Mechanical performance of dense-graded asphalt mixture incorporating steel fiber

Dense graded asphalt is usually used for highways, main roads, industrial and distributor roads due to their densely packed constitution. In order to improve more on its durability, stability and service life various additives are introduced and among them are steel fibers. Steel fiber has been reported that it increases the mechanical performance of asphalt mix. This paper reports on a comprehensive study on the mechanical properties of dense-graded asphalt AC10 incorporating steel fibers. Mechanical properties studied include abrasion resistance, stability, density, stiffness, resilient modulus and dynamic creep of asphalt mixtures. The tests carried out are Abrasion test, Marshall Stability, resilient modulus and dynamic creep. Steel fiber content used was 0%, 0.2%, 0.4% and 0.6% of the asphalt mixtures. The laboratory results showed that steel fiber addition into DGA AC10, improve all the mechanical properties covered in this investigation except the stiffness. Although the addition of steel fiber reduces stiffness properties that makes it revealing to the deflection, the modified samples still shows improvement in abrasion, stability, density, resilient modulus and dynamic creep

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

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

Background Disorders 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. Methods We 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. Findings Globally, 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. Interpretation As 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. Funding Bill & Melinda Gates Foundation

A smart low molecular weight gelator for the triple detection of copper (II), mercury (II), and cyanide ions in water resources

Novel supramolecular gelators based on quinoline-indolin-2-one structure were synthesized. These gelators formed stable organogels in a mixture of DMSO/H2O (1:1). The scanning electron microscopy (SEM), IR and NMR spectroscopies, and rheological measurements were used to study the properties of the gels. Among the synthesized compounds, G2 was chosen as the best gelator and utilized as a naked eye chemosensor for the selective detection of Cu2+ and Hg2+ ions alongside and CN- ion as toxic and hazardous materials. The gelator G2 was selectively transformed into a sol state in the presence of Cu2+ ion alongside with a vivid change of color from orange to cherry red. Hg2+ ion showed a notable change in color from orange to brick red, but the gel state remained intact. The detection limit for the gelator G2 toward Cu(2+)and Hg2+ were 7.25 x 10(-6) mol. L-1 and 4.80 x 10(-6) mol. L-1 respectively. All the tested anions had no distinct effect on the gel state and/or the color of G2, while, in the presence of CN-, although the gel state was again unchanged a drastic color change from orange to dark purple was observed. The detection limit for G2 toward CN- was 1.36 x 10(-4) mol. L-1. The gelator G2 also operated simultaneously the roles of INH and OR gates in which water, Hg2+, Cu2+ ions are inputs, and the gel state and absorbance around 600 nm (color change) are outputs

Synthesis of tris-(azacrown) ethers for carboxylic acid recognition

The synergistic enhancement of metal ion extraction by azacrown ethers in the presence of carboxylic acids has been attributed to a ligand assembly effect in which these two ligands form a complex, facilitated by proton transfer, prior to complexation of the metal ion. In order to investigate the first steps in this multi-component complexation procedure, six tris-(azacrown) ethers were synthesised in high yields and their ability to complex mono- and tri-carboxylic acids was investigated by 1H NMR in methanol-d4. All six compounds bound to benzoic acid with 1:3 host-guest stoichiometry and four of them bound tricarboxylic acids with 1:1 host-guest stoichiometry, providing good support for the proposed first step in the ligand assembly effect

Approaches to the Construction of Substituted 4-Amino-1<i>H</i>-pyrrol-2(5<i>H</i>)-ones

Fully substituted 4-aminopyrrolones are easily accessed via simple routes starting from imines, ketones, or α-bromophenyl acetonitriles. Imines were reacted with KCN/NH₄Cl in aqueous ethanol to produce α-arylamino benzyl cyanides. On the other hand, ketones were transformed to the desired α-amino nitriles using a modified Strecker reaction. Then, α-amino nitrile precursors were allowed to react with a suitable acyl halide to produce the corresponding amides. Further treatment of these amides with ethanolic KOH converted them to highly substituted 4-amino-1<i>H</i>-pyrrol-2­(5<i>H</i>)-one derivatives in moderate to excellent yields