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1.
J Environ Manage ; 297: 113253, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284329

RESUMO

Pyrolysis kinetics and thermodynamic parameters of two non-edible seeds, Pongamia pinnata (PP) and Sapindus emarginatus (SE), and their blend in the ratio of 1:1 (PS) were studied using the thermogravimetric analyzer. Kinetic triplets were determined using both model-free [Starink (STR), Friedman (FRM), Iterative Kissinger-Akahira-Sunose (IT-KAS), Iterative Ozawa-Flynn-Wall (IT-OFW), Vyazovkin (VYZ), and Master plot (MP)] and model fitting Coats-Redfern (CR) methods at three different heating rates 10, 30 and 50 °C/min. Activation energies were 192.66, 179.44, and 163.25 kJ/mol for PP, SE, and PS, respectively. It was found that the blend of the two-biomass (PS) showed promising results with lower activation energy compared to the individual biomass. Thermodynamic parameters (ΔG, ΔS, and ΔH) were obtained using the model-free isoconversional method. The three hidden layers of complex neuron topology are well fitted to the experimental DTG curves by artificial neural network (ANN). The study confirmed that the heating rate had a significant impact on the kinetics and thermodynamic parameters. The reaction mechanism was also in consonance with the experimental data. The study suggests that the PP and SE seeds can be an appropriate feed for pyrolysis, and their blend (PS) can be a viable alternative in optimizing the entire process.


Assuntos
Redes Neurais de Computação , Pirólise , Biomassa , Cinética , Termogravimetria
2.
J Prosthodont ; 22(5): 358-61, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23869850

RESUMO

PURPOSE: Heat-polymerized acrylic resins are used in dentistry for complete denture fabrication. Despite the polymerization method, conversion of monomer into polymer is often incomplete with free or unreacted residual monomer remaining in the polymerized resin. The aim of this study was to determine the amount of residual monomeric methyl methacrylate (MMA) leaching in the saliva of patients wearing complete dentures in their postinsertion period. MATERIALS AND METHODS: Thirty edentulous participants as first-time complete denture wearers (age 60 to 65 years) were selected. All the prostheses were fabricated using a similar standard technique with a heat-cured acrylic resin denture base material. Saliva samples were collected at time intervals of 1 hour, 1 day, and 3 days postdenture insertion. Participants were asked to discharge saliva every 30 seconds into a pre-weighed screw-capped container for a 5-minute period. MMA levels were measured using high performance liquid chromatography. Data were analyzed by ANOVA and Tukey-HSD. RESULTS: The maximum concentration of monomer released into saliva peaked 1 day after insertion of the complete dentures. The mean (SD) MMA content was 0.04 ± 0.01 (µg/ml) 1 hour after insertion, and 0.3 ± 0.09 (µg/ml), and 0.05 ± 0.01 (µg/ml) on the first and third days postinsertion, respectively. CONCLUSIONS: Although the released monomeric MMA was not at toxic levels, it could potentially sensitize complete denture patients or elicit an allergic reaction. The risk of the residual material as a primary irritant for a sensitizing reaction could be minimized by immersion of the denture in water for 24 hours before insertion.


Assuntos
Resinas Acrílicas/análise , Materiais Dentários/análise , Prótese Total , Metilmetacrilato/análise , Saliva/química , Resinas Acrílicas/química , Idoso , Cromatografia Líquida de Alta Pressão/métodos , Materiais Dentários/química , Bases de Dentadura , Planejamento de Dentadura , Difusão , Seguimentos , Temperatura Alta , Humanos , Metilmetacrilato/química , Pessoa de Meia-Idade , Boca Edêntula/reabilitação , Polimerização , Pressão
3.
Mhealth ; 9: 11, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37089270

RESUMO

Background: Rapid weight gain and overweight in infancy are associated with childhood obesity. Thus, effective, accessible interventions to promote healthy infant feeding practices to prevent early obesity are essential. Methods: This mixed-methods study involved diverse parents of infants in an urban, low-income pediatric clinic. Qualitative interviews explored parental attitudes towards feeding, early obesity, and communication with the pediatrician. A pilot, randomized controlled trial (RCT) informed by feedback provided by clinic parents compared text messages delivered for 12 months promoting healthy feeding practices to usual care to prevent early pediatric obesity. A computer-generated randomization schedule with balanced distribution for sex was used to place infants into groups. Weight-for-length percentiles and z-scores and feeding practices were measured at 0-2 weeks (baseline), 2-4 months, 6-9 months, and 12 months. Interviews were recorded, transcribed, and coded using thematic analysis. Weight for length percentile, Weight for length z scores, and feeding practices were compared between groups using repeated measures mixed analysis of variance (ANOVA). Results: Participants in the interviews were 15 parents of infants less than 1 month old. RCT participants were 38 parents of newborns (17 control; 21 intervention). Most parents in the qualitative evaluation viewed breastfeeding positively but also discussed barriers. Most also wanted practical information regarding infant feeding. There were no differences in weight-for-length percentile (F=0.52; P=0.60) or z-scores (F=0.7922; P=0.79), breastfeeding persistence χ2[1] =1.45, P=0.23, or age of introduction of solids in the intervention (statistical analysis not possible due to low counts) compared to the control group; however, low response to surveys limited the study's power. Conclusions: Text messaging has potential to extend the healthcare provider's communication beyond clinic. However, texting interventions should be flexible to mitigate barriers such as loss of phone service and challenges customizing messages to parent needs.

4.
Sarcoma ; 2021: 6633646, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744482

RESUMO

Intraoperative pathologic consultation plays an essential role in therapeutic decision making, possibly avoiding under or overtreatment of the patient. Common indications for intraoperative consultation include obtaining a diagnosis in an unknown pathology, ruling out malignancy, confirming a provisional diagnosis, and assessing margin status. Fifty patients undergoing surgery for soft tissue tumors or tumor-like lesions were included in the present prospective study to evaluate the role of intraoperative pathologic consultation by imprint and scrape cytology. Careful and quick gross examination of the specimen was performed, followed by processing for imprint and scrape smears. The prepared smears were evaluated by three pathologists and the cytological diagnosis compared subsequently with final histopathological diagnosis. Intraoperative consultation was primarily requested to make or confirm preoperative diagnosis. In 44.0% cases, no previous tissue/cytological diagnosis was available. In 56.0% cases, previous pathological diagnosis was available, but the reports were inconclusive or were reported from outside our institute. The diagnostic yield of imprint smears was 24% (5 malignant, 6 benign, and 1 inconclusive), and scrape smears was 100% (10 malignant, 38 benign, and 2 inconclusive). Paraffin-embedded sections yielded diagnosis in 100% cases (11 malignant, 38 benign, and 1 nonneoplastic). Imprint smears alone were not of much help in intraoperative diagnosis. Scrape smears were found to be superior to imprint smears in terms of diagnostic yield and accuracy. Combined imprint and scrape smear cytology did not provide any advantage in intraoperative provisional tissue diagnosis in soft tissue tumors.

5.
Prosthet Orthot Int ; 37(3): 245-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23045409

RESUMO

BACKGROUND: The great toe helps in maintaining body balance during standing, walking, running, dancing, and so on. CASE DESCRIPTION AND METHODS: A 22 year-old female patient reported to the department, one month after losing her left hallux in a road accident. Anatomical reconstruction was performed with distraction osteogenesis. The prosthesis was constructed using a wax pattern of the normal hallux to create a silicone prosthesis. The residual limb mold was altered to increase prosthesis retention. FINDINGS AND OUTCOMES: The procedure was economical, conserved materials, and produced lifelike anatomy without requiring artistic expertise. CONCLUSION: Distraction osteogenesis helped in improving function and retention of the prosthesis. Satisfactory esthetic and functional results were observed at the one-year follow-up. CLINICAL RELEVANCE: Distraction osteogenesis of the amputated hallux improved prosthetic prognosis by aiding retention. Modifications were made in the conventional prosthesis fabrication technique to increase retention, as the hallux is in constant movement and/or friction.


Assuntos
Amputados/reabilitação , Hallux/cirurgia , Osteogênese por Distração/métodos , Próteses e Implantes , Amputados/psicologia , Feminino , Seguimentos , Humanos , Prognóstico , Desenho de Prótese , Silicones , Resultado do Tratamento , Adulto Jovem
6.
J Biomed Mater Res B Appl Biomater ; 100(5): 1444-50, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22454327

RESUMO

Biocompatibility or tissue compatibility describes the ability of a material to perform with an appropriate host response when applied as intended. Poly-methylmethacrylate (PMMA) based resins are most widely used resins in dentistry, especially in fabrication of dentures and orthodontic appliances. They are considered cytotoxic on account of leaching of various potential toxic substances, most common being residual monomer. Various in vitro and in vivo experiments and cell based studies conducted on acrylic based resins or their leached components have shown them to have cytotoxic effects. They can cause mucosal irritation and tissue sensitization. These studies are not only important to evaluate the long term clinical effect of these materials, but also help in further development of alternate resins. This article reviews information from scientific full articles, reviews, or abstracts published in dental literature, associated with biocompatibility of PMMA resins and it is leached out components. Published materials were searched in dental literature using general and specialist databases, like the PubMED database.


Assuntos
Polimetil Metacrilato/efeitos adversos , Polimetil Metacrilato/química , Polimetil Metacrilato/uso terapêutico , Resinas Sintéticas/efeitos adversos , Resinas Sintéticas/química , Resinas Sintéticas/uso terapêutico , Humanos , PubMed
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