Trends of oral cavity, oropharyngeal and laryngeal cancer incidence in Scotland (1975 - 2012) - a socioeconomic perspective

Aim: To examine current incidence trends (1975–2012) of oral cavity (OCC), oropharyngeal (OPC) and laryngeal cancer in Scotland by socioeconomic status (SES). Methods: We included all diagnosed cases of OCC (C00.3-C00.9, C02-C06 excluding C2.4), OPC (C01, C2.4, C09-C10, C14) and laryngeal cancer (C32) on the Scottish Cancer Registry (1975–2012) and annual midterm population estimates by age, sex, geographic region and SES indices (Carstairs 1991 and Scottish Index of Multiple Deprivation 2009). Age-standardized incidence rates were computed and adjusted Poisson regression rate-ratios (RR) compared subsites by age, sex, region, SES and year of diagnosis. Results: We found 28,217 individuals (19,755 males and 8462 females) diagnosed with head and neck cancer (HNC) over the study period. Between 1975 and 2012, relative to the least deprived areas, those living in the most deprived areas exhibited the highest RR (>double) of OCC, OPC and laryngeal cancer, and an almost dose-like response was observed between SES and HNC incidence. Between 2001 and 2012, this socioeconomic inequality tended to increase over time for OPC and laryngeal cancer but remained relatively unchanged for OCC. Incidence rates increased markedly for OPC, decreased for laryngeal cancer and remained stable for OCC, particularly in the last decade. Males exhibited significantly higher RRs compared to females, and the peak age of incidence of OPC was slightly lower than the other subsites. Conclusion: Contrary to reports that OPC exhibits an inverse socioeconomic profile, Scotland country-level data show that those from the most deprived areas consistently have the highest rates of head and neck cancers

Optimal Hashing in External Memory

Hash tables are a ubiquitous class of dictionary data structures. However, standard hash table implementations do not translate well into the external memory model, because they do not incorporate locality for insertions. Iacono and Patrasu established an update/query tradeoff curve for external-hash tables: a hash table that performs insertions in O(lambda/B) amortized IOs requires Omega(log_lambda N) expected IOs for queries, where N is the number of items that can be stored in the data structure, B is the size of a memory transfer, M is the size of memory, and lambda is a tuning parameter. They provide a complicated hashing data structure, which we call the IP hash table, that meets this curve for lambda that is Omega(log log M + log_M N). In this paper, we present a simpler external-memory hash table, the Bundle of Arrays Hash Table (BOA), that is optimal for a narrower range of lambda. The simplicity of BOAs allows them to be readily modified to achieve the following results: - A new external-memory data structure, the Bundle of Trees Hash Table (BOT), that matches the performance of the IP hash table, while retaining some of the simplicity of the BOAs. - The Cache-Oblivious Bundle of Trees Hash Table (COBOT), the first cache-oblivious hash table. This data structure matches the optimality of BOTs and IP hash tables over the same range of lambda

Predictors of Clinically Significant Depression Symptoms as Determined by PHQ-9

Background: Depression is a debilitating and potentially life-threatening mental illness that is very common. Thus, finding predictors of depression is of paramount importance. This study examined household size, high sensitivity C-reactive protein, and select dietary nutrients for possible links to depression. Methods: Data from the 2017-2018 cycle of the National Health and Nutrition Examination Survey (NHANES) was used. Depression was determined based on a PHQ-9 score of 10 or above. Of the 9,254 participants in the overall survey, 4,692 were included in this study. The survey package was used in R to account for the study design and sample weights. Household size 7+ was combined with household size 6 due to low cell size. Results: No nutrients were included in the final model due to lack of significance at the univariate level. HSCRP had a p-value of 0.022 in a univariate model and p-value of 0.053 in the final model. Household size had an overall p-value of less than 0.001 in the final model, and household sizes of 4 and 5 had p-values below 0.05. Conclusion: HSCRP was not statistically significant in the final model, and the difference in the p-value between the univariate model and the final model is most likely explained by the inclusion of BMI in the final model. Household size was found to have an overall statistically significant effect in the final model, with household sizes 4 and 5 in particular having lower odds of depression than a single-person household. Therefore, it may be worthwhile to inform young adults that people who live with 3 or 4 other people are less likely to be depressed

Extended two-body problem for rotating rigid bodies

A new technique that utilizes surface integrals to find the force, torque and potential energy between two non-spherical, rigid bodies is presented. The method is relatively fast, and allows us to solve the full rigid two-body problem for pairs of spheroids and ellipsoids with 12 degrees of freedom. We demonstrate the method with two dimensionless test scenarios, one where tumbling motion develops, and one where the motion of the bodies resemble spinning tops. We also test the method on the asteroid binary (66391) 1999 KW4, where both components are modelled either as spheroids or ellipsoids. The two different shape models have negligible effects on the eccentricity and semi-major axis, but have a larger impact on the angular velocity along the $z$-direction. In all cases, energy and total angular momentum is conserved, and the simulation accuracy is kept at the machine accuracy level.Comment: 24 pages, 9 figures, accepted for publication in Celestial Mechanics and Dynamical Astronom

Dynamics of asteroid systems post-rotational fission

publishedVersio

Inequalities in the dental health needs and access to dental services among looked after children in Scotland: a population data linkage study

Background: There is limited evidence on the health needs and service access among children and young people who are looked after by the state. The aim of this study was to compare dental treatment needs and access to dental services (as an exemplar of wider health and well-being concerns) among children and young people who are looked after with the general child population. Methods: Population data linkage study utilising national datasets of social work referrals for ‘looked after’ placements, the Scottish census of children in local authority schools, and national health service’s dental health and service datasets. Results: 633 204 children in publicly funded schools in Scotland during the academic year 2011/2012, of whom 10 927 (1.7%) were known to be looked after during that or a previous year (from 2007–2008). The children in the looked after children (LAC) group were more likely to have urgent dental treatment need at 5 years of age: 23%vs10% (n=209/16533), adjusted (for age, sex and area socioeconomic deprivation) OR 2.65 (95% CI 2.30 to 3.05); were less likely to attend a dentist regularly: 51%vs63% (n=5519/388934), 0.55 (0.53 to 0.58) and more likely to have teeth extracted under general anaesthesia: 9%vs5% (n=967/30253), 1.91 (1.78 to 2.04). Conclusions: LAC are more likely to have dental treatment needs and less likely to access dental services even when accounting for sociodemographic factors. Greater efforts are required to integrate child social and healthcare for LAC and to develop preventive care pathways on entering and throughout their time in the care system

Iceberg Hashing: Optimizing Many Hash-Table Criteria at Once

Despite being one of the oldest data structures in computer science, hash tables continue to be the focus of a great deal of both theoretical and empirical research. A central reason for this is that many of the fundamental properties that one desires from a hash table are difficult to achieve simultaneously; thus many variants offering different trade-offs have been proposed. This paper introduces Iceberg hashing, a hash table that simultaneously offers the strongest known guarantees on a large number of core properties. Iceberg hashing supports constant-time operations while improving on the state of the art for space efficiency, cache efficiency, and low failure probability. Iceberg hashing is also the first hash table to support a load factor of up to $1 - o(1)$ while being stable, meaning that the position where an element is stored only ever changes when resizes occur. In fact, in the setting where keys are $\Theta(\log n)$ bits, the space guarantees that Iceberg hashing offers, namely that it uses at most $\log \binom{|U|}{n} + O(n \log \log n)$ bits to store $n$ items from a universe $U$, matches a lower bound by Demaine et al. that applies to any stable hash table. Iceberg hashing introduces new general-purpose techniques for some of the most basic aspects of hash-table design. Notably, our indirection-free technique for dynamic resizing, which we call waterfall addressing, and our techniques for achieving stability and very-high probability guarantees, can be applied to any hash table that makes use of the front-yard/backyard paradigm for hash table design

Code wars: steganography, signals intelligence, and terrorism

This paper describes and discusses the process of secret communication known as steganography. The argument advanced here is that terrorists are unlikely to be employing digital steganography to facilitate secret intra-group communication as has been claimed. This is because terrorist use of digital steganography is both technically and operationally implausible. The position adopted in this paper is that terrorists are likely to employ low-tech steganography such as semagrams and null ciphers instead

Determinants of long-term survival in a population-based cohort study of patients with head and neck cancer from Scotland

Background: We investigated long‐term survival from head and neck cancer (HNC) using different survival approaches. Methods: Patients were followed‐up from the Scottish Audit of Head and Neck Cancer. Overall survival and disease‐specific survival were calculated using the Kaplan–Meier method. Net survival was calculated by the Pohar‐Perme method. Mutually adjusted Cox proportional hazards models were used to determine the predictors of survival. Results: A total of 1820 patients were included in the analyses. Overall survival at 12 years was 26.3% (24.3%, 28.3%). Disease‐specific survival at 12 years was 56.9% (54.3%, 59.4%). Net survival at 12 years was 41.4% (37.6%, 45.1%). Conclusion: Determinants associated with long‐term survival included age, stage, treatment modality, WHO performance status, alcohol consumption, smoking behavior, and anatomical site. We recommend that net survival is used for long‐term outcomes for HNC patients—it disentangles other causes of death, which are overestimated in overall survival and underestimated in disease‐specific survival