Search results for "ample"
showing 10 items of 2398 documents
Oxygen isotope and salinity measurements of coastal surface waters in the Gulf of Maine
2020
These data include salinity and oxygen isotope measurements of water samples collected from coastal sites along the Gulf of Maine between 2003 and 2015. In particular, a suite of samples were collected along the coast of Maine, east of Penobscot Bay, on a monthly basis between April 2014 and March 2015. These data also include several freshwater samples collected from the Kennebec and Penobscot Rivers on a semi-monthly basis in 2014 and 2015. For the water samples with sample IDs starting with DSW, JSW, NSW, or OSW: The water samples were collected by hand from shore or boat using French square glass bottles with phenolic polycone lined caps. Salinity was measured using a Oakton SALT 6+ han…
On-line in-tube solid phase microextraction coupled to capillary liquid chromatography-diode array detection for the analysis of caffeine and its met…
2019
Abstract In-tube solid phase microextraction (IT-SPME) coupled on-line to capillary liquid chromatography with diode array detection provides a simple and fast analytical methodology for the simultaneous quantitation of caffeine and its three primary metabolites (theobromine, paraxanthine and theophylline) in micro samples of serum, saliva and urine matrices. The sample amount required for one analysis was only 2.5 μL of saliva, 6.25 μL of serum or 40 μL of urine, a requirement for its implementation in a hospital laboratory for preterm newborns, where sample availability is a major problem. In standard conditions, 25 μL of diluted saliva or serum (or 100 μL of urine) were processed by IT-S…
Salivary levels of Tumour Necrosis Factor-alpha in patients with recurrent aphthous stomatitis
2010
Objetives: Recurrent aphthous stomatitis (RAS) is a common pathology of the oral mucosa with a complex and multifactorial etiology. Tumour Necrosis Factor-alpha (TNF?) is a cytokine with an important but not well-known role in the development of new lesions in RAS patients. Modifications of salivary levels of TNF? in RAS patients during the active periods of the disease have been measured in this work. The possible implication of TNF? in RAS etiology is also discussed. Study design: The study group was composed of 20 patients previously diagnosed with RAS and randomly selected. As a control group 10 healthy patients were also randomly selected. In both groups a TNF? assessment was carried o…
Estimation of Pyruvic acid in serum and saliva among healthy and potentially malignant disorder subjects – a stepping stone for cancer screening?
2014
Background: According to Warburg’s effect, the rate of glycolysis increases in cancerous cells. This will increase overall levels of pyruvic acid. The present on-going study was conducted to estimate the levels of pyruvic acid in saliva and serum in normal, oral PMD subjects. Material and Methods: A total of 50 subjects in healthy, PMD of the oral cavity individuals were selected based on clinical and histological criteria. Collected saliva and serum samples were subjected to pyruvic acid level estimation using biochemical analysis. Results: Of the 50 participants 25 (13: Males; 12: Females) & 25 (16: Males; 9: Females) were PMD group. Independent samples t test showed statistically signifi…
Assessment of microbial quality of commercial and home-made tiger-nut beverages
2012
Aims: We aimed to assess the microbiological quality of Spanish commercial tiger-nut beverages as well as home-made samples collected from supermarkets, street vendors, juice bars and ice-cream parlours located in Valencia. Methods and Results: Microbiological analysis of 44 tiger-nut beverages samples were carried out according to International Standard Organization (ISO) norms and published works which included the total viable count, Enterobacteriaceae, Escherichia coli, Staphylococcus aureus, Salmonella, Bacillus cereus, yeasts, moulds, Yersinia enterocolitca, Clostridium perfringens, Vibrio spp. and Listeria monocytogenes. The obtained results indicated that all the commercial sample…
Estimating the chance of success of archaeometric analyses of bone: UV-induced bone fluorescence compared to histological screening
2011
Abstract For most archaeometric analyses on archaeological bone material, such as the determination of the isotopic composition or genetic approaches, an advanced degree of diagenetic alteration can make designated analysis impossible. Since the lack of a positive signal is mostly seen only after time consuming and cost intensive sample processing, the need for an easy-to-apply screening method that allows a pre-selection of samples containing well-preserved biomolecules is obvious. In this study, we visually determined the UV-induced autofluorescence of 76 horse bone cross-sections, all from prehistoric archaeological sites of varying environmental and chronological background. In order to…
Ítems contextualizados de PISA Ciencias: La conexión entre las demandas cognitivas y las características de contexto de los ítems
2016
El uso frecuente de contextos en los ítems de la prueba se basa en la premisa de que la contextualización de ítems es una estrategia eficaz para comprobar si los estudiantes pueden aplicar o transferir sus conocimientos. En este trabajo, seguimos una línea de investigación que se centra en probar esta premisa. Se presenta un estudio de las características del contexto en una muestra de ítems de PISA ciencias de 2006 y 2009 y cómo estas características, así como el rendimiento del estudiante puede estar relacionado con las demandas cognitivas en los ítems. El estudio se basa en dos preguntas de investigación: (1) ¿Cuáles son las demandas cognitivas de los ítems contextualizados en la muestra…
Assisted Self-Adapted Testing: A Comparative Study
2004
Abstract: A new type of self-adapted test (S-AT), called Assisted Self-Adapted Test (AS-AT), is presented. It differs from an ordinary S-AT in that prior to selecting the difficulty category, the computer advises examinees on their best difficulty category choice, based on their previous performance. Three tests (computerized adaptive test, AS-AT, and S-AT) were compared regarding both their psychometric (precision and efficiency) and psychological (anxiety) characteristics. Tests were applied in an actual assessment situation, in which test scores determined 20% of term grades. A sample of 173 high school students participated. Neither differences in posttest anxiety nor ability were obta…
An interlaboratory study as useful tool for proficiency testing of chemical oxygen demand measurements using solid substrates and liquid samples with…
2009
In 2008, the first Proficiency Testing Scheme of Chemical Oxygen Demand (1stCOD-PTADG) was conducted to assess the results obtained for different research groups whose field work is mainly anaerobic digestion. This study was performed using four samples, two solid samples as raw materials and two solid samples to prepare high concentration suspended solid solutions. Invitations were sent to a large number of laboratories, mainly to anaerobic digestion research groups. Finally, thirty labs from sixteen countries agreed to participate, but for different reasons four participants could not send any data. In total, twenty-six results were reported to the COD-PT coordinator. This study showed th…
Job satisfaction and depression in the Spanish Society of Periodontology and Research (SEPA) members, and their relation to the burnout syndrome. Cre…
2012
Objective: This study is aimed at getting to know the existing relationship between the dimensions of the burnout syndrome and job satisfaction, on one hand, and depressive feelings on the other through the creation of a structural model aimed at relating all these concepts on a sample of Spanish periodontists. Study design: The initial sample comprised 284 individuals, who represented 20% of the members of the Spanish Society of Periodontology and Research (www.SEPA.es). These individuals were chosen randomly by means of stratified sampling with proportional affixation by their autonomous community of residence. All participants were sent by post the MBI, CET and job-satisfaction questionn…