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1.
Nanotechnology ; 35(15)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38181443

RESUMO

Dynamic mechanical properties of the poly(ether-sulfone) (PES)/multi-walled carbon nanotube (MWCNT) nanocomposites manufactured by powder metallurgical route was discussed for the first time. The structural investigation of the nanocomposites was analysed by x-ray diffraction. At room temperature, both storage modulus and microhardness of the nanocomposites increased by more than 60% while the strengthening efficiency at higher temperatures is several-folds compared to that of neat PES. The nanocomposites exhibited better damping behaviour compared to neat PES. The Cole-Cole plot indicated a good interaction between the PES and the MWCNT. Moreover, the coefficient of reinforcement decreased by 42% while the degree of entanglement increased.

2.
Nanotechnology ; 35(33)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38763132

RESUMO

Novel nanocomposites of poly (ether-ketone) (PEK) reinforced with carbon-coated Nickel nanoparticles (CCNi) were synthesized through a sequential process involving cost-effective ball milling and hot compaction. Scanning electron microscopy revealed an excellent dispersion and a three-dimensional network of CCNi nanoparticles in the matrix, causing a significant improvement in the electrical conductivity and electromagnetic interference shielding effectiveness (SE). Carbon coating of about 5 nm thick over Ni nanoparticle probably helps in uniform dispersion, avoids its oxidation and reduces its agglomeration in the matrix. An exceptionally low percolation threshold of 2.1 vol.% CCNi was found, and eight-orders of magnitude enhancement in the dc-electrical conductivity was achieved. The highest dc- and ac-electrical conductivities achieved were more than 0.01 S cm-1at 5.89 vol.% CCNi nanoparticles content which were the highest values amongst reported Ni-filled polymer composites and comparable with those of carbon nanotubes filled PEK nanocomposites. Electromagnetic interference SE of the CCNi/PEK nanocomposites was measured in the X-band, and a total SE (SET) of 17.52 dB was obtained for 5.89 vol.% CCNi reinforced PEK nanocomposite.

3.
Nanotechnology ; 31(38): 385702, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32470961

RESUMO

High-performance polymer matrix nanocomposites based on poly(ether-sulfone) (PES) matrix reinforced with multi-walled carbon nanotubes (MWCNTs) were fabricated using planetary ball mill followed by hot pressing. Their electrical properties and the electromagnetic interference shielding effectiveness (EMI-SE) were investigated and discussed. A percolation threshold of about 0.65 vol% MWCNT was obtained. The electrical conductivity was increased by more than ten orders of magnitude at the percolation threshold and to approximately 0.01 S cm-1 at 6.67 vol% (or 10 wt%) MWCNT. This is a significant improvement. The highest EMI-SE of about 29-30 dB (both in the X-band and Ku-band) was obtained for the 6.67 vol% MWCNT filled nanocomposites with a thickness of 0.9 mm. The specific EMI-SE of these nanocomposites were found to be higher than the literature values. The thermal stability and the char yield (measured at 900 °C) of the nanocomposites were found to be more than 470 °C and 40.6%, respectively.

4.
Br J Anaesth ; 123(2): e328-e332, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30916030

RESUMO

BACKGROUND: Reported outcome benefits after surgical pleth index (SPI, GE Healthcare, Helsinki, Finland) guided anaesthesia are conflicting. One potential explanation may be the lack of evidence for the selection of meaningful SPI target values. A recently published trial found an SPI cut-off of 30 as a 'best-fit' to predict moderate-to-severe acute postoperative pain. This prospective trial was designed to validate this target and to investigate the influence of patient age on SPI in this context. METHODS: After ethics approval, 200 patients undergoing non-emergency surgery were enrolled. Data related to SPI, heart rate (HR), and mean arterial pressure (MAP) were recorded for the last 5 min of surgery, just before arousal. After admission to recovery, pain scores (numeric rating scale [NRS], 0-10) were obtained every 5 min for 15 min. RESULTS: The data of 196 patients were analysed. Receiver-operating curve analysis showed a cut-off SPI value of 29 to be the optimum intraoperative target to discriminate between NRS 0-3 and 4-10. This confirms the 'best fit' cut-off for SPI published previously. Though still superior to HR and MAP, the sensitivity and specificity of the SPI were only poor. Age had no influence on the predictive accuracy of SPI. CONCLUSIONS: An SPI of approximately 30 was confirmed as having the best sensitivity/specificity to predict moderate-to-severe pain in the postanaesthesia care unit. However, the predictive accuracy was overall poor and not influenced by patient age. CLINICAL TRIAL REGISTRATION: ACTRN12617001475336.


Assuntos
Frequência Cardíaca/fisiologia , Monitorização Intraoperatória/métodos , Dor Pós-Operatória/diagnóstico , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/fisiopatologia , Pletismografia , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Adulto Jovem
5.
Clin Anat ; 29(6): 729-37, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27038435

RESUMO

Analysis of receptor status has become standard procedure for assessing breast cancer patients. Estrogen causes epithelial proliferation in breast tissue via the estrogen receptor (ER). The progesterone receptor (PR) is also regulated by the estrogen gene. Analyzing ER and PR together gives information regarding the likely response of carcinoma patients to hormonal therapy. The aim of the present study was to record the expression patterns of ER and PR in normal mammary tissue in different age groups to provide reference data to facilitate histological diagnosis. Breast tissues from the upper outer quadrant of each side of 27 adult female cadavers were examined after H & E staining. ER and PR were identified and examined by immunohistochemistry. The percentage area occupied by parenchyma relative to stromal tissue was calculated in different age groups and was about 4:6, 3.5:6.5, 3:7, 2:8, and 1.5:8.5 in the 3rd, 4th and 5th, 6th, 7th, 8th and 9th, and 10th decades of life, respectively. Both ER and PR were present in all age groups and the numbers of both receptors were maximal during the 4th decade. The distribution and staining patterns for both ER and PR were recorded in different age groups. The contiguous pattern of ER, which is considered pathognomonic of breast carcinoma, was not seen except in one case in the 6th decade. Moderately stained ER and PR receptor sites predominated throughout. The study of normal breast tissue of similar age might provide comparisons that will help histopathologists to make clinical diagnoses from breast biopsies. Clin. Anat. 29:729-737, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Mama/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
6.
Malays J Pathol ; 38(3): 321-325, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28028304

RESUMO

Most cases of Zollinger-Ellison syndrome (ZES) are described in adults. It is a rare disorder in childhood. Most cases present with abdominal pain due to peptic ulceration and chronic diarrhoea not responding to general measures. The symptom complex is initially confused with other more common diseases, which lead to a delay in diagnosis. We present a rare case of a-12-year boy who initially presented with abdominal pain, diarrhoea, vomiting and progressive weight loss for over a two-year period before he was finally diagnosed as a case of ZES with the primary tumour in the pancreatic head and with multiple metastasis in both the liver and lymph nodes.


Assuntos
Síndrome de Zollinger-Ellison/complicações , Síndrome de Zollinger-Ellison/diagnóstico , Dor Abdominal/etiologia , Criança , Doença Crônica , Diarreia/etiologia , Humanos , Masculino , Vômito/etiologia , Redução de Peso
7.
J Food Sci Technol ; 51(4): 813-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24741181

RESUMO

Drying characteristics of paddy (long grain variety PR-118 procured from PAU, Ludhiana) in an integrated dryer using single as well as combined heating source was studied at different air temperatures. The integrated dryer comprises three different air heating sources such as solar, biomass and electrical. Drying of paddy occurred in falling rate period. It was observed that duration of drying of paddy from 22 to 13 % moisture content (w.b.) was 5-9 h depending upon the source of energy used. In order to select a suitable drying curve, six thin layer-drying models (Newton, Page, Modified Page, Henderson and Pabis, Logarithmic and Wang and Singh) were fitted to the experimental moisture ratio data. Among the mathematical models investigated, Wang and Singh model best described the drying behaviour of paddy using solar, biomass and combined heating sources with highest coefficient of determination (r (2)) values and least chi-square, χ (2), mean bias error (MBE) and root mean square error (RMSE) values. However, Page model adequately described the drying behavior of paddy using electrical heating source.

8.
J Clin Pharm Ther ; 37(6): 681-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22958105

RESUMO

WHAT IS KNOWN AND OBJECTIVES: The Food and Drug Administration (FDA) issued new organ-specific warning label requirements for over-the-counter (OTC) analgesic products in order to make consumers aware of the risk of liver damage when using acetaminophen. However, awareness of a health risk alone cannot ensure consumers' engagement in safe and preventive behaviour. In this study, we attempted to: (i) measure consumer risk perception of liver damage due to the OTC acetaminophen products and (ii) analyse the effectiveness of the new organ-specific warning label in improving consumer risk perception of liver damage and intention to perform protective behaviours while using OTC acetaminophen products. METHODS: This within-subject experimental study used a convenience sample of English-speaking adults visiting OTC segments of selected pharmacy stores in Houston. Participants were randomly exposed to the old and new warning labels and their respective risk perception (measured on a visual analogue scale, 0%, no risk, to 100%, extreme risk) and behavioural intention (measured on a 7-point Likert scale) were recorded using a validated, self-administered questionnaire. Descriptive statistics and non-parametric Wilcoxon signed-rank tests were performed using sas statistical software (v 9.2) at a priori significance level of 0.05. RESULTS AND DISCUSSION: Majority of participants (74.4%) were not aware of the new warnings; however, majority (67.8%) had prior knowledge of the risk. The mean risk perception score for the new warning label was found to be significantly higher (72.2% vs. 65.9%, P < 0.0001) than the old warning label. Similarly, the average intention score for the new warning label was significantly higher (5.06 vs. 4.86, P < 0.0001) than the old warning label. WHAT IS NEW AND CONCLUSION: The new warning label mandated by FDA is effective in improving consumer risk perception of potential liver damage and may encourage protective behaviour. However, future studies are essential to assess the impact of the new label on actual changes in consumer behaviour and subsequent reduction in acetaminophen-related morbidity and mortality.


Assuntos
Acetaminofen/efeitos adversos , Analgésicos não Narcóticos/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Informação de Saúde ao Consumidor/métodos , Rotulagem de Medicamentos , Adulto , Feminino , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Medicamentos sem Prescrição/efeitos adversos , Percepção , Risco , Estatísticas não Paramétricas , Inquéritos e Questionários , Estados Unidos , United States Food and Drug Administration
9.
Indian J Chest Dis Allied Sci ; 54(1): 41-3, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22779122

RESUMO

Benign bronchial stenosis is managed by surgical or bronchoscopic methods. Although surgical approach is definitive, it is technically demanding and is costlier than bronchoscopic treatment. Here, we report the case of a 27-year-old female patient with symptomatic benign bronchial stenosis of the left main bronchus. The stenosis was dilated successfully through a fibreoptic bronchoscope by electrocautery followed by balloon bronchoplasty and application of mitomycin-C. On follow up, there was no evidence of re-stenosis.


Assuntos
Broncopatias/terapia , Cateterismo , Eletrocoagulação , Adulto , Broncopatias/diagnóstico , Constrição Patológica/diagnóstico , Constrição Patológica/terapia , Feminino , Humanos , Mitomicina/uso terapêutico , Inibidores da Síntese de Ácido Nucleico/uso terapêutico
10.
Indian J Ophthalmol ; 69(2): 286-289, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33463575

RESUMO

Purpose: To assess ocular morbidity attributable to kites (patang) with emphasis on the cause, type and severity of the injury, complications, and final visual outcome. Methods: All the patients with a history of kite injury during months of Makar Sankranti for consecutive 6 years (2014-2019) were included in this study. A B-scan, orbital X-ray, and CT scan were performed for extensive ocular evaluation. Results: : Out of 68 patients with kite-related injury, 58 were male and 10 were female. Globe rupture (20), lid laceration (18), penetrating injury (9), wooden foreign body in the anterior or posterior chamber (7), superficial foreign body (4), hyphema (7), and vitreous hemorrhage (3) due to falling from height were noted. Factors associated with a poor final visual outcome in our study were poor initial visual acuity, globe rupture, intraocular foreign body, and development of endophthalmitis. Conclusion: Kites can cause serious preventable injuries mostly among pediatric males. The use of protective eyewear and public awareness can decrease ocular injury significantly.


Assuntos
Endoftalmite , Corpos Estranhos no Olho , Ferimentos Oculares Penetrantes , Criança , Corpos Estranhos no Olho/diagnóstico , Corpos Estranhos no Olho/epidemiologia , Corpos Estranhos no Olho/etiologia , Ferimentos Oculares Penetrantes/diagnóstico , Ferimentos Oculares Penetrantes/epidemiologia , Ferimentos Oculares Penetrantes/etiologia , Feminino , Humanos , Hifema , Masculino , Prognóstico , Estudos Retrospectivos , Acuidade Visual
11.
Br J Anaesth ; 115(4): 635, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26385674
13.
Br J Anaesth ; 115(2): 329-30, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26170367
14.
Int J Food Sci Nutr ; 61(1): 1-10, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19961353

RESUMO

Studies revealed that Stevia has been used throughout the world since ancient times for various purposes; for example, as a sweetener and a medicine. We conducted a systematic literature review to summarize and quantify the past and current evidence for Stevia. We searched relevant papers up to 2007 in various databases. As we know that the leaves of Stevia plants have functional and sensory properties superior to those of many other high-potency sweeteners, Stevia is likely to become a major source of high-potency sweetener for the growing natural food market in the future. Although Stevia can be helpful to anyone, there are certain groups who are more likely to benefit from its remarkable sweetening potential. These include diabetic patients, those interested in decreasing caloric intake, and children. Stevia is a small perennial shrub that has been used for centuries as a bio-sweetener and for other medicinal uses such as to lower blood sugar. Its white crystalline compound (stevioside) is the natural herbal sweetener with no calories and is over 100-300 times sweeter than table sugar.


Assuntos
Extratos Vegetais , Stevia/química , Edulcorantes , Animais , Humanos , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta , Ratos , Edulcorantes/farmacologia , Edulcorantes/uso terapêutico
15.
Indian J Chest Dis Allied Sci ; 52(3): 161-3, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20949736

RESUMO

In recent years successful bronchoscopic management of bronchopleural fistulas (BPFs) by locating its site and then blocking the leaking segment with any of the several agents available has gained recognition. It is now considered as an alternate mode of management of BPF. Here we present a case of non-resolving pneumothorax that was managed successfully using bronchoscopic glue (cyanoacrylate glue) instillation.


Assuntos
Fístula Brônquica/terapia , Broncoscopia , Doenças Pleurais/terapia , Fístula do Sistema Respiratório/terapia , Fístula Brônquica/diagnóstico , Cianoacrilatos/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Doenças Pleurais/diagnóstico , Fístula do Sistema Respiratório/diagnóstico , Adesivos Teciduais/administração & dosagem
19.
J Nanosci Nanotechnol ; 9(12): 6902-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19908696

RESUMO

The mechanical, thermal, and dielectric properties of novel high performance poly(ether-ether-ketone) (PEEK)/AIN nanocomposites were discussed. The stiffness of the nanocomposites was significantly improved in the glassy state as well as rubbery state. The coefficient of thermal expansion (CTE) of the nanocomposites was found substantially lower than that of pure PEEK. The glass transition temperature and melting temperature of the nanocomposites were increased significantly. The thermal stability and dielectric constant of the nanocomposites were increased slightly with AIN content. The significant improvement in the properties of the nanocomposites was attributed to the good adhesion between the AIN nanoparticles and the polymer matrix. The fabricated nanocomposite is very promising for use in electronics packaging substrate as an alternative substrate owing to its good thermal, mechanical and dielectric properties.

20.
J Orthop Surg (Hong Kong) ; 17(1): 23-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19398788

RESUMO

PURPOSE: To assess the outcome of unreamed intramedullary nailing through the lateralised entry point using oblique proximal and biplanar distal interlocking screws. METHODS: 15 men and 3 women aged 25 to 58 (mean, 37) years underwent unreamed intramedullary nailing with oblique proximal and biplanar distal interlocking screws for proximal third metaphyseal tibial fractures. The entry point was kept proximal to the tibial tuberosity and slightly lateral to midline. Proximal locking was at 45 degrees to the coronal and sagittal planes. Biplanar distal locking was in the coronal and sagittal planes. RESULTS: 16 patients had bone union within 20 (mean, 17; range, 14-27) weeks; 2 underwent dynamisation for delayed union. Three patients had valgus angulation of less than 5 degrees; 2 had a loss of terminal knee flexion; 3 had a loss of ankle dorsiflexion; and 3 had shortening of more than 0.5 cm. Functional outcomes were excellent in 13, good in 4, and fair in one patient. No patient endured neurovascular injury, compartment syndrome or implant failure. CONCLUSION: Unreamed intramedullary nailing with oblique proximal and biplanar distal interlocking screws for proximal third tibial fractures was effective in preventing malalignment.


Assuntos
Parafusos Ósseos , Fixação Intramedular de Fraturas/instrumentação , Fraturas da Tíbia/cirurgia , Adulto , Estudos de Coortes , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Estudos Retrospectivos , Fraturas da Tíbia/patologia , Fraturas da Tíbia/fisiopatologia , Resultado do Tratamento
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