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1.
Phys Rev E ; 108(3-2): 035209, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37849111

RESUMEN

Laser-direct-drive fusion target designs with solid deuterium-tritium (DT) fuel, a high-Z gradient-density pusher shell (GDPS), and a Au-coated foam layer have been investigated through both 1D and 2D radiation-hydrodynamic simulations. Compared with conventional low-Z ablators and DT-push-on-DT targets, these GDPS targets possess certain advantages of being instability-resistant implosions that can be high adiabat (α≥8) and low hot-spot and pusher-shell convergence (CR_{hs}≈22 and CR_{PS}≈17), and have a low implosion velocity (v_{imp}<3×10^{7}cm/s). Using symmetric drive with laser energies of 1.9 to 2.5MJ, 1D lilac simulations of these GDPS implosions can result in neutron yields corresponding to ≳50-MJ energy, even with reduced laser absorption due to the cross-beam energy transfer (CBET) effect. Two-dimensional draco simulations show that these GDPS targets can still ignite and deliver neutron yields from 4 to ∼10MJ even if CBET is present, while traditional DT-push-on-DT targets normally fail due to the CBET-induced reduction of ablation pressure. If CBET is mitigated, these GDPS targets are expected to produce neutron yields of >20MJ at a driven laser energy of ∼2MJ. The key factors behind the robust ignition and moderate energy gain of such GDPS implosions are as follows: (1) The high initial density of the high-Z pusher shell can be placed at a very high adiabat while the DT fuel is maintained at a relatively low-entropy state; therefore, such implosions can still provide enough compression ρR>1g/cm^{2} for sufficient confinement; (2) the high-Z layer significantly reduces heat-conduction loss from the hot spot since thermal conductivity scales as ∼1/Z; and (3) possible radiation trapping may offer an additional advantage for reducing energy loss from such high-Z targets.

2.
Am Surg ; 89(9): 3732-3738, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37148273

RESUMEN

INTRODUCTION: Despite a high prevalence of retained bullet fragments (RBFs) after firearm related injury (FRI) there is limited data on the full spectrum of their consequences, particularly the psychological impacts on those injured. Further, the experiences of FRI survivors with RBFs are missing from existing literature. The objective of this study was to explore the psychological impacts of RBFs on individuals who have experienced recent FRI. METHODS: Adult (18-65 years) survivors of FRI with radiographically confirmed RBFs were purposively selected from an urban Level 1 trauma center in Atlanta, Georgia, to participate in an in-depth interview. Interviews were conducted between March 2019 and February 2020. Thematic analysis was used to identify a range of psychological effects from RBFs. RESULTS: Interviews from 24 FRI survivors were analyzed: the majority of participants were Black males (N = 22, 92%) with a mean age of 32 years whose FRI occurred ∼8.6 months prior to data collection. The psychological effects of RBFs were grouped into four categories: physical health (eg, pain, limited mobility), emotional well-being (eg, anger, fear), social isolation, and occupational welfare (eg, disability leading to inability to work). A range of coping mechanisms were also identified. CONCLUSION: Survivors of FRI with RBFs experience a range of psychological impacts that are far-reaching and affect daily activities, mobility, pain and emotional wellbeing. Study results indicate a need for enhanced resources to support those with RBFs. Further, changes to clinical protocols are warranted on removal of RBFs and communication about the effects of leaving RBFs in situ.


Asunto(s)
Adaptación Psicológica , Dolor , Adulto , Masculino , Humanos , Miedo , Aislamiento Social , Sobrevivientes/psicología
5.
Semin Oncol ; 2022 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-35305831

RESUMEN

Lung cancer (both adenocarcinoma and squamous cell) progress through a series of pre-malignant histologic changes before the development of invasive disease. Each of these carcinogenic cascades is defined by genetic and epigenetic alterations in pulmonary epithelial cells. Additionally, alterations in the immune response, progenitor cell function, mutational burden, and microenvironmental mediated survival of mutated clones contribute to the risk of pre-malignant lesions progressing to cancer. Medical preventions studies have been completed and current and future trials are informed by the improved understanding of pre-malignancy. This will lead to precision chemoprevention trials based on lesional biology and histologic characteristics.

7.
Anal Chim Acta ; 1191: 339295, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35033239

RESUMEN

A methodology has been developed for the complete compositional characterization of lithium titanate (LTO) using neutron activation, which is quite challenging and no literature report is available so far. The concept of thermal neutron induced in-situ chain reactions 6Li(n,α)3H and 16O(3H,n)18F has been used for the determination of Li and O through the measurement of 18F activity. The method is capable of analyzing Li and O in percentage level as reported in the present analysis of two types of lithium titanate samples. Spectroscopic interference of the elements which can directly or indirectly affect the outcome, were evaluated meticulously. Determination of Ti was carried out using fast neutron activation through the product isotopes like 47Sc, 48Sc, generated via (n,p) nuclear reactions. Fast neutron activation methodology seems to be advantageous for Ti determination over thermal neutron activation, as it offers self validation through different isotopes and multiple gamma lines.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Neutrones Rápidos , Isótopos , Litio , Neutrones
8.
Clin Epigenetics ; 13(1): 149, 2021 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-34325733

RESUMEN

BACKGROUND: There is a growing interest in the role of brain-derived neurotrophic factor (BDNF) in major depressive disorder (MDD). BDNF potentially exhibits opposite effects in the pathways linked to anhedonia and reward learning on the one hand and cognitive performance, on the other hand. However, the epigenetic mechanisms behind this remain unknown. In the present study, we aimed to investigate the interplay of DNA methylation of different BDNF exons and the common Val66Met polymorphism on anhedonia, reward learning and cognitive performance in MDD. METHODS: We recruited 80 depressed patients and 58 age- and gender-matched healthy controls. Participants underwent clinical assessment including neuropsychological testing and a probabilistic reward task to assess reward learning. Val66Met polymorphism and DNA methylation of BDNF promoters I, IV and exon IX were assessed from whole blood derived DNA, using pyrosequencing. RESULTS: BDNF promoter I methylation was lower in MDD patients (p = 0.042) and was negatively associated with self-reported anhedonia. In depressed patients, both Val66Met polymorphism and DNA methylation of promoter I were significantly associated with reward bias (p < 0.050 and p = 0.040, respectively), without an interaction effect. On the other hand, methylation of exon IX had a negative impact on executive functioning (p = 0.002) and mediated the effect of Val66Met on this outcome in patients with MDD. CONCLUSIONS: Our results provide the first evidence of Val66Met susceptibility to differential epigenetic regulation of BDNF exons in reward learning and executive functioning in MDD, which needs to be further explored.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/análisis , Cognición , Trastorno Depresivo Mayor/genética , Adulto , Bélgica , Factor Neurotrófico Derivado del Encéfalo/genética , Metilación de ADN/genética , Metilación de ADN/fisiología , Trastorno Depresivo Mayor/epidemiología , Femenino , Humanos , Aprendizaje , Masculino , Persona de Mediana Edad , Psicometría/instrumentación , Psicometría/métodos
9.
Vet World ; 13(11): 2364-2370, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33363328

RESUMEN

Mastitis in dairy cattle is the most common management disorder that causes higher economic losses by lowering production and quality of milk leads to substantial economical loss. The aim of this article was to review worldwide important advances in strategies to control mastitis for production augmentation in dairy cattle. Many scientists worked to identify effective strategies to control mastitis caused by Streptococcus agalactiae, Staphylococcus aureus, and others. It is necessary to identify mechanisms of infection, define clinical and subclinical states of disease, determine exposure time, and identify pathogen-specific characteristics. Evolvement of management strategies that incorporated hygienic procedures (animal, floor, and milkman), post milking standing period of animal and strategic use of antibiotic or herbal therapy at dry-off, nutritional supplementation, fly control, body condition score optimization, etc., resulted in widespread control of mastitis. The udder, teat of animal, scientific management of milking, automatic milking procedure, genetic selection are considered as important factors to control mastitis. As farm management changed, scientists were directed to redefine control of mastitis caused by opportunistic pathogens of environmental sources and have sought to explore management strategies which will maintain animal well-being in a judicial way. Although significant advances in mastitis management have been made changing herd structure, changing climatic scenario and more rigorous milk processing standards ensure that mastitis will remain important issue for future research.

11.
Inorg Chem ; 59(6): 3856-3873, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32141738

RESUMEN

For better exciton separation and high catalytic activity, the most trailblazing stratagem is to construct defect engineered low-dimensional p-n heterojunction framed photocatalytic systems. In this context, we have developed a rod-sheet (1D-2D) p-n heterojunction of MCeO2-BiFeO3 by a simple hydrothermal method and scrutinized its photocatalytic performance toward N2 fixation and phenol/Cr(VI) detoxification. The intimate contact between MCeO2 and BiFeO3 in the junction material is well established via X-ray diffraction (XRD), UV-vis diffuse reflectance spectrosopy (DRS), transmission electron microscopy (TEM), and photoelectrochemical studies. Further, scanning electron microscopy (SEM) and TEM pictures clearly support the decoration of MCeO2 nanorods over BiFeO3 sheets and also depict the junction boundary. Additionally, photoluminescence (PL), electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), and Raman measurements give solid evidence toward the presence of an oxygen vacancy. Moreover, the Mott-Schottky result indicates a feasible band edge potential favoring the p-n heterojunction with a built-in electric field between BiFeO3 and MCeO2 favoring a double charge dynamic. The MCeO2-BFO p-n junction displays a notable catalytic activity, i.e., 98.2% Cr(VI) reduction and 85% phenol photo-oxidation, and produces 117.77 µmol h-1 g-1 of ammonia under light irradiation. Electrochemical analysis suggests a four-electron/five proton-coupled N2 photoreduction pathway. The designed oxygen vacancy oriented p-n heterojunction suffering double charge migration shows significant catalytic performance due to effective electron-hole separation as justified via PL, electrochemical impedance spectra (EIS), and Bode phase analysis.

12.
Trop Anim Health Prod ; 52(4): 1759-1767, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31898029

RESUMEN

To find out the effect of reducing energy intake during dry period on milk production, udder health, and body condition, the experiment was conducted on 14 Jersey crossbred cows during whole dry period and continued up to 120 days of lactation. Reduction in energy intake was done during far-off period for each dry cow of treatment group as compared to control group. Statistically analyzed data revealed that overall significantly (P < 0.01) lower DMI and WI were recorded in control than treatment group. Overall significantly (P < 0.01) higher total milk production was found in treatment than control group. Overall significantly (P < 0.01) lower milk SCC, MCMT, pH, and EC were found in treatment than control group. Nonsignificant difference in milk fat, SNF, total solid, total protein, and fat:protein ratio was found. Overall significantly (P < 0.01) better quality milk (MBRT) was found in treatment than control groups. BCS during dry period and at calving was significantly (P < 0.01) different between groups. Significantly (P < 0.01) higher plasma NEFA concentration was estimated in control than treatment groups in all stages. No significant difference was found for plasma concentrations of glucose, urea, and total protein. The coefficients of correlation indicated significant (P < 0.01) correlation among BCS, milk production, milk SCC, MCMT, pH, and EC. It can be concluded that reducing energy intake during far-off dry period can lead to achieve optimum BCS at calving. Suitable BCS at calving was beneficial to get higher milk production with improved quality, better maintenance of udder health and body condition of Jersey crossbred cows at tropical lower Gangetic region.


Asunto(s)
Bovinos/fisiología , Dieta/veterinaria , Metabolismo Energético/fisiología , Glándulas Mamarias Animales/fisiología , Leche/fisiología , Alimentación Animal/análisis , Animales , Bovinos/genética , Ingestión de Energía , Femenino , Lactancia
13.
Indian J Endocrinol Metab ; 23(4): 500-501, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31741915
14.
Vet World ; 12(5): 621-628, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31327896

RESUMEN

AIM: This study aimed to study the electrophoretic properties of seminal plasma and sperm proteins of Black Bengal buck semen and their correlation with in vitro sperm characters and freezability. MATERIALS AND METHODS: Semen ejaculates from nine Black Bengal bucks were collected by artificial vagina (n=20/buck). Ejaculates were evaluated for in vitro sperm characters and electrophoretic profile of seminal protein. In vitro sperm characters were evaluated immediately after collection, after completion of equilibration period, and after freeze-thawing. For seminal protein studies, seminal plasma proteins were precipitated by ice-cold ethanol method, and sperm proteins were extracted by Triton X detergent extraction method. Discontinuous sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was performed to assess the molecular weight of seminal proteins. Correlation between in vitro sperm characters and protein bands was determined by Pearson's correlation coefficient, and two-way ANOVA was applied to find the individual buck differences. RESULTS: Significant difference (p<0.01) among the bucks was noticed in the in vitro sperm characters evaluated at all the three stages of semen evaluation such as immediately after collection, after completion of equilibration period, and post-freeze thawing. Progressive loss of sperm motility, membrane integrity, and other in vitro sperm characters were noticed during cryopreservation. A total of ten protein bands in the molecular weight ranging from 17 to 180 kDa were found in the SDS-PAGE of seminal plasma proteins, while nine bands of 17-134 kDa were observed in sperm proteins. Seminal plasma proteins of molecular weight 75, 62-49, 20, and 17 kDa and sperm proteins of 75, 20, and 17 kDa were present in all the nine bucks (100%) screened, and variation among the bucks was noticed for the presence of other proteins. Seminal plasma protein of 180-134 kDa showed a negative correlation with individual motility (-0.716) and functional membrane integrity of sperm cells (-0.724) in post-freeze-thaw analysis and 48 kDa protein had a positive correlation with individual motility (0.649) and functional membrane integrity of sperm cells (0.664) in post-thaw analysis. Sperm proteins of 63 kDa had a negative correlation (-0.616) with sperm concentration in neat semen. CONCLUSION: Variation among the bucks was noticed in the in vitro sperm characters and semen freezability. Correlation between seminal proteins and in vitro sperm characters and semen freezability had been found which might be useful as a tool to select breeding bucks.

15.
Acta Virol ; 63(1): 3-18, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30879308

RESUMEN

Bluetongue (BT) is an economically important, infectious and non-contagious disease of ruminant animals. BT disease is caused by bluetongue virus (BTV) of the genus Orbivirus (the family Reoviridae). BTV is transmitted by certain species of biting midges of the genus Culicoides. Although originally BT was restricted to African continent, now it is present in all the continents except Antarctica. Conventional BT vaccines such as live attenuated and inactivated vaccines showed different degree of success in BT control. However, conventional vaccines have certain disadvantages of reversion to virulent strain and frequent booster dose requirement. Several BT outbreaks in India and the rest of the world open a new insight for development of better vaccines. The development in molecular biology techniques allowed the development and validation of several modern vaccines such as subunit vaccine, recombinant vector vaccine, disabled infections single cycle (DISC) vaccine, differentiating infected from vaccinated animals (DIVA) approach etc. Most of these vaccines are considered as safer, having better protective immune response and provided cross-protective immunization against more than one serotype. Keywords: bluetongue virus; live vaccine; inactivated vaccine; DISC; recombinant vaccine.


Asunto(s)
Virus de la Lengua Azul , Lengua Azul , Vacunas Virales , Animales , Lengua Azul/prevención & control , Lengua Azul/virología , Rumiantes/virología , Ovinos , Vacunas Atenuadas , Vacunas Sintéticas
16.
Mol Biol Rep ; 46(2): 1809-1817, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30694457

RESUMEN

Mulberry (Morus alba L.) is the sole food source for the mulberry silkworm, Bombyx mori and therefore important for sericulture industry. Different abiotic stress conditions like drought, salt, heat and cold stress adversely affect the productivity and quality of mulberry leaves. Quantitative real time PCR (qPCR) is a reliable and widely used method to identify abiotic stress responsive genes and molecular mechanism in different plant species. Selection of suitable reference genes is important requirement for normalizing the expression of genes through qRT-PCR study. In the present study, we have selected eight candidate reference genes in mulberry for analyzing their expression stability in different abiotic stress treatments including drought, salt, heat and cold stresses. The expression stability of these reference genes was determined using geNorm, NormFinder and RefFinder statistical algorithms. The results showed that Ubiquitin and protein phosphatase 2A regulatory subunit A (PP2A) were the most stable genes across all the treatment samples. However, analysis of individual stresses revealed different expression profiles and stability of reference genes. Actin3 and PP2A were most stable in drought and salt conditions respectively. RPL3 most preferred in heat stress and Ubiquitin was most stable in cold stress. We propose the ubiquitin and PP2A are the preferred reference genes for normalization of gene expression data from abiotic stresses. In addition, Actin3 are preferred for drought stress, PP2A for salt stress, RPL3 for heat stress and Ubiquitin for cold stress studies.


Asunto(s)
Expresión Génica/genética , Morus/genética , Estrés Fisiológico/genética , Sequías , Perfilación de la Expresión Génica/métodos , Perfilación de la Expresión Génica/normas , Regulación de la Expresión Génica de las Plantas/genética , Genes de Plantas/genética , Respuesta al Choque Térmico , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Estándares de Referencia
17.
Am J Physiol Endocrinol Metab ; 316(1): E16-E33, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30153063

RESUMEN

Polycystic ovary syndrome (PCOS) is highly associated with cardiometabolic risk and the metabolic syndrome (MetS), predisposing women to increased risk of developing type 2 diabetes and cardiovascular disease. Metformin is commonly used to treat insulin resistance-glucose intolerance, and flutamide, an androgen receptor (AR) antagonist, is used to target hyperandrogenemia and dyslipidemia. Currently, the physiological mechanism of action of these treatments on androgen, lipidogenic, and insulin signaling pathways remains unclear in PCOS. The aim of this study was to investigate the effects and mechanisms of action of metformin and flutamide on plasma lipid-apolipoprotein (Apo)B-lipoprotein and insulin-glucose metabolism, and endocrine-reproductive indices in a PCOS-prone MetS rodent model. PCOS-prone rodents were treated with metformin (300 mg/kg body wt), flutamide (30 mg/kg body wt), or metformin + flutamide combination treatment for 6 wk. Metformin was shown to improve fasting insulin and HOMA-IR, whereas flutamide and combination treatment were shown to reduce plasma triglycerides, ApoB48, and ApoB100, and this was associated with decreased intestinal secretion of ApoB48/triglyceride. Flutamide and metformin were shown to reduce plasma androgen indices and to improve ovarian primary and preovulatory follicle frequency. Metformin treatment increased hepatic estrogen receptor (ER)α, and metformin-flutamide decreased intestinal AR and increased ERα mRNA expression. Metformin-flutamide treatment upregulated hepatic and intestinal insulin signaling, including insulin receptor, MAPK1, and AKT2. In conclusion, cardiometabolic risk factors, in particular ApoB-hypertriglyceridemia, are independently modulated via the AR, and understanding the contribution of AR and insulin-signaling pathways further may facilitate the development of targeted interventions in high-risk women with PCOS and MetS.


Asunto(s)
Antagonistas de Andrógenos/farmacología , Glucemia/efectos de los fármacos , Receptor alfa de Estrógeno/efectos de los fármacos , Flutamida/farmacología , Hipoglucemiantes/farmacología , Insulina/metabolismo , Síndrome Metabólico/metabolismo , Metformina/farmacología , Animales , Apolipoproteína B-100/efectos de los fármacos , Apolipoproteína B-100/metabolismo , Apolipoproteína B-48/efectos de los fármacos , Apolipoproteína B-48/metabolismo , Apolipoproteínas B/efectos de los fármacos , Apolipoproteínas B/metabolismo , Glucemia/metabolismo , Enfermedades Cardiovasculares , Modelos Animales de Enfermedad , Receptor alfa de Estrógeno/genética , Femenino , Fase Folicular , Resistencia a la Insulina , Mucosa Intestinal/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/efectos de los fármacos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Folículo Ovárico/efectos de los fármacos , Ovario/efectos de los fármacos , Síndrome del Ovario Poliquístico/metabolismo , Proteínas Proto-Oncogénicas c-akt/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero , Ratas , Receptor de Insulina/efectos de los fármacos , Receptor de Insulina/metabolismo , Riesgo , Triglicéridos/metabolismo
18.
Indian J Cancer ; 54(1): 362-367, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29199724

RESUMEN

INTRODUCTION: Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor in adults. The standard management has been maximum surgical resection followed by adjuvant radiotherapy with concurrent chemotherapy followed by adjuvant chemotherapy. Although the survival rate of patients with GBM has improved with recent advancements in treatment, the prognosis remains generally poor. The median survival rates are in the range of 9-12 months and 2-year survival rates are in the range of 8%-12%. MATERIALS AND METHODS: A single-institution retrospective review of 61 patients of GBM from 2012 to 2014. Data regarding patient factors, disease factors, and treatment factors were collected and survival has been calculated. RESULTS: A total of 61 patients with GBM were analyzed. GBM is commonly seen in sixth decade of life. Male to female ratio is 2.6:1. The right side of the brain is commonly involved with right frontal lobe being the most common site. The median follow-up was 4.6 months. The median survival of our patients was 8 months. The 1-year and 2-year survival rates were 20% and 3.27%, respectively. CONCLUSIONS: The overall survival and prognosis in patients with GBM remains poor despite of constant research and studies. Concurrent chemoradiotherapy followed by adjuvant chemotherapy with temozolomide should be used after maximal resection to improve the survival.


Asunto(s)
Glioblastoma/epidemiología , Glioblastoma/radioterapia , Pronóstico , Adulto , Anciano , Quimioradioterapia , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Glioblastoma/tratamiento farmacológico , Glioblastoma/cirugía , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Radioterapia Adyuvante , Estudios Retrospectivos , Temozolomida , Adulto Joven
19.
ACS Appl Mater Interfaces ; 9(42): 37310-37320, 2017 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-28990750

RESUMEN

Organic-inorganic nanocomposite self-standing films of Gd3Ga3Al2O12 (GGAG) uniformly dispersed in poly(methyl methacrylate) (PMMA) and polystyrene polymer are prepared for radiography application. GGAG:Ce nanoscintillator has been chosen because of its high light output and fast decay time. The nanopowder of GGAG is synthesized by coprecipitation method and dispersed in the polymer matrix by a simple blending technique. The nanocomposite films of thickness in the range of 150-450 µm with a very high inorganic content is achieved by this technique. These films are characterized by their uniformity, optical absorption, photoluminescence, and radioluminescence. These films are further tested for their application in radiography by recording X-ray images using a commercially available charge-coupled device camera. A resolution of 10 lp/mm is obtained using GGAG:PMMA composite film with 50% loading, confirming their application in imaging devices.

20.
Appl Radiat Isot ; 128: 210-215, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28735114

RESUMEN

Determination of impurities namely Ca, Mn, Fe, Ni, Zn, Sr and Pb in graphite by energy dispersive X-ray fluorescence spectrometry is described using microfocused synchrotron radiation. The internal standard and standard addition methodologies were adopted for quantification and the results were compared with tube-based X-ray fluorescence spectrometry. Analysis of the results by the F and t-tests revealed their statistical equivalence. Synchrotron measurements improved the detection limits by an order of magnitude compared to the tube based technique. Cr and Zr, which were below the quantification limit in tube based technique, were also quantified by synchrotron based technique.

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