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This study aims to assess ecological risks from heavy metal atmospheric deposition in the Indus River at Kotri Barrage, Sindh, Pakistan. Monitoring occurred at four locations, yielding 40 air samples analyzed for heavy metals via Triple Quadrupole Inductively Coupled Plasma Mass Spectrometry (TQ-ICP-MS). Pollution indicators, including Contaminant Factor (CF), Degree of Contamination (CD), Geo-accumulation Index (Igeo), Enrichment Factor (EF), Pollution Load Index (PLI), Potential Ecological Risk Index (PERI), and Nemerow Integrated Pollution Index (NIPI), quantified contaminant levels. Air monitoring revealed PM2.5 concentrations exceeding regulatory guidelines at all four sites. Heavy metal mean concentrations ranked as follows: Fe > Cr > Pb > Mn > As > Cu > Ni > Cd > Mo > Co, and deposition fluxes followed this order: Fe > Pb > Cr > Mn > As > Cu > Ni > Cd > Mo > Co. Pollution indices indicated moderate to extreme pollution for Fe, Cr, Cd at all sites, and Pb at site D. Emissions from a nearby coal-fired power plant and vehicular sources were identified as primary contributors to high heavy metal deposition. The Ecological Risk Index ranged from 150 to 600, signifying substantial ecological risk linked to Cd. These findings offer crucial insights for governmental agencies and policymakers to address pollution issues arising from heavy metal atmospheric deposition in the Indus River near Kotri Barrage. [ABSTRACT FROM AUTHOR]

Fouling is defined as unwanted deposition on the heat exchanger surfaces which retards the heat transfer and declines its performance. In this investigation calcium carbonate (CaCO3) fouling mitigation was achieved by adding clove-treated multiwall carbon nanotubes (C-MWCNT) additive at three variable concentrations (i.e., 0.0143%, 0.0071%, and 0.0036% mass). Water based C-MWCNT nanofluid was selected for its ability to resist the foulant deposition without imposing any corrosion on the heat exchanger surfaces. MWCNT was functionalized with clove extracts for obtaining its suspension in distilled water. After functionalization, thermo-physical properties of all the three different C-MWCNT concentrations of nanofluid and water were investigated with Thermal conductivity meter, density meter, and viscosity meter, which demonstrated the increase in density and thermal conductivity with the increase of C-MWCNT concentration. After that fouling investigation was conducted at a constant heat flux boundary condition where the supersaturated solution of CaCO3 at 300 mg L−1 was used as a fouling liquid. After the fouling experiments, the test coupon was dismantled from the test section for morphological study of the fouling deposits. Field Emission Scanning Electronic Microscopy (FESEM) was used to investigate the morphology of the deposits. The results of CaCO3 mass deposition at variable concentrations of C-MWCNT such as 0%, 0.0143%, 0.00714%, and 0.00357% were 0.1652 g, 0.0993 g, 0.0805 g, and 0.0 584 g respectively, which revealed the inverse relationship between the concentration of water-based C-MWCNT nanofluid and the deposition of CaCO3 foulants on the heat transfer surfaces. [ABSTRACT FROM AUTHOR]

Preserving the ecological health of wetlands has enormous importance in an arid climate. Manchar Lake, located in the arid part of Pakistan, is one of the most vulnerable freshwater lakes and has continuously been exposed to direct pollutants influx. Its vulnerability demands an assessment of pollution loads of trace elements in bed sediments. This study was carried out with sediment samples from 21 locations. Nine trace elements (As, Pb, Fe, Cr, Hg, Cu, Ni, Mn, and Zn) were detected using Inductively Coupled Plasma Mass Spectrometry. Pollution load-related analytical approaches were applied to estimate the contamination loads of individual elements and the aggregated ecological risks. Overall, the mean concentrations of all trace elements in lakebed sediments were detected as: As 5.4, Pb 2.2, Cr 17, Cu 1.5, Fe 165.1, Hg 0.028, Mn 2.6, Ni 7.5, and Zn 64.9 in mg/kg. Results revealed that the lakebed sediment is significantly polluted, primarily with Fe, Zn, Hg, Cr, and As. The spread of these trace elements also varies across locations as many locations do not receive polluted water during dry seasons due to the low water level in the lake. The ecological risk assessment and multivariate analysis findings establish that the Main Nara Valley Drain comprising drainage water from agricultural fields and in part from municipalities is the greatest pollution source to the lake. This dangerous pollution problem calls for action to restore the purity of the natural lake ecosystem. [ABSTRACT FROM AUTHOR]

Purpose: To compare the effectiveness and safety of suprachoroidal versus intravitreal Triamcinolone Acetonide in cases of resistant diabetic macular edema. Study Design: Quasi experimental study. Place and Duration of Study: This research was executed at Retina Department of Al-Ibrahim Eye Hospital, Karachi, Pakistan, from January 2022 to June 2022. Methods: Thirty-four patients with resistant diabetic macular edema were selected through convenient sampling and divided equally into two groups. All patients underwent ocular examination. Group I was given single Intravitreal injection (IVI) of 0.1 mL Triamcinolone Acetonide at 4 mg per 0.1 mL concentration. Group II received same dosage of drug via Suprachoroidal injection (SCI). After 24 hours, they were assessed for side effects. After 6 weeks, second dose of same drug was administered. Patients were followed at 3 and 6 months. Results: No serious side effect was observed in any patient within 24 hours. At 1 month follow-up period, comparison between the two groups for BCVA, CMT and IOP was not significant (p > 0.05). When the two groups were compared at 3 months, both routes were equally effective but IOP remained more stable via SCI route. At 6 months, IOP remained elevated in group I but decreased in group II (p = 0.003). Conclusion: Triamcinolone Acetonide was effective by both routes in resistant diabetic macular edema in terms of improved BCVA and CMT but SCI was better in terms of IOP and cataract progression. [ABSTRACT FROM AUTHOR]

Keenjhar Lake in Pakistan provides several ecosystems services including drinking water to millions of people. The seasonal variation (pre-, during, and post-monsoon) in Keenjhar Lake water quality was investigated during nine sampling rounds at ten locations. Water samples (n = 270) were analyzed for As, Cd, Cr(III), Cu, Fe, Hg, Mn, Ni, and Pb using atomic absorption spectrophotometry, Cr(VI) with a UV spectrophotometer, and water quality parameters (solids, oxygen, conductivity, and pH). Several elements exceeded WHO or Pakistan safe limits for unrestricted use including As (0.038 mg·L−1, 95th upper confidence limit), Cr(III) (0.15 mg·L−1), Cd (0.11 mg·L−1), Fe (0.42 mg·L−1), Ni (0.037 mg·L−1), and Pb (0.04 mg·L−1). Monsoon levels of chromium, Cu, Fe, Mn, and Pb were higher than other seasons, while As was highest during post-monsoon, and Ni was highest during pre and post-monsoon. There were significant spatial differences in metals concentrations in the lake. As, Cu, and Fe significantly declined in concentration with distance from the lake inlet. Using the lake as a source of drinking water presented unacceptable carcinogenic risk and non-carcinogenic hazards. This study suggests measures should be taken to limit discharge of pollution to the lake and future monitoring should consider seasonal monsoon effects on lake quality. [ABSTRACT FROM AUTHOR]

Water pollution related to trace elements has emerged as a worldwide concern owing to their increasing concentration and damages to the aquatic ecosystems. The water ecosystem of Manchar Lake situated in the arid region of Pakistan has also been degraded and posing a severe health risk to the dependent communities. This study aims to investigate the seasonal variability in the influx of trace elements (As, Cd, Cr(III), Cr(VI), Cu, Fe, Hg, Mn, Ni, Pb, and Zn) into the lake during premonsoon, monsoon, and post-monsoon seasons and its consequential health risks. The highest mean concentrations (µg/l) of As (43.2), Cr(III) (101.4), Zn (41), Cu (43.12), Fe (318), Cd (18.5), Mn (27.2), Ni (99.7), Pb (65.91) and Hg (6.8) have been observed in pre-monsoon and Cr(VI) (0.2) in monsoon seasons. The elements exceeding safe limits in pre-monsoon season are As, Cd, Cr(III), Hg, Ni, and Pb, while in monsoon season As, Cd, Ni, and Pb exceed the limit. Evaluation of the degree of contamination depicted high levels of pollution in pre-monsoon and monsoon seasons and the Heavy Metal Evaluation Index indicated a high level of pollution in pre-monsoon, medium in monsoon, and low in the postmonsoon season. The study revealed that oral consumption of lake water potentially causes carcinogenic and non-carcinogenic health risks. However, potential dermal related health risks associated with these metals concentrations in water are within the tolerable ranges. The findings of this study suggest prompt actions to control these pollutants influx into the lake. [ABSTRACT FROM AUTHOR]

Objective: To validate the global registry of acute coronary event (grace) risk score in a Pakistani population at Tabba Heart Institute Karachi in patients with non ST-Elevation Myocardial Infarction (NSTEMI) and Unstable Angina (UA)., Methods: In this prospective Observational registry study, 530 adults hospitalized patients with a diagnosis of Non-ST-Elevation Myocardial Infarction and unstable angina were enrolled between March 2012 and August 2012 at the Tabba Heart Institute, Karachi, Pakistan. For each patient, the grace risk score was calculated and its discrimination evaluated and correlated with in-hospital mortality using the Kendall's tau-b bivariate correlation test. Each patient was grouped either into high, intermediate or low risk groups according to their GRS., Results: A total of 530 patients with NSTEMI and UA were included; the overall mean grace risk score in our population was 131.87 +/- 41.56. The GRACE Risk Score showed good discrimination, with Area under the ROC curve of 0.803 (95% CI 0.705-0.902, P < 0.001). During the in-hospital stay, total of 19 (3.6%) patients died, and out of those 15 (8.4%) patients belonged to high risk group., Conclusion: GRACE RS strongly validates the in-hospital mortality among our patient population presenting with a wide spectrum of complications. However, more multicentre registries on a larger population with long-term follow up are required to study detailed trends in our population.