Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed

© Hindawi Publishing Corp. DIFFUSIVE INSTABILITY IN A PREY-PREDATOR SYSTEM WITH TIME-DEPENDENT DIFFUSIVITY

An ecological model for prey-predator planktonic species has been considered, in which the growth of prey has been assumed to follow a Holling type II function. The model consists of two reaction-diffusion equations and we extend it to timevarying diffusivity for plankton population. A comparative study of local stability in case of constant diffusivity and time varying diffusivity has been performed. It has been found that the system would be more stable with time varying diffusivity depending upon the values of system parameter. 2000 Mathematics Subject Classification: 37G15. 1. Introduction. In 1952, Turing [10] proposed a diffusion-reaction theory of morphogenesis on the basis of well-known laws of physical chemistry. This concept has been extended to develop the theory of biological pattern formation. In an ecological context, Segel and Jackson [8] were the first to apply Turing’s model to predator-prey system. Since then, diffusive instabilit

Frontal osteomyelitis presenting as upper eyelid ectropion: A cautionary tale

Frontal osteomyelitis is a rare clinical entity that can occur as sequelae to frontal sinusitis, head trauma, as a postoperative complication following sinus surgery or due to haematogenous spread. It usually presents with a soft, fluctuant forehead swelling with pain and fever. Cicatricial ectropion is an extremely rare feature of frontal osteomyelitis. We present a young male patient presenting with cicatricial ectropion that occurred as the sole manifestation of an underlying frontal osteomyelitis. Extensive Medline search did not find any such reported case. We feel that frontal osteomyelitis should be kept in mind as a possible etiology when considering the differential diagnosis of cicatricial ectropion. Keywords: Osteomyelitis, Frontal sinusitis, Cicatricial ectropio

A nonlinear two-species oscillatory system: bifurcation and stability analysis

The present paper dealing with the nonlinear bifurcation analysis of two-species oscillatory system consists of three parts. The first part deals with Hopf-bifurcation and limit cycle analysis of the homogeneous system. The second consists of travelling wave train solution and its linear stability analysis of the system in presence of diffusion. The last deals with an oscillatory chemical system as an illustrative example

Effect of coal properties on scaffold formation in rotary kilns

The effect of fuel properties on ash deposition behaviour in a coal fired Rotary kiln, used for preparing iron rich pellets from virgin iron ore, was examined using simulated combustion conditions combined with a range of analytical techniques. A new index based on ash melting during thermo-mechanical analysis of coal ash is developed to predict ash deposition potential in a Rotary kiln, and related to ash deposition trend near the kiln entrance. Iron dust was found to consist of mainly hematite. Iron dust presence in coal increases ash agglomeration tendency such that agglomeration intensity increases with increasing concentration of iron dust. The study also established that intensity of iron dust impact is influenced by parent coal chemistry such that iron and calcium rich coals displayed greater intensity of iron dust impact. It seems external iron presence has a stronger effect on ash agglomeration compared to inherent coal iron minerals as confirmed by TMA index and ash agglomerate plot. The interfacial examination of iron dust and ash particles did not show any apparent evidence of chemical interactions which implies that iron dust mainly participated physically for the evolution of agglomerate at least under tested conditions. This suggests that in Rotary kiln, inertial impaction of iron dust may be determining intensity of deposit formation. Increasing kaolinite concentration in coal did not show any apparent change on the agglomeration tendency for low to medium slagging coals. It is possible that due to smaller particle size and lower density, their contribution to possible inertial impaction may be not significant. The study further highlighted that increase in mullite presence in high slagging coals mainly seems to be attributed to addition of external kaolinite in specimens. Like iron dust, kaolinite particles did not appear to show any chemical interaction with coal ash particles, even though occurs as mullite in the agglomerate. The interfacial studies supported the ash deposition prediction based on TMA index such that coals with high TMA index displayed high agglomeration index with exception of kaolinite rich coals.The study suggests that physical properties of coal minerals particularly iron bearing phases in coals may have strong effect on the growth of agglomeration. Therefore, future studies may focus on establishing the effect of physical properties of additive as well as variation of coal mineral chemistry with coal grain size