1.86 to 3.91) and illicit drug use OR 6.46 (95% CI 3.32 to 12.60). High consumption was associated with very preterm birth (<32 weeks gestation) even after controlling for socio-demographic factors, adjusted OR 3.15 (95% CI 1.26-7.88). Only three cases of Fetal Alcohol Syndrome were recorded (0.05 per 1000 total births), one each in the low, moderate and high consumption groups.</p> <p>Conclusions</p> <p>Public Health campaigns need to emphasise the importance of peri-conceptional health and pre-pregnancy planning. Fetal Alcohol Syndrome is likely to be under-reported despite the high prevalence of alcohol consumption in this population.</p