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Nanoparticles synthesis is an evergreen research field of 21st century in which the connotation of the biomediated experimental process is highly imperative. Biomediated silver nanoparticles were synthesized with the aid of an eco-friendly biomaterial, namely, aqueous Azadirachta indica extract. The effect of pH and temperature on the formation of silver nanoparticles was analyzed. Formation of the silver nanoparticles was verified by surface plasmon spectra using a UV−vis spectrophotometer. Morphology and crystalline structure of the prepared silver nanoparticles were characterized by TEM and XRD techniques, respectively. Furthermore, the biomediated silver nanoparticles without any surface modification were used for the heavy metal ion sensors in aqueous media. The prepared silver nanoparticles were successful in detecting even the minimal amount of heavy metal copper(II) ion and exhibited excellent specific metal ion selectivity.

Background and Purpose— The theory of cognitive reserve (CR) was introduced to account for individual differences in the clinical manifestation of neuropathology. This study investigated whether CR has a modulating effect on cognitive impairment and recovery after stroke. Methods— This study is an interim analysis of the Korean Stroke Cohort for Functioning and Rehabilitation. A total of 7459 patients with first-ever stroke were included for analysis. Education, occupation, and composite CR scores derived from those 2 variables were used as CR proxies. Scores from the Korean version of the Mini-Mental State Examination analyzed for 30 months after stroke onset were analyzed. Results— Lower CR increased the risk of cognitive impairment after stroke. The odds ratio was 1.89 (95% CI, 1.64–2.19) in patients with secondary education and 2.42 (95% CI, 2.03–2.90) in patients with primary education compared with patients with higher education. The odds ratio was 1.48 (95% CI, 1.23–1.98) in patients with a skilled manual occupation and 2.01 (95% CI, 1.42–2.83) in patients with a nonskilled manual occupation compared with patients with a managerial or professional occupation. In the multilevel model analysis, the Korean version of the Mini-Mental State Examination total score increased during the first 3 months (1.93 points per month) and then plateaued (0.02 point per month). The slopes were moderated by the level of education, occupation, and composite CR score: the higher the level of education, occupation, or CR score, the faster the recovery. In the older adult group, the Korean version of the Mini-Mental State Examination scores showed a long-term decline that was moderated by education level. Conclusions— Education and occupation can buffer an individual against cognitive impairment caused by stroke and promote rapid cognitive recovery early after stroke. In addition, higher education minimizes long-term cognitive decline after stroke, especially in older patients. Clinical Trial Registration— URL: https://www.clinicaltrials.gov . Unique identifier: NCT03402451.

Assessment of functional independence and residual disability is very important for measuring treatment outcome after stroke. The modified Rankin Scale (mRS) and the modified Barthel Index (MBI) are commonly used scales to measure disability or dependence in activities of daily living (ADL) of stroke survivors. Lack of consensus regarding MBI score categories has caused confusion in interpreting stroke outcomes. The purpose of this study was to identify the optimal corresponding MBI and modified Rankin scale (mRS) grades for categorization of MBI. The Korean versions of the MBI (K-MBI) and mRS were collected from 5,759 stroke patients at 3 months after onset of stroke. The sensitivity and specificity were calculated at K-MBI score cutoffs for each mRS grade to obtain optimally corresponding K-MBI scores and mRS grades. We also plotted receiver operating characteristic (ROC) curves of sensitivity and specificity and determined the area under the curve (AUC). The K-MBI cutoff points with the highest sum of sensitivity and specificity were 100 (sensitivity 0.940; specificity 0.612), 98 (sensitivity 0.904; specificity 0.838), 94 (sensitivity 0.885; PLOS ONE | https://doi.

Three-dimensional (3D) copper–cobalt (Cu–Co)/reduced graphene oxide (rGO) hierarchical architectures are electrochemically deposited over a pencil graphite electrode (PGE), and the modified PGE is directly exploited as a binder-free and disposable electrode for high performance nonenzymatic glucose sensors. The morphological features substantiate that the Cu–Co nanostructures display a 3D, open, porous, interconnected network architecture, in which the rGO layers are tightly pinned among the nanofeelers. Owing to the benefits of dendrite architectures and optimized composition, Cu–Co/rGO/PGE demonstrates better glucose oxidation behavior under alkaline conditions. Being a nonenzymatic glucose sensor, Cu–Co/rGO/PGE demonstrates excellent gluose detection properties with considerable chloride poisoning resistance. The excellent analytical performance of Cu–Co/rGO/PGE comprehends its application in human serum samples. Thus, this report paves constructive opportunities for the development of disposable, environmentally benign, binder-free, cost-efficient, and scalable 3D electrodes, which may be beneficial for the development of economically viable nonenzymatic glucose sensor devices.

Uniform sized Ni-Co alloy nanoparticles were effectively confined over the active channels of mesoporous silica nanoparticles (MSN) using a simple chemical reduction method, and the resultant nanostructures exhibited a spherical configuration with a mean diameter of 5 nm. The face-centered cubic (fcc) crystalline structure of Ni and Ni-Co alloy nanoparticles and the amorphous structure of MSN matrix were identified from the diffraction patterns. The MSN supported catalysts were exploited as electrochemical probes for the detection of glucose, and the controlled morphology, smaller particle size, uniform dispersion and active surface of the Ni-Co alloy nanoparticles improved the excellent electrocatalytic activity of MSN/Ni-Co toward the electrooxidation of glucose. The MSN/Ni-Co nanocomposite exhibited good analytical performance for glucose detection, with a linear response ranging from 0.001 to 5.0 mM, a low detection limit of 0.39 mM and a high sensitivity of 536.62 mA mM À1 cm À2 . The results of the performed experiments also demonstrated the good reproducibility, long-term stability and high selectivity of the fabricated sensors without the influence of interference from other oxidizable species, which may represent a technically sound and economical new avenue in nonenzymatic glucose sensor applications.

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