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The release of mercury into the environment has adverse effects on humans and aquatic species, even at very low concentrations. Pyrene and its derivatives have interesting fluorescence properties that can be utilized for mercury (Hg2+) ion sensing. Herein, we reported the highly selective pyrene-functionalized silica nanoparticles (Pyr-NH@SiO2 NPs) for chemosensing mercury (Hg2+) ions in a seawater sample. The Pyr-NH@SiO2 NPs were synthesized via a two-step protocol. First, a modified Stöber method was adopted to generate amino-functionalized silica nanoparticles (NH2@SiO2 NPs). Second, 1-pyrenecarboxylic acid was coupled to NH2@SiO2 NPs using a peptide coupling reaction. As-synthesized NH2@SiO2 NPs and Pyr-NH@SiO2 NPs were thoroughly investigated by 1H-NMR, FTIR, XRD, FESEM, EDS, TGA, and BET surface area analysis. The fluorescent properties were examined in deionized water under UV-light illumination. Finally, the developed Pyr-NH@SiO2 NPs were tested as a chemosensor for Hg2+ ions detection in a broad concentration range (0–50 ppm) via photoluminescence (PL) spectroscopy. The chemosensor can selectively detect Hg2+ ions in the presence of ubiquitous ions (Na+, K+, Ca2+, Mg2+, Ba2+, Ag+, and seawater samples). The quenching of fluorescence properties with Hg2+ ions (LOD: 10 ppb) indicates that Pyr-NH@SiO2 NPs can be effectively utilized as a promising chemosensor for mercury ion detection in seawater environments. [ABSTRACT FROM AUTHOR]

Objective: This study was planned to evaluate the role of body painting in short-term retention of knowledge and to assess students' perception of this activity in a public and private medical college. Methods: This interventional study was conducted in a private and public medical college in the month of September and October 2023. The students of MBBS 1st year from the 2 colleges were invited to participate in the study and those who volunteered were randomly divided by the balloting method into 2 equal groups: control and intervention. The control group was given a traditional lecture with the help of a Power point presentation, on the course and markings of the nerves and vessels of the hand and forearm. The intervention group was given an interactive body painting demonstration, with hands-on practice of painting the same vessels and nerves on each other. At the end of these sessions, the students attempted a multiple-choice-question paper and the results were compared using SPSS version 21.00. A questionnaire was also filled by the intervention group to provide the students' perception of the activity. Results: There was no significant difference between the mean multiple-choice-question scores of the control and intervention group. More than 85% of the students from both the colleges strongly agreed that the session was enjoyable and interesting and also 80% and beyond of students also believed that the exercise would help them to retain knowledge. Conclusion: The study concluded that there was a negligible difference in knowledge retention between the intervention group and the control group. However, the results of the questionnaire strongly suggested the use of the body painting technique in anatomy curricular teaching as it has proven to stimulate knowledge retention by enhancing students' interest, active participation and peer learning. [ABSTRACT FROM AUTHOR]

Dopamine (DA) is a neurotransmitter that plays a pivotal role in the brain’s proper functioning and several other physiological processes. Herein, we demonstrate the miniaturized electrochemical sensor for detecting DA using hafnium metal-organic framework (Hf-MOF) derived new nanocomposite of hafnium and cobalt oxides (HfO2-CoO). Calcination of Hf-MOF coated with cobalt acetylacetonate complex [(Co(acac)2] yield HfO2-CoO nanoparticles supported over in situ generated graphitic carbon. The excellent adsorption capabilities of HfO2 and highly catalytic CoO activity make this bimetallic HfO2-CoO nanocomposite to display a stable response over a wide linear concentration range when used as electrode material in the electrochemical DA sensing process. Moreover, the computational study also proves that CoO improves the chemisorption properties of HfO2 for DA. Electrochemical studies are performed through cyclic voltammetry (CV), linear sweep voltammetry (LSV), and differential pulse voltammetry (DPV). For the case of LSV, the HfO2-CoO nanocomposite modified glassy carbon electrode (HfO2-CoO/GCE) exhibit a linear response to DA concentration ranging from 0.25 to 3.15 mM. However, with DPV HfO2-CoO/GCE electrode has displayed a linear range of 10–190 μM and a detection limit of 1.8 μM is achieved. The electrode has also shown excellent stability, and only 19 % loss in its initial current response is observed over 150 days of specific interval testing. The HfO2-CoO/GCE nanocomposite electrode, due to its unique feature of stability, selectivity, and sensitivity, has a good potential for use as an analytical tool for non-enzymatic sensing of DA and other neurotransmitters in the human fluid. [ABSTRACT FROM AUTHOR]

Investigating novel materials with controlled morphology for solar‐driven conversions is the foremost research emphasis in applied sciences. In continuation of those efforts, we report the unique synthesis of a novel trimetallic β‐Cu2V2O7/Zn2V2O6 (CZVO) hybrid with controlled morphology. The trimetallic CZVO demonstrates a bifunctional, non‐sacrificial photoresponse in the cases of 1) photocatalytic degradation using methylene blue (MB) as a model dye; and 2) photoelectrochemical (PEC) water oxidation. The X‐ray photoelectron spectroscopy (XPS) analysis of CZVO confirmed Type‐(I) heterojunction formation between β‐Cu2V2O7 (CVO) and Zn2V2O6 (ZVO). After visible light exposure (65 min), CZVO‐opt (1 wt% CVO: 5 wt% ZVO) demonstrated the highest photodegradation, while the CZVO‐opt photoanode delivered the highest photocurrent density (Iph) of 1.78 mA cm−2 at 1.23 VRHE, almost 3.11 and 1.55 times more than CVO (Iph = 0.57 mA cm−2) and ZVO (Iph = 1.15 mA cm−2) photoanodes, respectively. The CZVO‐opt photoanode harvested the most solar energy in terms of incident photon to current conversion efficiency (IPCE320 nm = 37.93%). The significant improvement in the CZVO‐opt performance can be attributed to the firm contact and uniform distribution of ZVO NPs over CVO interlayered nanosheets, which leads to adequate solar absorption and facile charge transport through a Type‐(I) heterojunction with suppresses charge recombination. [ABSTRACT FROM AUTHOR]

Objective: Objective of the study were to evaluate dimensions of both lobes and calculation of thyroid volume by using ultrasonography (USG) and to compare these parameters between pregnant and non-pregnant in Karachi, Pakistan. Methodology: It was a clinical cross-sectional study that was conducted at Gynae OPD and Radiology Department, Karachi from October 2016 to December 2018 through consecutive sampling. The study volunteers of reproductive age (14 - 45 years) were included and divided into two groups (pregnant and non-pregnant women). The dimensions of each lobe and calculation of thyroid volume were taken into the account through their standard protocol after following inclusion and exclusion criteria. Results: The comparisons were made on thyroid gland dimensions, ultrasound outcomes of right and left lobe length, width, depth and volume of thyroid gland. In pregnant women, right lobe length was 2.91 ± 1.05, width was 1.54 ± 0.41 and depth was 2.31 ± 1.41 whereas in non-pregnant women mean right lobe length was 2.50 ± 0.97, width was 1.34 ± 0.51 and depth was 1.68 ± 0.98. The mean difference was considered statistically significant in pregnant women with p-value (< 0.01). In pregnant women thyroid volume was 7.02 ± 3.21 whereas in non-pregnant, it was 5.58 ± 2.41 which was significantly increased in pregnant women with p-value (< 0.01). Conclusion: Therefore, our study concludes that, in our population at least half of the apparently healthy pregnant females do have some degree of iodine deficiency. The volume of the gland is increased during pregnancy, suggesting iodine deficiency. [ABSTRACT FROM AUTHOR]

Cost‐effective separation of oil and immiscible organic contaminants from water has become an urgent challenge to protect aquatic and human life from devastating effects. Therefore, it has become imperative to develop super‐selective materials for efficiently separating oil from water. In this work, a superhydrophobic surface has been formed that consists of a silane@polystyrene‐coated polypropylene fibrous network (silane@PS‐PPF) for efficient separation of accidentally spilled oil from water. The superhydrophobic PPFs were designed by a simple, cost‐effective two‐step process that includes photochemically controlled polymerization of styrene and subsequent dip coating in octadecyltrichlorosilane solution. The hydrophobic surface (CA=129°±4°) of the PS coated PPF after treating with silane was turned into a superhydrophobic body (CA=161°±2°). The achieved silane@PS‐PPF fibrous network selectively allowed the fast permeation of the oils and non‐polar organic liquids by altogether rejecting water during operation. The separation efficiency for various oils from the contaminated water was 96 to 99%, with a high flux in the range of 7606±312 L m−2h−1 to 9870±151 L m−2h−1. Apart from being used as a filter, the silane@PS‐PPF was also used as an oil absorber and has shown an absorption capacity in the range of 1185 to 1535% for various oils. We anticipate that the developed silane@PS‐PPF, due to its facile synthetic route, cost‐effectiveness, and high performance, can be effectively used in oily wastewater treatment and clean‐up of large oil spills from water. [ABSTRACT FROM AUTHOR]