Design of adaptive structures through energy minimization: extension to tensegrity.

This paper gives a new formulation to design adaptive structures through total energy optimization (TEO). This methodology enables the design of truss as well as tensegrity configurations that are equipped with linear actuators to counteract the effect of loading through active control. The design criterion is whole-life energy minimization which comprises an embodied part in the material and an operational part for structural adaptation during service. The embodied energy is minimized through simultaneous optimization of element sizing and actuator placement, which is formulated as a mixed-integer nonlinear programming problem. Optimization variables include element cross-sectional areas, actuator positions, element forces, and node displacements. For tensegrity configurations, the actuators are not only employed to counteract the effect of loading but also to apply appropriate prestress which is included in the optimization variables. Actuator commands during service are obtained through minimization of the operational energy that is required to control the state of the structure within required limits, which is formulated as a nonlinear programming problem. Embodied and operational energy minimization problems are nested within a univariate optimization process that minimizes the structure's whole-life energy (embodied + operational). TEO has been applied to design a roof and a high-rise adaptive tensegrity structure. The adaptive tensegrity solutions are benchmarked with equivalent passive tensegrity as well as adaptive truss solutions, which are also designed through TEO. Results have shown that since cables can be kept in tension through active control, adaptive tensegrity structures require low prestress, which in turn reduces mass, embodied energy, and construction costs compared to passive tensegrity structures. However, while adaptive truss solutions achieve significant mass and energy savings compared to passive solutions, adaptive tensegrity solutions are not efficient configurations in whole-life energy cost terms. Since cable elements must be kept in tension, significant operational energy is required to maintain stable equilibrium for adaptation to loading. Generally, adaptive tensegrity solutions are not as efficient as their equivalent adaptive truss configurations in mass and energy cost terms.

Cancer incidence in people with AIDS in Italy.

People with HIV/AIDS (PWHA) have increased risk of some cancers. The introduction of highly active antiretroviral therapies (HAART) has improved their life expectancy, exposing them to the combined consequences of aging and of a prolonged exposure to cancer risk factors. The aim of this study was to estimate incidence rates (IR) in PWHA in Italy, before and after the introduction of HAART, after adjusting for sex and age through direct standardization. An anonymous record linkage between Italian AIDS Registry (21,951 cases) and Cancer Registries (17.3 million, 30% of Italian population) was performed. In PWHA, crude IR, sex- and age-standardized IR and age-specific IR were estimated. The standardized IR for Kaposi sarcoma and non-Hodgkin lymphoma greatly declined in the HAART period. Although the crude IR for all non-AIDS-defining cancers increased in the HAART period, standardized IR did not significantly differ in the 2 periods (352 and 379/100,000, respectively). Increases were seen only for cancer of the liver (IR ratio = 4.6, 95% CI: 1.3-17.0) and lung (IR ratio = 1.8, 95% CI: 1.0-3.2). Age-specific IRs for liver and lung cancers, however, largely overlapped in the 2 periods pointing to the strong influence of the shift in the age distribution of PWHA on the observed upward trends. In conclusion, standardized IRs for non-AIDS-defining cancers have not risen in the HAART period, even if crude IRs of these cancers increased. This scenario calls, however, for the intensification of cancer-prevention strategies, notably smoking cessation and screening programs, in middle-aged HIV-patients.

Estimates of cancer burden in Campania.

AIMS AND BACKGROUND: In Campania two cancer registries have been operating since 1996, covering part of the province of Naples and the province of Salerno, and amounting to 29% of the regional population. The aim of this paper is to provide estimates of the incidence, mortality and prevalence of seven major cancers for the entire Campania region. METHODS: The estimates were obtained by applying the MIAMOD method, a statistical back-calculation approach to derive incidence and prevalence figures starting from mortality and relative survival data. Survival was modeled on the basis of published data from the Italian cancer registries. RESULTS: In 2012 the most frequent cancers were colorectal, breast and lung cancer with 3,969, 3,675 and 3,629 new diagnosed cases, respectively. The cancers with increasing incidence trends were breast cancer, lung cancer and skin melanoma in women, and colorectal cancer and skin melanoma in men. By contrast, the incidence rates of uterine cervix cancer and stomach cancer were decreasing. In men the lung and prostate cancer incidence rates increased, reaching a peak in different periods, and then decreased and stabilized, respectively. Prevalence was increasing for all considered cancers with the exception of cervical cancer. The highest values in 2012 were estimated for breast and colorectal cancer (34,000 and 22,000 prevalent cases, respectively). In the final period under study there was a decline in mortality for all cancers except female lung cancer. The highest crude mortality rates in 2012 were estimated for lung cancer in men and breast cancer in women: 80 and 31 per 100,000, respectively. CONCLUSION: This paper provides a description of the burden of the major cancers in Campania until 2015. The estimates highlight the need to reinforce organized screening, especially for breast and colorectal cancer, and to support evidence-based prevention campaigns against female smoking. All these aspects require continuous and updated monitoring of the main epidemiological indicators in the Campania population.