The present study aims to investigate the genotype-phenotype correlation of the hereditary hemochromatosis （HH）, a genetic disorder of iron metabolism, in Matera province （Basilicata, Italy）. Integrating both epid...The present study aims to investigate the genotype-phenotype correlation of the hereditary hemochromatosis （HH）, a genetic disorder of iron metabolism, in Matera province （Basilicata, Italy）. Integrating both epidemiological and molecular approaches, the authors studied： （a） the frequency of the HH main mutations; （b） the association between mutations and HH cases. The majority of patients with HH are homozygous for the C282Y mutation of the HFE gene. A second mutation （H63D） is more widely distributed and its connection with HH isn＇t clear, but a low penetrance is attributed to this variant. The population-based study consists of three steps： （1） determination of iron biochemical parameters, （2） genetic test, and （3） sequencing of HFE gene and bioinformatics studies. A case report is presented in a 41-year-old male （genotype： H63D/wt） with biochemical and clinical evidences of HH, in absence of secondary iron overload factors. In the cohort of studied patients （150M：62F）, there are 18 homozygous patients; H63D/H63D genotype is found in 11 cases. In the heterozygous group, H63D/wt is the predominant genotype （61/68 subjects）. All the H63D/wt residents in the same village （Mont.） show altered biochemical parameter levels. In our case study, a substitution localized into the HFE promoter （nt225A 〉 C） is found. Results show that the H63D genotype is responsible for most cases of HH. The peculiar clinical manifestation found in Mont. suggests a founder effect. In our case, the iron overload is related to a presence of an undetected mutation, critical for the transcriptional regulation of the HFE gene.展开更多
In this paper, we study the fractional-order biological population models （FI3PMs） with Malthusian~ Verhulst, and porous media laws. The fractional derivative is defined in Caputo sense. The optimal homotopy asympto...In this paper, we study the fractional-order biological population models （FI3PMs） with Malthusian~ Verhulst, and porous media laws. The fractional derivative is defined in Caputo sense. The optimal homotopy asymptotic method （OHAM） for partial differ- ential equations （PDEs） is extended and successfully implemented to solve FBPMs. Third-order approximate solutions are obtained and compared with the exact solutions. The numerical results unveil that the proposed extension in the OHAM for fractional- order differential problems is very effective and simple in computation. The results reveal the effectiveness with high accuracy and extremely efficient to handle most complicated biological population models.展开更多
Ecological regime shift is the rapid transition from one stable community structure to another, often ecologically infe- rior, stable community. Such regime shifts are especially common in shallow marine communities, ...Ecological regime shift is the rapid transition from one stable community structure to another, often ecologically infe- rior, stable community. Such regime shifts are especially common in shallow marine communities, such as the transition of kelp forests to algal turfs that harbour far lower biodiversity. Stable regimes in communities are a result of balanced interactions be- tween species, and predicting new regimes therefore requires an evaluation of new species interactions, as well as the resilience of the ＇stable＇ position. While computational optimisation techniques can predict new potential regimes, predicting the most likely community state of the various options produced is currently educated guess work. In this study we integrate a stable regime op- timisation approach with a Bayesian network used to infer prior knowledge of the likely stress of climate change （or, in practice, any other disturbance） on each component species of a representative rocky shore community model. Combining the results, by calculating the product of the match between resilient computational predictions and the posterior probabilities of the Bayesian network, gives a refined set of model predictors, and demonstrates the use of the process in determining community changes, as might occur through processes such as climate change. To inform Bayesian priors, we conduct a review of molecular approaches applied to the analysis of the transcriptome of rocky shore organisms, and show how such an approach could be linked to meas- ureable stress variables in the field. Hence species-specific microarrays could be designed as biomarkers of in situ stress, and used to inform predictive modelling approaches such as those described here.展开更多
We propose an efficient numerical method for two population models, based on the nonstandard finite difference （NSFD） schemes and composition methods with complex time steps. The NSFD scheme is able to give positive...We propose an efficient numerical method for two population models, based on the nonstandard finite difference （NSFD） schemes and composition methods with complex time steps. The NSFD scheme is able to give positive numerical solutions that satisfy the conservation law, which is a key property for biological population models. The accuracy is improved by using the composition methods with complex time steps. Numerical tests on the plankton nutrient model and whooping cough model are presented to show the efficiency and advantage of the proposed numerical method.展开更多
文摘The present study aims to investigate the genotype-phenotype correlation of the hereditary hemochromatosis （HH）, a genetic disorder of iron metabolism, in Matera province （Basilicata, Italy）. Integrating both epidemiological and molecular approaches, the authors studied： （a） the frequency of the HH main mutations; （b） the association between mutations and HH cases. The majority of patients with HH are homozygous for the C282Y mutation of the HFE gene. A second mutation （H63D） is more widely distributed and its connection with HH isn＇t clear, but a low penetrance is attributed to this variant. The population-based study consists of three steps： （1） determination of iron biochemical parameters, （2） genetic test, and （3） sequencing of HFE gene and bioinformatics studies. A case report is presented in a 41-year-old male （genotype： H63D/wt） with biochemical and clinical evidences of HH, in absence of secondary iron overload factors. In the cohort of studied patients （150M：62F）, there are 18 homozygous patients; H63D/H63D genotype is found in 11 cases. In the heterozygous group, H63D/wt is the predominant genotype （61/68 subjects）. All the H63D/wt residents in the same village （Mont.） show altered biochemical parameter levels. In our case study, a substitution localized into the HFE promoter （nt225A 〉 C） is found. Results show that the H63D genotype is responsible for most cases of HH. The peculiar clinical manifestation found in Mont. suggests a founder effect. In our case, the iron overload is related to a presence of an undetected mutation, critical for the transcriptional regulation of the HFE gene.
文摘In this paper, we study the fractional-order biological population models （FI3PMs） with Malthusian~ Verhulst, and porous media laws. The fractional derivative is defined in Caputo sense. The optimal homotopy asymptotic method （OHAM） for partial differ- ential equations （PDEs） is extended and successfully implemented to solve FBPMs. Third-order approximate solutions are obtained and compared with the exact solutions. The numerical results unveil that the proposed extension in the OHAM for fractional- order differential problems is very effective and simple in computation. The results reveal the effectiveness with high accuracy and extremely efficient to handle most complicated biological population models.
文摘Ecological regime shift is the rapid transition from one stable community structure to another, often ecologically infe- rior, stable community. Such regime shifts are especially common in shallow marine communities, such as the transition of kelp forests to algal turfs that harbour far lower biodiversity. Stable regimes in communities are a result of balanced interactions be- tween species, and predicting new regimes therefore requires an evaluation of new species interactions, as well as the resilience of the ＇stable＇ position. While computational optimisation techniques can predict new potential regimes, predicting the most likely community state of the various options produced is currently educated guess work. In this study we integrate a stable regime op- timisation approach with a Bayesian network used to infer prior knowledge of the likely stress of climate change （or, in practice, any other disturbance） on each component species of a representative rocky shore community model. Combining the results, by calculating the product of the match between resilient computational predictions and the posterior probabilities of the Bayesian network, gives a refined set of model predictors, and demonstrates the use of the process in determining community changes, as might occur through processes such as climate change. To inform Bayesian priors, we conduct a review of molecular approaches applied to the analysis of the transcriptome of rocky shore organisms, and show how such an approach could be linked to meas- ureable stress variables in the field. Hence species-specific microarrays could be designed as biomarkers of in situ stress, and used to inform predictive modelling approaches such as those described here.
文摘We propose an efficient numerical method for two population models, based on the nonstandard finite difference （NSFD） schemes and composition methods with complex time steps. The NSFD scheme is able to give positive numerical solutions that satisfy the conservation law, which is a key property for biological population models. The accuracy is improved by using the composition methods with complex time steps. Numerical tests on the plankton nutrient model and whooping cough model are presented to show the efficiency and advantage of the proposed numerical method.
