Sexual Experimentation in Heterosexual, Bisexual, Lesbian/Gay, and Questioning Adolescents From Ages 11 to 15.

To examine adolescent sexuality development, we analyzed data from a British cohort study (N = 5,070), which assessed the same 12-14 sexual activities at ages 11, 12, 13, and 15, and sexual orientation identity at age 15. The sexual activities ranged from low (e.g., cuddling), moderate (e.g., kissing), to high (e.g., sexual intercourse) intensity. We found that most adolescents having sexual activities of low-to-moderate intensity with same-sex individuals also had them with other-sex individuals, and adolescents having other-sex contacts of low intensity often reported them nonexclusively. Furthermore, other-sex and same-sex sexual activities did not reliably distinguish between sexual orientation identities. Sex differences in these phenomena were absent or small. These findings suggest that many adolescents have low-intensity nonexclusive sexual behaviors.A Gates Cambridge Scholarship and an honorary Cambridge Australia Scholarship awarded to J. T. M. Davis. Research funding awarded to G. Li from the Department of Psychology, University of Cambridg

Weighted entropy and optimal portfolios for risk-averse Kelly investments

Following a series of works on capital growth investment, we analyse log-optimal portfolios where the return evaluation includes `weights' of different outcomes. The results are twofold: (A) under certain conditions, the logarithmic growth rate leads to a supermartingale, and (B) the optimal (martingale) investment strategy is a proportional betting. We focus on properties of the optimal portfolios and discuss a number of simple examples extending the well-known Kelly betting scheme. An important restriction is that the investment does not exceed the current capital value and allows the trader to cover the worst possible losses. The paper deals with a class of discrete-time models. A continuous-time extension is a topic of an ongoing study

A Comparison of Accuracy of Image- versus Hardware-based Tracking Technologies in 3D Fusion in Aortic Endografting

OBJECTIVES: Fusion of three-dimensional (3D) computed tomography and intraoperative two-dimensional imaging in endovascular surgery relies on manual rigid co-registration of bony landmarks and tracking of hardware to provide a 3D overlay (hardware-based tracking, HWT). An alternative technique (image-based tracking, IMT) uses image recognition to register and place the fusion mask. We present preliminary experience with an agnostic fusion technology that uses IMT, with the aim of comparing the accuracy of overlay for this technology with HWT. METHOD: Data were collected prospectively for 12 patients. All devices were deployed using both IMT and HWT fusion assistance concurrently. Postoperative analysis of both systems was performed by three blinded expert observers, from selected time-points during the procedures, using the displacement of fusion rings, the overlay of vascular markings and the true ostia of renal arteries. The Mean overlay error and the deviation from mean error was derived using image analysis software. Comparison of the mean overlay error was made between IMT and HWT. The validity of the point-picking technique was assessed. RESULTS: IMT was successful in all of the first 12 cases, whereas technical learning curve challenges thwarted HWT in four cases. When independent operators assessed the degree of accuracy of the overlay, the median error for IMT was 3.9 mm (IQR 2.89-6.24, max 9.5) versus 8.64 mm (IQR 6.1-16.8, max 24.5) for HWT (p = .001). Variance per observer was 0.69 mm(2) and 95% limit of agreement ±1.63. CONCLUSION: In this preliminary study, the error of magnitude of displacement from the "true anatomy" during image overlay in IMT was less than for HWT. This confirms that ongoing manual re-registration, as recommended by the manufacturer, should be performed for HWT systems to maintain accuracy. The error in position of the fusion markers for IMT was consistent, thus may be considered predictable

Does self-monitoring of blood glucose improve outcome in type 2 diabetes? The Fremantle Diabetes Study

AIMS/HYPOTHESIS: To assess whether self-monitoring of blood glucose (SMBG) is an independent predictor of improved outcome in a community-based cohort of type 2 diabetic patients. MATERIALS AND METHODS: We used longitudinal data from (1) 1,280 type 2 diabetic participants in the observational Fremantle Diabetes Study (FDS) who reported SMBG and diabetes treatment status at study entry (1993–1996), and (2) a subset of 531 participants who attended six or more annual assessments (referred to as the 5-year cohort). Diabetes-related morbidity, cardiac death and all-cause mortality were ascertained at each assessment, supplemented by linkage to the Western Australian Data Linkage System. RESULTS: At baseline, 70.2% (898 out of 1,280) of type 2 patients used SMBG. During 12,491 patient-years of follow-up (mean 9.8 ± 3.5 years), 486 (38.0%) type 2 participants died (196 [15.3%] from cardiac causes). SMBG was significantly less prevalent in those who died during follow-up than in those who were still alive at the end of June 2006 (65.4 vs 73.0%, p = 0.005). In Cox proportional hazards modelling, after adjustment for confounding and explanatory variables, SMBG was not independently associated with all-cause mortality, but was associated with a 79% increased risk of cardiovascular mortality in patients not treated with insulin. For the 5-year cohort, time-dependent SMBG was independently associated with a 48% reduced risk of retinopathy. CONCLUSIONS/INTERPRETATION: SMBG was not independently associated with improved survival. Inconsistent findings relating to the association of SMBG with cardiac death and retinopathy may be due to confounding, incomplete covariate adjustment or chance

Introduction of a Team Based Approach to Radiation Dose Reduction in the Enhancement of the Overall Radiation Safety Profile of FEVAR

OBJECTIVES: Fenestrated endovascular aneurysm repair (FEVAR) exposes operators and patients to considerable amounts of radiation. Introduction of fusion of three-dimensional (3D) computed tomography (CT) with intraoperative fluoroscopy puts new focus on advanced imaging techniques in the operating environment and has been found to reduce radiation and facilitate faster repair. The aim of this study is to evaluate the radiation dose effect of introducing a team-based approach to complex aortic repair. METHODS: Procedural details for a cohort of 21 patients undergoing FEVAR after fusion-guided (Modern Group) imaging was introduced are compared with 21 patients treated in the immediate 12 months prior to implementation (Historic Group) at a centre with expertise in FEVAR. Non-parametric tests were used to compare procedure time (PT), air kerma, dose-area product (DAP), fluoroscopy time (FT), estimated blood loss (EBL) and pre- and post-operative estimated glomerular filtration rate (eGFR) between the groups. RESULTS: Change in operative approach resulted in a significant reduction in PT for the Modern group (median 285 mins; interquartile range 268–322) compared with the Historic group (450 mins; IQR 360–540 p = <0.001). There were reductions in skin dose for the Modern group (1.6 Gy; IQR 1.09–2.1) compared with the Historic group (4.4 Gy; 3.2–7.05 p = <0.001), and DAP (Modern 159 Gy.cm2; IQR 123–226 vs 264.93 Gy.cm2; 173.3–366.8 for Historic (p = 0.006). There were no significant differences in FT, and pre- and post-operative eGFR between the two groups. Weight and height were distributed equally across both groups. Structured dose reports including the changes in frame rate were not available for analysis. CONCLUSIONS: Implementation of a team-based approach to radiation reduction significantly reduces radiation dose. These findings suggest that the radiation safety awareness that accompanies the introduction of fusion imaging may improve the overall radiation safety profile of FEVAR for patients and providers

Women undergoing endovascular thoracoabdominal aortic aneurysm repair differ significantly from their male counterparts preoperatively and postoperatively

OBJECTIVE: A rational approach to the management of aortic aneurysm disease relies on weighing the risk of aneurysm rupture against the complications and durability of operative repair. In men, seminal studies of infrarenal aortic aneurysm disease and its endovascular management can provide a reasoned argument for the timing and modality of surgery, which is then extrapolated to the management of thoracoabdominal aortic aneurysms (TAAAs). In contrast, there is less appreciation for the natural history of TAAA disease in women and its response to therapy. METHODS: We used a retrospective cohort design of women, all men, and matched men, fit for complex endovascular thoracoabdominal aneurysm repair at two large aortic centers. We controlled for preoperative anatomic and comorbidity differences, and assessed technical success, postoperative renal dysfunction, spinal ischemia, and early mortality. Women and matched men were reassessed at follow-up for long-term durability and survival. RESULTS: Assessing women and all men undergoing complex endovascular aortic reconstruction, we demonstrate that these groups are dissimilar before the intervention with respect to comorbidities, aneurysm extent, and aneurysm size; women have a higher proportion of proximal Crawford extent 1, 2, and 3 aneurysms. Matching men and women for demographic and anatomic differences, we find persistent elevated perioperative mortality in women (16%) undergoing endovascular thoracoabdominal aneurysm repair compared with matched men (6%); however, at the 3-year follow-up, both groups have the same survival. Furthermore, women demonstrate more favorable anatomic responses to aneurysm exclusion, with good durability and greater aneurysm sac regression at follow-up, compared with matched men. CONCLUSIONS: Women and unmatched men with TAAA disease differ preoperatively with respect to aneurysm extent and comorbidities. Controlling for these differences, after complex endovascular aneurysm repair, there is increased early mortality in women compared with matched men. These observations argue for a careful risk stratification of women undergoing endovascular thoracoabdominal aneurysm treatment, balanced with women's good long-term survival and durability of endovascular aneurysm repair

Converting Boundary Representation Solid Models to Half-Space Representation Models for Monte Carlo Analysis

Solid modeling computer software systems provide for the design of three-dimensional solid models used in the design and analysis of physical components. The current state-of-the-art in solid modeling representation uses a boundary representation format in which geometry and topology are used to form three-dimensional boundaries of the solid. The geometry representation used in these systems is cubic B-spline curves and surfaces--a network of cubic B-spline functions in three-dimensional Cartesian coordinate space. Many Monte Carlo codes, however, use a geometry representation in which geometry units are specified by intersections and unions of half-spaces. This paper describes an algorithm for converting from a boundary representation to a half-space representation

Responsible modelling: Unit testing for infectious disease epidemiology

Infectious disease epidemiology is increasingly reliant on large-scale computation and inference. Models have guided health policy for epidemics including COVID-19 and Ebola and endemic diseases including malaria and tuberculosis. Yet a coding bug may bias results, yielding incorrect conclusions and actions causing avoidable harm. We are ethically obliged to make our code as free of error as possible. Unit testing is a coding method to avoid such bugs, but it is rarely used in epidemiology. We demonstrate how unit testing can handle the particular quirks of infectious disease models and aim to increase the uptake of this methodology in our field

Responsible modelling: Unit testing for infectious disease epidemiology

Infectious disease epidemiology is increasingly reliant on large-scale computation and inference. Models have guided health policy for epidemics including COVID-19 and Ebola and endemic diseases including malaria and tuberculosis. Yet a coding bug may bias results, yielding incorrect conclusions and actions causing avoidable harm. We are ethically obliged to make our code as free of error as possible. Unit testing is a coding method to avoid such bugs, but it is rarely used in epidemiology. We demonstrate how unit testing can handle the particular quirks of infectious disease models and aim to increase the uptake of this methodology in our field

Impact of inactivated poliovirus vaccine on mucosal immunity: implications for the polio eradication endgame.

The polio eradication endgame aims to bring transmission of all polioviruses to a halt. To achieve this aim, it is essential to block viral replication in individuals via induction of a robust mucosal immune response. Although it has long been recognized that inactivated poliovirus vaccine (IPV) is incapable of inducing a strong mucosal response on its own, it has recently become clear that IPV may boost immunity in the intestinal mucosa among individuals previously immunized with oral poliovirus vaccine. Indeed, mucosal protection appears to be stronger following a booster dose of IPV than oral poliovirus vaccine, especially in older children. Here, we review the available evidence regarding the impact of IPV on mucosal immunity, and consider the implications of this evidence for the polio eradication endgame. We conclude that the implementation of IPV in both routine and supplementary immunization activities has the potential to play a key role in halting poliovirus transmission, and thereby hasten the eradication of polio