ZnSe-rGO nanocomposites as photocatalysts for purification of textile dye contaminated water: A green approach to use wastewater for maize cultivation

Disputes about the probable availability of safe water and the efficacy of processed wastewater are key issues that necessitate a suitable solution to enhance the quality of clean water. The current research emphasizes the synthesis of ZnSe-reduced graphene oxide nanocomposites (ZnSe:rGO) with different weight ratios of rGO (represented as X = 0.6, 1 and 1.6 g)via one-step hydrothermal method. The photocatalytic performance for the degradation of methyl violet (MV) dye was investigated under visible light irradiation by varying the reaction parameters. The crystal structure, elemental composition, surface functionality and morphology of the synthesized ZnSe-XrGO nanocomposites were estimated by powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopic (SEM) techniques. UV-visible spectroscopy was used to investigate the optical properties. The highest efficiency is obtained for ZnSe-XrGO in 1:1 and it showed pseudo 1st order behavior with rate constant of 0.0167min-1and 94 % photodegradation of MV in just 3 h. Furthermore, hazardous effects of MV were investigated on the germination and growth of Zea mays seeds by giving them aqueous solution of MV (0, 8, 12, 24 and 48 ppm) and the decontaminated water after photodegradation of MV with the synthesized photoactive composite. The results showed profound negative effect on both germination and seedling growth at higher concentration (>12 ppm) of the dye solution. No hazardous effects were observed on both these parameters when it was given the dye degraded water which reflects the practical use of the synthesized catalyst for water remediation. The current study fulfills the goal of designing an efficient visible-light active nano-photocatalyst and its direct applicability on life sciences for water purification.

Temperature-dependent conduction mechanism of NiO@Carbon@Polypyrrole nanomaterial with EMI shielding characteristics

A simple hydrothermal technique and in-situ chemical oxidative polymerization of pyrrole monomer yield the functionalized NiO@C@PPy nanomaterial for electromagnetic shielding applications. The crystal structure, morphology, dielectric and electromagnetic shielding (EMI) performance in the X-band (8.2-12.4 GHz) is thoroughly studied. Impedance spectroscopy is utilized to study the electrical response of a NiO@C@PPy pellet. This study focuses on the modulations of relaxation time with frequency at different temperatures. In the NiO@C@PPy composite, a semiconductor-to-metal transition (SMT) is observed, at 328 K. The conduction mechanism of NiO@C@PPy is explained based on the carrier hopping transport model in Ni2+ and Ni3+ ions. It is evident from the activation energy value (Ea ≈ 0.32 eV) determined from impedance, conductivity, and dielectric data that the relaxation and conduction processes correspond to the same electro-active region. Using the variable range hopping (VRH) model localization length of the carrier is calculated to be 1.56 Å. The NiO@C@PPy sample demonstrated enhanced conductivity and low dielectric values which are vital in EMI shielding applications. Consequently, the electromagnetic interference shielding effectiveness is found to be 21.9 dB of NiO@C@PPy in the X-band frequency range. This composite material is a good candidate for high frequency shielding applications.

ZnO@C Microballs Wrapped with Ni(OH)2 Nanofilms for Electrochemical Sensing of Glucose and Hydrogen Peroxide

Tailor-made metal oxide/hydroxide core-shell structures are promising for the fabrication of an effective electrocatalyst. Here, we report the development of a core-shell structure based on carbon-doped and Ni(OH)2 nanofilms wrapped ZnO microballs (NFs-Ni(OH)2/ZnO@C MBs) for glucose and hydrogen peroxide (H2O2) monitoring. The unique ball-like morphology of the designed structure is achieved through a facile solvothermal strategy by the control of reaction conditions. Typically, ZnO@C MBs offer highly conductive core, and the shell of Ni(OH)2 nanofilms increases the density of catalytic active sites. The interesting morphology and the brilliant electrocatalytic efficacy of designed hybrid, encourage us to design a multi-mode sensor for glucose and H2O2 screening. The NFs-Ni(OH)2/ZnO@C MBs/GCE glucose sensor presented good sensitivities (647.899 & 161.550 μA (mmol L-1)-1 cm-2), a quick response (＜4 s), lower limit of detection (0.04 μmol L-1), and wide detection range (0.004-1.13 & 1.13-5.02 mmol L-1). Similarly, the same electrode revealed excellent H2O2 sensing features including good sensitivities, two linear parts of 3.5-452 and 452-1374 µmol L-1, and detection limit of 0.03 μmol L-1 as well as high selectivity. Thus, the development of novel hybrid core-shell structure is useful for potential applications in glucose and H2O2 screening from environmental and physiological samples.

Population diversity of sheep bot fly, Oestrus ovis (Linné, 1758) (Diptera: Oestridae: Oestrinae), using SDS polyacrylamide gel electrophoresis

The study was planned to evaluate the inter, and intra population genetic variation in general protein banding pattern in Oestrus ovis larvae, by using 10% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE). The larvae were collected from slaughtered goats head from five different locations (AAS, PN, LA, GM, and BC) of Karachi, Pakistan. The data obtained was subjected to POPGENE (Population Genetic Analysis) software for analysis. The polymorphic loci within populations ranged from 45.45% to 90.91%. Polymorphic loci observed in all populations were 90.91%. The expected heterozygosity observed was 0.182 ± 0.096 in all populations. The chi-square test showed 5 out of 11 loci at H-W equilibrium. The overall fixation index (FST) value was 0.108, showing that the likelihood of subpopulations being differentiated from one another is about 11 percent. The gene flow value (Nm = 2.065) was higher, showing that genes flow occurs between populations. The values of genetic identity were greater, and genetic distance were smaller among all the populations, which means that all the populations were more alike and closer to each other. It was concluded that there was no sympatric and parapatric population differentiation observed among all the population of O. ovis and the populations of the five different locations were not genetically and reproductively isolated from each other.

Occurrence of cestodes and comparative efficacy of Typha angustata and sulphadimidine against cestodes in Columba livia domestica (Domestic Pigeon)

The occurrence of intestinal parasites of Columba livia domestica has been on the increase, leading to high economic and production losses with more fatal cases. This study was designed to investigate the prevalence of cestodes in pigeons and determine the efficacy of Typha angustata extract and sulphadimidine against these cestodes in the domestic pigeon. A total of 30 pigeons were examined. 18 (60%) pigeons were found infected with only one type of cestode species (Raillietina spp.). The difference in prevalence between males and females was statistically significant (χ² = 8.167, p = 0.004). The mean EPG count in group A (treated with T. angustata extract) before treatment and after treatment was 176 ± 4.33 and 155 ± 4.24, respectively. In group B (treated with sulphadimidine), the mean EPG calculated before treatment and after treatment was 184 ± 6.74 and 35 ± 3.53, respectively. The efficacy at day 28 of T. angustata and Sulphadimidine was 11.93% and 80.97%, respectively. It was concluded on the basis of the EPG and efficacy data that T. angustata extract had low efficacy against raillietiniasis, while as sulphadimidine, which is also used before to treat different intestinal parasites, had a good efficacy against raillietiniasis. Further studies are required to know the prevalence of other gastrointestinal parasites in pigeons and efficacy of different medicinal plants against such parasites.

Identification of terrestrial gastropods families found in district Swat, Pakistan

Very little is known about the malacofauna in district Swat of Khyber Pakhtunkhwa province, situated in the Northern part of Pakistan. The Swat valley possesses a variety of suitable environmental conditions, providing different types of habitats for both flora and fauna. Taken into consideration these points, the present study was conducted to explore the terrestrial snails diversity in agricultural and non-agricultural fields in the lower Swat valley. A total of 417 shells were collected from three sites: Kokarai, Kanju Township, and Deolai. Based on conchological features, three families: Bradybaenidae, Hygromiidae, and Zonitidae were identified using different terrestrial snail keys. In Kokarai and Deolai, shells of members of all the above-mentioned families were found from agricultural fields. In Kanju Township, shells of members of the family Bradybaenidae and Zonitidae were found. From these findings, it was concluded that district Swat possesses a significant malacofauna which was unexplored before and aided more to the existing literature on malacofauna. It also supports the idea that the agroecosystem is rich in species diversity. Further in-depth and extensive study is recommended to be carried out for a detailed taxonomy of the described terrestrial gastropod families.

Facile synthesis of hydrogel-nickel nanoparticle composites and their applications in adsorption and catalysis

Homopolymer bulk hydrogel of methacrylic acid was synthesized through a new single-step facile rout and used as a template for the fabrication of nickel (Ni) nanoparticles and as adsorbent to remove methylene blue (MB) and Rhodamine-6G (Rh-6G) from water. The Ni nanoparticles containing composite hydrogel was applied as catalyst for the degradation of a nitro compound. The carboxylic groups acted as highly efficient adsorption sites and their high degree was responsible for the removal of huge amounts of MB and Rh-6G from water. The maximum adsorption capacity of poly (methacrylic acid) hydrogel was 685 mg g−1 for MB and 1571 mg g−1 for Rh-6G. The adsorption data of MB was best fitted with Langmuir adsorption isotherm while that of Rh-6G with Temkin adsorption isotherm. Catalytic property of prepared hydrogel integrated with Ni nanoparticles was evaluated by using it as a catalyst for the degradation of 4-nitrophenol (4-NP). The apparent rate constant (k app) observed in this study for the reduction of 4-NP was as high as 0.038 min−1. It was found that this catalyst system can be used repetitively with a slight decrease in catalytic activity.

Impact of city effluents on water quality of Indus River: assessment of temporal and spatial variations in the southern region of Khyber Pakhtunkhwa, Pakistan

The impact of city effluents on water quality of Indus River was assessed in the southern region of Khyber Pakhtunkhwa, Pakistan. Water samples were collected in dry (DS) and wet (WS) seasons from seven sampling zones along Indus River and the physical, bacteriological, and chemical parameters determining water quality were quantified. There were marked temporal and spatial variations in the water quality of Indus River. The magnitude of pollution was high in WS compared with DS. The quality of water varied across the sampling zones, and it greatly depended upon the nature of effluents entering the river. Water samples exceeded the WHO permissible limits for pH, EC, TDS, TS, TSS, TH, DO, BOD, COD, total coliforms, Escherichia coli, Ca²⁺, Mg²⁺, NO₃^-, and PO₄^2-. Piper analysis indicated that water across the seven sampling zones along Indus River was alkaline in nature. Correlation analyses indicated that EC, TDS, TS, TH, DO, BOD, and COD may be considered as key physical parameters, while Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl^-, F^-, NO₃^-, PO₄^2-, and SO₄^2- as key chemical parameters determining water quality, because they were strongly correlated (r > 0.70) with most of the parameters studied. Cluster analysis indicated that discharge point at Shami Road is the major source of pollution impairing water quality of Indus River. Wastewater treatment plants must be installed at all discharge points along Indus River for protecting the quality of water of this rich freshwater resource in Pakistan.

Assessing impact of effluent discharge on irrigation water quality in southern region of Khyber Pakhtunkhwa, Pakistan

Chemical quality and extent of pollution in effluent-contaminated irrigation water collected from two sectors (X and Y) of peri-urban southern regions of Khyber Pakhtunkhwa, Pakistan, were investigated. Various physico-chemical parameters like pH, EC, TS, TSS, TDS, TH, cations (Na¹⁺, K¹⁺, Li¹⁺, Ca²⁺, Mg²⁺), anions (Cl^1-, F^1-, HCO₃^1-, NO₃^1-, SO₄^2-), and heavy metals (Cr, Fe, Cu, Zn, Pb, Cd) were determined. The data indicated wide ranges of variation in all the parameters. Concentration of physico-chemical properties such as EC, TS, TSS, TH, Li¹⁺, Ca²⁺, Mg²⁺, and HCO₃^1- and heavy metals (Cr, Fe, Cu, and Cd) exceeded WHO permissible limits. The distribution of heavy metals in two sampling areas followed the increasing order as Fe > Cr > Cd > Cu > Pb > Zn. The Piper diagram showed that water in the region was of alkaline type. Strong positive correlations were observed among most of the parameters; however, pH was negatively correlated with most of the parameters. According to principle component analysis, parameters causing variations in water quality were mainly EC, TDS, TS, TSS, TH, Na¹⁺, K¹⁺, Ca²⁺, Mg²⁺, F^1-, NO₃^1-, SO₄^2-, Cr, Fe, Cu, and Zn. Linear regression analysis revealed that heavy metals like Cr, Fe, and Cu concentrations were strongly correlated having an R ² value of 0.92 at P ≤ 0.001 with pH. Overall, the results suggested that irrigation water of the area was not fit for irrigation purposes and might cause serious threats for safe, healthy food and feed production. Proper monitoring of water of the said area should be carried out, and quality of irrigation water should be checked from time to time.

Hypophosphatemic effect of niacin extended release in ischemic kidney disease

Ischemic nephropathy is an emerging cause of end stage renal disease, associated with many co-morbidities especially cardiovascular disease risk and derangement in calcium-phosphorus homeostasis resulting in hyperphosphatemia, influencing bones, a characteristic of advancing chronic kidney disease. The management of elevated serum phosphorus has been a challenge in this patient population with compromised kidney performance, as available phosphorus lowering agents possess many undesirable hazardous secondary effects and/or are very expensive. While niacin in different formulation is known to not only correct dyslipidemia but also reduce phosphorus level, but its clinical use restricted owing to side effects. The objective of present study is to evaluate such effect of niacin extended release (NER) in ischemic nephropathy. The chronic kidney disease patients fulfilling the pre-defined criteria were randomly categorized into two groups of equal size (n=60) and prescribed either atorvastatin 20 mg/day or NER 500 mg/day with the same dose of statin for four months. A control of 50 healthy characters matched was also incorporated for local reference range. Baseline and follow up phosphorus concentration was measured and means were compared using t-test at SPSS version 17 with 0.05 chosen alpha. There was no difference in the baseline levels in both groups while significant (p<0.001) hyperphosphatemia was observed in both units as compared with healthy controls. The administration of atorvastatin alone for four weeks showed an insignificant decrease in phosphorus, whereas, NER significantly reduced phosphorus (p<0.001). The mean percent change from baseline to follow up further endorsed the finding as statin alone brought -13.8 % reduction in phosphorus and NER -47 % from baseline. NER, at its lowest prescribed dose once a day was well tolerated by most of the patients and demonstrated significant goal achievement of phosphorus reduction. It is concluded that NER even at low doses in renal compromised dyslipidemic patients may be a promising approach to prevent the harmful vascular, valvular effects caused by hyperphosphatemia in addition to its principal target of HDL-C elevation.

Association of high-density lipoprotein cholesterol with improvement of endothelial dysfunction recovery in renovascular disease

INTRODUCTION

This study was aimed to assess the ratio of total cholesterol (TC) to high-density density lipoprotein cholesterol (HDLC) and plasma nitrate levels in patients with ischemic nephropathy receiving statins and niacin extended release (NER).

MATERIALS AND METHODS

Kidney disease patients with a history of at least 5 year of diabetes mellitus or 10 year of hypertension were screened by renal artery Doppler ultrasonography. Participants were randomly assigned into two groups to receive atorvastatin, 20 mg/d, with and without NER, 500 mg/d, for 16 weeks. Serum levels of lipid profile, creatinine, and nitrate were compared before and after the study.

RESULTS

Fifty-four patients received the statin and 51 received statin-NER combination. Both statin and statin-NER groups demonstrated significant decreases in plasma levels of TC and low-density lipoprotein cholesterol. Triglyceride and very low-density lipoprotein cholesterol were significantly lowered only with statin-NER combination. The increase in HDLC level was found in both groups, but significant only with statin-NER combination therapy (P < .001). Atorvastatin combined with NER reduced TC/HDLC ratio almost double as compared with that of atorvastatin alone (102% and 36.6% reduction, respectively). A similar pattern was observed for nitrate levels (33% and 65%, respectively).

CONCLUSIONS

These findings indicated that a reduction in TC/HDLC ratio improves endothelial function in renovascular disease and use of NER in combination with atorvastatin may provide better outcomes. This could be helpful in attenuating further vascular damage and associated systemic complications.

Obesity: an independent risk factor for systemic oxidative stress

The role of obesity in diabetes mellitus, hyperlipidemia, colon cancer, sudden death and other cardiovascular diseases has confirmed in many recent research studies. In present study, it is hypothesized that obesity can serve as an independent risk factor for the decreased activities of cytoprotective antioxidants in humans and for the associated systemic oxidative stress. 150 age matched, female subjects with no history of smoking or biochemical evidence of diabetes mellitus, hypertension, hyperlipidemia, renal or liver disease or cancer were included in the study and were divided into different grades of obesity according to their body mass index (BMI). Hemoglobin and erythrocyte glutathione (GSH) concentrations were measured for each subject. The study suggests that increase BMI was found to be associated with a significant decrease in erythrocyte glutathione concentration. From these observations it is concluded that obesity even in the absence of smoking, diabetes mellitus, hyperlipidemia, renal or liver diseases can decrease the activities of body's protective antioxidants, and can enhance the systemic oxidative stress and should therefore receive the same attention as obesity with complications.

Frequency of intestinal parasitic infestation in children of 5-12 years of age in Abbottabad

BACKGROUND

Worm infestation is a major problem in children from developing countries due to bad hygienic conditions. It produces nutritional deficiencies and anaemia in children, especially when hookworm infestation is present.

METHODS

This cross-sectional study deals with investigation of the frequency of intestinal parasitic infestation in children between the ages 5-12 years. A total of 283 subjects were tested and screened for different intestinal parasites at of Department of Physiology, Ayub Medical College, Abbottabad. Negative cases were re-examined and if found free of intestinal pathogenic parasites were labelled as negative.

RESULTS

Of the 283 children examined, 230 tested positive for various intestinal parasites. The frequency of helminthic infestation was found to be above 81%. There were 8 different species of helminths and protozoa found in the specimens. By far the highest frequency of 48% was noted for Ascaris lumbricoides while 6.9% (16 cases) of the specimens examined had mixed infestation. The mean Haemoglobin (Hb) level was found to be 9.82 g/dl in males and 9.0 g/dl in females. Virtually no Hookworm infestation was found which may be the reason of not so low Hb level of the subjects.

CONCLUSIONS

A very high percentage (81%) of children from suburbs of Abbottabad have intestinal worm infestation and majority of them (48% of positive cases) have Ascaris lumbricoides. Children were not very severely anaemic because of virtually no hook worm cases.