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Combining a spatiotemporal, multi-agent based model of a foraging ecosystem with linear, genetically programmed rules for the agents' behaviors results in implicit, endogenous, objective functions and selection algorithms based on "natural selection". Use of this implicit optimization of genetic programs for study of biological systems is tested by application to an artificial foraging ecosystem, and compared with established biological, ecological, and stochastic gene diffusion models. Limited program memory and execution time constraints emulate real-time and concurrent properties of physical and biological systems, and stress test the optimization algorithms. Relative fitness of the agents' programs and efficiency of the resultant populations as functions of these constraints gauge optimization effectiveness and efficiency. Novel solutions confirm the creativity of the optimization process and provide an unique opportunity to experimentally test the neutral code bloating hypotheses. Use of this implicit, endogenous, evolutionary optimization of spatially interacting, genetically programmed agents is thus shown to be novel, consistent with biological systems, and effective and efficient in discovering fit and novel solutions., Comment: 1 table, 4 figures, 1 PDL

Redistribution of resources within a group as a method to reduce wealth inequality is a current area of debate. The evolutionary path to or away from wealth sharing is also a subject of active research. In order to investigate effects and evolution of wealth sharing, societies are simulated using a minimal model of a complex adapting system. These simulations demonstrate, for this artificial foraging society, that local sharing of resources reduces the economy's total wealth and increases wealth inequality. Evolutionary pressures strongly select against local sharing, whether globally or within a individual's clan, and select for asocial behaviors. By holding constant the gene for sharing resources among neighbors, from rich to poor, either with everyone or only within members of the same clan, social behavior is selected but total wealth and mean age are substantially reduced relative to non-sharing societies. The Gini coefficient is shown to be ineffective in measuring these changes in total wealth and wealth distributions, and, therefore, individual well-being. Only with sociality do strategies emerge that allow sharing clans to exclude or coexist with non-sharing clans. These strategies are based on spatial effects, emphasizing the importance of modeling movement mediated community assembly and coexistence as well as sociality., Comment: 2 tables, 1 algorithm PDL, and 8 figures

A simple generative model of a foraging society generates significant wealth inequalities from identical agents on an equal opportunity landscape. These inequalities arise in both equilibrium and non-equilibrium regimes with some societies essentially never reaching equilibrium. Reproduction costs mitigate inequality beyond their affect on intrinsic growth rate. The highest levels of inequality are found during non-equilibrium regimes. Inequality in dynamic regimes is driven by factors different than those driving steady state inequality. Evolutionary pressures drive the intrinsic growth rate as high as possible, leading to a tragedy of the commons., Comment: 12 pages, 2 tables, 5 figures. Presented at the Social Simulation Conference 2021. arXiv admin note: substantial text overlap with arXiv:2101.09817

Single species population models and discrete stochastic gene frequency models are two standards of mathematical biology important for the evolution of populations. An agent based model is presented which reproduces these models and then explores where these models agree and disagree under relaxed specifications. For the population models, the requirement of homogeneous mixing prevents prediction of extinctions due to local resource depletion. These models also suggest equilibrium based on attainment of constant population levels though underlying population characteristics may be nowhere close to equilibrium. The discrete stochastic gene frequency models assume well mixed populations at constant levels. The models' predictions for non-constant populations in strongly oscillating and chaotic regimes are surprisingly good, only diverging from the ABM at the most chaotic levels., Comment: 10 pages, 5 figures. Presented at First International Workshop on Agentization, Rendering Conventional Models with Agent-Based Computing

While the use of spatial agent-based and individual-based models has flourished across many scientific disciplines, the complexities these models generate are often difficult to manage and quantify. This research reduces population-driven, spatial modeling of individuals to the simplest configurations and parameters: an equal resource opportunity landscape with equally capable individuals; and asks the question, "Will valid complex population and inequality dynamics emerge from this simple economic model?" Two foraging economies are modeled: subsistence and surplus. The resulting, emergent population dynamics are characterized by their sensitivities to agent and landscape parameters. The various steady and oscillating regimes of single-species population dynamics are generated by appropriate selection of model growth parameters. These emergent dynamics are shown to be consistent with the equation-based, continuum modeling of single-species populations in biology and ecology. The intrinsic growth rates, carry capacities, and delay parameters of these models are implied for these simple economies. Aggregate measures of individual distributions are used to understand the sensitivities to model parameters. New local measures are defined to describe complex behaviors driven by spatial effects, especially extinctions. This simple economic model is shown to generate significantly complex population and inequality dynamics. Model parameters generating the intrinsic growth rate have strong effects on these dynamics, including large variations in inequality. Significant inequality effects are shown to be caused by birth costs above and beyond their contribution to the intrinsic growth rate. The highest levels of inequality are found during the initial non-equilibrium period and are driven by factors different than those driving steady state inequality., Comment: 29 pages with 22 figures

Optimizing menopausal hormone therapy (MHT) requires an awareness of the benefits and risks associated with the available treatments. This narrative review, which is based on the proceedings of an Advisory Board meeting and supplemented by relevant articles identified in literature searches, examines the role of progestogens in MHT, with the aim of providing practical recommendations for prescribing physicians. Progestogens are an essential component of MHT in menopausal women with a uterus to prevent endometrial hyperplasia and reduce the risk of cancer associated with using unopposed estrogen. Progestogens include natural progesterone, dydrogesterone (a stereoisomer of progesterone), and a range of synthetic compounds. Structural differences and varying affinities for other steroid receptors (androgen, glucocorticoid, and mineralocorticoid) confer a unique biological and clinical profile to each progestogen that must be considered during treatment selection. MHT, including the progestogen component, should be tailored to each woman, starting with an estrogen and a progestogen that has the safest profile with respect to breast cancer and cardiovascular effects, while addressing patient-specific needs, risk factors, and treatment goals. Micronized progesterone and dydrogesterone appear to be the safest options, with lower associated cardiovascular, thromboembolic, and breast cancer risks compared with other progestogens, and are the first-choice options for use in 'special situations,' such as in women with high-density breast tissue, diabetes, obesity, smoking, and risk factors for venous thromboembolism, among others., SCOPUS: re.j, info:eu-repo/semantics/published

The risk for fragility fracture represents a problem of enormous magnitude. It is estimated that only a small fraction of women with this risk take the benefit of preventive measures. The relationship between estrogen and bone mass is well known as they are the other factors related to the risk for fracture. There are precise diagnostic methods, including a tool to diagnose the risk for fracture. Yet there continues to be an under-diagnosis, with the unrecoverable delay in instituting preventive measures. Women under the age of 70 years, being much more numerous than those older, and having risk factors, are a group in which it is essential to avoid that first fragility fracture. Today it is usual not to differentiate between the treatment and the prevention of osteoporosis since the common aim is to prevent fragility fractures. Included in this are women with osteoporosis or with low bone mass and increased risk for fracture, for whom risk factors play a primary role. There is clearly controversy over the type of treatment and its duration, especially given the possible adverse effects of long-term use. This justifies the concept of sequential treatment, even more so in women under the age of 70, since they presumably will need treatment for many years. Bone metabolism is age-dependent. In postmenopausal women under 70 years of age, the increase in bone resorption is clearly predominant, related to a sharp drop in estrogens. Thus a logical treatment is the prevention of fragility fractures by hormone replacement therapy (HRT) and, in asymptomatic women, selective estradiol receptor modulators (SERMs). Afterwards, there is a period of greater resorption, albeit less intense but continuous, when one could utilise anti-resorptive treatments such as bisphosphonates or denosumab or a dual agent like strontium ranelate. Bone formation treatment, such as parathyroid hormone (PTH), in women under 70 years will be uncommon. That is because it should be used in cases where t, Journal Article, SCOPUS: ar.j, info:eu-repo/semantics/published

The risk for fragility fracture represents a problem of enormous magnitude. It is estimated that only a small fraction of women with this risk take the benefit of preventive measures. The relationship between estrogen and bone mass is well known as they are the other factors related to the risk for fracture. There are precise diagnostic methods, including a tool to diagnose the risk for fracture. Yet there continues to be an under-diagnosis, with the unrecoverable delay in instituting preventive measures. Women under the age of 70 years, being much more numerous than those older, and having risk factors, are a group in which it is essential to avoid that first fragility fracture. Today it is usual not to differentiate between the treatment and the prevention of osteoporosis since the common aim is to prevent fragility fractures. Included in this are women with osteoporosis or with low bone mass and increased risk for fracture, for whom risk factors play a primary role. There is clearly controversy over the type of treatment and its duration, especially given the possible adverse effects of long-term use. This justifies the concept of sequential treatment, even more so in women under the age of 70, since they presumably will need treatment for many years. Bone metabolism is age-dependent. In postmenopausal women under 70 years of age, the increase in bone resorption is clearly predominant, related to a sharp drop in estrogens. Thus a logical treatment is the prevention of fragility fractures by hormone replacement therapy (HRT) and, in asymptomatic women, selective estradiol receptor modulators (SERMs). Afterwards, there is a period of greater resorption, albeit less intense but continuous, when one could utilise anti-resorptive treatments such as bisphosphonates or denosumab or a dual agent like strontium ranelate. Bone formation treatment, such as parathyroid hormone (PTH), in women under 70 years will be uncommon. That is because it should be used in cases where t, Journal Article, SCOPUS: ar.j, info:eu-repo/semantics/published

In women experiencing distressing climacteric symptoms during the peri- and postmenopause there is conclusive evidence from abundant randomised controlled trials that systemic hormone replacement therapy (HRT) of any type affords symptom relief, with no alternative treatment producing similar effect. Though this evidence is accumulating, the question of how to provide best clinical practice in an attempt to both alleviate the menopausal symptoms and prevent the more long-term postmenopausal degenerative diseases is still under debate. When providing climacteric medicine, the dose and regimen of HRT needs to be individualised based on the principle of choosing the lowest appropriate dose in relation to severity of symptoms and on the menopausal age. However, few long-term data on different HRT formulations exist in symptomatic women, which also account for baseline risk of cardiovascular disease (CVD), breast cancer and osteoporosis. In most cases, an individualized prescription together with life-style management will sustain possibilities for net beneficial effects on climacteric symptoms, quality of life (QoL), sexuality and osteoporosis, with only rare risk of severe adverse effects. With the perspective provided by recent epidemiological findings, not least from the estrogen only arm of the Women's Health Initiative Study (WHI), European Menopause and Andropause Society (EMAS) supports research activities in symptomatic women with new HRT formulations in order to affect positively the balance of clinical benefit and risk, including specific information on QoL and also account for the traditional differences in treatment modalities between the US and Europe, and the difference in BMI, life-style and diet. In women experiencing an early menopause (<45 year) current data support a specific overall benefit of HRT. At present, more long-term systemic HRT may be considered in women at high risk of osteoporotic fractures, in particular when alternate therapies are eith, Journal Article, Practice Guideline, Research Support, Non-U.S. Gov't, info:eu-repo/semantics/published

In women experiencing distressing climacteric symptoms during the peri- and postmenopause there is conclusive evidence from abundant randomised controlled trials that systemic hormone replacement therapy (HRT) of any type affords symptom relief, with no alternative treatment producing similar effect. Though this evidence is accumulating, the question of how to provide best clinical practice in an attempt to both alleviate the menopausal symptoms and prevent the more long-term postmenopausal degenerative diseases is still under debate. When providing climacteric medicine, the dose and regimen of HRT needs to be individualised based on the principle of choosing the lowest appropriate dose in relation to severity of symptoms and on the menopausal age. However, few long-term data on different HRT formulations exist in symptomatic women, which also account for baseline risk of cardiovascular disease (CVD), breast cancer and osteoporosis. In most cases, an individualized prescription together with life-style management will sustain possibilities for net beneficial effects on climacteric symptoms, quality of life (QoL), sexuality and osteoporosis, with only rare risk of severe adverse effects. With the perspective provided by recent epidemiological findings, not least from the estrogen only arm of the Women's Health Initiative Study (WHI), European Menopause and Andropause Society (EMAS) supports research activities in symptomatic women with new HRT formulations in order to affect positively the balance of clinical benefit and risk, including specific information on QoL and also account for the traditional differences in treatment modalities between the US and Europe, and the difference in BMI, life-style and diet. In women experiencing an early menopause (<45 year) current data support a specific overall benefit of HRT. At present, more long-term systemic HRT may be considered in women at high risk of osteoporotic fractures, in particular when alternate therapies are eith, Journal Article, Practice Guideline, Research Support, Non-U.S. Gov't, info:eu-repo/semantics/published

Women form a large part of many workforces throughout Europe. Many will be working throughout their menopausal years. Whilst the menopause may cause no significant problems for some, for others it is known to present considerable difficulties in both their personal and working lives. During the menopausal transition women report that fatigue and difficulties with memory and concentration can have a negative impact on their working lives. Furthermore, hot flushes can be a source of embarrassment and distress. Some consider that these symptoms can impact on their performance. Greater awareness among employers, together with sensitive and flexible management can be helpful for women at this time. Particular strategies might include: fostering a culture whereby employees feel comfortable disclosing health problems, allowing flexible working, reducing sources of work-related stress, providing easy access to cold drinking water and toilets, and reviewing workplace temperature and ventilation.

Women form a large part of many workforces throughout Europe. Many will be working throughout their menopausal years. Whilst the menopause may cause no significant problems for some, for others it is known to present considerable difficulties in both their personal and working lives. During the menopausal transition women report that fatigue and difficulties with memory and concentration can have a negative impact on their working lives. Furthermore, hot flushes can be a source of embarrassment and distress. Some consider that these symptoms can impact on their performance. Greater awareness among employers, together with sensitive and flexible management can be helpful for women at this time. Particular strategies might include: fostering a culture whereby employees feel comfortable disclosing health problems, allowing flexible working, reducing sources of work-related stress, providing easy access to cold drinking water and toilets, and reviewing workplace temperature and ventilation.

Women form a large part of many workforces throughout Europe. Many will be working throughout their menopausal years. Whilst the menopause may cause no significant problems for some, for others it is known to present considerable difficulties in both their personal and working lives. During the menopausal transition women report that fatigue and difficulties with memory and concentration can have a negative impact on their working lives. Furthermore, hot flushes can be a source of embarrassment and distress. Some consider that these symptoms can impact on their performance. Greater awareness among employers, together with sensitive and flexible management can be helpful for women at this time. Particular strategies might include: fostering a culture whereby employees feel comfortable disclosing health problems, allowing flexible working, reducing sources of work-related stress, providing easy access to cold drinking water and toilets, and reviewing workplace temperature and ventilation.

Women form a large part of many workforces throughout Europe. Many will be working throughout their menopausal years. Whilst the menopause may cause no significant problems for some, for others it is known to present considerable difficulties in both their personal and working lives. During the menopausal transition women report that fatigue and difficulties with memory and concentration can have a negative impact on their working lives. Furthermore, hot flushes can be a source of embarrassment and distress. Some consider that these symptoms can impact on their performance. Greater awareness among employers, together with sensitive and flexible management can be helpful for women at this time. Particular strategies might include: fostering a culture whereby employees feel comfortable disclosing health problems, allowing flexible working, reducing sources of work-related stress, providing easy access to cold drinking water and toilets, and reviewing workplace temperature and ventilation.