Fabrication of alginate@silver nanoparticles (Alg@AgNPs) bionanocomposite for the sequestration of crystal violet dye from aqueous solution.

In the present study, alginate@silver nanoparticles (Alg@AgNPs) bionanocomposite has been fabricated successfully and further explored for the removal of crystal violet (CV) dye from the aqueous solution. The surface morphology of the (Alg@AgNPs) bionanocomposite was characterized by various modern analytical techniques such as SEM-EDX, TEM, FTIR and XRD. The maximum adsorption was observed at optimum condition of (pH 7, adsorbent dose 0.01 g, equilibrium time 240 min and initial concentration 20 mg L-1). The maximum monolayer adsorption capacity was found to be 186.93 mg g-1 at 30 °C. The experimental data were further validated by various isotherm models and on the basis of highest correlation coefficient (R2, 0.99), Langmuir model was found to be best fitted model. Pseudo-second order kinetic model obeyed best for the experimental data with a highest correlation coefficient (R2, 0.99) at all studied temperature. In thermodynamic studies, the positive value of enthalpy change (∆H0) and entropy change (∆S0) confirmed the process to be endothermic and spontaneous in nature. Desorption studies shows that 83 % of the adsorbed CV can be desorbed in first cycle and can be regenerated up to 4th cycle effectively with 0.1 M HCl. Therefore, (Alg@AgNPs) bionanocomposite could be harnessed as a potential adsorbent for the removal of hazardous CV dye from the waste water.

A novel, eco-friendly bio-nanocomposite (Alg-Cst/Kal) for the adsorptive removal of crystal violet dye from its aqueous solutions.

Herein, we report the synthesis of a novel bio-nanocomposite (Alg-Cst/Kal) for the effective removal of the dye "Crystal Violet" from its aqueous solutions. In order to observe the surface morphology and functional groups, the bio-nanocomposite was characterized using various techniques such as SEM, EDX, TEM, FTIR, XRD, and TGA. The effect of parameters like contact time, pH, concentration and temperature on the adsorption of the dye over adsorbent has been studied in detail. The dye - adsorbent system has been tested over various isotherm models and found to follow the Freundlich adsorption isotherm model at 303 K. The developed bio-nanocomposite material exhibits an excellent adsorption toward Crystal Violet with a maximum adsorption capacity of 169.49 mg.g-1. The experimental data has been further validated by applying various kinetic models and the pseudo-second order kinetic model was the best suited model. The calculated rate constant values ranged from 0.0046 to 0.0204 g.mg-1.min-1 for different dye concentrations. The positive values of change in enthalpy, ΔH° (9.765 kJ.mol-1) and change in entropy, ΔS° (0.0565 kJ.mol-1.K-1) obtained through thermodynamic studies demonstrate the endothermic nature and spontaneity of the adsorption process, respectively. The adsorption capacity of the adsorbent for the removal of the Crystal Violet dye was also compared with other adsorbents and found maximum. Novelty statement A novel bio-nanocomposite is synthesized by modifying the biopolymer alginate, cysteine and mixing the clay, kaolinite (Kal). The adsorption abilities of the material was tested the on the cationic hazardous dye, Crystal Violet. The material is novel and no attempt has so far been made to examine its batch adsorption abilities to remove hazardous dyes from the wastewater. The results are highly encouraging as out of all the adsorbents tested so far highest adsorption of the dye is observed in the present studies.

Fabrication of a lead ion selective membrane based on a polycarbazole Sn(iv) arsenotungstate nanocomposite and its ion exchange membrane (IEM) kinetic studies.

A polycarbazole-Sn(iv) arsenotungstate (Pcz-SnAT) nanocomposite cation exchanger membrane (CEM) was prepared via the casting solution technique utilizing polycarbazole-Sn(iv) arsenotungstate and PVC (polyvinyl chloride) as a binder. The synthesis of the Pcz-SnAT membrane was confirmed via various characterization methods such as EDX, SEM, TGA, XRD, and FTIR spectroscopy. This membrane having a 4.5 : 1 composition ratio of composite by PVC exhibited the most effective outcomes for swelling, thickness, porosity, and water content. Our research indicates that the present ion selective membrane electrode is selective towards Pb(ii) ions, with the detection limit ranging from 1 × 10-7 mol L-1 to 1 × 10-1 mol L-1 where 20 s is the response time and 3-7 is the working value pH. The mechanism of the Pcz SnAT ion exchange membrane was obtained by kinetic studies by utilizing the equation given by Nernst Planck at 40-80 °C. As a result, activation energy and thermodynamic studies were done. The analytical utility of this electrode is conventional by utilizing it as an electrode indicator within the potentiometric titration.

Sequestration of toxic congo red dye from aqueous solution using ecofriendly guar gum/ activated carbon nanocomposite.

In the present study, a potential Guar gum/activated carbon nanocomposite as an adsorbent was synthesized and utilized for the sequestration of toxic congo red dye from synthetic wastewater. The nanocomposite was characterized using different techniques such as SEM, EDX, TEM, FTIR and XRD. Various physico-chemical parameters such as influence of contact time, pH, adsorbent dose, temperature and initial dye concentration were investigated to optimize conditions for maximum adsorption of congo red. Equilibrium data fitted well with Langmuir isotherm model having maximum adsorption capacity of 831.82 mgg-1 at 313 K. The kinetic studies demonstrated that the adsorption followed a pseudo-second order kinetic model. The thermodynamic study showed that the adsorption of congo red onto nanocomposite was spontaneous, exothermic with decreased in randomness at solid/liquid interface. The regeneration study indicated that the nanocomposite could be reused successfully upto five consecutive cycles. Therefore, the present material can be effectively and efficiently urilized for the removal of congo red dye from aqueous solution as well as industrial wastewater.

Detection, quantification and genotype distribution of HCV patients in Lahore, Pakistan by real-time PCR.

BACKGROUND: Hepatitis C virus (HCV) is considered as "Viral Time Bomb" suggested by the World Health Organization and if it is not treated timely, it will lead towards cirrhosis and hepatocellular carcinoma (HCC). OBJECTIVE: The purpose of the present research is to study possible risk factors, frequent genotypes of HCV and its association with different age groups. METHODS: Suspected blood samples from HCV patients were collected from different hospitals of Lahore, Pakistan. Out of 1000 HCV suspected samples, 920 samples were found HCV positive detected by Anti-HCV ELISA, CobasR. kit. The quantification of HCV load was determined by HCV quantification kit and LINEAR ARRAY KIT (Roche) was used for genotype determination by Real-Time PCR (ABI). Statistical analysis was done by using Microsoft Excel. RESULTS: Out of 920 subjects, 77 subjects (8.4%) were false positive and they were not detected by nested PCR. Three PCR positive samples were untypeable. Genotype 3 was predominant in Lahore which was 83.5%, whereas type 1 and 2 were 5.1% and 0.7% respectively. There were also mixed genotypes detected, 1 and 3 were 0.4%, 2 and 3 were 1.41% and 3 and 4 were 0.2% only. Male were more infected of HCV in the age <40 years and females >40years. CONCLUSION: The major risk factor for HCV transmission is by use of unsterilized razors/blades. It is necessary to spread awareness among the general population of Pakistan about HCV transmission risk factors. Regular physical examination at least once a year is recommended, so that early detection of HCV could be done.

Auxiliary principle technique and iterative algorithm for a perturbed system of generalized multi-valued mixed quasi-equilibrium-like problems.

In this article, we introduce a perturbed system of generalized mixed quasi-equilibrium-like problems involving multi-valued mappings in Hilbert spaces. To calculate the approximate solutions of the perturbed system of generalized multi-valued mixed quasi-equilibrium-like problems, firstly we develop a perturbed system of auxiliary generalized multi-valued mixed quasi-equilibrium-like problems, and then by using the celebrated Fan-KKM technique, we establish the existence and uniqueness of solutions of the perturbed system of auxiliary generalized multi-valued mixed quasi-equilibrium-like problems. By deploying an auxiliary principle technique and an existence result, we formulate an iterative algorithm for solving the perturbed system of generalized multi-valued mixed quasi-equilibrium-like problems. Lastly, we study the strong convergence analysis of the proposed iterative sequences under monotonicity and some mild conditions. These results are new and generalize some known results in this field.

An iterative algorithm for a system of generalized implicit variational inclusions.

In this paper, we introduce a system of generalized implicit variational inclusions which consists of three variational inclusions. We design an iterative algorithm with error terms based on relaxed resolvent operator due to Ahmad et al. (Stat Optim Inf Comput 4:183-193, 2016) for approximating the solution of our system. The convergence of the iterative sequences generated by the iterative algorithm is also discussed. An example is given which satisfy all the conditions of our main result.

Combination of needle aspiration and core needle biopsy: A new technique of stereotactic biopsy.

AIM: The study aims at describing the results of using a new technique to acquire the tissue sample in stereotactic biopsy of brain lesions. MATERIALS AND METHODS: The study was performed in 19 patients over a period of 5 years in which we used the new technique, i.e., Abrar and Afzal technique (AT) of obtaining tissue biopsy. It is a combination of core tissue biopsy and needle aspiration techniques. The technique was devised to acquire greater amount of tissue for pathologic study. RESULTS: While we could give pathologic diagnosis in 18 patients out of 19 (94.7%), in one patient, the tissue sample revealed only inflammatory cells and definitive diagnosis could not be reached. There was no significant morbidity or any mortality in the series. CONCLUSION: Abrar and Afzal technique is a reasonably accurate technique of acquiring larger tissue sample in stereotactic brain biopsy without any additional risks. It can be done with little modification of the conventional equipment available with the stereotactic system.

Generalized equilibrium problem with mixed relaxed monotonicity.

We extend the concept of relaxed α-monotonicity to mixed relaxed α-ß-monotonicity. The concept of mixed relaxed α-ß-monotonicity is more general than many existing concepts of monotonicities. Finally, we apply this concept and well known KKM-theory to obtain the solution of generalized equilibrium problem.

Adsorptive removal of Pb2+ form aqueous solution by macrocyclic calix[4]naphthalene: kinetic, thermodynamic, and isotherm analysis.

BACKGROUND: The adsorption characteristics of Pb(2+) ions from aqueous solutions onto calix[4]naphthalene have been investigated. METHOD: Calix[4]naphthalene was prepared by the condensation of 1-naphthol and formaldehyde (1:2) in presence of hydrochloric acid at 80 °C. The effect of various operation parameters, such as solution pH, initial metal ion concentration, contact time, and temperature, on the adsorption capacity of calix[4]naphthalene for Pb(2+) have been investigated. RESULT: Experimental results showed that the adsorption of Pb(2+) ions increased with the increase in solution pH and temperature. Langmuir and Freundlich isotherms models were used to describe the adsorption behavior of Pb(2+) by calix[4]naphthalene. Equilibrium data fitted well with the Langmuir isotherm model and the maximum adsorption capacity of calix[4]naphthalene for Pb(2+) at 30 °C was found to be 29.15 mg g(-1). Kinetic studies indicated that the adsorption followed pseudo-second order model and the thermodynamic studies revealed that the adsorption process was spontaneous and endothermic in nature. The obtained results demonstrated that calix[4]naphthalene can be used as an effective adsorbent for Pb(2+) ions removal from water.

Crowding, molecular volume and plasticity: an assessment involving crystallography, NMR and simulations.

The discrepancy between the X-ray and NMR structures of Mycobacterium tuberculosis peptidyl-tRNA hydrolase in relation to the functionally important plasticity of the molecule led to molecular dynamics simulations. The X-ray and the NMR studies along with the simulations indicated an inverse correlation between crowding and molecular volume. A detailed comparison of proteins for which X-ray and the NMR structures appears to confirm this correlation. In consonance with the reported results of the investigations in cellular compartments and aqueous solution, the comparison indicates that the crowding results in compaction of the molecule as well as change in its shape, which could specifically involve regions of the molecule important in function. Crowding could thus influence the action of proteins through modulation of the functionally important plasticity of the molecule.

Structures of new crystal forms of Mycobacterium tuberculosis peptidyl-tRNA hydrolase and functionally important plasticity of the molecule.

The X-ray structures of new crystal forms of peptidyl-tRNA hydrolase from M. tuberculosis reported here and the results of previous X-ray studies of the enzyme from different sources provide a picture of the functionally relevant plasticity of the protein molecule. The new X-ray results confirm the connection deduced previously between the closure of the lid at the peptide-binding site and the opening of the gate that separates the peptide-binding and tRNA-binding sites. The plasticity of the molecule indicated by X-ray structures is in general agreement with that deduced from the available solution NMR results. The correlation between the lid and the gate movements is not, however, observed in the NMR structure.

Impact of temperature and precipitation on propagation of intestinal schistosomiasis in an irrigated region in Ethiopia: suitability of satellite datasets.

OBJECTIVE: To assess the suitability of satellite temperature and precipitation datasets for investigating the dependence of Schistosoma mansoni disease transmission on meteorological conditions in an irrigated agricultural region in Ethiopia. METHODS: Data used were monthly number of patients infected with S. mansoni and seeking treatment at the local hospital, monthly maximum air temperature from a local weather station, monthly average land surface temperature from MODIS satellite data, monthly total precipitation from a local rain gauge and precipitation estimates from four widely used satellite products, namely, TMPA 3B42RT, TMPA 3B42, CMORPH and PERSIANN. The number of patients was used as proxy for vector abundance. RESULTS: Temperature and precipitation play a role in the transmission of S. mansoni disease. There is a weak but significant positive correlation between monthly maximum air temperature derived from a meteorological station (or average land surface temperature derived from MODIS satellite product) and the number of patients in the same month. There is a significant negative correlation between monthly precipitation volume (derived from rain gauge or satellite data) and number of patients at lags of 1 and 2 months. CONCLUSION: Satellite temperature and precipitation products provide useful information to understand and infer the relationship between meteorological conditions and S. mansoni prevalence.

Anaerobic biodegradation of triphenylmethane dyes in a hybrid UASFB reactor for wastewater remediation.

Anaerobic digestions have been proved more successful than aerobic systems for the degradation and destruction of dye-containing wastewaters. The performance of a hybrid up flow anaerobic sludge-filter bed (UASFB) reactor was tested with a synthetic wastewater containing Crystal violet (CV) as a carbon source and sodium acetate as a co-substrate. Continuous feeding of the reactor started with an initial OLR of 0.9 g COD/l-d and then it was increased step wise to 4 g COD l(-1) d(-1), while maintaining constant HRT (24 h). The optimum pH value and temperature for decolorization of crystal violet by this mixed culture species under anaerobic conditions were found to be 8-9 and 30-35°C respectively. N,N-dimethylaminophenol and N,N-bis (dimethylamino) benzophenone (Michler's Ketone) were detected as the degradative metabolites of Crystal Violet. Subsequently, N,N-dimethylaminophenol was further degraded to aniline in the reactor whereas Michler's ketone was not degraded under anaerobic conditions. The UASFB bioreactor was able to remove the CV completely up to a loading rate of 100 mg CV l(-1)d(-1).

Hybrid UASFB-aerobic bioreactor for biodegradation of acid yellow-36 in wastewater.

In this study, a combined anaerobic-aerobic treatment process based on mixed culture of bacteria was used to degrade azo dyes (AY-36). The experiment was integrated by exposing anaerobic granular sludge and aerobic aromatic amine degrading bacterial enrichment cultures. Under anaerobic conditions UASFB bioreactor using sodium acetate as a co-substrate, the AY-36 was reduced and resulting in a temporary accumulation of aromatic amines by the bacterial biomass. Hydraulic residence time (HRT) was fixed (24 h) through out the experiment. The two aromatic amine p-amino diphenylamine (p-ADPA) and 4-aminobenzenesulfonic acid (4-ABS) were detected from the reduction of AY-36. Subsequently, 4-ABS was degraded in the aerobic reactor which was earlier accumulated for 30days. But p-ADPA was not degraded in aerobic condition. The combined anaerobic-aerobic bioreactor was able to completely remove the AY-36 at a maximum loading rate of 100mg AY-36L(-1)d(-1).

Adsorption studies of hazardous malachite green onto treated ginger waste.

Adsorption of malachite green (MG) from aqueous solution onto treated ginger waste (TGW) was investigated by batch and column methods. The effect of various factors such as initial dye concentration, contact time, pH and temperature were studied. The maximum adsorption of MG was observed at pH 9. Langmuir and Freundlich isotherms were employed to describe the MG adsorption equilibrium. The monolayer adsorption capacities were found to be 84.03, 163.9 and 188.6 mg/g at 30, 40 and 50 degrees C, respectively. The values of thermodynamic parameters like DeltaG degrees , DeltaH degrees and DeltaS degrees indicated that adsorption was spontaneous and endothermic in nature. The pseudo second order kinetic model fitted well in correlation to the experimental results. Rechienberg's equation was employed to determine the mechanism of adsorption. The results indicated that film diffusion was a major mode of adsorption. The breakthrough capacities were also investigated.

Histological pattern of primary malignant lung tumours diagnosed in a tertiary care hospital: 10 year study.

Lung cancer is the most frequently diagnosed cancer in the world and is the second commonest cancer according to hospital-based data from Kashmir, India. The objective of this study was to assess the histopathological pattern of primary malignant tumours of lung at a tertiary care hospital among smokers and non-smokers of both sexes. A total of 783 cases over a 10 years period, were studied, including 685 males and 98 females with a mean age at presentation of 57.8 years. The most common histological type of tumour in both sexes was squamous cell carcinoma (71.3 per cent), followed by small cell carcinoma (20.8 per cent), adenocarcinoma (2.6 per cent), bronchioalveolar carcinoma (1.8 per cent) while other tumours constituted 3.6 per cent. The two main histological subtypes of lung cancer found among smokers was squamous cell carcinoma (72.2 per cent) and small cell carcinoma 22.9 per cent. The smoker to non-smoker ratio was 2.14:1.

Studies on adsorption of crystal violet dye from aqueous solution onto coniferous pinus bark powder (CPBP).

The present study shows that the coniferous pinus bark powder (CPBP) can be used as a potential adsorbent for the removal of crystal violet (basic dye) from aqueous solutions. Experiments were carried out as a function of contact time, concentration, temperature, pH and dosage. The amount of dye uptake was found to vary with increasing initial solution pH and maximum adsorption was observed at pH 8. The equilibrium was attained in 2h. The amount of dye uptake (mg/g) was found to increase with increase in dye concentration and contact time. The % adsorption was found to decrease with increase in amount of adsorbent. The thermodynamic parameters were also calculated and the positive value of DeltaH degrees indicates the endothermic nature of adsorption. The applicability of the three isotherm's model for the present data follows the order: Langmuir>Temkin>Freundlich. The kinetics of crystal violet on to the adsorbent can be described well by pseudo-second order>Elovich>pseudo-first order equation.

Recycling of ribosomal complexes stalled at the step of elongation in Escherichia coli.

Translating ribosomes often stall during elongation. The stalled ribosomes are known to be recycled by tmRNA (SsrA)-mediated trans-translation. Another process that recycles the stalled ribosomes is characterized by peptidyl-tRNA release. However, the mechanism of peptidyl-tRNA release from the stalled ribosomes is not well understood. We used a defined system of an AGA-minigene containing a small open reading frame (ATG AGA AGA). Translation of the AGA-minigene mRNA is toxic to Escherichia coli because it stalls ribosomes during elongation and sequesters tRNA(Arg4) as a short-chain peptidyl-tRNA(Arg4) in the ribosomal P-site. We show that a ribosome recycling factor (RRF)-mediated process rescues the host from the AGA-minigene toxicity by releasing the peptidyl-tRNA(Arg4) from the ribosomes. The growth phenotypes of E. coli strains harboring mutant alleles of RRF and initiation factor 3 (IF3) genes and their consequences on lambdaimmP22 phage replication upon AGA-minigene expression reveal that IF3 facilitates the RRF-mediated processing of the stalled ribosomes. Additionally, we have designed a uracil DNA glycosylase gene construct, ung-stopless, whose expression is toxic to E. coli. We show that the RRF-mediated process also alleviates the ung-stopless construct-mediated toxicity to the host by releasing the ung mRNA from the ribosomes harboring long-chain peptidyl-tRNAs.

Adsorption studies on teak leaves (Tectona grandis): removal of lead ions from wastewater.

Teak leaves (Tectona grandis) abundantly available in India showed high sorption capacity for lead ions and were found efficient for the removal of lead ions from aqueous solutions. The extent of removal was found to be dependent on pH, temperature, concentration of metal ions and the dose of adsorbent. Thermodynamic parameters were calculated at different temperatures. The sorbent once used can be regenerated and recycled two - three times almost with the same capacity. However, regeneration by column operation gave better results than batch process.