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Structural Topology Optimization typically features continuum-based descriptions of the investigated systems. In Part 1 we have proposed a Topology Optimization method for discrete systems and tested it on quasi-static 2D problems of stiffness maximization, assuming linear elastic material. However, discrete descriptions become particularly convenient in the failure and post-failure regimes, where discontinuous processes take place, such as fracture, fragmentation, and collapse. Here we take a first step towards failure problems, testing Discrete Element Topology Optimization for systems with nonlinear material responses. The incorporation of material nonlinearity does not require any change to the optimization method, only using appropriately rich interaction potentials between the discrete elements. Three simple problems are analysed, to show how various combinations of material nonlinearity in tension and compression can impact the optimum geometries. We also quantify the strength loss when a structure is optimized assuming a certain material behavior, but then the material behaves differently in the actual structure. For the systems considered here, assuming weakest material during optimization produces the most robust structures against incorrect assumptions on material behavior. Such incorrect assumptions, instead, are shown to have minor impact on the serviceability of the optimized structures. [ABSTRACT FROM AUTHOR]

The objective of the present study is to give a contribution to the extreme wave climate assessment in the Black Sea, as studies of extreme storm waves are of great interest for coastal protection and maritime traffic. High resolution wind wave data sets are used to investigate trends and variability of the characteristics of extreme storm waves. Two different methodologies (Eulerian and Lagrangean) are applied to 30 years of wave hindcast from 1987 to 2016, over the Black Sea to identify extreme storm waves and also to assess the extreme wave climate. Using the Eulerian methodology, it is observed that extreme storm waves are seasonal, being more frequent during the winter and almost non-existent during the summer. Also, that some areas, as the south-eastern region of the Black Sea more prone to storm generation, in particular, during winter and autumn. For the seven locations near the coast, a considerable inter-annual variability is found in extreme values, but not so much in the mean. Statistical significance in trend adjustment was only found in two locations in the north-western coast, for extreme values. Using a Lagrangean methodology, an inter-annual variability in all storm characteristics that is found, more marked in the annual number of wave storms, maximum area affected by storm waves and maximum length, and less marked for maximum Hs in the storm waves and storm lifetime. [ABSTRACT FROM AUTHOR]

Since its advent in the early 1980s, liposuction has made tremendous advancements, making it the most popular aesthetic surgery performed today. The goal of this Continuing Medical Education (CME) article is to provide a foundation of knowledge of the relevant anatomy, preoperative evaluation, intraoperative technique, and postoperative management for surgeons performing liposuction. Finally, the prevention and management of potential complications will be reviewed along with measures to optimize patient safety and outcomes. [ABSTRACT FROM AUTHOR]

Objective: This study compares the change in midface position following Le Fort III advancement using either rigid external distraction (group 1) or internal distraction (group 2). We hypothesized that, with reference to right-facing cephalometry, internal distraction would result in increased clockwise rotation and inferior displacement of the midface. Design: Le Fort III osteotomies and standardized distraction protocols were performed on 10 cadaveric specimens per group. Right-facing lateral cephalograms were traced and compared across time points to determine change in position at points orbitale, anterior nasal spine (ANS), A-point, and angle ANB. Setting: Institutional. Patients, Participants: Twenty cadaveric head specimens. Interventions: Standard subcranial Le Fort III osteotomies were performed from a coronal approach and adequately mobilized. The specified distraction mechanism was applied and advanced by 15 mm. Main Outcome Measure(s): Changes of position were calculated at various skeletal landmarks: orbitale, ANS, A-point, and ANB. Results: Group 1 demonstrated relatively uniform x-axis advancement with minimal inferior repositioning at the A-point, ANS, and orbitale. Group 2 demonstrated marked variation in x-axis advancement among the 3 points, along with a significant inferior repositioning and clockwise rotation of the midface (P < .0001). Conclusion: External distraction resulted in more uniform advancement of the midface, whereas internal distraction resulted in greater clockwise rotation and inferior displacement. External distraction appears to provide increased vector control of the midface, which is important in creating a customized distraction plan based on the patient’s individual occlusal and skeletal needs. [ABSTRACT FROM AUTHOR]

Damage tolerance is a fundamental prerequisite for the safety and robustness of large complex systems. Here we analyze the response of a system of parallel rods under a damage event. The approach is based on the presence of multiple load paths in a complex structure, that is, various ways to perform a task. We found that, as much as the complexity increases, the presence of effective ways of carrying the load becomes crucial for the robustness of the structural system under a damage process acting at random on the structure. In addition, the size of the system plays an important role: although tendentially more fragile, large systems are able to redistribute and absorb the effects of damage even with low complexity. The results, here discussed with reference to mechanical systems, can be exported to other disciplines. [ABSTRACT FROM AUTHOR]

The efficacy of 1-methylcyclopropene (1-MCP) applied as a post-cutting treatment on fresh-cut 'Queen' pineapple was determined in order to assess its potential to maintain the storage quality of fresh-cut 'Queen' pineapple, a major Philippine variety. 1-MCP at a concentration of 1 uL L-1 was applied post-cutting by injecting the gas into packed fresh-cut 'Queen' pineapples in polypropylene tray overwrapped with LDPE stretchable film. The packed fruits were stored at 5oC and monitored for headspace gas concentrations (ethylene, CO2, O2), visual quality deterioration parameters and microbial deterioration indicators. 1-MCP was found to effectively elicit its ethylene inhibiting action as shown by lowered headspace ethylene by about 40% at day 4 storage. Headspace CO2 levels were likewise lowered by 1-MCP to about 50% at day 2 while higher headspace O2 levels were generally obtained which had the highest increase at day 2 (about 18%) which created an improved modified atmosphere condition inside the package compared with the control. No significant effects on the visual quality were noted throughout storage. Color differences were however observed, with 1-MCP treatments having significantly higher lightness values and higher hue values at day 2. 1-MCP did not affect the microbial growth (aerobic bacteria, acid-forming bacteria, yeasts and molds, coliforms) on the samples during storage. Aerobic bacteria count was slightly lower than the control at day 3. The fresh-cut pineapple packaged in the manner described had a shelf-life of 3 days based on the microbial limits set by EU countries which is log 7 cfu/mL aerobic plate count. To the best of our knowledge, this is the first study which demonstrated the effects of 1-MCP on fresh-cut pineapple of the 'Queen' variety. [ABSTRACT FROM AUTHOR]

Background: Without addressing the constraints specific to disadvantaged populations, national health policies such as universal health coverage risk increasing equity gaps. Health system constraints often have the greatest impact on disadvantaged populations, resulting in poor access to quality health services among vulnerable groups. Methods: The Investment Cases in Indonesia, Nepal, Philippines, and the state of Orissa in India were implemented to support evidence-based sub-national planning and budgeting for equitable scale-up of quality MNCH services. The Investment Case framework combines the basic setup of strategic problem solving with a decision-support model. The analysis and identification of strategies to scale-up priority MNCH interventions is conducted by in-country planners and policymakers with facilitation from local and international research partners. Results: Significant variation in scaling-up constraints, strategies, and associated costs were identified between countries and across urban and rural typologies. Community-based strategies have been considered for rural populations served predominantly by public providers, but this analysis suggests that the scaling-up of maternal, newborn, and child health services requires health system interventions focused on 'getting the basics right'. These include upgrading or building facilities, training and redistribution of staff, better supervision, and strengthening the procurement of essential commodities. Some of these strategies involve substantial early capital expenditure in remote and sparsely populated districts. These supply-side strategies are not only the 'best buys', but also the 'required buys' to ensure the quality of health services as coverage increases. By contrast, such public supply strategies may not be the 'best buys' in densely populated urbanised settings, served by a mix of public and private providers. Instead, robust regulatory and supervisory mechanisms are required to improve the accessibility and quality of services delivered by the private sector. They can lead to important maternal mortality reductions at relatively low costs. Conclusions: National strategies that do not take into consideration the special circumstances of disadvantaged areas risk disempowering local managers and may lead to a "business-as-usual" acceptance of unreachable goals. To effectively guide health service delivery at a local level, national plans should adopt typologies that reflect the different problems and strategies to scale up key MNCH interventions. [ABSTRACT FROM AUTHOR]

The article discusses strategies for development and cost towards improved maternal and child health. It mentions the Investment Case (IC) framework which is a health system research approach that supports maternal, newborn, and child health (MNCH) planning and budgeting. It also notes the identification of constraints hindering the rising of cost-effective MNCH interventions by planners and stakeholders.

This paper deals with the design and off-site construction of particular buildings for critical and emergency situations (e.g., natural disasters such as hurricanes, landslides, floods, and earthquakes; war sites; and desert areas), in which challenging requirements have to be fulfilled. The panel-based system of the ES-KO corporation, which is a major player in this particular market, is described from both the architectural and the engineering points of view. Beyond the classical advantages of off-site systems (e.g., lightness and ease of assembly, speed of construction, transportation, and modularity), specific capacity-design rules can provide high standards of safety durability and structural robustness. Many of these rules can be found in nature, such as exoskeletons, parallelization, redundancy, and compartmentalization. These design issues are suited to particular situations, such as settlements, strong wind, earthquakes, and explosions, because they exploit particular strategies not commonly envisaged in structural design. Moreover, durability ensures the possibility of reusing the modules in different places, reducing the environmental footprint and costs. After describing the architectural modular design of panel-based buildings, which is itself oriented to raise structural performance, an overview of the modern robustness-oriented structural design philosophy is put forward, and its application to ES-KO panels is briefly outlined. [ABSTRACT FROM AUTHOR]

The structural and seismic assessment of the 19th-century Petruzzelli theater in Bari (Italy) is presented. The macro-elements strategy was adopted to dismantle the whole structure in parts. The steel dome was verified through dynamic multi-modal analysis based on finite element model. Each masonry macro-element was firstly verified through a kinematic analysis aiming at excluding local collapse mechanisms. Afterwards, a nonlinear static analysis was carried out in order to evaluate its overall seismic capacity. The effectiveness of linear or nonlinear analyses and of the macro-element strategy compared with other modeling techniques is also discussed. After highlighting the structural deficiencies of the theater, upgrading solutions are proposed with consideration of the safety needs and the architectural preservation requirements based on the historical importance of the building. [ABSTRACT FROM AUTHOR]

The ductility of high-performance fiber-reinforced cementitious concrete (HPFRCC) can be developed not only in tension but also in compression. This aspect is evidenced in the present paper by comparing the behavior of HPFRCC cylindrical specimens under uniaxial compression, with the mechanical response of normal vibrated concrete (NC) and self-consolidating concrete (SCC) subjected to triaxial compression. The ductility of all the cementbased composites is computed through a nondimensional function that relates the inelastic displacement and the relative stress during softening. In the case of NC and SCC specimens, the results show that increasing the confining pressure results in an increase in fracture toughness. Conversely, the tests on HPFRCC specimens show that, even in the absence of confinement, HPFRCC can achieve practically the same ductility observed in normal and selfconsolidating concretes with 1 MPa (0.15 ksi) of confining pressure. Thus, the presence of HPFRCC in compressed columns is sufficient to create an active distributed confinement. [ABSTRACT FROM AUTHOR]

Many empirical equations for predicting the modulus of elasticity as a function of compressive strength can be found in the current literature. They are obtained from experiments performed on a restricted number of concrete specimens subjected to uniaxial compression. Thus, the existing equations cannot cover the entire experimental data. This is due to the fact that mechanical properties of concrete are highly dependent on the types and proportions of binders and aggregates. To introduce a new reliable formula, more than 3000 data sets, obtained by many investigators using various materials, have been collected and analyzed statistically. The compressive strengths of the considered concretes range from 40 to 160 MPa (5.8 to 23.2 ksi). As a result, a practical and universal equation, which also takes into consideration the types of coarse aggregates and mineral admixtures, is proposed. [ABSTRACT FROM AUTHOR]

The analogy between structural progressive collapse and Fracture Mechanics is consistent either for phenomenological, technological and theoretical aspects. In this paper a general energy criterion suitable for fracture in heterogeneous materials is applied to study the progressive collapse of simple structures with cohesive post peak behavior: elementary frames and fiber bundles. The analyses put into evidence some interesting scale effects induced by ductility and dynamics. In particular, a power law describing the decrease of the reduced dynamic critical load with the structural scale and a second order ductile-brittle transition, have been found. These results can be usefully applied in robustness oriented structural design. Moreover, the study of the influence of the extent of the starting damage in structures with different sizes suggests that, the elementary cells of complex framed structures can play a role similar to the microstructure of materials. In conclusion, a new approach to the problem of collapse into complex structures by means of the tools of Fracture Mechanics is proposed. [ABSTRACT FROM AUTHOR]

A sequential time dependent data assimilation scheme based on the Kalman filter is applied to a spectral wave model. Usually, the first guess covariance matrices used in optimal interpolation schemes are exponential spreading functions, which remain constant. In the present work the first guess correlation errors evolve in time according to the dynamic constraints of the wave model. A system error noise is deduced and used to balance numerical errors. The assimilation procedure is tested in a standard situation of swell propagation, where the Kalman filter is used to assimilate the significant wave height. The evolution of the wave field is described by a linear two-dimensional advection equation and the propagation of the error covariance matrix is derived according to Kalman's linear theory. Model simulations were performed in a 2-dimensional domain with deep-water conditions, a relatively small surface area and without wind forcing or dissipation. A true state simulation and a first guess simulation were used to illustrate the assimilation outcome, showing a reasonable performance of the Kalman filter. [ABSTRACT FROM AUTHOR]

The purpose of our study was to compare survival rates of colon carcinoma patients who had undergone attempted curative hepatic resection based on liver staging by computed tomographic angiography (CTA) or portography (CTAP) with previously reported survival rates of patients who underwent similar surgery without preoperative CTAP evaluations. A total of 404 CTAP studies performed at three institutions were reviewed. Of this group, 197 had colon carcinoma. Sixty-nine of the colon patients went to surgery. Actuarial adjusted yearly survival rates were calculated for the prior CTAP colon group and compared to historical controls. The control survival data were taken from reports published prior to the CTAP era. Our study demonstrated no difference in the 1-year survival data between the groups. However, the CTAP patients had greater survival in years 2-4. This greater survival may be multifactorial but in part due to better surgical selection caused by CTAP. [ABSTRACT FROM AUTHOR]

Ultrasound and computed tomography (CT) guided percutaneous needle biopsy of soft tissue lesions was performed in 39 patients. A correct diagnosis was obtained in 35 of 42 biopsies, with an overall accuracy rate of 83%. No false-positive diagnoses were obtained, and no complications related to the procedure were encountered. The value of this technique in the management of selected patients with soft tissue masses is detailed. [ABSTRACT FROM AUTHOR]

A 59-year-old woman was evaluated for a mass in the right lobe of the liver. Ultrasonography (US) demonstrated multiple anechoic areas with enlargement of portal and hepatic veins. These areas were enhanced uniformly after bolus injection of contrast material during computed tomography (CT). The diagnosis of portal-hepatic venous fistula was confirmed by the portal venous phase of a superior mesenteric angiogram. [ABSTRACT FROM AUTHOR]

Background: Without addressing the constraints specific to disadvantaged populations, national health policies such as universal health coverage risk increasing equity gaps. Health system constraints often have the greatest impact on disadvantaged populations, resulting in poor access to quality health services among vulnerable groups.Methods: The Investment Cases in Indonesia, Nepal, Philippines, and the state of Orissa in India were implemented to support evidence-based sub-national planning and budgeting for equitable scale-up of quality MNCH services. The Investment Case framework combines the basic setup of strategic problem solving with a decision-support model. The analysis and identification of strategies to scale-up priority MNCH interventions is conducted by in-country planners and policymakers with facilitation from local and international research partners.Results: Significant variation in scaling-up constraints, strategies, and associated costs were identified between countries and across urban and rural typologies. Community-based strategies have been considered for rural populations served predominantly by public providers, but this analysis suggests that the scaling-up of maternal, newborn, and child health services requires health system interventions focused on 'getting the basics right'. These include upgrading or building facilities, training and redistribution of staff, better supervision, and strengthening the procurement of essential commodities. Some of these strategies involve substantial early capital expenditure in remote and sparsely populated districts. These supply-side strategies are not only the 'best buys', but also the 'required buys' to ensure the quality of health services as coverage increases. By contrast, such public supply strategies may not be the 'best buys' in densely populated urbanised settings, served by a mix of public and private providers. Instead, robust regulatory and supervisory mechanisms are required to improve the accessibility and quality of services delivered by the private sector. They can lead to important maternal mortality reductions at relatively low costs.Conclusions: National strategies that do not take into consideration the special circumstances of disadvantaged areas risk disempowering local managers and may lead to a "business-as-usual" acceptance of unreachable goals. To effectively guide health service delivery at a local level, national plans should adopt typologies that reflect the different problems and strategies to scale up key MNCH interventions. [ABSTRACT FROM AUTHOR]