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1.
Artículo | IMSEAR | ID: sea-221449

RESUMEN

Electrical Discharge Machine (EDM) parameters have a significant influence on machining characteristic like material removal rate (MMR) and tool wear rate (TWR). Inconel 718, which is widely used in the Medical, Marine, Architectural and food processing industries, is used as a work material. The tool electrode materials used are brass and copper. Experiments are conducted using face centered central composite design to determine the effects of process parameters like current rate, pulse on time, pulse off time and concentration of titanium carbide nano particle in dielectric fiuid. Based upon the experimental outcomes, the effect of brass and copper electrodes during electric discharge machining of Inconel 718 using nano particles mixed dielectric fiuid was investigated.

2.
Artículo | IMSEAR | ID: sea-226410

RESUMEN

Brass (Pittala) is a very popular and common metal alloy typically comprised of 66% copper and 34% zinc. Undoubtedly, it has a much longer history than Zinc. Ayurvedic treatises such as Charaka Samhita (2nd century BC) and Sushruta Samhita (3rd century BC) have mentioned some instruments used for various therapies and surgical procedures made of Pittala such as Jeevah-nirlekhana (tongue scarper), Vasti Netra etc. The original Sanskrit equivalent for brass was Riti, the word Pittala being subsequently adopted for it. In Kautilya Arthasastra (4th century) it is known as Arakuta. Pittala kills a large number of microorganisms within a few minutes to hours of contact. So, it is a good antifouling material. Its ethno-medicinal use is in Raktapitta, Krimi, Kushta and Pandu Roga. Probably, there is no available literary research study done on Pittala so far. Most of the information is obtained from Rasa Ratan Samuchchaya. Pittala Bhasma retains the property of both Tamra (copper) and Yashada (zinc). It has Tikta Rasa (bitter taste), and its Virya (temperament) is either Ushna (hot) or Sheeta (cold), which depends on the variety of Pittala and various drugs used in the process to make Bhasma. It appears from the thorough search of the process of Marana, that its Bhasma preparation is easier than Tamra.

3.
Poblac. salud mesoam ; 18(1)dic. 2020.
Artículo en Español | SaludCR, LILACS | ID: biblio-1386885

RESUMEN

Resumen Introducción: En este trabajo se propone identificar las brechas en la tasa de mortalidad infantil (TMI), según el nivel de instrucción de las madres en las seis provincias del noroeste argentino (NOA), una región que se caracteriza por poseer indicadores sociodemográficos rezagados respecto al total del país. Metodología: Para estimar las TMI según nivel de instrucción de las madres se emplea el método de Brass con la variante propuesta por Hill. Se utilizan los datos del censo argentino de 2010. Además, se simula el nivel actual de la mortalidad infantil de acuerdo con los indicadores obtenidos. Resultados: La brecha entre la TMI de las mujeres con bajo y alto nivel de instrucción es entre dos y tres veces mayor, mientras que es entre una y dos veces al comparar las de nivel medio con las de alto. Si estas brechas se aplican a las TMI oficiales del año 2017, más de 10 defunciones infantiles por cada mil nacidos vivos corresponderían a mujeres de nivel medio o bajo. Conclusiones: Existe una desigualdad en la mortalidad infantil en el NOA, de acuerdo con la educación de las madres. De esta realidad se no escapan otras regiones del país ni del mundo. Si bien las estadísticas vitales intentan relevar algunos determinantes sociales de la salud, particularmente el nivel educativo de las personas, esta fuente aún no permite su aprovechamiento en el diagnóstico y seguimiento de desigualdades. Los métodos indirectos pueden complementar, cuando no suplir estas deficiencias, aun considerando sus propias limitaciones.


Abstract Introduction: This paper aims at identifying the gap in the Infant Mortality Rate (IMR) according to the mothers' education level in six provinces of the Argentinean Northwest (NOA). This is a region that is characterized by having sociodemographic indicators that lag behind the rest of the country. Methodology: In order to estimate the IMR according to the mothers' education level, the Brass method with Hill's variant is applied using data from the 2010 census. Moreover, the current infant mortality rate is simulated according to the obtained indicators. Results: The gap between the IMR of women with a lower education level and those with a higher education level is twice or three times higher, whereas the gap considering women of a middle education level and those of the highest level varies between one and two. If these gaps were applied to the official IMR from 2017, more than 10 infant deaths per one thousand of children born alive would correspond to women with middle or low education level. Conclusions: There is inequality in the infant mortality in the NOA region according to the education level of mothers, which is far from other regions in the country or the world. Even if vital statistics attempt at revealing some social determinants of health, especially the education level, this source cannot yet be fully used in the diagnostic and follow-up of said inequalities. Indirect methods, considering their own limitations, can complement these deficiencies.


Asunto(s)
Humanos , Mortalidad Infantil , Educación de la Población , Argentina
4.
J Cancer Res Ther ; 2019 Oct; 15(5): 1042-1050
Artículo | IMSEAR | ID: sea-213475

RESUMEN

Objective: This study presents the dosimetric data taken with radiochromic EBT3 film with brass mesh bolus using solid water and semi-breast phantoms, and its clinical implementation to analyze the surface dose estimates to the chest wall in postmastectomy radiotherapy (PMRT) patients. Materials and Methods: Water-equivalent thickness of brass bolus was estimated with solid water phantom under 6 megavoltage photon beam. Following measurements with film were taken with no bolus, 1, 2, and 3 layers of brass bolus: (a) surface doses on solid water phantom with normal incidence and on curved surface of a locally fabricated cylindrical semi-breast phantom for tangential field irradiation, (b) depth doses (in solid phantom), and (c) surface dose measurements around the scar area in six patients undergoing PMRT with prescribed dose of 50 Gy in 25 fractions. Results: Water-equivalent thickness (per layer) of brass bolus 2.09 ± 0.13 mm was calculated. Surface dose measured by film under the bolus with solid water phantom increased from 25.2% ±0.9% without bolus to 62.5% ± 3.1%, 80.1% ± 1.5%, and 104.4% ± 1.7% with 1, 2, and 3 layers of bolus, respectively. Corresponding observations with semi-breast phantom were 32.6% ± 5.3% without bolus to 96.7% ± 9.1%, 107.3% ± 9.0%, and 110.2% ± 8.7%, respectively. A film measurement shows that the dose at depths of 3, 5, and 10 cm is nearly same with or without brass bolus and the percentage difference is <1.5% at these depths. Mean surface doses from 6 patients treated with brass bolus ranged from 79.5% to 84.9%. The bolus application was discontinued between 18th and 23rd fractions on the development of Grade 2 skin toxicity for different patients. The total skin dose to chest wall for a patient was 3699 cGy from overall treatment with and without bolus. Conclusions: Brass mesh bolus does not significantly change dose at depths, and the surface dose is increased. This may be used as a substitute for tissue-equivalent bolus to improve surface conformity in PMRT

5.
Rev. bras. estud. popul ; 35(1): e0052, 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-985276

RESUMEN

Abstract Adolescent fertility -fertility rates at ages 15-19- fell substantially (around 30 percent) between 2000 and 2010. It was the first time Brazil experienced such a decline in those ages since 1970, when the census included one question about children born in the past 12 months. This phenomenon has an important implication for the P/F Brass ratio technique: it underestimates the cumulated current fertility up to age group 20-24 (F2), considering this cohort's previous fertility experience. Therefore, the P2/F2 value, used as an adjustment factor for the reported fertility level, is significantly overestimated. This paper discusses this issue and proposes an alternative to correct the reference period error in the 2010 Demographic Census in Brazil. The results of applying the proposed alternative in this specific context were very similar to those obtained using different techniques, thus supporting the strength of our alternative.


Resumo O Brasil experimentou, entre 2000 e 2010, pela primeira vez desde 1970, quando se introduziu o quesito sobre filhos nascidos vivos nos 12 meses anteriores à data de referência do censo, queda significativa (em torno de 30%) das taxas específicas de fecundidade declarada das mulheres entre 15 e 19 anos (f*1). Esse fenômeno tem uma importante consequência para a aplicação da técnica P/F de Brass: gera um erro, por falta, na fecundidade corrente acumulada até o grupo etário de 20 a 24 anos (F2), se tomada como experiência pregressa dessa coorte, levando a um valor de P2/F2, usado para ajustar o nível da fecundidade declarada, significativamente sobrestimado. O presente trabalho discute detalhadamente este problema e, por fim, propõe uma alternativa para se corrigir o erro de período de referência da fecundidade corrente do Censo Demográfico de 2010 do Brasil. A alternativa proposta, neste contexto específico, gerou estimativas de taxa de fecundidade total muito próximas às produzidas por outras técnicas.


Resumen Por la primera vez desde 1970 —cuando se introdujo la pregunta sobre nacidos vivos en los 12 meses anteriores a la fecha de referencia del censo— Brasil experimentó, entre 2000 y 2010, una disminución significativa de aproximadamente 30% de las tasas específicas de fecundidad declarada de mujeres entre 15 y 19 años (f*1). Este fenómeno trae una consecuencia importante para la aplicación de la técnica P/F de Brass: genera un error por falta en la fecundidad actual acumulada para el grupo de edad de 20 a 24 años (F2), lo que concomitantemente provoca una significativa sobrestimación en el valor de P2/F2 —utilizado para corregir el nivel de la fecundidad declarada—. Este trabajo discute este problema y propone finalmente una adaptación de la técnica original de Brass para aplicarla a los datos del censo de 2010. La alternativa propuesta generó, en este contexto específico, estimaciones de la tasa global de fecundidad similares a las producidas por otras técnicas.


Asunto(s)
Humanos , Demografía , Tasa de Natalidad , Adolescente , Censos , Fertilidad , Brasil , Interpretación Estadística de Datos , Nacimiento Vivo
6.
Annals of Clinical Microbiology ; : 80-85, 2018.
Artículo en Coreano | WPRIM | ID: wpr-718744

RESUMEN

BACKGROUND: The aim of this study was to comparatively evaluate the bactericidal effects of copper, brass (copper 78%, tin 22%), and stainless steel against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecium (VREFM), and multidrug-resistant Pseudomonas aeruginosa (MRPA). METHODS: The isolates (MRSA, VREFM, MRPA) used in this study were mixed wild type 3 strains isolated from patients treated at Uijeongbu St. Mary's Hospital in 2017. These strains showed patterns of multidrug resistance. The lyophilized strains were inoculated into and incubated for 24 hr in tryptic soy broth at 35℃. The initial bacterial inoculum concentration was adjusted to 105 CFU/mL. A 100-mL bacterial suspension was incubated in containers made of brass (copper 78%, tin 22%), copper (above 99% purity), and stainless steel at 35℃. Viable counts of bacteria strains were measured for 9 days. RESULTS: In this study, the bactericidal effects of copper and brass on MRSA, VREFM, and MRPA were verified. The bactericidal effect of stainless steel was much weaker than those of copper and brass. The bactericidal effect was stronger on MRPA than on MRSA or VREFM. CONCLUSION: To prevent cross infection of multidrug resistant bacteria in hospitals, further studies of longer duration are needed for testing of copper materials on objects such as door knobs, faucets, and bed rails.


Asunto(s)
Humanos , Bacterias , Cobre , Infección Hospitalaria , Resistencia a Múltiples Medicamentos , Enterococcus faecium , Staphylococcus aureus Resistente a Meticilina , Pseudomonas aeruginosa , Acero Inoxidable , Estaño
7.
Journal of University of Malaya Medical Centre ; : 26-30, 2017.
Artículo en Inglés | WPRIM | ID: wpr-732129

RESUMEN

Introduction: Recent compensators are commonly applied in IMRT. The precise properties of applied compensators such as thickness, attenuation coefficient and build up factor are intensively important for IMRT calculations. Method: The brass compensator used for 6 MV photon beam was studied to estimate the relative effect of thickness and field size on IMRT calculations. Various field size together with several compensator thicknesses were examined. Result: The average reduction of effective attenuation coefficient (EAC), for the fields of 10×10 cm2 to 20×20 cm2, was 9.94%. By increasing the field size, EAC was decreased. The major reduction of EAC due to increasing field size was found to be 9.62%. The build up factor was increased by 2% to 21.8% respect to field size and compensator thickness. Also, the build up factor was increased by adding up the thickness. The rate of changes ranged from 24% to 48 %.Conclusion: The compensator thickness and field size are significantly important to calculate the effective attenuation coefficient and build up facto

8.
Artículo en Inglés | IMSEAR | ID: sea-154599

RESUMEN

Statement of Problem: Given that meticulous implant prosthodontic procedures are recommended to obtain the best possible intraoral fit, the die systems used for multi implant casts warrant further investigation. Die stone expansion and errors introduced by removable die casts may exceed the accuracy required for the passive fit of implant prosthesis. Purpose: The purpose of the study was to evaluate the linear dimensional accuracy between the implant master die and three conceptually different die systems such as Pindex system, Accu-trac precision die system, and Conventional brass dowel pin system. Materials and Methods: Thirty impressions of implant master die were made with polyether impression material. Ten experimental implant casts were fabricated for each of the three different die systems tested: Accu-trac precision die tray system, Pindex system, and conventional brass dowel pin system. The solid experimental casts were sectioned and then removed from the die system 30 times. Linear distances between all six possible distances were measured from one centre of the transfer coping to the other, using a co-ordinate measuring machine in millimeters up to accuracy of 0.5 microns. Data were tabulated and statistically analyzed by Binomial non parametric test using SPSS version 15. Results: Significant differences were found for distance A-B (P = 0.002), A-C ( P = 0.002), A-D (P value = 0.002), and B-D ( P = 0.021) in Conventional Dowel pin system however for Accu-trac precision die tray system, it was significant only for distance A-D (P = 0.002) but for Pindex system it was non-significant for all the distances measured. Conclusion: Within the limitations of this study, use of Pindex system is recommended when sectioned dies are needed for a multi implant retained prosthesis.


Asunto(s)
Técnica de Colado Dental/instrumentación , Implantes Dentales , Técnica de Impresión Dental , Modelos Dentales , Tecnología Odontológica
9.
Artículo en Inglés | IMSEAR | ID: sea-174415

RESUMEN

Fixed Orthodontic Treatment involves the use of applinces with many metallic components. Some times appliance parts may go missing between appointments instead of and may be noticed during recall appointments. Ingestion of this parts is rare but if it happens it may be life threatening. Herewith a case of ingestion of metallic brass wire ligature and timely intervention is discussed.

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