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C Monte

Publications and source records attributed to C Monte.

7 recordsLinked to original sources
PubMed2006

The Calibration Kit Spectral Fluorescence Standards--a simple and certified tool for the standardization of the spectral characteristics of fluorescence instruments.

With the Calibration Kit Spectral Fluorescence Standards BAM-F001-BAM-F005, we developed a simple tool for the characterization of the relative spectral responsivity and the long-term stability of the emission channel of fluorescence instruments under routine measurement conditions thereby providing the basis for an improved comparability of fluorescence measurements and eventually standardization. This first set of traceable fluorescence standards, which links fluorescence measurements to the spectral radiance scale in the spectral range of 300-770 nm and has been optimized for spectrofluorometers, can be employed for different measurement geometries and can be adapted to different fluorescence techniques with proper consideration of the underlying measurement principles.

Calibration↗
PubMed2005

Traceability in fluorometry--Part I: Physical standards.

The inter-instrument, inter-laboratory, and long-term comparability of fluorescence data requires the correction of the measured emission and excitation spectra for the wavelength- and polarization-dependent spectral irradiance of the excitation channel at the sample position and the spectral responsivity of the emission channel employing procedures that guarantee traceability to the respective primary standards. In this respect the traceability chain of fluorometry is discussed from a radiometrist's point of view. This involves, in a first step, the realization of the spectral radiance scale, based on the blackbody radiator and electron storage ring, and the spectral responsivity scale, based on the cryogenic radiometer and their control via key comparisons of the national metrology institutes. In a second step, the characterization including state-of-the art uncertainties of the respective source and detector transfer standards such as tungsten strip lamps, integrating sphere radiators, and trap detectors used to disseminate these radiometric quantities to users of spectroscopic techniques is presented.

Journal Article↗
PubMed2005

Traceability in fluorometry: Part II. Spectral fluorescence standards.

The need for the traceable characterization of fluorescence instruments is emphasized from a chemist's point of view, focusing on spectral fluorescence standards for the determination of the wavelength- and polarization-dependent relative spectral responsivity and relative spectral irradiance of fluorescence measuring systems, respectively. In a first step, major sources of error of fluorescence measurements and instrument calibration are revealed to underline the importance of this issue and to illustrate advantages and disadvantages of physical and chemical transfer standards for generation of spectral correction curves. Secondly, examples for sets of traceable chemical emission and excitation standards are shown that cover a broad spectral region and simple procedures for the determination of corrected emission spectra with acceptable uncertainties are presented. With proper consideration of the respective measurement principle and geometry, these dye-based characterization procedures can be not only applied to spectrofluorometers but also to other types of fluorescence measuring systems and even to Raman spectrometers.

Journal Article↗
PubMed2000

[Malnutrition: a secular challenge to child nutrition]

OBJECTIVE: To review current knowledge about child malnutrition, including the historical aspects of the problem, its dimension as a childhood public health problem, its natural history, physiopathology, clinical features, diagnosis and treatment, and strategies used by the health sector to control this disease. METHODS: Information was collected by researching the Medline system, the Bireme library, internet sites of interest, catalogues of publications produced by Brazilian governmental organizations and international institutions dealing with child nutrition. RESULTS: The review pointed out that despite recent world prevalence reduction, child malnutrition is a major public health problem in developing countries. Malnutrition, in any of its forms, contributes for more than 50% of deaths among children under 5 years in those countries. Mortality rates of severely malnourished children treated as in patients have been unchanged for the last five decades. Guidelines for improving the treatment and reducing mortality rates of severely malnourished children treated in hospitals were recently defined by the World Health Organization. Even though some positive results have been achieved by the health sector in reducing child malnutrition prevalence, the effectivity of the interventions is often low. Lack of food might limit the success in treating and preventing malnutrition. Factors that may contribute to the effectiveness of interventions against malnutrition include approaches which reassure the confidence of health professionals about achieving positive results with the proper treatment of malnourished children, establishment of an effective relationship between health professionals and mothers, as well as practical support to mothers in recognizing them as valuable active agents for their children nutrition rehabilitation at the household level. CONCLUSIONS: Throughout the centuries, malnutrition has been the biggest challenge faced by developing countries in order to guarantee to children under five years of age their right of being well nourished and healthy. The current challenge is the proper use of the available scientific knowledge on child nutrition to further reduce the figures for all the types of child malnutrition.

Journal Article↗
PubMed1998

Treatment of malnutrition in Brazil: simple solutions to common problems.

At the largest rehabilitation centre in Ceará, Brazil, the World Health Organization (WHO) guidelines for improved dietary management of severe malnutrition were implemented. Rates of weight gain increased fourfold, daily food costs were reduced, and staff time was saved. Implementation was achieved within 1 week, including training. Other centres are encouraged to adopt similar measures.

Brazil↗
PubMed1996

Airways reactivity, atopy and bronchoalveolar lavage in male smokers with airflow obstruction.

Although cigarette smoking plays a major role in the development of chronic obstructive pulmonary disease, risk factors that might predispose susceptible smokers to develop manifest airflow obstruction are poorly defined. The aim of this study was to investigate whether BAL cell profiles, bronchial hyperresponsiveness, and atopy were different in smokers with and without airway obstruction. Fifty-seven current smokers with (n = 22) and without airflow obstruction (n = 35), defined spirometrically, and 8 nonsmoking subjects (controls) were studied (fiberoptic bronchoscopy and bronchoalveolar lavage (BAL), measurement of IgE concentrations and skin prick testing with common allergen extracts, methacholine bronchoprovocation testing). Mean values of forced expiratory volume in 1 s (FEV1) percent predicted were significantly lower in smokers with obstruction than in those without obstruction (53.1 +/- 16.9 vs. 72.5 +/- 16.6, p < 0.001). Smokers with airflow obstruction showed an improvement in FEV1 < 20% after inhalation of two puffs of 0.250 mg terbutaline. Current smokers as opposed to controls had significantly (p < 0.01) higher values of cells/ml in BAL (78 +/- 72.4 x 10(4) vs. 28.7 +/- 14.5 x 10(4)) and macrophages (90.5 +/- 19.4 vs. 84.3 +/- 9.3%) and lower values of lymphocytes (5.4 +/- 15.4 vs. 13.1 +/- 10.7%). Smokers with obstruction to airflow showed significantly (p < 0.05) higher values of cells/ml in BAL (102 +/- 88 x 10(4)) than smokers without airflow obstruction (63.4 +/- 57.5 x 10(4)) with no differences in differential cell counts. The provocation concentration of methacholine producing a 20% reduction in FEV1 (PC20) was also lower in smokers with obstruction than in smokers without obstruction (2.9 +/- 3.5 vs. 6.4 +/- 7.2 mg/ml, p < 0.05). Differences in atopy were not found. In summary, current smokers with airflow obstruction tended to have more cells recovered by BAL and greater airway responsiveness than smokers without obstruction, although atopy-related parameters were not different for both groups.

Aged↗