Post-printing processing and aging effects on Polyjet materials intended for the fabrication of advanced surgical simulators.

Material Jetting (MJ) 3D printing technology is promising for the fabrication of highly realistic surgical simulators, however, the changes in the mechanical properties of MJ materials after post-printing treatments and over time remain quite unknown. In this study, we investigate the effect of different post-printing processes and aging on the mechanical properties of a white opaque and rigid MJ photopolymer, a white flexible MJ photopolymer and on a combination of them. Tensile and Shore hardness tests were conducted on homogeneous 3D-printed specimens: two different post-printing procedures for support removal (dry and water) and further surface treatment (with glycerol solution) were compared. The specimens were tested within 48 h from printing and after aging (30-180 days) in a controlled environment. All groups of specimens treated with different post-printing processes (dry, water, glycerol) exhibited a statistically significant difference in mechanical properties (i.e. elongation at break, elastic modulus, ultimate tensile strength). Particularly, the treatment with glycerol makes the flexible photopolymer more rigid, but then with aging the initial elongation of the material tends to be restored. For the rigid photopolymer, an increase in deformability was observed as a major effect of aging. The hardness tests on the printed specimens highlighted a significant overestimation of the Shore values declared by the manufacturer. The study findings are useful for guiding the material selection and post-printing processing techniques to manufacture realistic and durable models for surgical training.

Cranio-Maxillofacial Injuries in Mixed Martial Arts.

PURPOSE: To describe a case of a maxillofacial trauma that occurred during a mixed martial arts (MMA) match and to perform a literature review of maxillofacial injuries related to MMA match to determine whether preventive models are applicable. METHODS: The authors described a maxillofacial injury with orbital and optic nerve involvement that happened during a professional MMA match. A literature review on maxillofacial trauma in MMA was conducted on Scopus and Pubmed with specific keywords. RESULTS: Open reduction and internal fixation of the maxillofacial complex fractures with right eye optic neuropathy following an MMA match is described. Six articles were selected for the description of trauma in the maxillofacial complex associated with MMA fights. DISCUSSION: Literature has paid little attention to injuries during MMA matches. The most common injury locations that emerged from the literature review were the head, face, and neck. Middle facial third injuries were the most common type. Frequently the injury involved the ophthalmic area. CONCLUSIONS: The timing of maxillofacial trauma in MMA is critical. Protective devices should be strongly promoted to prevent catastrophic consequences.

Physician density: will we ever close the gap?

OBJECTIVE: Physician density is a crucial element of a well-functioning health system. Previous research has investigated factors affecting country-level physician supply. To date, however, no evidence has been provided about the patterns of convergence in physician density among countries. This paper thus tested club convergence in physician density in 204 countries worldwide from 1990 to 2019. A nonlinear time-varying factor model was adopted to identify potential clubs, wherein groups of countries tend to converge towards the same level of physician density. Our primary purpose was to document the potential long-lasting disparity in future global physician distribution. RESULTS: Despite physician density increasing in all regions globally from 1990 to 2019, we found no evidence in favor of the hypothesis of global convergence. Conversely, the clustering algorithm successfully identified three main patterns (i.e., three final clubs). With few exceptions, the results indicated an uneven physician distribution between the majority of North and Sub-Saharan African countries (where physician density would remain well below the estimated threshold of at least 70% of the Universal Health Coverage Services Index) and the rest of the world. These findings support the WHO's global strategy to reverse the chronic under-investment in human resources for health.

Testing Club Convergence in Female Smoking Prevalence.

In this paper, we applied the concept of convergence to examine the evolution of smoking prevalence among women in 191 countries worldwide from 1990 to 2019. First, the non-linear time-varying factor model proposed by Phillips and Sul was adopted to identify potential clusters (clubs), wherein groups of countries converge to similar female smoking rates. Second, an ordered logit regression model was used to assess the impact of cigarette affordability on the probability of falling within a given cluster. The hypothesis of global convergence was rejected. However, the clustering algorithm successfully identified five and nine clubs, within countries with increasing and decreasing smoking prevalence, respectively. A higher relative income-price ratio (i.e., lower cigarette affordability) increased the likelihood of belonging to a club of countries with a low prevalence of female tobacco smoking.

Does the Prevalence of Obesity Affect the Demand for Soft Drinks? Evidence from Cross-Country Panel Data.

The impact of soft drinks on obesity has been widely investigated during the last decades. Conversely, the role of obesity as a factor influencing the demand for soft drinks remains largely unexplored. However, understanding potential changes in the demand for soft drinks, as a result of changes in the spread of obesity, may be useful to better design a comprehensive strategy to curb soft drink consumption. In this paper, we aim to answer the following research question: Does the prevalence of obesity affect the demand for soft drinks? For this purpose, we collected data in a sample of 97 countries worldwide for the period 2005-2019. To deal with problems of reverse causality, an instrumental variable approach and a two-stage least squares method were used to estimate the impact of the age-standardized obesity rate on the market demand for soft drinks. After controlling for several demographic and socio-economic confounding factors, we found that a one percent increase in the prevalence of obesity increases the consumption of soft drinks and carbonated soft drinks by about 2.37 and 1.11 L per person/year, respectively. Our findings corroborate the idea that the development of an obesogenic food environment is a self-sustaining process, in which obesity and unhealthy lifestyles reinforce each other, and further support the need for an integrated approach to curb soft drink consumption by combining sugar taxes with bans, regulations, and nutrition education programs.

Is the development of obesogenic food environments a self-reinforcing process? Evidence from soft drink consumption.

BACKGROUND: Understanding how the development of obesogenic food environments and the consumption of ultra-processed foods and beverages influence each other can help policymakers to identify effective ways to curb the current obesity epidemic. This paper was designed to investigate whether, and to what extent, the consumption of soft drinks and the prevalence of obesity are linked through feedback effects. METHODS: An ecological study design and a simultaneous equation model were used to investigate the existence of a vicious cycle between the consumption of soft drinks and the prevalence of obesity. The analysis was based on a longitudinal dataset covering per capita sales of soft drinks, the age-standardised prevalence rate of obesity and several demographic and socio-economic control variables in a sample of 98 countries worldwide for the period 2005-2019. RESULTS: Using a Two-Stage Least Squares (2SLS) regression model with fixed effects, we documented a self-reinforcing process that links consumption and obesity. Changes in the spread of obesity were associated with changes in soft drink consumption: a one-unit increase in the age-adjusted prevalence rate of obesity increased consumption by about 2.39 l per person per year. Similarly, as the consumption of soft drinks rose, so did the prevalence of obesity: the age-adjusted rate of obesity increased by 0.07% for every additional litre consumed per capita. Computing the impact multipliers, we found that the outcome of a one-unit decrease in the average price of soft drinks was twofold: a) the prevalence of obesity increased by around 0.17%; and b) consumption increased by around 2.40 l per person, the sum of the increase directly caused by the price reduction (2 l) and the increase due to the interplay between consumption and obesity (0.4 l). CONCLUSIONS: This study has identified a feedback loop between unhealthy habits (i.e. the consumption of soft drinks) and health outcomes (i.e. the prevalence of obesity). This interplay amplifies the impact of any exogenous changes in the determinants of consumption and obesity. These feedback effects should be considered and exploited in planning effective strategies to tackle the burden of obesity and the global epidemic of non-​communicable diseases.

Sugar-sweetened beverage affordability and the prevalence of overweight and obesity in a cross section of countries.

BACKGROUND: A key component of 'obesogenic environments' is the ready availability of convenient, calorie-dense foods, in the form of hyper-palatable and relatively inexpensive ultra-processed products. Compelling evidence indicates that the regular consumption of soft drinks, specifically carbonated and non-carbonated sugar-sweetened beverages (SSBs), has a significant impact on the prevalence of overweight and obesity. However, to implement country-level effective prevention programmes we need to supplement this evidence with quantitative knowledge of the relationships between overweight/obesity and the main determinants of SSB consumption, notably SSB prices and consumers' disposable income. METHOD: Affordability considers the simultaneous effects of both price and disposable income on the buying decision. The purpose of this study was to investigate the effect of SSB affordability on the consumers' purchasing behaviour and weight-related health outcomes. Our study was divided into three parts. First, we computed SSB consumption and affordability for approximately 150 countries worldwide. Second, we estimated a demand function for SSBs to assess the impact of affordability on consumption at the country level. Third, we used a multivariate regression model and country data on the prevalence of overweight and obesity to test the role of SSB affordability in the current obesity epidemic. RESULTS: The analysis reveals that SSB affordability: 1) showed both a large variability across countries and a clear tendency to increase substantially with the level of economic development; 2) played a key role in determining cross-country differences in the amount of soft drink consumed per capita; and 3) was significantly associated with the prevalence rates of both overweight and obesity. Specifically, we show that a 10 % increase in SSB affordability was associated, on average, with approximately 0.4 more overweight/obese adults per 100 inhabitants. CONCLUSIONS: By controlling for the main possible confounding factors, our results clearly indicate that affordability is a major driver of purchasing behaviours and is significantly associated with the prevalence rates of both overweight and obesity. We thus suggest a fiscal approach to curb SSB consumption based on the effectiveness of 'soda taxes' to affect the long-term dynamic of SSB affordability.

Simple vs. Complex Carbohydrate Dietary Patterns and the Global Overweight and Obesity Pandemic.

Nowadays, obesity and being overweight are among the major global health concerns. Many, diet-related diseases impose high tangible and intangible costs, and threaten the sustainability of health-care systems worldwide. In this study, we model, at the macroeconomic level, the impact of energy intake from different types of carbohydrates on the population's BMI (body mass index). We proceed in three steps. First, we develop a framework to analyse both the consumption choices between simple and complex carbohydrates and the effects of these choices on people health conditions. Second, we collect figures for 185 countries (over the period 2012-2014) regarding the shares of simple (sugar and sweetener) and complex (cereal) carbohydrates in each country's total dietary energy supply. Third, we use regression techniques to: (1) estimate the impact of these shares on the country's prevalence of obesity and being overweight; (2) compute for each country an indicator of dietary pattern based on the ratio between simple and complex carbohydrates, weighted by their estimated effects on the prevalence of obesity and being overweight; and (3) measure the elasticity of the prevalence of obesity and being overweight with respect to changes in both carbohydrate dietary pattern and income per capita. We find that unhealthy eating habits and the associated prevalence of excessive body fat accumulation tend to behave as a 'normal good' in low, medium- and high-HDI (Human Development Index) countries, but as an 'inferior good' in very high-HDI countries.

Gender discrimination, gender disparities in obesity and human development.

Measuring gender inequality and women's empowerment is essential to understand the determinants of gender gaps, evaluate policies and monitor countries' progress. With this aim, over the past two decades, research has mainly been directed towards the development of composite indices. The purpose of this paper is to introduce a new and interdisciplinary perspective to the current debate on measuring gender inequality in human development. As a starting point, we develop a simple macroeconomic model of the interdependence between human development and gender inequality. We then introduce a biometric indicator, based on the ratio of female to male body mass index, to measure women's empowerment at the country level. Finally, by using the latest available data, we examine the ability of this biometric indicator to capture countries' performance in achieving gender equality. We obtain five main results: 1) we provide a theoretical framework to explain the joint determination of human development and gender inequality; 2) we show how to use this framework to simulate the impact of exogenous shocks or policy changes; 3) we demonstrate that exogenous changes have a direct and a multiplier effect on human development and gender inequality; 4) we find that the distribution of obesity between the female and male populations represents a useful proxy variable for measuring gender equality at the country level; 5) finally, we use these results to integrate and develop existing knowledge on the 'ecological' approach to the overweight and obesity pandemic.

Unhealthy Behaviours: An International Comparison.

In the current global economy, chronic non-communicable diseases (NCDs) have become the leading cause of death and a major health concern for both developed and developing countries. Among other factors, the worldwide spread of NCDs is driven by the globalisation of unhealthy habits. The purpose of this paper is to develop a simple statistic to measure, at the national level, the average population's exposure to the main NCDs modifiable risk factors. The approach and methodology followed by the United Nations Development Programme to compute the Human Development Index (HDI) is applied to four basic indicators of NCD-related preventable risk factors (alcohol consumption, excess caloric intake, non-balanced diet and tobacco use) in 112 countries worldwide in 2012-14. We obtain a summary composite index, which we call the Unhealthy Behaviour Index (UBI), which ranks countries by the average level of the unhealthy habits (drinking, eating and smoking) of their populations. We find that Belarus and Russian federation are the two countries with the unhealthiest NCD-related lifestyle. With the exception of Canada, the first twenty populations more exposed to the main NCDs preventable risk factors all live in European countries, and mainly in countries of Eastern Europe. Overall, the UBI tends to increase along with the level of human development. In medium, high and very high HDI countries, however, the same level of human development may be associated with very different kinds of NCD-related lifestyles. Finally, economic growth may push populations toward either more unhealthy or healthy habits, depending on the countries' level of development; the elasticity of unhealthy habits with respect to income per capita is positive (but less than one: on average 0.6) until $30,000, decreases as income rises, and becomes negative (around -0.3) in very high income countries.

Perception of forest values in the alpine community of trentino region (Italy).

Values are generally defined as social facts that orientate individual and collective actions, and consequently influence political, economic and social systems. The evaluation of natural resource values is considered an important instrument to support decision making in environmental policy. The forest is an important renewable resource that provides a mix of social, economic and environmental values for society. The paper presents a survey method to collect and analyse individual preferences relating to three macro-categories of forest values. The survey method was tested in the Trentino region (north-east of the Italian Alps) and will soon be extended to other areas. The results of the questionnaires provided evidence that the forest economic value is perceived as least important, while the environmental values were appreciated the most. Regarding the principle social variables, males tended to give higher scores to all three macro-categories compared to females. Moreover, people with a low education also gave higher scores to all three categories in comparison to the more educated individuals.

Surgical removal of a third molar at risk for mandibular pathologic fracture: case report and clinical considerations.

Surgical removal of mandibular deeply impacted third molars may be challenging and could be associated with several possible risks. Intra- or postoperative mandibular fracture during or after third molar extraction is a major though rare complication. Before starting the surgical removal of a mandibular deeply impacted third molar, various predisposing factors of mandibular fracture should be considered and kept in mind: adult age, male sex, deep inclusion, tooth ankylosis, and associated bony pathology. The aim of this article is to report and discuss the surgical management of a mandibular deeply impacted third molar associated with a follicular cyst.

The fate of priority areas for conservation in protected areas: a fine-scale Markov chain approach.

Park managers in alpine areas must deal with the increase in forest coverage that has been observed in most European mountain areas, where traditional farming and agricultural practices have been abandoned. The aim of this study is to develop a fine-scale model of a broad area to support the managers of Paneveggio Nature Park (Italy) in conservation planning by focusing on the fate of priority areas for conservation in the next 50-100 years. GIS analyses were performed to assess the afforestation dynamic over time using two historical maps (from 1859 and 1936) and a series of aerial photographs and ortho-photos (taken from 1954 to 2006) covering a time span of 150 years. The results show an increase in the forest surface area of about 35%. Additionally, the forest became progressively more compact and less fragmented, with a consequent loss of ecotones and open habitats that are important for biodiversity. Markov chain-cellular automata models were used to project future changes, evaluating the effects on a habitat scale. Simulations show that some habitats defined as priority by the EU Habitat Directive will be compromised by the forest expansion by 2050 and suffer a consistent loss by 2100. This protocol, applied to other areas, can be used for designing long-term management measures with a focus on habitats where conservation status is at risk.