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Based on multiple global climate models (GCMs), the Standardized Precipitation Evapotranspiration Index ( SPE I) and Intensity-Area-Duration (IAD) method were used to identify drought events of the Indus River Basin (IRB) in the reference period (1986–2005) and under 1.5 °C (2020–2039 in RCP2.6) and 2.0 °C (2040–2059 in RCP4.5) global warming scenarios. Then, the population exposure was assessed by combining drought events with a projected dynamic population amount from five Shared Socioeconomic Pathways (SSPs), in which describe future of societal development considering the effects of climate change and climate policies. Research results show that both precipitation and evapotranspiration are projected to increase with global warming. Due to a higher increase in evapotranspiration than in precipitation, frequency, intensity, and areal coverage of drought events in the IRB are expected to increase under the 1.5 °C and 2.0 °C warming scenarios relative to the 1986–2005 reference period. In particular, frequency and areal coverage of extreme severe droughts will increase significantly. With aggravation of droughts across the IRB, annual population exposure will increase considerably from 43.2 million in 1986-2005 to approximately 114.4 million based on SSP1 (a sustainable world) under the 1.5 °C global warming scenario and will reach 163.1 million based on SSP3 (a strongly fragmented world) under the 2.0 °C scenario. Compared with the 2.0 °C level, maintaining the increase in global average temperature below the 1.5 °C limit can reduce the population exposed to drought by approximately 1.4-fold.

Broadly speaking, institutional reformers decide about the sequencing of types of reforms, either addressing institutional quality or macroeconomic stability. This paper develops a dynamic population game, in which agents play a simple anonymous-exchange game of cooperating or defecting. Agents switch to the strategy with higher expected payoff. Reformers can affect the payoff structure of the stage game in order to maximize the number of cooperators in the population by either enacting legal reform or focusing on the macro outlook of the economy. Reform is cumulative and starts from initial conditions. Reform effort per period of time is capped. On the basis of the theoretical model the paper makes predictions under which conditions which types of reforms should be enacted first and under which conditions reform will not be successful.

This study aimed to assess the applicability of freeze-dried E. faecium NRRL B-2354 (FDE) to evaluate the inactivation efficiency of radio-frequency (RF) pasteurization on wheat flour. FDE was prepared by adding equal volume of 10% skim milk solution as a protectant. Microstructure of FDE was evaluated by scanning and transmission electron microscopy. Thermal resistance parameters of FDE in wheat flour were determined at 75 °C, 80 °C, and 85 °C. A 6 kW, 27.12 MHz RF heating system was used to rapidly pasteurize 3.0 kg wheat flour at 75 °C, 80 °C, and 85 °C, respectively. Population reduction of FDE in the geometric center of flour samples were compared with survivor counts and predicted model. Flour samples were equilibrated to water activity 0.45 measured at 25 °C. The results showed that FDE protected by skim milk were well maintained with repeatable D-values D75°C = 14.27 ± 0.85 min, D80°C = 5.92 ± 0.39 min, and D85°C = 2.79 ± 0.15 min, and z-value of 13.1 °C. RF treatment at 75 °C, 80 °C, and 85 °C for 10 min achieved 1.0-, 2.5-, and 4.9-log reduction of FDE, respectively. In RF pasteurization process, the dynamic population reduction of FDE can be predicted by a model based on F-value. RF treatment provides an effective and rapid approach to inactivate target microorganism in flour samples.

Phylodynamics of Crimean Congo Hemorrhagic fever virus (CCHFV) genotype V in South Russia was analyzed using 244 partial (452–571 nt) sequences in all three genomic segments and 38 complete genomic sequences. Despite increased number of sequences, the Russian lineage of the European genotype V (commonly termed GtVa) was distinct from GtV isolates from Turkey and the Balkan countries. No geographic pattern was observed in phylogenetic subgrouping of CCHFV within South Russia. Identical isolates could be found at distant locations spaced by hundreds of kilometers, while relatively divergent viruses circulated in the same region. Full genome analysis indicated that reassortment events within GtVa occurred every few decades (median half-life of a non-reassortant node 30–40 years) and involved M and S segments. Therefore, in South Russia CCHFV represents a highly dynamic population of frequently reassorting viruses.

Prioritizing habitats for conservation is a challenging task, particularly for species with fluctuating populations and seasonally dynamic habitat needs. Although the use of resource selection models to identify and prioritize habitat for conservation is increasingly common, their ability to characterize important long-term habitats for dynamic populations are variable. To examine how habitats might be prioritized differently if resource selection was directly and dynamically linked with population fluctuations and movement limitations among seasonal habitats, we constructed a spatially explicit individual-based model for a dramatically fluctuating population requiring temporally varying resources. Using greater sage-grouse (Centrocercus urophasianus) in Wyoming as a case study, we used resource selection function maps to guide seasonal movement and habitat selection, but emergent population dynamics and simulated movement limitations modified long-term habitat occupancy. We compared priority habitats in RSF maps to long-term simulated habitat use. We examined the circumstances under which the explicit consideration of movement limitations, in combination with population fluctuations and trends, are likely to alter predictions of important habitats. In doing so, we assessed the future occupancy of protected areas under alternative population and habitat conditions. Habitat prioritizations based on resource selection models alone predicted high use in isolated parcels of habitat and in areas with low connectivity among seasonal habitats. In contrast, results based on more biologically-informed simulations emphasized central and connected areas near high-density populations, sometimes predicted to be low selection value. Dynamic models of habitat use can provide additional biological realism that can extend, and in some cases, contradict habitat use predictions generated from short-term or static resource selection analyses. The explicit inclusion of population dynamics and movement propensities via spatial simulation modeling frameworks may provide an informative means of predicting long-term habitat use, particularly for fluctuating populations with complex seasonal habitat needs. Importantly, our results indicate the possible need to consider habitat selection models as a starting point rather than the common end point for refining and prioritizing habitats for protection for cyclic and highly variable populations.

This study presents an estimate of the total NO2 exposure in a polluted and densely populated region in Malta, the Northern Harbour district. To estimate the population mobility, we follow a dynamic approach whereby four microenvironments are mapped onto defined Copernicus Urban Atlas 2012 land use classifications. These include the home (ME_home), work (ME_work), traffic (ME_traffic), and other outdoor activities (ME_other) microenvironments. In addition, generic time-activity profiles are used to estimate the hourly mobility in the different microenvironments depending on weekday or weekend profiles. Measured hourly NO2 ambient concentrations from the air quality network run by the Environment and Resources Authority (ERA) are used in conjunction with the estimated time-activity profiles to calculate the total exposure. The highest NO2 population exposure is estimated for ME_home (71%) as people spend the majority of the time in this microenvironment followed by ME_other (15%), ME_work (10%) and ME_traffic (4%), respectively. In addition, we test the sensitivity of the total NO2 exposure to changes in NO2 concentrations for different microenvironments. The total NO2 exposure using infiltration rates to estimate infiltrated outdoor NO2 concentrations in indoor microenvironments, is up to 25% lower compared to the NO2 exposure estimated using outdoor NO2 concentrations for all microenvironments. Results also suggest a decrease of 3% in the estimated NO2 exposure if a static population is assumed for each microenvironment as opposed to a dynamic one. Exposure assessments such as that presented in this study are essential to aid the development of targeted policies to limit such exposures.

In order to include viscous instability in modeling heavy oil waterflooding, it is essential to predict the nature of viscous instability. It is still unclear as to whether previous findings of viscous fingering in immiscible displacements in the presence of high single-phase permeabilities and linear displacement schemes are valid in displacement schemes similar to oil-field patterns (e.g., five-spot) and what the effect of dispersion (caused by varying velocity profiles) is on viscous fingering. To overcome the limitations of previous studies of viscous fingering in immiscible displacements, we conduct experiments in low-permeability, one-quarter five-spot patterns. The correlation of experimentally measured oil recoveries, pressure drops, saturation profiles, viscous fingers length and width, dynamic population of fingers, and rate of growth of fingers population with time and front position are discussed. Study of viscous fingering patterns in heavy oil waterflooding conducted in this work provides new insights into the onset of fingering and fingers development.

Dynamic population is one of urban characteristics. Slowness in responding on it can lead to degradation of cities carrying capacity that affects the human wellbeing. To respond the dynamic condition, balancing factors is important to reach the wellbeing. This study attempted to provide another approach to measure the wellbeing levels, namely green wellbeing model by applying carrying capacity as a reference level. The objective of this study is to assess causality among the factors in the Bekasi Municipality as a part of the JMU. Balance scorecards and spatial analysis used to set up the model. The result shows this approach can create a linkage in assessing the achievement of green well-being through the sustainable cities.

We developed a comprehensive, flexible dynamic model that estimates all-cause mortality for a hypothetical cohort. All model input is user-specified. In the base case, members of the cohort may be exposed to a high risk product as they age. The counterfactual scenario includes exposure to both a high risk and a lower risk product. The model sorts the population into age and exposure categories, and applies the appropriate mortality rates to each category. The model tracks individual exposure histories, and estimates, at the end of each modeled age category, the number of survivors in the two exposure scenarios (base case and counterfactual), and the difference between them. Markov Chain Monte Carlo techniques are used to estimate the variability of the results. Model output was compared against US and Swedish life tables using population-specific tobacco exposure transition probabilities derived from the literature, and it produced similar survival estimates.

The eigenvalues of a population projection matrix–except for the Lotka coefficient–are uniquely determined by the reproductive values and the survival. This relation (proposed earlier, but not really well known in western literature) follows from another useful relation between fertility, reproductive values, survival, and Lotka’s coefficient. These results are applied to provide demographic interpretations to the intrinsically dynamic and metastable population models by Schoen and co-workers.

Sensory systems utilize dynamical response properties of neurons to extract features of spatiotemporally varying stimuli. We propose a dynamic population coding of sensory stimuli in which the stimulus features are encoded into a spatiotemporal firing pattern of neuron population. Using electrolocation of weakly electric fish as a model system, we study how the spatiotemporal features of electric field modulated depending on the distance and size of an object are encoded into the spatial distribution and time interval between burst spikes of neuron population. We showed that the information about distance and size of object are represented as a function of the spatial area of and time interval between the synchronous firing of neuron population in a higher nucleus.

Almost all influenza surveillance systems of temperate countries report a single influenza illness peak each winter. Although several strains of different types or subtypes may co-circulate, they exceptionally lead to two distinct illness peaks during the same winter. We hypothesize that cross-protection between the different strains can, by itself, explain this absence of succeeding illness peaks. We used a dynamic population model to describe the spread of two influenza strains during one season. Cross-protection is included through a parameter defined as the reduction of host risk of infection to one strain after infection with another strain. Different scenarios are performed with two strains emerging with different time-lags, for different levels of cross-protection. We show that a cross-protection of 50% between the two strains is sufficient to explain why we observe a single influenza illness peak in temperate countries.

A multi-modal genetic algorithm using a dynamic population concept is introduced. Each image point is assigned a label and for a chromosome to survive, it must have at least one image point with its label. In this way, the genetic algorithm dynamically segments the scene into one or more objects and the background noise. A repeated least square technique is applied to enhance the convergence performance. The integrated algorithm is tested using a 6 degrees-of-freedom template matching problem, and it is applied to a challenging image that contains multiple target objects as well as scene clutter due to unrelated objects.

Environmentally Conscious Manufacturing and Designing for the Environment have become considerably important in the recent years due to the results of sustained high living standards and dynamic population growth. The scope of activity involved is immense. Physical products must not only proceed from “cradle to grave” but now must proceed “cradle to reincarnation”. Business practices must be altered and enhanced to address a multitude of items needed to produce products with less overall environmental impact. This paper presents both the physical product system and the business process system and identifies key areas where the competencies of industrial engineers can best be used.

This paper considers a dynamic allocation problem in which many perishable goods are allocated at each period. Agents want to keep winning goods for more than one period to make profits. We consider efficient and optimal mechanisms when the seller offers simple long-term contracts. The dynamic VCG mechanism achieves efficient allocations. The expected revenue is maximized by the virtual welfare maximization. In the single unit case, price discounts for long-stay agents can be optimal under certain distributions. Both the efficient and optimal mechanisms are implemented by a simple “handicap auction” in the binary length case.

Consider a community of various species newly introduced into a stable environment. Evolutionary processes acting on this community will produce, over time, a community of surviving species. Methods for predicting the evolutionarily stable strategies (ESSs) used by the surviving species are now available for a large class of dynamic population models. Here we expand a previously developed evolutionary game theory, which can be used to predict ESSs in a large class of models, by introducing strategy dynamics. By so doing, a more complete description of the evolutionary process is obtained. One not only obtains a convenient way of determining evolutionarily stable strategies, but interesting features about the evolutionary process itself can be observed. Of particular interest here, we show that the number of strategies which are evolutionarily stable can change as certain environmental factors involved with the model change. The process by which the ESS is formed is examined in terms of an "adaptive landscape" formed by our fitness generating function ( G -function). The G -function has properties that enhance the likelihood that the various adaptive peaks will be occupied.

We survey the recent literature on designing auctions and mechanisms for dynamic settings. Two settings are considered: those with a dynamic population of agents or buyers whose private information remains fixed throughout time; and those with a fixed population of agents or buyers whose private information changes across time. Within each of these settings, we discuss both efficient (welfare-maximizing) and optimal (revenue-maximizing) mechanisms.

We present results of the first nonperturbative calculation of η -meson production in heavy-ion collisions from 0.8 to 2 GeV/u bombarding energy. In this calculation mean-field effects as well as the dynamic population of nucleon resonances and their decay are taken into account. The results obtained are compared with very recent experiments at 1 GeV/u and are analyzed with respect to the time development of the hadronic composition of the reaction volume.

This paper introduces a microsimulation model that simulates the budgetary impact of the 2006 regime change in the Dutch disability scheme. A dynamic population model fits the case of the disability benefits the best. As opposed to macro forecasts, a microsimulation can answer questions about the individual or meso income effects, the exact distribution of expenses among different benefits and the time path of the savings. The introduction of the proposed system change decreases the number of disability benefits by more than 25% from 2020 onwards and reduces total costs by almost Euro 2 billion or 20%. Based on the better incentive structure, participation will increase and boost GDP. Microsimulation can be used to pick the winners and losers of the new system and give the time path of the savings. It is shown that for almost all partially disabled that are working, the total discounted income after the system change is as large as or larger than before the system change, for the non-working total discounted income is lower.

Genetic models of subdivided populations usually assume highly simplified fixed population structures. Studies of social groups of rhesus monkeys (Macaca mulatta) and hamadryas baboons (Papio hamadryas) indicate that populations of these monkeys possess complex, distinctive, highly dynamic population structures. The lack of correspondence between assumptions of ordinary genetic models and observations on real monkey populations seems sufficiently great that existing genetic models for subdivided populations cannot serve as theories for monkey populations. It is suggested that more adequate representations of genetic structures of populations of social species will be built with formalisms borrowed from linguistic and computer sciences.

A previous article [1] presents a simulation model for modeling complex interactions between a dynamic population and its environment. In that article alleles are represented by an ordered pair ( a i , x i ) where the first member a i defines an enzyme (or enzymes) and the second member x i defines a “linkage” factor. In the present article, this model is used to study the process of selection on the crossover probabilities in a small population. It is found that strong selective forces are necessary to drive such a population. These include the possibility of a relatively large number of offspring for a given mating and broad mortality procedures. They are necessary in the face of the stochastic effects to which a small population is subject.