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ObjectiveTo assess the accuracy of sweat conductivity among newborns and very young infants.DesignProspective, population-based, diagnostic test accuracy study.SettingPublic Statewide Newborn Screening Programme where the incidence rate of cystic fibrosis (CF) is ≈1:11 000.PatientsNewborns and very young infants with positive two-tiered immunoreactive trypsinogen.InterventionsSweat conductivity and sweat chloride were performed simultaneously, on the same day and facility by independent technicians, with the cut-off values of 80 mmol/L and 60 mmol/L, respectively.Main outcome measuresSensitivity, specificity, positive and negative predictive values (PPV and NPV), overall accuracy, positive and negative likelihood ratios (+LR, -LR) and post (sweat conductivity (SC)) test probability were calculated to assess SC performance.Results1193 participants were included, 68 with and 1108 without CF, and 17 with intermediate values. The mean (SD) age was 48 (19.2) days, ranging from 15 to 90 days. SC yielded sensitivity of 98.5% (95% CI 95.7 to 100), specificity of 99.9% (95% CI 99.7 to 100), PPV of 98.5% (95% CI 95.7 to 100) and NPV of 99.9% (95% CI 99.7 to 100), overall accuracy of 99.8% (95% CI 99.6 to 100), +LR of 1091.7 (95% CI 153.8 to 7744.9) and -LR of 0.01 (95% CI 0.00 to 0.10). After a positive and negative sweat conductivity result, the patient’s probability of CF increases around 350 times and drops to virtually zero, respectively.ConclusionSweat conductivity had excellent accuracy in ruling in or ruling out CF after positive two-tiered immunoreactive trypsinogen among newborns and very young infants.

The planning of planting/harvest operations improves yield and economic returns of sugarcane production systems. This study aims to define homogenous regions and optimum planting dates for sugarcane using simulated water-limited yield in the state of Goiás, Brazil. Yw was simulated using crop model and 24 planting dates across the year, including gridded weather data and soil water availability to the crop over the state in a grid cell size of 0.5 × 0.5°. The crop model was evaluated comparing simulated and measured yield tendency across planting dates. Homogeneous regions were obtained based on Yw, using the Ward’s method and Euclidean distance. The crop model was able to replicate yield tendency across planting dates. The clustering divided the state into four homogenous regions, where optimum planting period had different intervals due to the interaction with climate and soil. The optimum planting window had four dates for the region with lower Yw (105 t ha−1). The region with higher Yw (131 t ha−1) had the longer optimum window, with seven dates, but with the higher yield reduction (− 6%) than other regions (− 3%) when planting date was changed from 1st to 2nd better dates. This way, the results and the approach used in this study defines yield level and optimal planting dates, which can be apply to define harvest period and the area required to supply the sugarcane mill demands, leading to better machinery and labor work management, helping to elaborate mills and state-level strategies to increase sugarcane production.

Sugarcane (Saccharum officinarumL.) yield is affected by climate, soil and management. The main approach used in Brazil defines the suitable area for growth considering soil and climate data, without considering the capacity of local management in reducing yield-limiting factors. Thus, the aim of this study is to characterize homogenous areas using sugarcane actual yield, climate, total plant-available soil water capacity (TASW), and production intensity data. The study was conducted in the Goiás state, totalizing 246 counties. The first step was to group areas based on actual yield obtained from 1973 to 2016. The groups were characterized considering climate (rainfall and air temperature), soil (TASW), and sugarcane production data. Actual sugarcane yield formed eight homogenous groups, numbered 1–8, containing 12 and 50 counties each group. The counties groups with a higher yield have a higher production intensity. They are near mills, have a higher TASW, and are divided in traditional and recent expansion areas. The counties groups with a lower yield have a lower TASW and a higher air temperature. Hotter regions are in the western and northern state border. New areas of expansion were available near current sugarcane mills within areas with a higher TASW. Thus, preferential regions were defined by associating edaphoclimatic conditions with high yield. These areas can receive support to improve sugarcane production.

Among modern refractory concretes (MRC), those with low cement content (LCC) where CAC = 4-6wt%, are widely commercialized, considering that their properties approximate those of burned bricks of the same class. In this work, the effect of the modulus q of Andreasen ́s particle size distribution, on the physical (porosity, bulk density) and mechanical (flexural strength and dynamic elastic modulus) properties, of either pre-fired or simply dried specimens of a ≥85% Al2O3 LCC ́s, was investigated. The different LCC ́s samples were formulated according to the Andreasen ́s model, using several distribution modulus (q = 0.22, 0.26, 0.30, 0.33 and 0.42). Measurements of the Dynamic Elastic Modulus (DEM) as a function of temperature (25 to 1500°C), using the Impulse Excitation Technique (IET), were taken as a key indicator of the microstructure dynamic behavior. For the sake of just a punctual comparative term, the physical and mechanical properties of a conventional type refractory concrete (CRC) with a higher CAC percentage (15%) formulated with q = 0.26 was also evaluated. The results indicated that distribution modulus values of; q =0.22, 0,26, 0.30 and 0.33 lead to higher DEM values. While q=0.42 lead to the smallest value in the LCC series. Also, higher DEM values ​​were obtained for LCC ́s (CAC = 5%) than for conventional concrete with CAC = 15% under the same value of q for pre-fired samples. In addition, by observing the occurrence of damping effects in specific temperature ranges, the loss of crystallization water from the calcium aluminate hydrates, as well as the development of pyroplastic behavior could be inferred. The gathered information is relevant to predict the behavior of LCC ́s and CRC ́s when put into service for the first time.