Symphysis-fundal height curve in the diagnosis of fetal growth deviations

OBJECTIVE: To validate a new symphysis-fundal curve for screening fetal growth deviations and to compare its performance with the standard curve adopted by the Brazilian Ministry of Health. METHODS: Observational study including a total of 753 low-risk pregnant women with gestational age above 27 weeks between March to October 2006 in the city of João Pessoa, Northeastern Brazil. Symphisys-fundal was measured using a standard technique recommended by the Brazilian Ministry of Health. Estimated fetal weight assessed through ultrasound using the Brazilian fetal weight chart for gestational age was the gold standard. A subsample of 122 women with neonatal weight measurements was taken up to seven days after estimated fetal weight measurements and symphisys-fundal classification was compared with Lubchenco growth reference curve as gold standard. Sensitivity, specificity, positive and negative predictive values were calculated. The McNemar χ2 test was used for comparing sensitivity of both symphisys-fundal curves studied. RESULTS: The sensitivity of the new curve for detecting small for gestational age fetuses was 51.6% while that of the Brazilian Ministry of Health reference curve was significantly lower (12.5%). In the subsample using neonatal weight as gold standard, the sensitivity of the new reference curve was 85.7% while that of the Brazilian Ministry of Health was 42.9% for detecting small for gestational age. CONCLUSIONS: The diagnostic performance of the new curve for detecting small for gestational age fetuses was significantly higher than that of the Brazilian Ministry of Health reference curve.

Filter Paper Method for the Determination of the Soil Water Retention Curve

ABSTRACT High cost and long time required to determine a retention curve by the conventional methods of the Richards Chamber and Haines Funnel limit its use; therefore, alternative methods to facilitate this routine are needed. The filter paper method to determine the soil water retention curve was evaluated and compared to the conventional method. Undisturbed samples were collected from five different soils. Using a Haines Funnel and Richards Chamber, moisture content was obtained for tensions of 2; 4; 6; 8; 10; 33; 100; 300; 700; and 1,500 kPa. In the filter paper test, the soil matric potential was obtained from the filter-paper calibration equation, and the moisture subsequently determined based on the gravimetric difference. The van Genuchten model was fitted to the observed data of soil matric potential versus moisture. Moisture values of the conventional and the filter paper methods, estimated by the van Genuchten model, were compared. The filter paper method, with R2 of 0.99, can be used to determine water retention curves of agricultural soils as an alternative to the conventional method.

Soil Compaction Curve of an Oxisol Under Sugarcane Planted After In-row Deep Tillage

ABSTRACT Soil tillage that maintains the productivity of sugarcane plantations, providing an area for the root development and without traffic on crop rows, has given rise to new technologies in rural areas. The purpose of this study was to evaluate the soil physical properties in two sugarcane plantations, one of which was prepared with deep tilling and the other with conventional tillage. The experiment was conducted in Lençóis Paulista, São Paulo State. Soil penetration resistance and relative density were analyzed. The cone index was lower in deep-tilled soil without traffic in all layers, than in deep-tilled soil with traffic and in conventional tillage. In both tillage treatments, the relative density values were acceptable in the 0.00-0.15 m soil layer, but considered detrimental for sugarcane development in the 0.15-0.30 and 0.30-0.45 m layers.

Receiver operating characteristic (ROC) curve for classification of18F-NaF uptake on PET/CT

Abstract Objective: To assess the cutoff values established by ROC curves to classify18F-NaF uptake as normal or malignant. Materials and Methods: PET/CT images were acquired 1 hour after administration of 185 MBq of18F-NaF. Volumes of interest (VOIs) were drawn on three regions of the skeleton as follows: proximal right humerus diaphysis (HD), proximal right femoral diaphysis (FD) and first vertebral body (VB1), in a total of 254 patients, totalling 762 VOIs. The uptake in the VOIs was classified as normal or malignant on the basis of the radiopharmaceutical distribution pattern and of the CT images. A total of 675 volumes were classified as normal and 52 were classified as malignant. Thirty-five VOIs classified as indeterminate or nonmalignant lesions were excluded from analysis. The standardized uptake value (SUV) measured on the VOIs were plotted on an ROC curve for each one of the three regions. The area under the ROC (AUC) as well as the best cutoff SUVs to classify the VOIs were calculated. The best cutoff values were established as the ones with higher result of the sum of sensitivity and specificity. Results: The AUCs were 0.933, 0.889 and 0.975 for UD, FD and VB1, respectively. The best SUV cutoffs were 9.0 (sensitivity: 73%; specificity: 99%), 8.4 (sensitivity: 79%; specificity: 94%) and 21.0 (sensitivity: 93%; specificity: 95%) for UD, FD and VB1, respectively. Conclusion: The best cutoff value varies according to bone region of analysis and it is not possible to establish one value for the whole body.

Turbidimetry as an alternative method to determine the rating curve of suspended sediments

Understanding hydrosedimental behavior of a watershed is essential for properly managing and using its hydric resources. The objective of this study was to verify the feasibility of the alternative procedure for the indirect determination of the sediment key curve using a turbidimeter. The research was carried out on the São Francisco Falso River, which is situated in the west of the state of Paraná on the left bank of ITAIPU reservoir. The direct method was applied using a DH-48 sediment suspended sampler. The indirect method consisted of the use of a linigraph and a turbidimeter. Based on the results obtained, it was concluded that the indirect method using a turbidimeter showed to be fully feasible, since it gave a power function-type mathematical model equal of the direct method. Furthermore, the average suspended sediment discharge into the São Francisco Falso River during the 2006/2007 harvest was calculated at 7.26 metric t day-1.

Dose-response curve to soil applied herbicides and susceptibility evaluation of different amaranthus species using model identity

Greenhouse studies were conducted in 2008-2009 with the objective of adjusting dose-response curves of the main soil-applied herbicides currently used in cotton for the control of Amaranthus viridis, A. hybridus, A. spinosus, A. lividus, as well as comparing susceptibility among different species, using the identity test models. Thirty six individual experiments were simultaneously carried out in greenhouse, in a sandy clay loam soil (21% clay, 2.36% OM) combining increasing doses of the herbicides alachlor, clomazone, diuron, oxyfluorfen, pendimethalin, prometryn, S-metolachlor, and trifluralin applied to each species. Dose-response curves were adjusted for visual weed control at 28 days after herbicide application and doses required for 80% (C80) and 95% (C95) control were calculated. All herbicides, except clomazone and trifluralin, provided efficient control of most Amaranthus species, but substantial differences in susceptibility to herbicides were found. In general, A. lividus was the least sensitive species, whereas A. spinosus demonstrated the highest sensitivity to herbicides. Alachlor, diuron, oxyfluorfen, pendimethalin, S-metolachlor, and prometryn are efficient alternatives to control Amaranthus spp. in a range of doses that are currently lower than those recommended to cotton.

Inspiratory flow-volume curve in snoring patients with and without obstructive sleep apnea

We analyzed the flow-volume curves of 50 patients with complaints of snoring and daytime sleepiness in treatment at the Pneumology Unit of the University Hospital of Brasília. The total group was divided into snorers without obstructive sleep apnea (OSA) (N = 19) and snorers with OSA (N = 31); the patients with OSA were subdivided into two groups according to the apnea/hypopnea index (AHI): AHI<20/h (N = 14) and AHI>20/h (N = 17). The control group (N = 10) consisted of nonsmoking subjects without complaints of snoring, daytime sleepiness or pulmonary diseases. The population studied (control and patients) consisted of males of similar age, height and body mass index (BMI); spirometric data were also similar in the four groups. There was no significative difference in the ratio of forced expiratory and inspiratory flows (FEF50%/FIF50%) in any group: control, 0.89; snorers, 1.11; snorers with OSA (AHI<20/h), 1.42, and snorers with OSA (AHI>20/h), 1.64. The FIF at 50% of vital capacity (FIF50%) of snoring patients with or without OSA was lower than the FIF50% of the control group (P<0.05): snorers 4.30 l/s; snorers with OSA (AHI<20/h) 3.69 l/s; snorers with OSA (AHI>20/h) 3.17 l/s and control group 5.48 l/s. The FIF50% of patients with severe OSA (AHI>20/h) was lower than the FIF50% of snorers without OSA (P<0.05): 3.17 l/s and 4.30 l/s, respectively. We conclude that 1) the FEF50%/FIF50% ratio is not useful for predicting OSA, and 2) FIF50% is decreased in snoring patients with and without OSA, suggesting that these patients have increased upper airway resistance (UAR).

Standard-curve competitive RT-PCR quantification of myogenic regulatory factors in chicken embryos

The reverse transcription-polymerase chain reaction (RT-PCR) is the most sensitive method used to evaluate gene expression. Although many advances have been made since quantitative RT-PCR was first described, few reports deal with the mathematical bases of this technique. The aim of the present study was to develop and standardize a competitive PCR method using standard-curves to quantify transcripts of the myogenic regulatory factors MyoD, Myf-5, Myogenin and MRF4 in chicken embryos. Competitor cDNA molecules were constructed for each gene under study using deletion primers, which were designed to maintain the anchorage sites for the primers used to amplify target cDNAs. Standard-curves were prepared by co-amplification of different amounts of target cDNA with a constant amount of competitor. The content of specific mRNAs in embryo cDNAs was determined after PCR with a known amount of competitor and comparison to standard-curves. Transcripts of the housekeeping ß-actin gene were measured to normalize the results. As predicted by the model, most of the standard-curves showed a slope close to 1, while intercepts varied depending on the relative efficiency of competitor amplification. The sensitivity of the RT-PCR method permitted the detection of as few as 60 MyoD/Myf-5 molecules per reaction but approximately 600 molecules of MRF4/Myogenin mRNAS were necessary to produce a measurable signal. A coefficient of variation of 6 to 19% was estimated for the different genes analyzed (6 to 9 repetitions). The competitive RT-PCR assay described here is sensitive, precise and allows quantification of up to 9 transcripts from a single cDNA sample.

Stability of relative oxygen pulse curve during repeated maximal cardiopulmonary testing in professional soccer players

During cardiopulmonary exercise testing (CPET), stroke volume can be indirectly assessed by O2 pulse profile. However, for a valid interpretation, the stability of this variable over time should be known. The objective was to analyze the stability of the O2 pulse curve relative to body mass in elite athletes. VO2, heart rate (HR), and relative O2 pulse were compared at every 10% of the running time in two maximal CPETs, from 2005 to 2010, of 49 soccer players. Maximal values of VO2 (63.4 ± 0.9 vs 63.5 ± 0.9 mL O2•kg-1•min-1), HR (190 ± 1 vs188 ± 1 bpm) and relative O2 pulse (32.9 ± 0.6 vs 32.6 ± 0.6 mL O2•beat-1•kg-1) were similar for the two CPETs (P > 0.05), while the final treadmill velocity increased from 18.5 ± 0.9 to 18.9 ± 1.0 km/h (P < 0.01). Relative O2 pulse increased linearly and similarly in both evaluations (r² = 0.64 and 0.63) up to 90% of the running time. Between 90 and 100% of the running time, the values were less stable, with up to 50% of the players showing a tendency to a plateau in the relative O2 pulse. In young healthy men in good to excellent aerobic condition, the morphology of the relative O2 pulse curve is consistent up to close to the peak effort for a CPET repeated within a 1-year period. No increase in relative O2pulse at peak effort could represent a physiologic stroke volume limitation in these athletes.

A dose-response curve for biodosimetry from a 6 MV electron linear accelerator

Biological dosimetry (biodosimetry) is based on the investigation of radiation-induced biological effects (biomarkers), mainly dicentric chromosomes, in order to correlate them with radiation dose. To interpret the dicentric score in terms of absorbed dose, a calibration curve is needed. Each curve should be constructed with respect to basic physical parameters, such as the type of ionizing radiation characterized by low or high linear energy transfer (LET) and dose rate. This study was designed to obtain dose calibration curves by scoring of dicentric chromosomes in peripheral blood lymphocytes irradiated in vitro with a 6 MV electron linear accelerator (Mevatron M, Siemens, USA). Two software programs, CABAS (Chromosomal Aberration Calculation Software) and Dose Estimate, were used to generate the curve. The two software programs are discussed; the results obtained were compared with each other and with other published low LET radiation curves. Both software programs resulted in identical linear and quadratic terms for the curve presented here, which was in good agreement with published curves for similar radiation quality and dose rates.

Nitrogen and potassium fertilization on the yield and intensity of the maize white spot

A plant's nutritional balance can influence its resistance to diseases. In order to evaluate the effect of increasing doses of N and K on the yield and severity of the mayze white spot, two experiments were installed in the field, one in the city of Ijaci, Minas Gerais, and the other in the city of Sete Lagoas, Minas Gerais. The experimental delimitation was in randomized blocks with 5 x 5 factorial analysis of variance, and four repetitions. The treatments consisted of five doses of N (20; 40; 80; 150; 190 Kg ha-1of N in the experiments 1 and 2) and five doses of K (15; 30; 60; 120; 180 Kg ha-1of K in experiment 1 and 8.75; 17.5; 35; 50; 100 Kg ha-1of K in experiment 2). The susceptible cultivar 30P70 was planted in both experiments. The plot consisted of four rows 5 meters long, with a useful area consisting of two central rows 3 meters each. Evaluations began 43 days after emergence (DAE) in the first experiment and 56 DAE in the second one. There was no significant interaction between doses of N and K and the disease progress P+. The effect was only observed for N. The K did not influence the yield and the severity of the disease in these experiments. Bigger areas below the severity progress curve of the white spot and better yield were observed with increasing doses of N. Thus, with increasing doses of N, the white spot increased and also did the yield.

A duration e um modelo alternativo: um teste empírico

Estratégias de hedge para portfólios de renda fixa são comumente baseadas na duration. Esse conceito foi desenvolvido tendo como pressuposto que alterações nas taxas de juros serão constantes para toda a estrutura a termo da yield curve, ou seja, que os deslocamentos na yield curve serão paralelos. Este artigo pretende testar esse pressuposto para o mercado futuro de DI1 da BM&F, tendo como base o ano de 1996. Além disso, o artigo compara estratégias de hedge baseadas na duration com estratégias cujo balanceamento é dado por um modelo alternativo que incorpora os efeitos de deslocamentos não-paralelos na yield curve.

Mortality problems in Brazil and in Germany: past-present-future. Learning from each other?

This article was written by a Swiss-German historical demographer after having visited different Brazilian Universities in 1984 as a guest-professor. It aims at promoting a real dialog between developed and developing countries, commencing the discussion with the question: Can we learn from each other? An affirmative answer is given, but not in the superficial manner in which the discussion partners simply want to give each other some "good advice" or in which the one declares his country's own development to be the solely valid standard. Three points are emphasized: 1. Using infant mortality in S. Paulo from 1908 to 1983 as an example, it is shown that Brazil has at its disposal excellent, highly varied research literature that is unjustifiably unknown to us (in Europe) for the most part. Brazil by no means needs our tutoring lessons as regards the causal relationships; rather, we could learn two things from Brazil about this. For one, it becomes clear that our almost exclusively medical-biological view is inappropriate for passing a judgment on the present-day problems in Brazil and that any conclusions so derived are thus only transferable to a limited extent. For another, we need to reinterpret the history of infant mortality in our own countries up to the past few decades in a much more encompassing "Brazilian" sense. 2. A fruitful dialog can only take place if both partners frankly present their problems. For this reason, the article refers with much emprasis to our present problems in dealing with death and dying - problems arising near the end of the demographic and epidemiologic transitions: the superanuation of the population, chronic-incurable illnesses as the main causes of death, the manifold dependencies of more and more elderly and really old people at the end of a long life. Brazil seems to be catching up to us in this and will be confronted with these problems sooner or later. A far-sighted discussion already at this time seems thus to be useful. 3. The article, however, does not want to conclude with the rather depressing state of affairs of problems alternatingly superseding each other. Despite the caution which definitely has a place when prognoses are being made on the basis of extrapolations from historical findings, the foreseeable development especially of the epidemiologic transition in the direction of a rectangular survival curve does nevertheless provide good reason for being rather optimistic towards the future: first in regards to the development in our own countries, but then - assuming that the present similar tendencies of development are stuck to - also in regard to Brazil.

Mortality from asthma in the state of S. Paulo, Brazil (1970-1992)

Mortality from asthma has shown important variations over time in several countries. In Brazil, a mortality study performed in the 60s, covering the cities of S.Paulo and Ribeirão Preto, and other ten cities showed that S.Paulo presented the lowest death rate from asthma among of them all. It was decided to study the time trends of deaths from asthma and from the whole set of respiratory diseases from 1970 to 1992, in the population aged 15-34 yrs. old in the State of S.Paulo, as well as to compare them with those of other countries. Asthma mortality rates during the 23 years of observation since 1975, showed an oscillatory declining pattern with a peak of deaths in the initial years. The linearization of the curve allows the calculation of Pearson's correlation coefficient that was significantly negative, suggesting a decline in the mortality over this period, mainly in the 5-9 yrs. old and 30-34 yrs. old strata. The segmentation of data between the period of ICD-9, 1970 to 1978, and of ICD-9, 1979 and subsequent years, shows that there is stability within each period, in all age-groups, except for that of 5-9 yr. olds between 1970-1978. Comparing the rates of the population aged 15-34 yrs. old for the State of S. Paulo, Brazil, with trends observed in 14 other countries, an intermediate pattern for the first triennial period (1970-1972) as well as for the subsequent triennial periods, emerges. A prevalence study of asthma, a follow up program meant for using emergency rooms and a surveillance of deaths due to all respiratory diseases and specifically to asthma are strongly recommended.

RC-IAL cell line: sensitivity of rubella virus grow

OBJECTIVE: The rapid growth of the rubella virus in RC-IAL² with development of cytopathic effect, in response to rubella virus infection, is described. For purposes of comparison, the rubella virus RA-27/3 strain was titered simultaneously in the RC-IAL, Vero, SIRC and RK13 cell lines. METHODS: Rubella virus RA-27/3 strain are inoculated in the RC-IAL cell line (rabbit Kidney, Institute Adolfo Lutz). Plates containing 1.5x10(5) cells/ml of RC-IAL line were inoculated with 0.1ml s RA-27/3 strain virus containing 1x 10(4)TCID50/0.1ml. A 25% cytopathic effect was observed after 48 hours and 100% after 96 hours. The results obtained were compared to those observed with the SIRC, Vero and RK13 cell lines. Rubella virus was detected by immunohistochemistry. RESULTS: With the results, it was possible to conclude that the RC-IAL cell line is a very good substrate for culturing rubella virus. The cells inoculated with rubella virus were examined by phase contrast microscopy and showed the characteristic rounded, bipolar and multipolar cells. The CPE in RC-IAL was observed in the first 48 hours and the curve of the increased infectivity was practically the same as observed in other cell lines. CONCLUSIONS: These findings are important since this is one the few cell lines described in the literature with a cytopathic effect. So it can be used for antigen preparation and serological testing for the diagnosis of specific rubella antibodies.