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1.
BMC Vet Res ; 19(1): 149, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37684611

RESUMO

BACKGROUND: The study aimed to investigate the effect of urea molasses mineral blocks (UMMB) on nutrient digestibility, productive performance and blood biochemical profile of indigenous yaks under various feeding systems. A total of sixteen yaks were randomly divided into four groups (n = 4 animal per group) and offered the, following feeding systems: (A) stall feeding, (B), urea molasses mineral block (UMMB) + stall feeding, (C) yard feeding and (D) UMMB + yard feeding. Trial lasted for 40 days. RESULTS: Results showed that nutrients intake (g) and nutrient digestibility (%) of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE) and crude fiber (CF) were significantly higher (p < 0.05) in stall and yard feeding groups with UMMB licking. Blood zinc, cobalt, hemoglobin (Hb), red blood cell (RBC), glucose and serum glutamate private transaminase (SGPT) significantly (p < 0.05) increased in stall and yard feeding with UMMB licking. Milk yield, Ca and monounsaturated fatty acid except milk composition improved significantly (p < 0.05) in stall and yard feeding groups with UMMB licking. CONCLUSION: It was concluded that feeding of UMMB improved utilization of low-quality roughages and best results were obtained from stall and yard feedings with UMMB licking as compared to other groups.


Assuntos
Melaço , Ureia , Animais , Bovinos , Minerais , Nutrientes , Eritrócitos
2.
J Environ Manage ; 319: 115690, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35834853

RESUMO

Due to the environmental and production problems of emulsion, it is important to efficiently separate oil-water emulsion to meet the refinery requirement and clean up oil spills. Synthesis of a universal demulsifier is not an easy task because the physical properties of crude oil vary, which makes its characterization and demulsification procedure difficult. To overcome this problem, hydrophilic and magnetically recoverable poly (methyl methacrylate-acrylic acid)/iron oxide magnetic composite nanoparticles ((P(MMA-AA)/Fe3O4 NPs) were developed as an efficient and economical demulsifier via soap-free emulsion polymerization. To characterize the magnetic composite NPs for their appropriate surface morphology and magnetic domain, TEM, FTIR, VSM, and TGA analyses were carried out. The newly synthesized NPs displayed good hydrophilic properties as they migrated quickly to the aqueous emulsion phase, which was also reassured by their water contact angle of 75°. They exhibit strong magnetic characteristics (20 amu/g) in the oil-water emulsion, makings the hydrophilic wettability capable and attractive to the external magnet. Experimental results revealed that the prepared magnetic composite NPs separated 99% of the water from stable emulsion in 30 min and could be recycled 8 times through magnetic separation. The recycled magnetic composite NPs maintain their hydrophilic wettability and efficiency in separating oil-water emulsion, making them economical and commercially viable. The migration of magnetic composite NPs to the aqueous phase in the stable emulsion with a strong magnetic domain explains the coalescence of emulsified water droplets and their quick separation from the stable emulsions through the external magnet.


Assuntos
Nanoestruturas , Água , Acrilatos , Emulsões , Compostos Férricos , Fenômenos Magnéticos , Metacrilatos , Metilmetacrilato , Óleos , Molhabilidade
3.
Arch Microbiol ; 202(6): 1449-1458, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32189018

RESUMO

Polymerases are enzymes that synthesize long chains or polymers of nucleic acids including DNA or RNA from nucleotides. They assemble nucleic acids by copying a DNA or RNA template strand using base-pairing interactions. One of the polymerase enzymes, Taq DNA polymerase, originally isolated from Thermus aquaticus (Taq) is a widely used enzyme in molecular biology so far. The thermostable properties of this enzyme have contributed majorly to the specificity, automation, and efficacy of the polymerase chain reaction (PCR), making it a powerful tool for today's molecular biology researches across the globe. The purification of Taq DNA polymerase from the native host results in low yield, more labor and time consumption. Therefore, many studies have been previously conducted to obtain this enzyme using alternative hosts. So far, all the existing methodologies are more laborious, time-consuming and require heavy expense. We used a novel approach to purify the enzyme with relatively high efficiency, yield and minimum time consumption using Escherichia coli (E. coli) as an alternative host. We cloned a 2500 base pair Taq DNA polymerase gene into pGEX-4T-1 vector, containing a GST-tag, downstream of tac promoter and overexpressed it using isopropyl ß-d-1-thiogalactopyranoside (IPTG) as an inducer. The enzyme was efficiently purified using novel chromatography approaches and was used in routine PCR assays in our laboratory. Our findings suggest a novel approach to facilitate the availability of polymerases for molecular and diagnostic studies. In the future, it may be used for the purification of other recombinant peptides or proteins used in structural biology and proteomics-based researches.


Assuntos
Clonagem Molecular/métodos , Escherichia coli/enzimologia , Taq Polimerase/genética , Taq Polimerase/metabolismo , Sequência de Bases , DNA Bacteriano/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica/genética , Nucleotídeos , Reação em Cadeia da Polimerase/métodos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Taq Polimerase/química
4.
Cochrane Database Syst Rev ; 3: CD004621, 2018 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-29517801

RESUMO

BACKGROUND: The permanent canine tooth in the maxillary (upper) jaw sometimes does not erupt into the mouth correctly. In about 1% to 3% of the population these teeth will be diverted into the roof of the mouth (palatally). It has been suggested that if the primary canine is removed at the right time this palatal eruption might be avoided. This is an update of a Cochrane review first published in 2009. OBJECTIVES: To evaluate the effect of extracting the primary maxillary canine on the eruption of the palatally ectopic maxillary permanent canine. SEARCH METHODS: We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 20 April 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 1), MEDLINE via OVID (1946 to 20 April 2012) and EMBASE via OVID (1980 to 20 April 2012). There were no restrictions regarding language or date of publication. SELECTION CRITERIA: Trials were selected if they met the following criteria: a randomised or quasi-randomised controlled trial, involving the extraction of the deciduous maxillary canine and assessing eruption/non-eruption of the palatally displaced maxillary permanent canine. DATA COLLECTION AND ANALYSIS: Data extraction was undertaken independently by two review authors. The primary outcome was the reported prevalence of eruption or non-eruption of the ectopic permanent canine into the mouth following observation or intervention. Results were to be expressed as risk ratios for dichotomous outcomes with 95% confidence intervals and mean differences for continuous outcomes. Heterogeneity was to be investigated, including both clinical and methodological factors. Authors of trials were contacted to request unpublished data. MAIN RESULTS: Reports of two randomised controlled trials previously excluded from an earlier version of the review due to "deficiencies in reporting, insufficient data" have now been included. These two trials included approximately 128 children, with more than 150 palatally displaced canine teeth, and both were conducted by the same research group. Data presented in the trial reports are either incomplete or inconsistent. Both trials are at high risk of bias. It must be emphasised that both trials have serious deficiencies in the way they were designed, conducted, and reported, and attempts to contact the authors to obtain detailed information and clarify inconsistencies have been unsuccessful. Allocation to treatment appears to be at the level of the individual, but outcomes of successful treatment relate to included teeth and data are not reported for each treatment group. Adverse effects are not reported. Neither trial provides any evidence to guide clinical decision making. AUTHORS' CONCLUSIONS: There is currently no evidence of the effects of extraction of primary canine teeth in 10-13 year old children with one or two palatally displaced permanent canine teeth.


Assuntos
Dente Canino/cirurgia , Maxila , Erupção Ectópica de Dente/prevenção & controle , Extração Dentária , Dente Decíduo , Dente não Erupcionado/prevenção & controle , Adolescente , Criança , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Cochrane Database Syst Rev ; 8: CD006966, 2017 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-28828758

RESUMO

BACKGROUND: Palatally displaced canines or PDCs are upper permanent canines, commonly known as 'eye' teeth, that are displaced in the roof of the mouth. This can leave unsightly gaps, cause damage to the surrounding roots (which can be so severe that neighbouring teeth are lost or have to be removed) and, occasionally, result in the development of cysts. PDCs are a frequent dental anomaly, present in 2% to 3% of young people.Management of this problem is both time consuming and expensive. It involves surgical exposure (uncovering) followed by fixed braces for two to three years to bring the canine into alignment within the dental arch. Two techniques for exposing palatal canines are routinely used in the UK: the closed technique and the open technique. The closed technique involves uncovering the canine, attaching an eyelet and gold chain and then suturing the palatal mucosa back over the tooth. The tooth is then moved into position covered by the palatal mucosa. The open technique involves uncovering the canine tooth and removing the overlying palatal tissue to leave it uncovered. The orthodontist can then see the crown of the canine to align it. OBJECTIVES: To assess the effects of using either an open or closed surgical method to expose canines that have become displaced in the roof of the mouth, in terms of success and other clinical and patient-reported outcomes. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 24 February 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (in the Cochrane Library, 2017, Issue 1), MEDLINE Ovid (1946 to 24 February 2017), and Embase Ovid (1980 to 24 February 2017). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: We included randomised and quasi-randomised controlled trials assessing young people receiving surgical treatment to correct upper PDCs. There was no restriction on age, presenting malocclusion or type of active orthodontic treatment undertaken. We included unilaterally and bilaterally displaced canines. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the results of the electronic searches, extracted data and assessed the risk of bias in the included studies. We attempted to contact study authors for missing data or clarification where feasible. We followed statistical guidelines from the Cochrane Handbook for Systematic Reviews of Interventions for data synthesis. MAIN RESULTS: We included three studies, involving 146 participants. Two studies were assessed as being at high risk of bias.The main finding of the review was that the two techniques may be equally successful at exposing PDCs (risk ratio (RR) 0.99, 95% confidence interval (CI) 0.93 to 1.06; three studies, 141 participants analysed, low-quality evidence).One surgical failure was due to detachment of the gold chain (closed group). One study reported on complications following surgery and found two in the closed group: a post-operative infection requiring antibiotics and pain during alignment of the canine as the gold chain penetrated through the gum tissue of the palate.We were unable to pool data for dental aesthetics, patient-reported pain and discomfort, periodontal health and treatment time; however, individual studies did not find any differences between the surgical techniques (low- to very low-quality evidence). AUTHORS' CONCLUSIONS: Currently, the evidence suggests that neither the open or closed surgical technique for exposing palatally displaced maxillary canine teeth is superior for any of the outcomes included in this review; however, we considered the evidence to be low quality, with two of the three included studies being at high risk of bias. This suggests the need for more high-quality studies. Three ongoing clinical trials have been identified and it is hoped that these will produce data that can be pooled to increase the degree of certainty in these findings.


Assuntos
Dente Canino/anormalidades , Erupção Ectópica de Dente/cirurgia , Estética Dentária , Humanos , Ortodontia Corretiva/métodos , Palato , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
6.
Am J Orthod Dentofacial Orthop ; 152(4): 509-515, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28962736

RESUMO

INTRODUCTION: Maxillary canines are generally considered important both cosmetically and functionally. Most claims on the importance of maxillary canines, however, have been based on expert opinions and clinician-based studies. There are no scientific studies in the literature reporting on their cosmetic importance or how laypeople perceive a smile treated by maxillary canine extractions. Our objective was to investigate whether there is any difference in the perceptions of patients' smiles treated by extracting either maxillary canines or first premolars, as judged by orthodontists, dentists, and laypeople. METHODS: This retrospective study included 24 participants who had unilateral or bilateral extraction of maxillary permanent canines and fixed appliances in the maxillary and mandibular arches to comprehensively correct the malocclusion, selected from orthodontic patients treated at Chesterfield Royal Hospital NHS trust in the United Kingdom over the last 20 years. The control group of patients had extraction of maxillary first premolars followed by fixed appliances and finished to an extremely high standard judged by the requirement that they had been submitted for the Membership in Orthodontics examination. The finished Peer Assessment Rating scores for this group were less than 5. The end-of-treatment frontal extraoral smiling and frontal intraoral views were presented for both groups. The photographs were blinded for extraction choice and standardized for size and brightness using computer software (Adobe Photoshop CC version 14.0; Adobe Systems, San Jose, Calif). The work file was converted to an editable pdf file and e-mailed to the assessors. The assessor panel consisted of 30 members (10 orthodontists, 10 dentists, and 10 laypeople), who were purposely selected. The measures were rated on a 10-point Likert scale. RESULTS: The attractiveness ratings were not statistically significantly different between the canine extraction and premolar extraction groups, with a mean difference of 0.33 (SD, 0.29) points. A 1-way repeated-measures analysis of variance to test the difference in scores among the laypeople, orthodontists, and dentists (n = 30) showed no statistically significant difference (Wilks lambda = 0.835; P = 0.138), and the Bonferroni test indicated that no pair-wise difference was statistically significant. CONCLUSIONS: No statistically significant difference was found in the smile attractiveness between canine extraction and premolar extraction patients as assessed by general dentists, laypeople, and orthodontists. Further high-quality studies are required to evaluate the effect of canine extraction and premolar substitution on functional occlusion.


Assuntos
Atitude do Pessoal de Saúde , Dente Canino/cirurgia , Estética Dentária , Sorriso , Extração Dentária , Feminino , Humanos , Masculino , Má Oclusão/terapia , Maxila , Ortodontia Corretiva , Estudos Retrospectivos
7.
Ann Hum Genet ; 79(2): 92-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25529316

RESUMO

Ectodermal dysplasias (EDs) belong to a group of genetic diseases which result from alterations in ectoderm-derived appendages including hair, nail, teeth and sweat glands. Ectodermal dysplasia syndactyly syndrome (EDSS1) is one of the rare forms of ED caused by mutations in nectin-4, encoded by the PVRL4 gene. The present study described clinical investigation of the EDSS1 identified in a large consanguineous family. Furthermore, DNA sequence analysis revealed a novel homozygous nonsense mutation (181C>T, p.Asp61*) in the PVRL4 gene.


Assuntos
Moléculas de Adesão Celular/genética , Códon sem Sentido , Displasia Ectodérmica/genética , Sindactilia/genética , Adulto , Consanguinidade , Análise Mutacional de DNA , Displasia Ectodérmica/patologia , Feminino , Humanos , Masculino , Paquistão
8.
Environ Sci Pollut Res Int ; 31(21): 30886-30901, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38619768

RESUMO

This study attempts to identify factors that significantly encourage the cessation of smoking in the context of Pakistan. The study distributes a modified questionnaire among 421 respondents (current as well as former smokers) in the capital city of Pakistan, Islamabad. The binary regression method was employed to data for analyzing predictors of making quit attempts and successful smoking cessation. The result indicates that respondents having strong intentions to quit, high socioeconomic status, low nicotine dependency, and past quit attempts, and those having no-smoking friends, are more likely to quit cigarette smoking successfully. On the other hand, factors like social pressure to quit smoking, religious information against smoking, intention to quit smoking, and public regulation on smoking are more likely to encourage smokers to make quit attempts. The study calls for community and school-wide smoking cessation campaigns involving officials, peers and parents, religious leaders, and other influential individuals to inform people about the dangers of smoking. In addition, religious leaders should be encouraged to issue rulings against smoking especially during "Friday Prayer." Furthermore, the government should pronounce more strict and comprehensive regulations on smoking by properly monitoring its implementation to encourage cessation of cigarette smoking.


Assuntos
Abandono do Hábito de Fumar , Fumar , Paquistão , Humanos , Fumar/epidemiologia , Masculino , Inquéritos e Questionários , Feminino , Adulto
9.
Environ Sci Pollut Res Int ; 30(60): 125138-125157, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37306879

RESUMO

Grid-based approaches render an efficient framework for data clustering in the presence of incomplete, inexplicit, and uncertain data. This paper proposes an entropy-based grid approach (EGO) for outlier detection in clustered data. The given hard clusters obtained from a hard clustering algorithm, EGO uses entropy on the dataset as a whole or on an individual cluster to detect outliers. EGO works in two steps: explicit outlier detection and implicit outlier detection. Explicit outlier detection is concerned with those data points that are isolated in the grid cells. They are either far from the dense region or maybe a nearby isolated data point and therefore declared as an explicit outlier. Implicit outlier detection is associated with the detection of outliers that are perplexedly deviated from the normal pattern. The determination of such outliers is achieved using entropy change of the dataset or a specific cluster for each deviation. The elbow based on the trade-off between entropy and object geometries optimizes the outlier detection process. Experimental results on CHAMELEON datasets and other similar datasets suggested that the proposed approach(es) detect the outliers more precisely and extend the capability of outliers detection to an additional 4.5% to 8.6%. Moreover, the resultant clusters became more precise and compact when the entropy-based gridding approach is applied on top of hard clustering algorithms. The performance of the proposed algorithms is compared with well-known outlier detection algorithms, including DBSCAN, HDBSCAN, RE3WC, LOF, LoOP, ABOD, CBLOF and HBOS. Finally, a case study for detecting outliers in environmental data has been carried out using the proposed approach and results are generated on our synthetically prepared datasets. The performance shows that the proposed approach may be an industrial-oriented solution to outlier detection in environmental monitoring data.


Assuntos
Algoritmos , Entropia , Análise por Conglomerados
10.
Nanomaterials (Basel) ; 13(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36770578

RESUMO

Conducting polymers integrated with metal oxides create opportunities for hybrid capacitive electrodes. In this work, we report a one-pot oxidative polymerization for the synthesis of integrated conductive polyindole/nickel oxide (PIn/NiO), polyindole/zinc oxide (PIn/ZnO), and polyindole/nickel oxide/zinc oxide (PNZ). The polymers were analyzed thoroughly for their composition and physical as well as chemical properties by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), and thermogravimetric analysis (TGA). The PIn and its composites were processed into electrodes, and their use in symmetrical supercapacitors in two- and three-electrode setups was evaluated by cyclic voltammetry (CV), galvanostatic discharge (GCD), and electrochemical impedance spectroscopy (EIS). The best electrochemical charge storage capability was found for the ternary PNZ composite. The high performance directly correlates with its uniformly shaped nanofibrous structure and high crystallinity. For instance, the symmetrical supercapacitor fabricated with PNZ hybrid electrodes shows a high specific capacitance of 310.9 F g-1 at 0.5 A g-1 with an energy density of 42.1 Wh kg-1, a power density of 13.2 kW kg-1, and a good cycling stability of 78.5% after 5000 cycles. This report presents new electrode materials for advanced supercapacitor technology based on these results.

11.
BMJ Open Qual ; 12(1)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36649943

RESUMO

AIMS AND OBJECTIVES: This study sets out to describe benefits from the implementation of electronic observation charting in intensive care units (ICU). This was an extension to the existing hospital wide digital health system. We evaluated error reduction, time-savings and the costs associated with conversion from paper to digital records. The world health emergency of COVID-19 placed extraordinary strain on ICU and staff opinion was evaluated to test how well the electronic system performed. METHODS: A clinically led project group working directly with programmers developed an electronic patient record for intensive care. Data error rates, time to add data and to make calculations were studied before and after the introduction of electronic charts. User feedback was sought pre and post go-live (during the COVID-19 pandemic) and financial implications were calculated by the hospital finance teams. RESULTS: Error rates equating to 219 000/year were avoided by conversion to electronic charts. Time saved was the equivalent of a nursing shift each day. Recurrent cost savings per year were estimated to be £257k. Staff were overwhelmingly positive about electronic charts in ICU, even during a health pandemic and despite redeployment into intensive care where they were using the electronic charts for the first time. DISCUSSION: Electronic ICU charts have been successfully introduced into our institution with benefits in terms of patient safety through error reduction and improved care through release of nursing time. Costs have been reduced. Staff feel supported by the digital system and report it to be helpful even during redeployment and in the unfamiliar environment of intensive care.


Assuntos
COVID-19 , Pandemias , Humanos , Saúde Global , Cuidados Críticos , Unidades de Terapia Intensiva
12.
Cochrane Database Syst Rev ; 12: CD004621, 2012 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-23235613

RESUMO

BACKGROUND: The permanent canine tooth in the maxillary (upper) jaw sometimes does not erupt into the mouth correctly. In about 1% to 3% of the population these teeth will be diverted into the roof of the mouth (palatally). It has been suggested that if the primary canine is removed at the right time this palatal eruption might be avoided. This is an update of a Cochrane review first published in 2009. OBJECTIVES: To evaluate the effect of extracting the primary maxillary canine on the eruption of the palatally ectopic maxillary permanent canine. SEARCH METHODS: We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 20 April 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 1), MEDLINE via OVID (1946 to 20 April 2012) and EMBASE via OVID (1980 to 20 April 2012). There were no restrictions regarding language or date of publication. SELECTION CRITERIA: Trials were selected if they met the following criteria: a randomised or quasi-randomised controlled trial, involving the extraction of the deciduous maxillary canine and assessing eruption/non-eruption of the palatally displaced maxillary permanent canine. DATA COLLECTION AND ANALYSIS: Data extraction was undertaken independently by two review authors. The primary outcome was the reported prevalence of eruption or non-eruption of the ectopic permanent canine into the mouth following observation or intervention. Results were to be expressed as risk ratios for dichotomous outcomes with 95% confidence intervals and mean differences for continuous outcomes. Heterogeneity was to be investigated, including both clinical and methodological factors. Authors of trials were contacted to request unpublished data. MAIN RESULTS: Reports of two randomised controlled trials previously excluded from an earlier version of the review due to "deficiencies in reporting, insufficient data" have now been included. These two trials included approximately 128 children, with more than 150 palatally displaced canine teeth, and both were conducted by the same research group. Data presented in the trial reports are either incomplete or inconsistent. Both trials are at high risk of bias. It must be emphasised that both trials have serious deficiencies in the way they were designed, conducted, and reported, and attempts to contact the authors to obtain detailed information and clarify inconsistencies have been unsuccessful. Allocation to treatment appears to be at the level of the individual, but outcomes of successful treatment relate to included teeth and data are not reported for each treatment group. Adverse effects are not reported. Neither trial provides any evidence to guide clinical decision making. AUTHORS' CONCLUSIONS: There is currently no evidence of the effects of extraction of primary canine teeth in 10-13 year old children with one or two palatally displaced permanent canine teeth.


Assuntos
Dente Canino/cirurgia , Maxila , Erupção Ectópica de Dente/prevenção & controle , Extração Dentária , Dente Decíduo , Dente não Erupcionado/prevenção & controle , Adolescente , Criança , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Nanomaterials (Basel) ; 12(4)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35214913

RESUMO

Fabrication of composites by developing simple techniques can be an efficient way to modify the desire properties of the materials. This paper presents a detailed study on synthesis of low cost and efficient nitrogen doped reduced graphene oxide nickle-silver (N-rGO-Ni/Ag) and nickel-cobalt (N-rGO-Ni/Co) nanocomposites as electrocatalysts in fuel cell using one-pot blended reflux condensation route. An admirable correlation in the structures and properties of the synthesized nanocomposites was observed. The Oxygen Reduction Reaction (ORR) values for N-rGO-Ni/Ag and N-rGO-Ni/Co calculated from the onset potential, using Linear Sweep Voltammetry (LSV), were found to be 1.096 and 1.146. While the half wave potential were determined to be 1.046 and 1.106, respectively, N-rGO-Ni/Ag and N-rGO-Ni/Co. The Tafel and bi-functional (ORR/OER) values were calculated as 76 and 35 mV/decade and 1.23 and 1.12 V, respectively, for N-rGO-Ni/Ag and N-rGO-Ni/Co. The lower onset and half wave potential, low charge transfer resistance (Rct = 1.20 Ω/cm2) and internal solution resistance (Rs = 8.84 × 10-1 Ω/cm2), lower Tafel values (35 mV), satisfactory LSV measurements and mass activity (24.5 at 1.056 V for ORR and 54.9 at 1.056 for OER) demonstrate the remarkable electrocatalytic activity of N-rGO-Ni/Co for both ORR and OER. The chronamperometric stability for synthesized nanocomposites was found satisfactory up to 10 h.

14.
Polymers (Basel) ; 14(2)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35054710

RESUMO

Electronically conducting poly (aniline-co-2-hydroxyaniline) (PACHA), a copolymer of aniline and 2-hydroxyaniline (2HA), was electrochemically coated on gold substrate for methanol electrooxidation in alkaline media. The electrochemical behavior of PACHA coated gold electrode towards methanol electrooxidation was investigated via cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) for application in an alkaline fuel cell. Methanol electrooxidation was observed at two different electrode potentials depending on the concentration of the base. At the PACHA coated gold electrode, the methanol oxidation peak was observed at lower overpotential (at 0.19 V) in a solution of high base concentration (1.8 M NaOH), which was 30 mV lower than the peak for the uncoated gold electrode. In addition, the Faradic current Imax obtained on the PACHA coated electrode (20 mA) was two times higher as compared to the Faradic current Imax of the un-modified gold electrode (10 mA). In solution of lower base concentration (0.06 M NaOH), the electrooxidation of methanol became sluggish on both electrodes, as indicated by peak shifting towards positive potential and with reduced faradaic current (at 0.74 V on PACHA coated electrode; Imax 10 mA). The electrooxidation of methanol at both lower and higher electrode potentials was analyzed mechanistically and discussed in light of the literature. EIS results were interpreted using Nyquist and Bode plots. The charge transfer resistance was decreased and pseudo-capacitive behavior changed to conductive behavior when external applied potential was increased from 0.1 V to 0.4 V.

15.
Polymers (Basel) ; 14(15)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35956630

RESUMO

The lack of an eco-friendly approach towards application of polyaniline as a coating material has been one of the most challenging tasks. Herein, the synthesis of green Prunus domestica gum grafted polyaniline (PDG-g-PANI) composite is reported by a cost-effective emulsion polymerization for application as an efficient anti-corrosion material for mild steel (MS) and stainless steel (SS) in a strong corroding environment. The composite formation was confirmed by Ultraviolet Visible (UV-Visible) and Fourier Transformed Infrared (FTIR) spectroscopies. X-ray diffraction data revealed the amorphous nature of the PDG-g-PANI. Scanning Electron Microscopic (SEM) images showed a bi-layered structure having a parent porous layer of PANI coated with afibrous layer of PDG. The solubility test confirmed the dissolution of PDG-g-PANI in common organic solvents such as acetone, ethanol, propanol, butanol, chloroform, N-Methyl-2-pyrrolidone, dimethyl sulfoxide, and the mixture of propanol and chloroform. The polarization curve, open circuit potential, electrochemical impendence spectroscopy (EIS), and gravimetric analysis were applied to investigate the corrosion protection behavior of the composite on MS and SS in 3.5% NaCl and 1 M H2SO4 solution. The PDG-g-PANI-coated MS exhibited 96% corrosion inhibition efficiency as compared to 86% and 43% for pristine PANI and PDG in 3.5% NaCl solution while PDG-g-PANI-coated SS showed 98% corrosion inhibition efficiency. Moreover, 99% and 96.6% corrosion protection was observed for PDG-g-PANI-coated MS and SS in 1 M H2SO4 solution. Gravimetric studies revealed that PDG-g-PANI coating can protect MS up to 93% for 14 days in salt solution while 97% corrosion inhibition efficiency was retained for 2 months in open air.

16.
Nanomaterials (Basel) ; 12(3)2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35159856

RESUMO

A polybenzopyrrole@nickel oxide (Pbp@NiO) nanocomposite was synthesized by an oxidative chemical one-pot method and tested as an active material for hybrid electrodes in an electrochemical supercapattery device. The as-prepared composite material exhibits a desirable 3D cross-linked nanostructured morphology and a synergistic effect between the polymer and metal oxide, which improved both physical properties and electrochemical performance. The unprocessed material was characterized by X-ray diffraction, FTIR and UV-Vis spectroscopy, scanning electron microscopy/energy disperse X-ray analysis, and thermogravimetry. The nanocomposite material was deposited without a binder on gold current collectors and investigated for electrochemical behavior and performance in a symmetrical two- and three-electrode cell setup. A high specific capacity of up to 105 C g-1 was obtained for the Pbp@NiO-based electrodes with a gravimetric energy density of 17.5 Wh kg-1, a power density of 1925 W kg-1, and excellent stability over 10,000 cycles.

17.
Front Psychol ; 13: 1039645, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36405169

RESUMO

Computer vision (CV) and human-computer interaction (HCI) are essential in many technological fields. Researchers in CV are particularly interested in real-time object detection techniques, which have a wide range of applications, including inspection systems. In this study, we design and implement real-time object detection and recognition systems using the single-shoot detector (SSD) algorithm and deep learning techniques with pre-trained models. The system can detect static and moving objects in real-time and recognize the object's class. The primary goals of this research were to investigate and develop a real-time object detection system that employs deep learning and neural systems for real-time object detection and recognition. In addition, we evaluated the free available, pre-trained models with the SSD algorithm on various types of datasets to determine which models have high accuracy and speed when detecting an object. Moreover, the system is required to be operational on reasonable equipment. We tried and evaluated several deep learning structures and techniques during the coding procedure and developed and proposed a highly accurate and efficient object detection system. This system utilizes freely available datasets such as MS Common Objects in Context (COCO), PASCAL VOC, and Kitti. We evaluated our system's accuracy using various metrics such as precision and recall. The proposed system achieved a high accuracy of 97% while detecting and recognizing real-time objects.

18.
Polymers (Basel) ; 14(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36501523

RESUMO

Eco-friendly inhibitors have attracted considerable interest due to the increasing environmental issues caused by the extensive use of hazardous corrosion inhibitors. In this paper, environmentally friendly PDG-g-PANI/Al2O3 composites were prepared by a low-cost inverse emulsion polymerization for corrosion inhibition of mild steel (MS) and stainless steel (SS). The PDG-g-PANI/Al2O3 composites were characterized by different techniques such as X-ray diffraction (XRD), UV/Vis, and FTIR spectroscopy. XRD measurements show that the PDG-g-PANI/Al2O3 composite is mostly amorphous and scanning electron micrographs (SEM) reveal a uniform distribution of Al2O3 on the surface of the PDG-g-PANI matrix. The composite was applied as a corrosion inhibitor on mild steel (MS) and stainless steel (SS), and its efficiency was investigated by potentiodynamic polarization measurement in a 3.5% NaCl and 1 M H2SO4 solution. Corrosion kinetic parameters obtained from Tafel evaluation show that the PDG-g-PANI/Al2O3 composites protect the surface of MS and SS with inhibition efficiencies of 92.3% and 51.9% in 3.5% NaCl solution, which is notably higher than those obtained with untreated epoxy resin (89.3% and 99.5%). In particular, the mixture of epoxy/PDG-g-PANI/Al2O3 shows the best performance with an inhibition efficiency up to 99.9% on MS and SS. An equivalent good inhibition efficiency was obtained for the composite for 1M H2SO4. Analysis of activation energy, formation enthalpy, and entropy values suggest that the epoxy/PDG-g-PANI/Al2O3 coating is thermodynamically favorable for corrosion protection of MS and exhibits long-lasting stability.

19.
Animals (Basel) ; 12(3)2022 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35158597

RESUMO

This study aimed to evaluate the impact of dietary addition of jojoba seed oil on productive performance, physicochemical attributes and carcass quality of broiler meat under tropical weather conditions. A total of 384 one-day-old Ross-308 were subdivided into four dietary treatments of jojoba seed oil: 0, 50, 100 and 150 mg/kg of control diet. Each treatment group included twelve replicates with eight birds each. The results showed that dietary supplementation of jojoba seed oil linearly increased (p < 0.01) feed intake, body weight gain and improved (p < 0.01) feed conversion ratio. Interestingly, diets supplemented with jojoba seed oil linearly (p < 0.05) improved the percentage of dressing and reduced abdominal fat percentage compared to the control group. Dietary supplementation of jojoba seed oil showed no effects (p ≥ 0.05) on the weight of internal organs, including liver, heart, gizzard, spleen and pancreas of broiler chickens. Increasing jojoba seed oil levels in the diet decreased (p < 0.001) percentages of cook and drip losses of breast and leg (drumstick and thigh) muscles of broilers. It was concluded that jojoba seed oil used as a feed additive up to 150 mg/kg improves growth performance and meat quality of broiler chickens in tropical weather conditions.

20.
Polymers (Basel) ; 13(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502922

RESUMO

Polybenzopyrrole (Pbp) is an emerging candidate for electrochemical energy conversion and storage. There is a need to develop synthesis strategies for this class of polymers that can help improve its overall properties and make it as suitable for energy storage applications as other well-studied polymers in this substance class, such as polyaniline and polypyrrole. In this study, by synthesizing Pbp in surfactant-supported acidic medium, we were able to show that the physicochemical and electrochemical properties of Pbp-based electrodes are strongly influenced by the respective polymerization conditions. Through appropriate optimization of various reaction parameters, a significant enhancement of the thermal stability (up to 549.9 °C) and the electrochemical properties could be achieved. A maximum specific capacitance of 166.0 ± 2.0 F g-1 with an excellent cycle stability of 87% after 5000 cycles at a current density of 1 A g-1 was achieved. In addition, a particularly high-power density of 2.75 kW kg-1 was obtained for this polybenzopyrrole, having a gravimetric energy density of 17 Wh kg-1. The results show that polybenzopyrroles are suitable candidates to compete with other conducting polymers as electrode materials for next-generation Faradaic supercapacitors. In addition, the results of the current study can also be easily applied to other systems and used for adaptations or new syntheses of advanced hybrid/composite Pbp-based electrode materials.

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