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1.
Antibiotics (Basel) ; 13(2)2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38391519

RESUMEN

The indiscriminate use of antibiotics in agriculture has raised concerns about antibiotic residues in food products, necessitating robust analytical methods for detection and quantification. In this study, our primary aim was to develop a robust and advanced liquid chromatography-tandem mass spectrometry (LC-MS/MS) methodology specifically designed for the accurate quantification of ticarcillin degradation products in tomato leaves. The choice of ticarcillin as the target analyte stems from its frequent use in agriculture and the potential formation of degradation products, which can pose a threat to food safety. The use of tomatoes as the target sample matrix in this study is justified by their significance in human diets, their widespread cultivation, and their suitability as a model for assessing antibiotic residue dynamics in diverse agricultural environments. By optimizing the MS/MS parameters, the study successfully demonstrates the practicality and reliability of the employed LC-MS/MS method in accurately assessing ticarcillin degradation product (Thiophene-2-Acetic acid and Thiophene-3-Acetic acid) levels. The chromatographic separation was achieved using a specialized column, ensuring high resolution and sensitivity in detecting analytes. Multiple reaction monitoring (MRM) data acquisition was employed to enhance the selectivity and accuracy of the analysis. The developed method exhibited excellent linearity and precision, meeting the stringent requirements for antibiotic residue analysis in complex matrices. Key outcomes of this study include the successful identification and quantification of ticarcillin and its degradation products in tomato leaves, providing crucial insights into the fate of this antibiotic in agricultural settings. The methodology's applicability was further demonstrated by analyzing real-world samples, highlighting its potential for routine monitoring and ensuring food safety compliance. In summary, our study constitutes a noteworthy advancement in the domain of antibiotic residue analysis, offering a reliable method for quantifying ticarcillin degradation products in tomato leaves. The optimized parameters and MRM-based LC-MS/MS approach enhance the precision and sensitivity of the analysis, opening up opportunities for further studies in the assessment of antibiotic residues in agricultural ecosystems.

2.
Artículo en Inglés | MEDLINE | ID: mdl-37957499

RESUMEN

This study focuses on determining the optimum external operating parameters of algal cell lysis for extraction of bio-oil from Chlorella biomass. Response surface methodology has been applied to a regression analysis model for optimizing solvent ratios, i.e., ethyl acetate to ethanol (E.A.:E) ratio for maximum extraction of bio-oil and aqueous deep eutectic solvent to biomass (aDES:biomass) ratio for algal pretreatment for the enhanced yield of bio-oil. Optimized process conditions were 15 min of homogenization combined with ultrasonication (hybrid method). The aDES:biomass ratio of 8.25 caused the highest cell disruption efficiency to liberate bio-oil from encapsulated cells. The solvent ethyl acetate to ethanol ratio (E.A.:E) was optimum at 0.8 for maximum extraction of bio-oil, and studies indicated a maximum bio-oil yield of 94.0% using this hybrid pretreatment process combined with ultrasonication and homogenization. The GC-MS characterization technique was used to analyze the bio-oil, which showed it consisted of 67.93% Di-ethyl phthalate (DEP) and 32.07% esters compounds (C12-C40 hydrocarbons range). The produced DEP from Chlorella biomass using this sustainable green approach is very promising. The estimated cost was around Rs 49 per gm (equivalent to Rs 664.56 for 13.58 gm), which indicates the potential for a cost-effective method to produce pure DEP from Chlorella biomass.

3.
Artículo en Inglés | MEDLINE | ID: mdl-37950124

RESUMEN

Plastic waste is a rich source of hydrocarbons that can be converted into bio-oil through pyrolysis. In this study, bio-oil was produced by pyrolysis of waste-polypropylene using spent FCC catalyst. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that catalytically produced oil has the majority of compounds in the hydrocarbon range of C6-C18. The catalytic pyrolysis oil was blended with conventional fuel (diesel) to extensively investigate its suitability as a fuel substitute in a single-cylinder, four-stroke, 3.5 kW, diesel internal combustion (IC) engine. Furthermore, four fuels, i.e., CF100PO00 (pure diesel), CF90PO10 (10% v/v pyrolysis oil blended with diesel), CF85PO15 (15% v/v pyrolysis oil blended with diesel), and CF80PO20 (20% v/v pyrolysis oil blended with diesel), were tested in IC diesel engine for performance, combustion, and exhaust emission analysis at 1500 rpm. The tests were carried out at five loads, i.e., 1, 5, 10, 15, and 20 Nm. It was found that CF90PO10 produced 6.61% higher brake thermal efficiency (BTE), whereas CO2 exhaust emission decreased by 20% for CF80PO20 with respect to the pure diesel. Diesel blends with plastic pyrolysis oil can be a promising biofuel to improve engine performance and combustion characteristics without any significant engine modification.

4.
Physiol Mol Biol Plants ; 29(8): 1073-1079, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37829700

RESUMEN

We remember Dr Ajay Parida, a leading plant biotechnologist, whose premature passing has deprived the Indian plant science community of a committed scientist and an able administrator. Born on 12 December 1963 in Bhagabanpur, Cuttack District (now Jajpur district), Odisha, he passed away in Guwahati on 19 July 2022. A collegial scientist, his down-to-earth and approachable nature, as well as his resourcefulness were instrumental in advancing the cause of Indian science and harnessing frontier biotechnological tools as vehicles of social consciousness. His expertise in quantitative DNA variation and molecular marker analysis, paved the way for subsequent research on mangrove molecular diversity at the M. S. Swaminathan Research Foundation (MSSRF), Chennai. His contributions to mangrove biology, genetics and genomics as well as extremophile plant species in the Indian context over two decades are a benchmark in his field. He also provided commendable leadership in his capacity as Director, Institute of Life Sciences (ILS), Bhubaneshwar during the COVID-19 pandemic.

5.
Front Plant Sci ; 14: 1182074, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37731982

RESUMEN

Efficient regeneration of transgenic plants from explants after transformation is one of the crucial steps in developing genetically modified plants with desirable traits. Identification of novel plant growth regulators and developmental regulators will assist to enhance organogenesis in culture. In this study, we observed enhanced shoot regeneration from tomato cotyledon explants in culture media containing timentin, an antibiotic frequently used to prevent Agrobacterium overgrowth after transformation. Comparative transcriptome analysis of explants grown in the presence and absence of timentin revealed several genes previously reported to play important roles in plant growth and development, including Auxin Response Factors (ARFs), GRF Interacting Factors (GIFs), Flowering Locus T (SP5G), Small auxin up-regulated RNAs (SAUR) etc. Some of the differentially expressed genes were validated by quantitative real-time PCR. We showed that ticarcillin, the main component of timentin, degrades into thiophene acetic acid (TAA) over time. TAA was detected in plant tissue grown in media containing timentin. Our results showed that TAA is indeed a plant growth regulator that promotes root organogenesis from tomato cotyledons in a manner similar to the well-known auxins, indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA). In combination with the cytokinin 6-benzylaminopurine (BAP), TAA was shown to promote shoot organogenesis from tomato cotyledon in a concentration-dependent manner. To the best of our knowledge, the present study reports for the first time demonstrating the function of TAA as a growth regulator in a plant species. Our work will pave the way for future studies involving different combinations of TAA with other plant hormones which may play an important role in in vitro organogenesis of recalcitrant species. Moreover, the differentially expressed genes and long noncoding RNAs identified in our transcriptome studies may serve as contender genes for studying molecular mechanisms of shoot organogenesis.

6.
Eur J Orthod ; 45(6): 773-780, 2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-37499205

RESUMEN

OBJECTIVES: To assess the change in Oral Health-Related Quality of Life (OHRQoL) following orthodontic treatment using the Malocclusion Impact Questionnaire (MIQ) and to test the responsiveness of MIQ to treatment-associated changes. METHODS: A longitudinal prospective cohort study, in an orthodontic postgraduate centre, Kerala, India. Patients under 18 years were invited to complete the MIQ before the start of treatment (T0) and 1 month after treatment completion (T1). TheIndex of Orthodontic Treatment Need and Peer Assessment Rating (PAR) scores were assessed at both time periods as well as a global transition judgement at T1. RESULTS: Two hundred and ten participants were recruited and 162 completed both questionnaires (45.1% males; 54.9% females; age = 12-18 years, mean = 16.8; SD = 1.7). There was large reduction in MIQ scores from T0 (mean = 28.1, SD = 6.1) to T1 (mean = 3.7, SD = 2.6). 53% reported a large improvement in oral health and related life quality after treatment, 32% minimal change, and 15% no change. None reported worsening in OHRQoL at T1. There was a significant positive correlation between change in MIQ score and change in PAR score (r = 0.358), pretreatment aesthetic component (rho = 0.467) and dental health component (rho = 0.491) of the index of orthodontic treatment (IOTN-DHC), and treatment time (rho = 0.502). Regression analysis revealed the change in PAR score and pretreatment IOTN-DHC to be independent predictors of change in MIQ score. Standardized effect size (4.0) and standardized response mean (2.9) were large and the minimal important difference was 7.7. Receiver operating characteristic analysis reported a high diagnostic accuracy of MIQ. CONCLUSIONS: There was a significant improvement in OHRQoL following orthodontic treatment when assessed using a condition-specific measure for malocclusion. MIQ was found to be responsive to changes associated with orthodontic treatment.


Asunto(s)
Maloclusión , Calidad de Vida , Masculino , Femenino , Humanos , Adolescente , Niño , Estudios Prospectivos , Estudios Longitudinales , Salud Bucal , Estética Dental , Maloclusión/terapia , Encuestas y Cuestionarios
7.
Artículo en Inglés | MEDLINE | ID: mdl-37039915

RESUMEN

Waste marble powder (WMP) is a rich source of calcium and magnesium salts having an affinity for fluoride ions and therefore serves as a good defluoridation agent. Hydroxyapatite was synthesized from WMP generated by the marble processing industry to make an adsorbent for drinking water defluoridation. The synthesized marble hydroxyapatite (MA-Hap LR) powder was further formed into 2-3 mm pellets by extrusion spheronization technique using a polyvinyl alcohol binder. Continuous column defluoridation studies were conducted to obtain optimized column parameters such as input fluoride concentration, column inflow rates, optimum pellet size, and adsorbent bed parameters to obtain maximum fluoride adsorption capacity. The best breakthrough column performance was a maximum adsorption capacity of 1.21 mg/g, treating 10 mg/L fluoride concentration. The optimized column flow rate was at 1 LPH using an adsorbent bed height of 25 cm, which processed 28.5-bed volumes at an adsorbent exhaustion rate of 7.4 g/L. The column breakthrough performance data were fit into various kinetic models (Thomas model and Yoon-Nelson model) to describe adsorption kinetics and obtain correlation coefficients. Thomas's model fitted well with a high correlation coefficient value. Modelling studies indicate MA-Hap as a promising adsorbent for drinking water treatment, and optimum column design parameters were identified for scale-up for real applications.

8.
J Orthod ; 50(3): 276-286, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36922722

RESUMEN

AIM: The aim of the present study was to undertake a systematic review of the available evidence on the release of bisphenol-A (BPA) from thermoplastic materials used in the fabrication of clear aligners (CA). METHODS: Electronic databases, such as MEDLINE (via PubMed), Google Scholar, Scopus, Cochrane Library, Web of Science, OpenGrey, and the U.S. National Institute of Heath-Clinical Trials, were searched up to 27 October 2022. In vivo/in vitro studies that assessed the release of BPA from different thermoplastic CA materials, with or without a control group, were selected. The risk of bias (RoB) in the randomised controlled trials (RCT) and in vitro studies was assessed using the Cochrane RoB tool and the guidelines for the reporting of pre-clinical studies, respectively. The quality of evidence was determined using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) Pro tool. RESULTS: Six studies were considered for review from a total of 1926 records. This included one RCT and five in vitro studies. Only two studies found leaching of BPA, while four did not report any traces. The RoB was found to be moderate to high. The GRADE evidence level ranged from low to very low. Five of the included studies were conducted in vitro. Significant heterogeneity among the included studies prevented a quantitative synthesis. CONCLUSION: In light of the available conflicting evidence, BPA release from CAs can neither be confirmed nor denied. Safety remains questionable until high-quality in vivo trials prove otherwise. REGISTRATION: PROSPERO CRD42022310434.


Asunto(s)
Aparatos Ortodóncicos Removibles , Proyectos de Investigación , Humanos , Compuestos de Bencidrilo , Fenoles
9.
Front Genet ; 13: 997780, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36199575

RESUMEN

In the past 2 decades, small non-coding RNAs derived from tRNA (tsRNAs or tRNA derived fragments; tRFs) have emerged as new powerful players in the field of small RNA mediated regulation of gene expression, translation, and epigenetic control. tRFs have been identified from evolutionarily divergent organisms from Archaea, the higher plants, to humans. Recent studies have confirmed their roles in cancers and other metabolic disorders in humans and experimental models. They have been implicated in biotic and abiotic stress responses in plants as well. In this review, we summarize the current knowledge on tRFs including types of tRFs, their biogenesis, and mechanisms of action. The review also highlights recent studies involving differential expression profiling of tRFs and elucidation of specific functions of individual tRFs from various species. We also discuss potential considerations while designing experiments involving tRFs identification and characterization and list the available bioinformatics tools for this purpose.

10.
Environ Sci Pollut Res Int ; 29(57): 86439-86467, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35688984

RESUMEN

Calcium, with its excellent adsorptive property and higher permissible limits in the environment, emerges as an effective wastewater treatment earth metal. Most of the catalysts, photocatalysts, and adsorbents reported in the literature have heavy metal complex, which creates a leaching problem. Majorly, precursors used for the synthesis of heterogeneous catalysts for wastewater treatment are costly. Therefore, the use of such precursors would be not suitable and feasible approach from an economic point of view. This review work is focused on giving an overview of the utilisation of calcium-based catalysts (adsorbents and photocatalyst) for the removal/degradation of various types of dye water pollutants and summarises the reported effects of calcium as a base on the removal efficiency of dopants. In this article, an extensive literature survey is presented on the various photocatalysts developed and the different syntheses involved in their preparation. As the utilisation of marble powder is a green sustainable approach, the scope of various calcium-based photocatalysts and their application is presented. This article also aims for the elementary and inclusive determination of the effect of introducing calcium as a base for different catalysts and adsorbents.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Calcio , Polvos , Contaminantes Químicos del Agua/análisis , Carbonato de Calcio , Aguas Residuales
11.
J World Fed Orthod ; 11(3): 49-58, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35288033

RESUMEN

BACKGROUND: The objective was to provide a synthesis of the existing literature on the effectiveness of maxillary expansion in intercepting palatally displaced canines (PDCs). METHODS: Studies that evaluated the effectiveness of maxillary expansion in subjects with PDCs in the mixed dentition period were included. The following electronic databases were searched until November 30, 2021: MEDLINE (via PubMed), Scopus, Google Scholar, Web of Science, and Cochrane library. Grey literature search and manual search were also performed. The risk of bias was assessed using the Cochrane tool for the one randomized controlled trial (RCT) and the ROBINS-I tool for the non-RCTs. The data were extracted and meta-analysis was performed using RevMan 5.4. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach was used to assess the certainty of evidence. RESULTS: Four studies were selected from 9,586 records, which included one RCT and three non-RCTs. The former demonstrated a high risk of bias whereas the non-RCTs showed moderate risk. The meta-analysis of three non-RCTs found no significant improvement in the alpha angle of canines after rapid maxillary expansion, with a difference of -4.26 (95% CI -11.41 to 2.89; P = 0.24). The RCT showed an increase in the eruption rate of high-risk canines with rapid maxillary expansion. Slow maxillary expansion did not demonstrate any favorable change. The level of evidence ranged from low to very low. CONCLUSIONS: There is insufficient evidence to recommend the use of maxillary expansion as a stand-alone procedure in intercepting PDCs. Additional well-conducted trials are required.


Asunto(s)
Técnica de Expansión Palatina , Erupción Ectópica de Dientes , Diente Canino , Humanos , Ortodoncia Interceptiva/métodos , Hueso Paladar , Erupción Ectópica de Dientes/terapia , Extracción Dental/métodos
12.
Am J Orthod Dentofacial Orthop ; 161(5): 619-620, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35016811

RESUMEN

Clear aligner therapy has revolutionized orthodontic care delivery over the last 2 decades. With the increase in demand for clear aligner therapy, there is a concern about the plastic burden on the environment. Hence, we initiated research to investigate its environmental impact. This short communication aims to discuss the rationale of our ongoing study.


Asunto(s)
Aparatos Ortodóncicos Removibles , Humanos , Técnicas de Movimiento Dental
13.
Physiol Mol Biol Plants ; 26(1): 163-172, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32158127

RESUMEN

Salinization of soil is a prime abiotic stress that limits agriculture productivity worldwide. To Study the mechanisms that halophytes take up to survive under high salt condition is important in engineering salinity stress tolerance in sensitive species. Suaeda nudiflora is a halophyte plant that grows in the saline environment and extreme high tidal belt. The species have high capability to produce high protein biomass in salty soils due to C4 photosynthesis. The physiological and biochemical changes in S. nudiflora under salinity stress were studied by measuring chlorophyll content, electrolytic leakage, level of lipid peroxidation and total soluble sugars. Increased lipid peroxidation and electrolytic leakage was observed in salt stressed S. nudiflora compared to control plants. A suppression subtractive hybridization strategy was employed to identify differentially expressed genes under salt treatment in S. nudiflora. A total of 333 positive clones were identified and screened. Of these, 250 expressed sequence tags were identified. cDNA subtraction library resulted in 33 contigs and 138 singletons. The functional annotation and metabolic pathways identification were performed using the Blast2GO program. In addition, we analyzed the expression patterns of 18 genes associated with salt stress-responsive pathways by semi-quantitative PCR under salt and elevated carbon dioxide (CO2) conditions. Several of the analyzed genes showed an increase in expression levels under different time points of salt treatment and at different concentrations of salt. When the same genes were studied for its expression under elevated CO2 concentrations, most of the known salt responsive genes showed higher expression under the combined treatment of elevated CO2 concentrations (500 ppm) and NaCl treatment (200 mM) compare to ambient condition. This implies that salt responsive genes are enhanced at elevated CO2 concentrations.

14.
Ultrason Sonochem ; 58: 104692, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31450286

RESUMEN

This study describes the efficacy of the pretreatment method of tannery waste effluent (TWE) by hydrodynamic cavitation (HC) prior to anaerobic digestion (AD) using a slit venturi cavitating device operated at 5 bar pressure for 2 h. The HC effect caused faster disintegration and solubilization of larger organic molecules into smaller ones, so that it could be easily digested by the microbial cells resulting in higher degradation rates, lower acclimatization time, higher COD reduction of the TWE and higher biogas generation. The biogas yield and % COD reduction was almost twice higher in HC treated TWE compared to raw TWE. Biogas yield of 68.57 mL/g volatile solids with 43.17% COD reduction was obtained during AD of HC treated TWE in 2 L bioreactor with 10% seed dosage. 'AD' Simulator developed in MATLAB represented the AD performance for both raw and HC treated TWE feed and predicted for concentrations of organic polymers, monomers, VFA and biogas produced, in which model parameter optimization was done by validations using methane production data from bioreactors. The AD simulator estimated higher hydrolysis rate constants for HC treated TWE than for raw TWE as observed in the experiments. Biogas production increased up to 7.8 and 11.8 folds for raw and HC treated TWE samples respectively by adding food waste to TWE feed with organic loading rate of 48 h. Cost estimations proved that cost of excess biogas produced by anaerobic digestion of HC treated TWE mixed with food waste, recovers the extra cost of HC pretreatment when compared to raw TWE alone, establishing HC as an effective pre-treatment tool prior to AD.

15.
Langmuir ; 35(33): 10866-10876, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-31340119

RESUMEN

Curcumin is a natural polyphenol compound obtained from the turmeric plant, having numerous promising health benefits. To deliver curcumin into the human body, it is necessary to develop an efficient carrier system for its encapsulation such that the physicochemical properties of curcumin can be preserved during storage. In this study, the encapsulation stability, antioxidant activity, and release properties of curcumin encapsulated in the primary emulsion (PE: 0.0022% (w/w) curcumin, 9.99% (w/w) oil, 0.9% (w/w) whey protein isolate, pH 7) and secondary emulsion (SE: 0.00108% (w/w) curcumin, 4.90% (w/w) oil, 0.443% (w/w) WPI, 0.2% (w/w) sodium alginate, pH 5) prepared using ultrasonication were analyzed. It was observed that the formation of a double-layer coating of secondary biopolymer over the primary coated droplet enhanced the encapsulation efficiency and antioxidant activity of the curcumin during storage for 3 weeks. Moreover, the multilayer emulsions were freeze-dried to see the effect of dehydration of emulsion on the stability of multilayer-coated droplets. Fourier transform infrared analysis indicated the presence of all of the constituents, including curcumin, after the freeze drying of the emulsions. Scanning electron microscopy images showed that the microstructure of emulsion droplets was found to be uniformly distributed in the case of SE. The antioxidant activity of curcumin encapsulated in SE was found to be higher during storage, whereas it was significantly reduced in other encapsulated systems like PE, olive oil, and ethanol. In vitro release of curcumin from the multilayer emulsion was carried out under the simulated intestinal conditions of pancreatin enzyme and bile salt. Maximum releases of 71 and 63% were obtained in SE and PE, respectively, within 2 h of digestion. Overall, this study provides useful information on the formation of multilayer emulsion as a carrier system for the better protection and release of curcumin useful for food and pharmaceutical applications.


Asunto(s)
Antioxidantes , Curcumina , Ondas Ultrasónicas , Alginatos/química , Antioxidantes/química , Antioxidantes/farmacocinética , Curcumina/química , Curcumina/farmacocinética , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Emulsiones , Proteína de Suero de Leche/química
16.
J Hazard Mater ; 344: 1109-1115, 2018 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30216970

RESUMEN

Treatment of textile dyeing industry (TDI) effluent was investigated using hydrodynamic cavitation (HC) and in combination with advanced oxidation reagents such as air, oxygen, ozone and Fenton's reagent. Slit venturi was used as the cavitating device in HC reactor. The effects of process parameters such as inlet pressure, cavitation number, effluent concentration, ozone and oxygen flow rate, loading of H2O2 and Fenton's reagent on the extent of reduction of TOC, COD and color were studied. Efficiency of the hybrid treatment processes were evaluated on the basis of their synergetic coefficient. It was observed that almost 17% TOC, 12% COD, and 25% color removal was obtained using HC alone at inlet pressure of 5bar and pH of 6.8. The rate of reduction of TOC and COD decreased with dilution of the samples. HC in combination with Fenton's reagent (FeSO4·7H2O:H2O2 as 1:5) was most effective with reduction of 48%TOC and 38% COD in 15min and 120min respectively with almost complete decolorization (98%) of the TDI effluent. Whereas HC in combination with oxygen (2L/min) and ozone (3g/h) produced reduction of 48% TOC, 33% COD, 62% decolorization and 48% TOC, 23% COD, 88%, decolorization of TDI effluent respectively.

17.
Ultrason Sonochem ; 44: 299-309, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29680615

RESUMEN

In the present study, coagulation followed by cavitation was studied as a pretreatment tool for tannery waste effluent (TWE) with the aim of reducing its COD, TOC, TSS etc. and enhancing its biodegradability to make it suitable for anaerobic digestion. Initially, coagulation was applied to TWE using alum as a coagulant. The residual pH of treated effluent was found to be around pH of 4.5 where maximum COD and TSS reduction was achieved. In order to enhance the efficiency of pretreatment process, coagulated tannery waste effluent (CTWE) was further subjected to hydrodynamic cavitation (HC) and ultrasonication (US). In case of HC, effect of process parameters such as inlet pressure and dilution on the treatment of CTWE was initially investigated. Lower operating pressure (5 bar) was more favorable for the treatment of CTWE using HC in order to enhance the biodegradability index (BI) from 0.14 to 0.57 in 120 min. The CTWE samples when subjected to 50% dilution, HC pretreatment exhibited higher percentage and quantum reduction in TOC and COD. On the other hand, pretreatment of TWE using coagulation followed by US demonstrated that BI of effluent was enhanced from 0.10 to 0.41 in 150 min. Energy efficiency evaluation for all processes at their optimized conditions was done based on the actual amount of COD reduced per unit energy delivered to the system. Coagulation followed by HC for the pretreatment of TWE was found to be six times more energy efficient as compared to coagulation followed by US.

18.
Ultrason Sonochem ; 40(Pt A): 664-674, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28946471

RESUMEN

Marble waste powder consisting of calcium and magnesium compounds was used to synthesize a novel biocompatible product, marble apatite (MA) primarily hydroxyapatite (Hap) for applications in defluoridation of drinking water. Synthesis of marble apatite was carried out by using calcium compounds (mixture of hydroxide and nitrate) extracted from marble waste powder which was treated with potassium dihydrogen phosphate at 80°C under alkaline conditions using conventional precipitation method (CM) and ultrasonication method (USM). Qualitative analysis of synthesized marble apatite from both the methods was carried out using FTIR, phase analysis by XRD and microstructure analysis by SEM and TEM. When ultrasonication (USM) method was used, the yield of marble apatite was improved from 67.5% to 78.4%, with reduction in crystallite size (58.46nm), lesser agglomeration and comparatively well-defined spherical morphology compared to the CM method. Studies also include estimation of the defluoridation capacity of MA as an adsorbent for drinking water treatment and effects of process parameters such as pH, contact time, initial fluoride concentration, dosage and presence of other co-ions on fluoride removal capacity. The results showed that the experimental adsorption capacity of the marble apatite synthesized using USM method was significantly higher (1.826mg/g) than marble apatite synthesized using conventional method (0.96mg/g) at pH 7 with a contact time of 90min. The mechanism of adsorption was studied, and it was observed that Langmuir isotherm model fitted best to the experimental data, while the kinetic studies revealed that the process followed pseudo-second order model. This novel compound, marble apatite synthesized from marble waste powder is found to be promising for defluoridation of drinking water and will help in alleviating the problems of fluorosis as well as reduce the problems of disposal of marble waste.

19.
Ultrason Sonochem ; 37: 56-70, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28427668

RESUMEN

This research work presents the synthesis of hydroxyapatite (Hap) nanorods for defluoridation of drinking water by using both conventional (CM) and ultrasonication with precipitation (USPM) methods. Calcium nitrate was reacted with potassium phosphate in presence of ammonia for controlled pH to synthesize Hap nanorods, which was characterized using FTIR, XRD, SEM, TG-DTA, and TEM/EDS for determining its phase composition, structural and thermal decomposition behavior. When USPM method was used for synthesis, the yield of the Hap nanorods was improved from 83.24±1.0% to 90.2±1.0%, and complete phase transformation occurred with formation of elongated Hap nanorods. Effects of process parameters such as solution pH, contact time and adsorbent dose were studied through response surface methodology (RSM). A simple quadratic model was developed using Central Composite Design (CCD) and optimum parameters for fluoride adsorption process were determined to be pH 7, contact time 3h and adsorbent dose 7g/L for maximum removal capacity. Fluoride removal efficiency was predicted to be 93.64% which was very close to the experimental value obtained at 92.86% using ultrasonically prepared Hap. Fluoride adsorption isotherms fitted the Freundlich isotherm with an adsorption capacity of 1.49mg/g, while the kinetic studies revealed that the process followed pseudo-second order model. The treated water quality parameters such as residual fluoride, calcium leached, total hardness and alkalinity was investigated, and it was observed that all these parameters were within the permissible limits as per WHO and BIS standards.

20.
J Orthod Sci ; 6(1): 1-10, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28197396

RESUMEN

OBJECTIVE: To test the null hypothesis that there is no effect of esthetic perception of smiling profile in three different facial types by a change in the maxillary incisor inclination and position. MATERIALS AND METHODS: A smiling profile photograph with Class I skeletal and dental pattern, normal profile were taken in each of the three facial types dolichofacial, mesofacial, and brachyfacial. Based on the original digital image, 15 smiling profiles in each of the facial types were created using the FACAD software by altering the labiolingual inclination and anteroposterior position of the maxillary incisors. These photographs were rated on a visual analog scale by three panels of examiners consisting of orthodontists, dentists, and nonprofessionals with twenty members in each group. The responses were assessed by analysis of variance (ANOVA) test followed by post hoc Scheffe. RESULTS: Significant differences (P < 0.001) were detected when ratings of each photograph in each of the individual facial type was compared. In dolichofacial and mesofacial pattern, the position of the maxillary incisor must be limited to 2 mm from the goal anterior limit line. In brachyfacial pattern, any movement of facial axis point of maxillary incisors away from GALL is worsens the facial esthetics. The result of the ANOVA showed differences among the three groups for certain facial profiles. CONCLUSION: The hypothesis was rejected. The esthetic perception of labiolingual inclination and anteroposterior of maxillary incisors differ in different facial types, and this may effect in formulating treatment plans for different facial types.

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