Transmissible spongiform encephalopathies(TSEs)are a group of progressive and ultimately fatal neurologic diseases of man and animals,all resulting from the propagated misfolding of the host's normal cellular prio...Transmissible spongiform encephalopathies(TSEs)are a group of progressive and ultimately fatal neurologic diseases of man and animals,all resulting from the propagated misfolding of the host's normal cellular prion protein.These diseases can be spontaneous,heritable,anthropogenic/iatrogenic,or in some cases horizontally transmissible,and include such notable TSEs as bovine spongiform encephalopathy(BSE)of cattle and chronic wasting disease(CWD)of cervids.Although they are both unequivocally protein misfolding disorders,they differ markedly in their pathogenesis,transmissibility,and zoonotic potential.While the BSE epidemic has largely abated over the past three decades following global feed bans on ruminant meat and bone meal,CWD,which is readily transmitted through various forms of excreta,has rapidly expanded from its original endemic zone to encompass much of North America,along with recently identified foci in Scandinavia.Most importantly,although the classical form of BSE has proven transmissible to humans consuming contaminated beef or beef products,so far there have been no conclusive reports on the zoonotic transmission of cWD to humans.The underlying basis for these differences-whether host or agent directed-are not well understood,though may be due to inherent differences in the three-dimensional structure of the misfolded BSE or CWD prion proteins or the expression levels and tissue distribution of respective cellular prion proteins.With the uncontrolled geographic spread of CWD,it is imperative that we improve our understanding of the factors governing prion disease pathogenesis,transmission,and zoonotic potential.展开更多
Muscle wasting is defined as the progressive and generalized loss of muscle mass. Muscle depletion is a common feature of chronic liver disease foundin approximately 40% of patients with cirrhosis. Its etiology is mul...Muscle wasting is defined as the progressive and generalized loss of muscle mass. Muscle depletion is a common feature of chronic liver disease foundin approximately 40% of patients with cirrhosis. Its etiology is multifactorial subsequent to liver failure and its prevalence increases along with disease severity. Cross-sectional analytic morphometry using computed tomography(CT) scan or magnetic resonance imaging are considered by consensus the gold standards to assess muscle size in cirrhosis for research purposes because they are not biased by fluid accumulation. Several studies have assessed the impact of muscle wasting on overall survival of patients in the waiting list for liver transplantation and there is a general agreement that decreased muscle size assessed by CT scan is an independent predictor for mortality in cirrhosis. It has been proposed that the addition of cross-sectional muscle area into the Model for End-stage Liver Disease can increase its prognostic performance. Nevertheless, the use of CT scan in assessing muscle size is inappropriate for routine clinical practice and an alternative cost-effective, easy to use and accurate tool should be developed. In conclusion, muscle wasting has a detrimental impact on survival of patients with cirrhosis and, thus, it remains to be elucidated if nutritional interventions and exercise could improve muscle wasting and, subsequently, survival in this setting.展开更多
Rheumatoid arthritis(RA), the commonest inflammatory arthritis, is a debilitating disease leading to functional and social disability. In addition to the joints, RA affects several other tissues of the body including ...Rheumatoid arthritis(RA), the commonest inflammatory arthritis, is a debilitating disease leading to functional and social disability. In addition to the joints, RA affects several other tissues of the body including the muscle. RA patients have significantly less muscle mass compared to the general population. Several theories have been proposed to explain this. High grade inflammation, a central component in the pathophysiology of the disease, has long been proposed as the key driver of muscle wasting. More recent findings however, indicate that inflammation on its own cannot fully explain the high prevalence of muscle wasting in RA. Thus, thecontribution of other potential confounders, such as nutrition and physical activity, has also been studied. Results indicate that they play a significant role in muscle wasting in RA, but again neither of these factors seems to be able to fully explain the condition. Oxidative stress is one of the major mechanisms thought to contribute to the development and progression of RA but its potential contribution to muscle wasting in these patients has received limited attention. Oxidative stress has been shown to promote muscle wasting in healthy populations and people with several chronic conditions. Moreover, all of the aforementioned potential contributors to muscle wasting in RA(i.e., inflammation, nutrition, and physical activity) may promote pro- or antioxidative mechanisms. This review aims to highlight the importance of oxidative stress as a driving mechanism for muscle wasting in RA and discusses potential interventions that may promote muscle regeneration via reduction in oxidative stress.展开更多
The coexistence of different water homeostasis abnormalities following neurosurgery represents a diagnostic and therapeutic challenge for intensive care units. This paper reports the case of a 13 year-old boy who unde...The coexistence of different water homeostasis abnormalities following neurosurgery represents a diagnostic and therapeutic challenge for intensive care units. This paper reports the case of a 13 year-old boy who underwent surgery for a suprasellar tumour and, immediately after surgery, developed a cerebral abscess, persistent diabetes insipidus (DI) as well as cerebral salt wasting syndrome (CSWS). The early onset of CSWS following DI has been associated with a poor prognosis and increased mortality. In cases in which these abnormalities coexist, the increased polyuria secondary to the rise in natriuresis associated with CSWS might be erroneously interpreted as a sign of poor control of the DI, thereby leading to therapeutic mistakes. Treatment basically consists of restoring electrolytes and the joint administration of desmopressin and fludrocortisone.展开更多
AIM To identify patients with end-stage renal disease treated by peritoneal dialysis(PD) who had zero body fat(BF) as determined by analysis of body composition using anthropometric formulas estimating body water(V) a...AIM To identify patients with end-stage renal disease treated by peritoneal dialysis(PD) who had zero body fat(BF) as determined by analysis of body composition using anthropometric formulas estimating body water(V) and to compare nutritional parameters between these patients and PD patients whose BF was above zero.METHODS Body weight(W) consists of fat-free mass(FFM) andBF.Anthropometric formulas for calculating V allow the calculation of FFM as V/0.73,where 0.73 is the water fraction of FFM at normal hydration.Wasting from loss of BF has adverse survival outcomes in PD.Advanced wasting was defined as zero BF when V/0.73 is equal to or exceeds W.This study,which analyzed 439 PD patients at their first clearance study,used the Watson formulas estimating V to identify patients with V_(Watson)/0.73 ≥ W and compared their nutritional indices with those of PD patients with V_(Watson)/0.73 < W.RESULTS The study identified at the first clearance study two male patients with V_(Watson)/0.73 ≥ W among 439 patients on PD.Compared to 260 other male patients on PD,the two subjects with advanced wasting had exceptionally low body mass index and serum albumin concentration.The first of the two subjects also had very low values for serum creatinine concentration and total(in urine and spent peritoneal dialysate) creatinine excretion rate while the second subject had an elevated serum creatinine concentration and high creatinine excretion rate due,most probably,to non-compliance with the PD prescription.CONCLUSION Advanced wasting(zero BF) in PD patients,identified by the anthropometric formulas that estimate V,while rare,is associated with indices of poor somatic and visceral nutrition.展开更多
The aim of the study is to monitor and assess landslide hazards by remote sensing data processing and GIS (Geographic Information Service) spatial analysis. Idukki district, the western Ghats of India was chosen as ...The aim of the study is to monitor and assess landslide hazards by remote sensing data processing and GIS (Geographic Information Service) spatial analysis. Idukki district, the western Ghats of India was chosen as test area, because of frequent destructive mass wasting processes. Western Ghats is a prominent orographic feature that runs parallel to the south west coast of India. Predicting landslide hazard on a regional scale, namely the assessment of actual and potential mass movement over large area is carried out using Remote Sensing and GIS. A numerical weightage to the causative factors of slope instability such as slope, relative relief, aspect, curvature, drainage density, drainage frequency, land use, road buffer and drainage buffer are assigned as per earlier workers for the purpose of landslide susceptibility zonation. A high degree of match is found between observed and predicted landslide hazard by the procedure employed in the study.展开更多
Protein energy wasting (PEW) is a major challenge in CKD. Objective: To assess PEW in predialysis patients on their first visit to a nephrologist. Methods: Three day dietary intake of 484 CKD stage 3 patients was take...Protein energy wasting (PEW) is a major challenge in CKD. Objective: To assess PEW in predialysis patients on their first visit to a nephrologist. Methods: Three day dietary intake of 484 CKD stage 3 patients was taken. Appetite was assessed with ADAT. Patients were divided into groups based on appetite and BMI. Results: Male and female parameters are serum albumin 3.7 ± 0.84/3.68.8 ± 0.81 g/dL, total protein 7.02 ± 1.27/6.94 ± 1.26 g/dL, creatinine 4.68 ± 4.19/3.74 ± 3.36 mg% creatinine clearance 33.22 ± 30.48/37.55 ± 33.87 ml/minute, BMI 22.60 ± 4.29/23.43 ± 4.77kg/m2 energy/kg 16.97 ± 0.65/16.8 ± 0.64, protein g/kg 0.65 ± 0.28/0.64 ± 0.30, carbohydrate g/kg 2.98 ± 1.54/2.98 ± 0.1.36, fat g/kg 2.98 ± 0.23/2.79 ± 0.22, respectively. As appetite decreased, dietary protein and energy intake decreased significantly. Appetite in males and females: Average 14.46%, 4.13%, poor 9.7%, 18.18%, anorexic 13.2%, 7.4%. Income had strong correlation with BMI (p 0.000), dietary protein (p 0.000), energy (p 0.000) and carbohydrate (p 0.000). Appetite correlated with creatinine (p 0.019), dietary energy, protein, carbohydrate and fat (p 0.000) intake. BMI correlated (p 0.000) with fat, carbohydrate, energy and creatinine clearance. ANOVA showed significant difference within and between appetite groups in energy, protein, fat, carbohydrate, creatinine clearance (p 0.000) and serum albumin (p 0.025). There was significant difference in protein (p 0.026), energy intake (p 0.000) and creatinine clearance (p 0.038) within and between BMI groups. Based on income, there was significant difference among groups in BMI (p 0.000), energy (p 0.019), protein (p 0.031) and albumin (0.001).展开更多
Background: The existence and prevalence of cerebral salt wasting and its differentiation from syndrome of inappropriate antidiuretic hormone have been controversial. This controversy stems from overlapping clinical a...Background: The existence and prevalence of cerebral salt wasting and its differentiation from syndrome of inappropriate antidiuretic hormone have been controversial. This controversy stems from overlapping clinical and laboratory findings and an inability to assess the volume status of these patients. Objectives:To present a case of a cerebral salt wasting syndrome secondary to a bacterial mengitis and to emphasize the difficulty to assess the diagnosis. Case report: A 51-year-old male admitted to the ICU for a severe bacterial meningitis who developed, four days later, hyponatremia associated with hypovolemia due to a renal salt wasting. Clinical and biological parameters were collected;electrolytes balances and salt clearances were calculated to best investigate this hydroelectrolytic disorder. Patient's volume status and improvement after fluid and sodium replacement highly suggests the diagnosis of a cerebral salt wasting syndrome. Conclusion: A thorough analysis of this case showed that occurrence of hyponatremia and renal salt wasting after brain agression is not univocal underlying the fact that the diagnosis of cerebral salt wasting should be assessed only after a careful examination of the different determinants of the hydroelectrolytical balance.展开更多
The purpose of the research was to obtain the mass wasting hazard map for the state of Vargas, central coast of Venezuela, using GIS technology. The work was developed through the heuristic method with the generation ...The purpose of the research was to obtain the mass wasting hazard map for the state of Vargas, central coast of Venezuela, using GIS technology. The work was developed through the heuristic method with the generation of thematic digital maps, univariate statistical treatment, weighting of each variable and quantifying the relationship of each parameter unit regarding mass wasting processes. The algorithm designed to perform map algebra was designed using the variables: surface geology, slope, slope orientation, terrain curvature, moisture topographic index, power index surface flow rate and capacity sediment transport and the rate normalized difference vegetation. The results show a distribution of landslide hazard with the highest values in the west central part of Vargas state, where the dominant lithology is incompetent, and combined with topographic elements, determining high instability, meanwhile the lower hazard areas were found in specific areas such as the middle watershed areas east of the state. The calibration of this model shows a reliability of 80%, so it is highly advisable to use the information generated in this work by governmental and non-governmental organizations in the planning, management and use of land.展开更多
<strong>Background:</strong> Malnutrition is a strong predictor of prognosis in maintenance hemodialysis patients (MHD). We previously proposed a new and simple protein-energy wasting (PEW) score that appe...<strong>Background:</strong> Malnutrition is a strong predictor of prognosis in maintenance hemodialysis patients (MHD). We previously proposed a new and simple protein-energy wasting (PEW) score that appears to be useful for assessing the risk of mortality in patients on MHD. <strong>Objectives: </strong>In the present study, we evaluated the reliability of this PEW score as a predictor of hospitalization in Japanese patients on MHD. <strong>Methods:</strong> In this single-center, prospective cohort study conducted in Japan, PEW score was calculated for 180 MHD patients. PEW score ranged from 0 (best: S1) to 4 (worst: S4) and was calculated based on nutritional indicators including serum albumin, body mass index, serum creatinine level, and protein intake. The outcome was the number of hospitalizations during the 2-year study period. <strong>Results:</strong> Thirty-six patients were hospitalized during the study period. Kaplan-Meier curves showed there were fewer hospitalizations in the group with a PEW score of 0/1 than in the group with a score of 3/4. Multivariate analysis revealed a hazard ratio for hospitalization of 3.109 for S3/4 versus S0, 2.777 for S3/4 versus S1, and 2.048 for S3/4 versus S2.<strong> Conclusion:</strong> The new and simple PEW score is a useful predictor of hospitalization in MHD patients and is also useful for identifying subgroups of MHD patients with a high risk of mortality.展开更多
Introduction: A higher risk of death is associated with wasting in children if it is not treated properly. The objective of this study was to investigate the ionic disorders observed in infants suffering from severe w...Introduction: A higher risk of death is associated with wasting in children if it is not treated properly. The objective of this study was to investigate the ionic disorders observed in infants suffering from severe wasting at Yalgado Ouedraogo Teaching Hospital (YO-TH) and at Charles de Gaulle Pediatric Teaching Hospital (CDG-PTH) in Ouagadougou (Burkina Faso). Methods: This was a retrospective study with a descriptive and analytical aim over the period from January 1, 2016 to December 31, 2020. Results: It concerned infants aged 6 to 24 months hospitalized at YO-TH and at CDG-PTH from Ouagadougou. We included 271 infants. The mean age of the infants was 14.48 ± 5.44 months with 42.07% which was in the age range of [12 - 18] months. On admission to the hospital, the children had an average weight, height and BMI of 6.22 ± 1.32 kg, 0.73 ± 0.07 m and 11.67 ± 1.53 kg/m<sup>2</sup>. In urban areas 56.46% of children and the main reasons for consultation were fever (88.19%), vomiting (52.80%) and diarrhea (50.20%). Electrolyte disturbances in emaciated infants affected all 8 parameters of the blood ionogram. However, the major disorders were 65.68% hyponatremia, 55.35% hypobicarbonatemia, 41.33% hypoprotidemia and 32.47% hypokalemia in infants aged 6 to 24 months. We found an association between diarrhea and residence with hypokalemia (p = 0.0000) and hypochloremia (p = 0.010), respectively. Conclusion: Severe acute wasting in infants 6 to 24 months of age remains a concern in the hospital setting. The frequency of biochemical disturbances is also high.展开更多
Research shows that workers drift from their contracted tasks to personal email,social networks and the far corners of the internet for anything between a few hours a week to a few hours a day.Six out of 10people admi...Research shows that workers drift from their contracted tasks to personal email,social networks and the far corners of the internet for anything between a few hours a week to a few hours a day.Six out of 10people admit they can’t get through the workday without checking their social media.展开更多
Background Muscle wasting is a common clinical phenomenon that affects at least 20 percent of patients with heart failure. The exercise capacity of heart failure patients is limited; if left unchecked, which can form ...Background Muscle wasting is a common clinical phenomenon that affects at least 20 percent of patients with heart failure. The exercise capacity of heart failure patients is limited; if left unchecked, which can form ca- chexia, seriously affecting the quality of life of patients with heart failure. This paper summarizes the clinical manifestations, pathophysiological mechanisms and its latest research direction including microRNA-regulated networks, and potential therapeutic strategies of muscle wasting in heart failure. Our goal is to provide a basis for clinicians to further understand and treat the muscle wasting in heart failure patients.展开更多
Cancer cachexia(CC)is a complex metabolic syndrome that accelerates muscle wasting and affects up to 80%of patients with cancer;however,timely diagnostic methods and effective cures are lacking.Although a considerable...Cancer cachexia(CC)is a complex metabolic syndrome that accelerates muscle wasting and affects up to 80%of patients with cancer;however,timely diagnostic methods and effective cures are lacking.Although a considerable number of studies have focused on the mechanism of CC-induced muscle atrophy,few novel therapies have been applied in the last decade.In recent years,noncoding RNAs(ncRNAs)have attracted great attention as many differentially expressed ncRNAs in cancer cachectic muscles have been reported to participate in the inhibition of myogenesis and activation of proteolysis.In addition,extracellular vesicles(EVs),which function as ncRNA carriers in intercellular communication,are closely involved in changing ncRNA expression profiles in muscle and promoting the development of muscle wasting;thus,EV-related ncRNAs may represent potential therapeutic targets.This review comprehensively describes the process of ncRNA transmission through EVs and summarizes the pathways and targets of ncRNAs that lead to CC-induced muscle atrophy.展开更多
Background Recovery from sport injuries commonly involves a muscle disuse situation(i.e.,reduction in physical activity levels sometimes preceded by joint immobilization)with subsequent negative effects on muscle mass...Background Recovery from sport injuries commonly involves a muscle disuse situation(i.e.,reduction in physical activity levels sometimes preceded by joint immobilization)with subsequent negative effects on muscle mass and function.Purpose To summarize the current body of knowledge on the effectiveness of different physical strategies that are currently available to mitigate the negative effects of muscle disuse during recovery from sports injury.Methods A narrative review was conducted to summarize the information available on neuromuscular electrical stimulation(NMES),blood flow restriction(BFR)and vibration intervention.Results The concomitant application of BFR and low-intensity exercise has shown promising results in the prevention of disuse-induced muscle atrophy.Some benefits might also be obtained with BFR alone(i.e.,with no exercise),but evidence is still inconclusive.NMES,which can be applied both passively and synchronously with exercise,can also attenuate most of the negative changes associated with disuse periods.In turn,the mechanical stimulus elicited by vibration seems effec-tive to reduce the loss of bone mineral density that accompanies muscle disuse and could also provide some benefits at the muscle tissue level.Conclusions Different physical strategies are available to attenuate disuse-induced negative consequences during recovery from injury.These interventions can be applied passively,which makes them feasible during the first stages of the recovery.However,it would be advisable to apply these strategies in conjunction with low-intensity voluntary exercise as soon as this is feasible.展开更多
Introduction:Early childhood development(ECD)centres are important community hubs in South Africa and act as sites for community detection of childhood nutrition problems.This study aimed to assess the ability of trai...Introduction:Early childhood development(ECD)centres are important community hubs in South Africa and act as sites for community detection of childhood nutrition problems.This study aimed to assess the ability of trained ECD practitioners with optimal support to correctly classify the nutritional status of infants and young children at ECD centres in the Nelson Mandela Bay.Methods:A descriptive,cross-sectional study was used to collect data from 1645 infants and children at 88 ECD centres.Anthropometric measurements were taken by trained fieldworkers and growth monitoring and promotion infrastructure was audited at ECD centres.Results:Of the sample,4.4%(n=72)were underweight by weight for age Z-score(WAZ<-2)and 0.8%(n=13)were severely underweight(WAZ<-3).Results showed that 13.1%(n=214)were stunted by height for age Z-score(HAZ<-2)and 4.5%(n=74)were severely stunted(HAZ<-3).The prevalence of moderate acute malnutrition was 1.2%and severe acute malnutrition was 0.5%,while the prevalence of overweight was 9.2%and the prevalence of obesity was 4%.A significant level of agreement between the correct interpretation and the ECD practitioners'interpretation was observed across all the anthropometric indicators investigated.The true positive wasting cases had a mean mid-upper arm circumference(MUAC)of 14.6 cm,which may explain the high false negative rate found in terms of children identified with wasting,where ECD practitioners fail to use the weight for height Z-score(WHZ)interpretation for screening.Conclusion:By using ECD centres as hub to screen for malnutrition,it may contribute to the early identification of failure to thrive among young children.Although it was concerning that trained ECD practitioners are missing some children with an unacceptably high false negative rate,it may have been due to the fact that wasting in older children cannot be identified with MUAC alone and that accurate WFH plotting is needed.Onsite mentorship by governmental health workers may provide ECD practitioners with more confidence to screen children for growth failure based on regular WFH measurements.Moreover,ECD practitioners will be more confident to monitor the Road to Health booklets for missed vaccinations,vitamin A and deworming opportunities.展开更多
Chromium plays a vital role in stainless steel due to its ability to improve the corrosion resistance of the latter.However,the re-lease of chromium from stainless steel slag(SSS)during SSS stockpiling causes detrimen...Chromium plays a vital role in stainless steel due to its ability to improve the corrosion resistance of the latter.However,the re-lease of chromium from stainless steel slag(SSS)during SSS stockpiling causes detrimental environmental issues.To prevent chromium pollution,the effects of iron oxide on crystallization behavior and spatial distribution of spinel were investigated in this work.The results revealed that FeO was more conducive to the growth of spinels compared with Fe2O3 and Fe3O4.Spinels were found to be mainly distrib-uted at the top and bottom of slag.The amount of spinel phase at the bottom decreased with the increasing FeO content,while that at the top increased.The average particle size of spinel in the slag with 18wt%FeO content was 12.8μm.Meanwhile,no notable structural changes were observed with a further increase in FeO content.In other words,the spatial distribution of spinel changed when the content of iron oxide varied in the range of 8wt%to 18wt%.Finally,less spinel was found at the bottom of slag with a FeO content of 23wt%.展开更多
This work investigated the pyrolysis reaction of waste resin in a fluidized bed reactor.It was found that the pyrolysis-generated ash would adhere to the surface of ceramic particles,causing particle agglomeration and...This work investigated the pyrolysis reaction of waste resin in a fluidized bed reactor.It was found that the pyrolysis-generated ash would adhere to the surface of ceramic particles,causing particle agglomeration and defluidization.Adding kaolin could effectively inhibit the particle agglomeration during the fluidized pyrolysis reaction through physical isolation and chemical reaction.On the one hand,kaolin could form a coating layer on the surface of ceramic particles to prevent the adhesion of organic ash generated by the pyrolysis of resin.On the other hand,when a sufficient amount of kaolin(-0.2%(mass))was added,the activated kaolin could fully contact with the Na+ ions generated by the pyrolysis of resin and react to form a high-melting aluminosilicate mineral(nepheline),which could reduce the formation of low-melting-point sodium sulfate and thereby avoid the agglomeration of ceramic particles.展开更多
After the converter steelmaking process,a considerable number of ferroalloys are needed to remove dissolved oxygen from the molten steel,but it also forms a lot of oxide inclusions that cannot be completely removed.At...After the converter steelmaking process,a considerable number of ferroalloys are needed to remove dissolved oxygen from the molten steel,but it also forms a lot of oxide inclusions that cannot be completely removed.At the same time,it increases the carbon emis-sions in the steel production process.After years of research,our team have developed a series of clean deoxidation technologies,includ-ing carbon deoxidation,hydrogen deoxidation,and waste plastic deoxidation of molten steel to address the aforementioned issues.In this study,thermodynamic calculations and laboratory experiments were employed to verify that carbon and hydrogen can reduce the total oxygen content in the molten steel melt to below 5×10^(-6) and 10×10^(-6),respectively.An analysis of the deoxidation mechanisms and ef-fects of polyethylene and polypropylene was also conducted.In addition,the applications of carbon deoxidation technology in different steels with the hot-state experiment and industrial production were discussed carefully.The carbon deoxidation experimental results of different steels were as follows:(1)the oxygen content of bearing steel was effectively controlled at 6.3×10^(-6) and the inclusion number density was lowered by 74.73%compared to aluminum deoxidized bearing steel;(2)the oxygen content in gear steel was reduced to 7.7×10^(-6) and a 54.49%reduction of inclusion number density was achieved with almost no inclusions larger than 5μm from the average level of industry gear steels;(3)a total oxygen content of M2 high-speed steel was as low as 3.7×10^(-6).In industrial production practice,car-bon deoxidation technique was applied in the final deoxidation stage for non-aluminum deoxidized bearing steel,and it yielded excellent results that the oxygen content was reduced to below 8×10^(-6) and the oxide inclusions in the steel mainly consist of silicates,along with small amounts of spinel and calcium aluminate.展开更多
Porous materials present significant advantages for absorbing radioactive isotopes in nuclear waste streams.To improve absorption efficiency in nuclear waste treatment,a thorough understanding of the diffusion-advecti...Porous materials present significant advantages for absorbing radioactive isotopes in nuclear waste streams.To improve absorption efficiency in nuclear waste treatment,a thorough understanding of the diffusion-advection process within porous structures is essential for material design.In this study,we present advancements in the volumetric lattice Boltzmann method(VLBM)for modeling and simulating pore-scale diffusion-advection of radioactive isotopes within geopolymer porous structures.These structures are created using the phase field method(PFM)to precisely control pore architectures.In our VLBM approach,we introduce a concentration field of an isotope seamlessly coupled with the velocity field and solve it by the time evolution of its particle population function.To address the computational intensity inherent in the coupled lattice Boltzmann equations for velocity and concentration fields,we implement graphics processing unit(GPU)parallelization.Validation of the developed model involves examining the flow and diffusion fields in porous structures.Remarkably,good agreement is observed for both the velocity field from VLBM and multiphysics object-oriented simulation environment(MOOSE),and the concentration field from VLBM and the finite difference method(FDM).Furthermore,we investigate the effects of background flow,species diffusivity,and porosity on the diffusion-advection behavior by varying the background flow velocity,diffusion coefficient,and pore volume fraction,respectively.Notably,all three parameters exert an influence on the diffusion-advection process.Increased background flow and diffusivity markedly accelerate the process due to increased advection intensity and enhanced diffusion capability,respectively.Conversely,increasing the porosity has a less significant effect,causing a slight slowdown of the diffusion-advection process due to the expanded pore volume.This comprehensive parametric study provides valuable insights into the kinetics of isotope uptake in porous structures,facilitating the development of porous materials for nuclear waste treatment applications.展开更多
基金funded in part by the Center on Emerging and Zoonotic Infectious Diseases(CEZID)of the National Institutes of General Medical Sciences underaward number P20GM130448.
文摘Transmissible spongiform encephalopathies(TSEs)are a group of progressive and ultimately fatal neurologic diseases of man and animals,all resulting from the propagated misfolding of the host's normal cellular prion protein.These diseases can be spontaneous,heritable,anthropogenic/iatrogenic,or in some cases horizontally transmissible,and include such notable TSEs as bovine spongiform encephalopathy(BSE)of cattle and chronic wasting disease(CWD)of cervids.Although they are both unequivocally protein misfolding disorders,they differ markedly in their pathogenesis,transmissibility,and zoonotic potential.While the BSE epidemic has largely abated over the past three decades following global feed bans on ruminant meat and bone meal,CWD,which is readily transmitted through various forms of excreta,has rapidly expanded from its original endemic zone to encompass much of North America,along with recently identified foci in Scandinavia.Most importantly,although the classical form of BSE has proven transmissible to humans consuming contaminated beef or beef products,so far there have been no conclusive reports on the zoonotic transmission of cWD to humans.The underlying basis for these differences-whether host or agent directed-are not well understood,though may be due to inherent differences in the three-dimensional structure of the misfolded BSE or CWD prion proteins or the expression levels and tissue distribution of respective cellular prion proteins.With the uncontrolled geographic spread of CWD,it is imperative that we improve our understanding of the factors governing prion disease pathogenesis,transmission,and zoonotic potential.
文摘Muscle wasting is defined as the progressive and generalized loss of muscle mass. Muscle depletion is a common feature of chronic liver disease foundin approximately 40% of patients with cirrhosis. Its etiology is multifactorial subsequent to liver failure and its prevalence increases along with disease severity. Cross-sectional analytic morphometry using computed tomography(CT) scan or magnetic resonance imaging are considered by consensus the gold standards to assess muscle size in cirrhosis for research purposes because they are not biased by fluid accumulation. Several studies have assessed the impact of muscle wasting on overall survival of patients in the waiting list for liver transplantation and there is a general agreement that decreased muscle size assessed by CT scan is an independent predictor for mortality in cirrhosis. It has been proposed that the addition of cross-sectional muscle area into the Model for End-stage Liver Disease can increase its prognostic performance. Nevertheless, the use of CT scan in assessing muscle size is inappropriate for routine clinical practice and an alternative cost-effective, easy to use and accurate tool should be developed. In conclusion, muscle wasting has a detrimental impact on survival of patients with cirrhosis and, thus, it remains to be elucidated if nutritional interventions and exercise could improve muscle wasting and, subsequently, survival in this setting.
基金Supported by The research project is implemented within the framework of the Action of the Operational Program "Education and Lifelong Learning"(Action’s Beneficiary:General Secretariat for Research and Technology)cofinanced by the European Social Fund(ESF)the Greek State
文摘Rheumatoid arthritis(RA), the commonest inflammatory arthritis, is a debilitating disease leading to functional and social disability. In addition to the joints, RA affects several other tissues of the body including the muscle. RA patients have significantly less muscle mass compared to the general population. Several theories have been proposed to explain this. High grade inflammation, a central component in the pathophysiology of the disease, has long been proposed as the key driver of muscle wasting. More recent findings however, indicate that inflammation on its own cannot fully explain the high prevalence of muscle wasting in RA. Thus, thecontribution of other potential confounders, such as nutrition and physical activity, has also been studied. Results indicate that they play a significant role in muscle wasting in RA, but again neither of these factors seems to be able to fully explain the condition. Oxidative stress is one of the major mechanisms thought to contribute to the development and progression of RA but its potential contribution to muscle wasting in these patients has received limited attention. Oxidative stress has been shown to promote muscle wasting in healthy populations and people with several chronic conditions. Moreover, all of the aforementioned potential contributors to muscle wasting in RA(i.e., inflammation, nutrition, and physical activity) may promote pro- or antioxidative mechanisms. This review aims to highlight the importance of oxidative stress as a driving mechanism for muscle wasting in RA and discusses potential interventions that may promote muscle regeneration via reduction in oxidative stress.
文摘The coexistence of different water homeostasis abnormalities following neurosurgery represents a diagnostic and therapeutic challenge for intensive care units. This paper reports the case of a 13 year-old boy who underwent surgery for a suprasellar tumour and, immediately after surgery, developed a cerebral abscess, persistent diabetes insipidus (DI) as well as cerebral salt wasting syndrome (CSWS). The early onset of CSWS following DI has been associated with a poor prognosis and increased mortality. In cases in which these abnormalities coexist, the increased polyuria secondary to the rise in natriuresis associated with CSWS might be erroneously interpreted as a sign of poor control of the DI, thereby leading to therapeutic mistakes. Treatment basically consists of restoring electrolytes and the joint administration of desmopressin and fludrocortisone.
文摘AIM To identify patients with end-stage renal disease treated by peritoneal dialysis(PD) who had zero body fat(BF) as determined by analysis of body composition using anthropometric formulas estimating body water(V) and to compare nutritional parameters between these patients and PD patients whose BF was above zero.METHODS Body weight(W) consists of fat-free mass(FFM) andBF.Anthropometric formulas for calculating V allow the calculation of FFM as V/0.73,where 0.73 is the water fraction of FFM at normal hydration.Wasting from loss of BF has adverse survival outcomes in PD.Advanced wasting was defined as zero BF when V/0.73 is equal to or exceeds W.This study,which analyzed 439 PD patients at their first clearance study,used the Watson formulas estimating V to identify patients with V_(Watson)/0.73 ≥ W and compared their nutritional indices with those of PD patients with V_(Watson)/0.73 < W.RESULTS The study identified at the first clearance study two male patients with V_(Watson)/0.73 ≥ W among 439 patients on PD.Compared to 260 other male patients on PD,the two subjects with advanced wasting had exceptionally low body mass index and serum albumin concentration.The first of the two subjects also had very low values for serum creatinine concentration and total(in urine and spent peritoneal dialysate) creatinine excretion rate while the second subject had an elevated serum creatinine concentration and high creatinine excretion rate due,most probably,to non-compliance with the PD prescription.CONCLUSION Advanced wasting(zero BF) in PD patients,identified by the anthropometric formulas that estimate V,while rare,is associated with indices of poor somatic and visceral nutrition.
文摘The aim of the study is to monitor and assess landslide hazards by remote sensing data processing and GIS (Geographic Information Service) spatial analysis. Idukki district, the western Ghats of India was chosen as test area, because of frequent destructive mass wasting processes. Western Ghats is a prominent orographic feature that runs parallel to the south west coast of India. Predicting landslide hazard on a regional scale, namely the assessment of actual and potential mass movement over large area is carried out using Remote Sensing and GIS. A numerical weightage to the causative factors of slope instability such as slope, relative relief, aspect, curvature, drainage density, drainage frequency, land use, road buffer and drainage buffer are assigned as per earlier workers for the purpose of landslide susceptibility zonation. A high degree of match is found between observed and predicted landslide hazard by the procedure employed in the study.
文摘Protein energy wasting (PEW) is a major challenge in CKD. Objective: To assess PEW in predialysis patients on their first visit to a nephrologist. Methods: Three day dietary intake of 484 CKD stage 3 patients was taken. Appetite was assessed with ADAT. Patients were divided into groups based on appetite and BMI. Results: Male and female parameters are serum albumin 3.7 ± 0.84/3.68.8 ± 0.81 g/dL, total protein 7.02 ± 1.27/6.94 ± 1.26 g/dL, creatinine 4.68 ± 4.19/3.74 ± 3.36 mg% creatinine clearance 33.22 ± 30.48/37.55 ± 33.87 ml/minute, BMI 22.60 ± 4.29/23.43 ± 4.77kg/m2 energy/kg 16.97 ± 0.65/16.8 ± 0.64, protein g/kg 0.65 ± 0.28/0.64 ± 0.30, carbohydrate g/kg 2.98 ± 1.54/2.98 ± 0.1.36, fat g/kg 2.98 ± 0.23/2.79 ± 0.22, respectively. As appetite decreased, dietary protein and energy intake decreased significantly. Appetite in males and females: Average 14.46%, 4.13%, poor 9.7%, 18.18%, anorexic 13.2%, 7.4%. Income had strong correlation with BMI (p 0.000), dietary protein (p 0.000), energy (p 0.000) and carbohydrate (p 0.000). Appetite correlated with creatinine (p 0.019), dietary energy, protein, carbohydrate and fat (p 0.000) intake. BMI correlated (p 0.000) with fat, carbohydrate, energy and creatinine clearance. ANOVA showed significant difference within and between appetite groups in energy, protein, fat, carbohydrate, creatinine clearance (p 0.000) and serum albumin (p 0.025). There was significant difference in protein (p 0.026), energy intake (p 0.000) and creatinine clearance (p 0.038) within and between BMI groups. Based on income, there was significant difference among groups in BMI (p 0.000), energy (p 0.019), protein (p 0.031) and albumin (0.001).
文摘Background: The existence and prevalence of cerebral salt wasting and its differentiation from syndrome of inappropriate antidiuretic hormone have been controversial. This controversy stems from overlapping clinical and laboratory findings and an inability to assess the volume status of these patients. Objectives:To present a case of a cerebral salt wasting syndrome secondary to a bacterial mengitis and to emphasize the difficulty to assess the diagnosis. Case report: A 51-year-old male admitted to the ICU for a severe bacterial meningitis who developed, four days later, hyponatremia associated with hypovolemia due to a renal salt wasting. Clinical and biological parameters were collected;electrolytes balances and salt clearances were calculated to best investigate this hydroelectrolytic disorder. Patient's volume status and improvement after fluid and sodium replacement highly suggests the diagnosis of a cerebral salt wasting syndrome. Conclusion: A thorough analysis of this case showed that occurrence of hyponatremia and renal salt wasting after brain agression is not univocal underlying the fact that the diagnosis of cerebral salt wasting should be assessed only after a careful examination of the different determinants of the hydroelectrolytical balance.
文摘The purpose of the research was to obtain the mass wasting hazard map for the state of Vargas, central coast of Venezuela, using GIS technology. The work was developed through the heuristic method with the generation of thematic digital maps, univariate statistical treatment, weighting of each variable and quantifying the relationship of each parameter unit regarding mass wasting processes. The algorithm designed to perform map algebra was designed using the variables: surface geology, slope, slope orientation, terrain curvature, moisture topographic index, power index surface flow rate and capacity sediment transport and the rate normalized difference vegetation. The results show a distribution of landslide hazard with the highest values in the west central part of Vargas state, where the dominant lithology is incompetent, and combined with topographic elements, determining high instability, meanwhile the lower hazard areas were found in specific areas such as the middle watershed areas east of the state. The calibration of this model shows a reliability of 80%, so it is highly advisable to use the information generated in this work by governmental and non-governmental organizations in the planning, management and use of land.
文摘<strong>Background:</strong> Malnutrition is a strong predictor of prognosis in maintenance hemodialysis patients (MHD). We previously proposed a new and simple protein-energy wasting (PEW) score that appears to be useful for assessing the risk of mortality in patients on MHD. <strong>Objectives: </strong>In the present study, we evaluated the reliability of this PEW score as a predictor of hospitalization in Japanese patients on MHD. <strong>Methods:</strong> In this single-center, prospective cohort study conducted in Japan, PEW score was calculated for 180 MHD patients. PEW score ranged from 0 (best: S1) to 4 (worst: S4) and was calculated based on nutritional indicators including serum albumin, body mass index, serum creatinine level, and protein intake. The outcome was the number of hospitalizations during the 2-year study period. <strong>Results:</strong> Thirty-six patients were hospitalized during the study period. Kaplan-Meier curves showed there were fewer hospitalizations in the group with a PEW score of 0/1 than in the group with a score of 3/4. Multivariate analysis revealed a hazard ratio for hospitalization of 3.109 for S3/4 versus S0, 2.777 for S3/4 versus S1, and 2.048 for S3/4 versus S2.<strong> Conclusion:</strong> The new and simple PEW score is a useful predictor of hospitalization in MHD patients and is also useful for identifying subgroups of MHD patients with a high risk of mortality.
文摘Introduction: A higher risk of death is associated with wasting in children if it is not treated properly. The objective of this study was to investigate the ionic disorders observed in infants suffering from severe wasting at Yalgado Ouedraogo Teaching Hospital (YO-TH) and at Charles de Gaulle Pediatric Teaching Hospital (CDG-PTH) in Ouagadougou (Burkina Faso). Methods: This was a retrospective study with a descriptive and analytical aim over the period from January 1, 2016 to December 31, 2020. Results: It concerned infants aged 6 to 24 months hospitalized at YO-TH and at CDG-PTH from Ouagadougou. We included 271 infants. The mean age of the infants was 14.48 ± 5.44 months with 42.07% which was in the age range of [12 - 18] months. On admission to the hospital, the children had an average weight, height and BMI of 6.22 ± 1.32 kg, 0.73 ± 0.07 m and 11.67 ± 1.53 kg/m<sup>2</sup>. In urban areas 56.46% of children and the main reasons for consultation were fever (88.19%), vomiting (52.80%) and diarrhea (50.20%). Electrolyte disturbances in emaciated infants affected all 8 parameters of the blood ionogram. However, the major disorders were 65.68% hyponatremia, 55.35% hypobicarbonatemia, 41.33% hypoprotidemia and 32.47% hypokalemia in infants aged 6 to 24 months. We found an association between diarrhea and residence with hypokalemia (p = 0.0000) and hypochloremia (p = 0.010), respectively. Conclusion: Severe acute wasting in infants 6 to 24 months of age remains a concern in the hospital setting. The frequency of biochemical disturbances is also high.
文摘Research shows that workers drift from their contracted tasks to personal email,social networks and the far corners of the internet for anything between a few hours a week to a few hours a day.Six out of 10people admit they can’t get through the workday without checking their social media.
文摘Background Muscle wasting is a common clinical phenomenon that affects at least 20 percent of patients with heart failure. The exercise capacity of heart failure patients is limited; if left unchecked, which can form ca- chexia, seriously affecting the quality of life of patients with heart failure. This paper summarizes the clinical manifestations, pathophysiological mechanisms and its latest research direction including microRNA-regulated networks, and potential therapeutic strategies of muscle wasting in heart failure. Our goal is to provide a basis for clinicians to further understand and treat the muscle wasting in heart failure patients.
基金We gratefully acknowledge the financial support from the National Natural Science Foundation of China(Grant No.81972546)the National Training Programs of Innovation and Entrepreneurship for Undergraduates of China(Grant No.201910611653).
文摘Cancer cachexia(CC)is a complex metabolic syndrome that accelerates muscle wasting and affects up to 80%of patients with cancer;however,timely diagnostic methods and effective cures are lacking.Although a considerable number of studies have focused on the mechanism of CC-induced muscle atrophy,few novel therapies have been applied in the last decade.In recent years,noncoding RNAs(ncRNAs)have attracted great attention as many differentially expressed ncRNAs in cancer cachectic muscles have been reported to participate in the inhibition of myogenesis and activation of proteolysis.In addition,extracellular vesicles(EVs),which function as ncRNA carriers in intercellular communication,are closely involved in changing ncRNA expression profiles in muscle and promoting the development of muscle wasting;thus,EV-related ncRNAs may represent potential therapeutic targets.This review comprehensively describes the process of ncRNA transmission through EVs and summarizes the pathways and targets of ncRNAs that lead to CC-induced muscle atrophy.
基金supported by the University of Alcalá(contract number FPI2016 to Valenzuela)the Spanish Ministry of Education,Culture and Sport(contract number FPU14/03435 to Morales)the Spanish Ministry of Economy and Competitiveness(Fondo de Investigaciones Sanitarias and Fondos FEDER,grant numbers PI15/00558 and PI18/00139 to Lucia).
文摘Background Recovery from sport injuries commonly involves a muscle disuse situation(i.e.,reduction in physical activity levels sometimes preceded by joint immobilization)with subsequent negative effects on muscle mass and function.Purpose To summarize the current body of knowledge on the effectiveness of different physical strategies that are currently available to mitigate the negative effects of muscle disuse during recovery from sports injury.Methods A narrative review was conducted to summarize the information available on neuromuscular electrical stimulation(NMES),blood flow restriction(BFR)and vibration intervention.Results The concomitant application of BFR and low-intensity exercise has shown promising results in the prevention of disuse-induced muscle atrophy.Some benefits might also be obtained with BFR alone(i.e.,with no exercise),but evidence is still inconclusive.NMES,which can be applied both passively and synchronously with exercise,can also attenuate most of the negative changes associated with disuse periods.In turn,the mechanical stimulus elicited by vibration seems effec-tive to reduce the loss of bone mineral density that accompanies muscle disuse and could also provide some benefits at the muscle tissue level.Conclusions Different physical strategies are available to attenuate disuse-induced negative consequences during recovery from injury.These interventions can be applied passively,which makes them feasible during the first stages of the recovery.However,it would be advisable to apply these strategies in conjunction with low-intensity voluntary exercise as soon as this is feasible.
基金Nelson Mandela University,London Metropolitan University and UNICEF。
文摘Introduction:Early childhood development(ECD)centres are important community hubs in South Africa and act as sites for community detection of childhood nutrition problems.This study aimed to assess the ability of trained ECD practitioners with optimal support to correctly classify the nutritional status of infants and young children at ECD centres in the Nelson Mandela Bay.Methods:A descriptive,cross-sectional study was used to collect data from 1645 infants and children at 88 ECD centres.Anthropometric measurements were taken by trained fieldworkers and growth monitoring and promotion infrastructure was audited at ECD centres.Results:Of the sample,4.4%(n=72)were underweight by weight for age Z-score(WAZ<-2)and 0.8%(n=13)were severely underweight(WAZ<-3).Results showed that 13.1%(n=214)were stunted by height for age Z-score(HAZ<-2)and 4.5%(n=74)were severely stunted(HAZ<-3).The prevalence of moderate acute malnutrition was 1.2%and severe acute malnutrition was 0.5%,while the prevalence of overweight was 9.2%and the prevalence of obesity was 4%.A significant level of agreement between the correct interpretation and the ECD practitioners'interpretation was observed across all the anthropometric indicators investigated.The true positive wasting cases had a mean mid-upper arm circumference(MUAC)of 14.6 cm,which may explain the high false negative rate found in terms of children identified with wasting,where ECD practitioners fail to use the weight for height Z-score(WHZ)interpretation for screening.Conclusion:By using ECD centres as hub to screen for malnutrition,it may contribute to the early identification of failure to thrive among young children.Although it was concerning that trained ECD practitioners are missing some children with an unacceptably high false negative rate,it may have been due to the fact that wasting in older children cannot be identified with MUAC alone and that accurate WFH plotting is needed.Onsite mentorship by governmental health workers may provide ECD practitioners with more confidence to screen children for growth failure based on regular WFH measurements.Moreover,ECD practitioners will be more confident to monitor the Road to Health booklets for missed vaccinations,vitamin A and deworming opportunities.
基金the National Natural Science Foundation of China(Nos.52074078 and 52374327)the Applied Fundamental Research Program of Liaoning Province(No.2023JH2/101600002)+2 种基金the Shenyang Young Middle-Aged Scientific and Technological Innovation Talent Support Program(No.RC220491)the Liaoning Province Steel Industry-University-Research Innovation Alliance Cooperation Project of Bensteel Group(No.KJBLM202202)the Fundamental Research Funds for the Central Universities(Nos.N2201023 and N2325009).
文摘Chromium plays a vital role in stainless steel due to its ability to improve the corrosion resistance of the latter.However,the re-lease of chromium from stainless steel slag(SSS)during SSS stockpiling causes detrimental environmental issues.To prevent chromium pollution,the effects of iron oxide on crystallization behavior and spatial distribution of spinel were investigated in this work.The results revealed that FeO was more conducive to the growth of spinels compared with Fe2O3 and Fe3O4.Spinels were found to be mainly distrib-uted at the top and bottom of slag.The amount of spinel phase at the bottom decreased with the increasing FeO content,while that at the top increased.The average particle size of spinel in the slag with 18wt%FeO content was 12.8μm.Meanwhile,no notable structural changes were observed with a further increase in FeO content.In other words,the spatial distribution of spinel changed when the content of iron oxide varied in the range of 8wt%to 18wt%.Finally,less spinel was found at the bottom of slag with a FeO content of 23wt%.
基金support and encouragement of the Joint Funds of the National Natural Science Foundation of China(No.U21B2095)the Major Research Project of National Natural Science Foundation of China(No.91834303).
文摘This work investigated the pyrolysis reaction of waste resin in a fluidized bed reactor.It was found that the pyrolysis-generated ash would adhere to the surface of ceramic particles,causing particle agglomeration and defluidization.Adding kaolin could effectively inhibit the particle agglomeration during the fluidized pyrolysis reaction through physical isolation and chemical reaction.On the one hand,kaolin could form a coating layer on the surface of ceramic particles to prevent the adhesion of organic ash generated by the pyrolysis of resin.On the other hand,when a sufficient amount of kaolin(-0.2%(mass))was added,the activated kaolin could fully contact with the Na+ ions generated by the pyrolysis of resin and react to form a high-melting aluminosilicate mineral(nepheline),which could reduce the formation of low-melting-point sodium sulfate and thereby avoid the agglomeration of ceramic particles.
基金supported by the National Natural Science Foundation of China(No.52174297).
文摘After the converter steelmaking process,a considerable number of ferroalloys are needed to remove dissolved oxygen from the molten steel,but it also forms a lot of oxide inclusions that cannot be completely removed.At the same time,it increases the carbon emis-sions in the steel production process.After years of research,our team have developed a series of clean deoxidation technologies,includ-ing carbon deoxidation,hydrogen deoxidation,and waste plastic deoxidation of molten steel to address the aforementioned issues.In this study,thermodynamic calculations and laboratory experiments were employed to verify that carbon and hydrogen can reduce the total oxygen content in the molten steel melt to below 5×10^(-6) and 10×10^(-6),respectively.An analysis of the deoxidation mechanisms and ef-fects of polyethylene and polypropylene was also conducted.In addition,the applications of carbon deoxidation technology in different steels with the hot-state experiment and industrial production were discussed carefully.The carbon deoxidation experimental results of different steels were as follows:(1)the oxygen content of bearing steel was effectively controlled at 6.3×10^(-6) and the inclusion number density was lowered by 74.73%compared to aluminum deoxidized bearing steel;(2)the oxygen content in gear steel was reduced to 7.7×10^(-6) and a 54.49%reduction of inclusion number density was achieved with almost no inclusions larger than 5μm from the average level of industry gear steels;(3)a total oxygen content of M2 high-speed steel was as low as 3.7×10^(-6).In industrial production practice,car-bon deoxidation technique was applied in the final deoxidation stage for non-aluminum deoxidized bearing steel,and it yielded excellent results that the oxygen content was reduced to below 8×10^(-6) and the oxide inclusions in the steel mainly consist of silicates,along with small amounts of spinel and calcium aluminate.
基金supported as part of the Center for Hierarchical Waste Form Materials,an Energy Frontier Research Center funded by the U.S.Department of Energy,Office of Science,Basic Energy Sciences under Award No.DE-SC0016574.
文摘Porous materials present significant advantages for absorbing radioactive isotopes in nuclear waste streams.To improve absorption efficiency in nuclear waste treatment,a thorough understanding of the diffusion-advection process within porous structures is essential for material design.In this study,we present advancements in the volumetric lattice Boltzmann method(VLBM)for modeling and simulating pore-scale diffusion-advection of radioactive isotopes within geopolymer porous structures.These structures are created using the phase field method(PFM)to precisely control pore architectures.In our VLBM approach,we introduce a concentration field of an isotope seamlessly coupled with the velocity field and solve it by the time evolution of its particle population function.To address the computational intensity inherent in the coupled lattice Boltzmann equations for velocity and concentration fields,we implement graphics processing unit(GPU)parallelization.Validation of the developed model involves examining the flow and diffusion fields in porous structures.Remarkably,good agreement is observed for both the velocity field from VLBM and multiphysics object-oriented simulation environment(MOOSE),and the concentration field from VLBM and the finite difference method(FDM).Furthermore,we investigate the effects of background flow,species diffusivity,and porosity on the diffusion-advection behavior by varying the background flow velocity,diffusion coefficient,and pore volume fraction,respectively.Notably,all three parameters exert an influence on the diffusion-advection process.Increased background flow and diffusivity markedly accelerate the process due to increased advection intensity and enhanced diffusion capability,respectively.Conversely,increasing the porosity has a less significant effect,causing a slight slowdown of the diffusion-advection process due to the expanded pore volume.This comprehensive parametric study provides valuable insights into the kinetics of isotope uptake in porous structures,facilitating the development of porous materials for nuclear waste treatment applications.