Use of hyperspectral imaging for the prediction of moisture content and chromaticity of raw and pretreated apple slices during convection drying

The feasibility of using spectral reflectance information in the visible—near infrared (400–1,000?nm) region to estimate moisture content (g_W/g_DM) and chromaticity (CIELAB) of apple slices was investigated during convection drying. Apple slices were pretreated with hot water blanching (50 and 70°C), acid application (citric and ascorbic), and combinations thereof before drying at 50 and 70°C. Prediction models for the space-averaged spectral reflectance curves were built using the partial least square regression method. A three-component partial least square regression (PLSR) model satisfied the minimal root mean square error (RMSE) criterion for predicting moisture content (avg. RMSEP?=?0.13, r²?=?0.99); importantly, the critical wavelengths remained the same across all pretreatments (540, 817, 977?nm). Similarly, PLSR modeling showed that the optimal set of wavelengths (in terms of RMSE) were invariant across pretreatment for CIELAB a* prediction (543, 966?nm) and CIELAB b* prediction (510, 664, 714, 914, 969?nm). The stability of the information content of these wavelengths across pretreatments indicates their independence of color changes. Additionally, the spatial information in the hyperspectral images was exploited to visualize the performance of the predictive models by pseudo-coloring their values for each pixel in a single apple slice across different drying times. This visualization of spatial distribution of predicted moisture content and chromaticity changes shows significant potential for use in online monitoring of the drying process.     

Can-GLWS: Canadian Great Lakes Weather Service for the Soil and Water Assessment Tool (SWAT) modelling

The rapid rise in availability of large geospatial datasets for the development of hydrological models such as Soil and Water Assessment Tool (SWAT) has led to a dramatic increase in both the demand and availability of web services and tools that assist watershed modellers in incorporating data and knowledge into their modelling frameworks. Within the Canadian Great Lakes region, there is a huge potential for the application of SWAT in integrated water resources management. However, a potential barrier is the preparation of SWAT weather inputs that require time-intensive preprocessing of large data sets. Because such preprocessing is reproducible, the redundancy associated with it can be removed by introducing a web service that enables easy and open dissemination of climate data (including climate change and historical data) in SWAT-ready format. This short communication introduces such a web service called the Canadian Great Lakes Weather Data Service for SWAT (Can-GLWS). It hosts observed (historical) and projected (future) daily precipitation, daily maximum/minimum temperature, as well as weather generator database at regular grids (300 arc seconds or ~10 km) for use in SWAT simulations of the region. The novel Can-GLWS web service offers flexibility in selecting the region of interest by allowing them to be uploaded as a shapefile or to draw a rectangle or a polygon. We believe that such data as a service platform will help many practitioners to explore several issues pertaining to the sustainability of the freshwater resources of Canadian Great Lakes using the SWAT model.     

Total and organic soil carbon in cropping systems of Nepal

The significance of soil organic matter (SOM) in sustaining agriculture has long been recognized. The rate of change depends on climate, cropping system, cropping practice, and soil moisture. A 3-yr on-farm study was conducted in two major agro-ecologies (hills with warm-temperate climate and plains with subtropical climate) of Nepal. The soils in warm-temperate climate are Lithic subgroups of Ustorthents with well-drained loamy texture, and in subtropical climate are Haplaquepts with imperfectly drained loamy texture. Farmers’ predominant cropping systems were selected from different cultivation length in addition to a reference sample collected from adjacent virgin forest. The objectives were to examine the effect of cultivation length and cropping system on total carbon, KMnO₄-oxidizable soil C, C storage, and C/N ratio in two climatic scenarios: warm-temperate and subtropical. A large difference in KMnO₄-oxidizable soil organic C was observed due to the effect of cultivation length and cropping system. However, TC remained similar during the 3-year study. The decrease in KMnO₄-oxidizable C due to cultivation was more in the surface layer (43–56%) than in the subsurface layer (20–30%). Total C in uncultivated, < 10-year cultivated, and > 50-year cultivated soil was 22, 13, and 10 g kg⁻¹ in warm-temperate climate and 10, 6, and 5 g kg⁻¹ in subtropical climate, respectively. During the 3-year study period in both climates, large changes in soil C were observed for KMnO₄-oxidizable C but not for TC, confirming our earlier work on the usefulness of the KMnO₄ oxidized fraction for detecting a relatively short-term increase or decrease in soil C pool. The TC storage in uncultivated, < 10-year cultivated, and > 50-year cultivated soil was 38, 25, and 19 Mg ha⁻¹ in warm-temperate climate and 22, 15, and 12 Mg ha⁻¹ in subtropical climate, respectively. The rice–wheat and maize–potato cropping systems were good in storing soil C of 30 and 20 Mg ha⁻¹ for 0–15-cm soil depth in warm-temperate climate. The rice–wheat cropping system was also good in storing soil C in subtropical climate (19 Mg ha⁻¹) compared with other cropping systems studied.     

Preparation and hydration of β-C2S without stabilizer

The preparation method of β-C ₂S without stabilizer, and their hydration characteristics were studied. β-C₂S is formed when γ-C₂S is heated at about 1000°C or about 1500°C. The hydration kinetics of β-C₂S produced from α′-C₂S is markedly different from that from α-phase. Ca(OH)₂ is hardly produced in the hydration of β-C₂S without stabilizer. Formed C-S-H has a composition of $\text{C/S}\text{? 2}$.     

Dynamics of Population Ageing in Nepal and the Need for Action

Over the past decades, the problem of ageing has grown steadily in Nepal. The demographic measures obtained from different population censuses of Nepal amply demonstrate this. In this context, the present study attempts to analyze population census 2011 data to assess elderly population across the nation by area types, eco-belts, development regions and by gender perspective through computation of major population ageing indicators for these cross-sectional areas of Nepal. The analysis showed that the indicators like median age, proportion of elderly population, elderly dependency ratio and life expectancy at birth have increased significantly in 2011 census compared to 2001 census stressing the need of appropriate actions for the management, welfare and care of elderly people in Nepal. Even though population ageing is found more evident in urban areas regarding median age and index of ageing, percent elderly population aged 60 and above and elderly dependency are actually higher in rural areas which can be attributed to more out-migration of young people in rural areas. Eco-belt-wise, elderly dependency is found higher in mountain but other ageing indicators are at higher levels in hills. Development region-wise, western region shows relatively more ageing stress compared to other regions except that median age is found highest in the central region. Additionally, two semi-log statistical models that fit well are also built to associate percent elderly populations of Nepal with crude birth rate based upon population censuses of Nepal.     

Susceptibility of 5-methyltetrahydrofolic acid to heat and microencapsulation to enhance its stability during extrusion processing

Folic acid is a common form of folate used for food fortification to prevent the incidence of neural birth defects among others. However, 5-methyltetrahydrofolic acid (5-MTHF) is considered, a better alternative to folic acid and is less likely to mask the symptoms of B₁₂ deficiency in older populations. Also it is less bioavailable, and present in very low amount in foods. Fortification of foods with 5-MTHF is considered problematic, because it is highly sensitive to normal food processing operations. A comparative study on the thermal stability of folic acid and 5-MTHF in various liquid model food matrices such as milk, soymilk, starch–water and water during boiling and autoclaving at various time intervals was performed. Thermal degradation of 5-MTHF was more severe than folic acid in all food matrices e.g., almost 70% loss of 5-MTHF vs 17% loss of folic acid. Microencapsulation of 5-MTHF is considered to improve the stability of 5-MTHF during processing. A combination of pectin (P) and sodium alginate (A) at three different proportions (P60:A40, P70:A30, P80:A20) were employed for encapsulating 5-MTHF by spray drying. Microcapsules with the highest loading efficiency of 60% of vitamin (from P80:A20) and unencapsulated 5-MTHF powder was incorporated into starch and extruded at six different temperatures (100, 110, 120, 130, 140, 150 °C). The 5-MTHF had better stability (84–94.5% retention) compared to the free form (65.3–83.2%) in all extruded products. The effectiveness of encapsulation was more evident at higher extrusion temperatures.     

Low-Temperature Plasma-Assisted Nitrogen Fixation for Corn Plant Growth and Development

Nitrogen fixation is crucial for plants as it is utilized for the biosynthesis of almost all biomolecules. Most of our atmosphere consists of nitrogen, but plants cannot straightforwardly assimilate this from the air, and natural nitrogen fixation is inadequate to meet the extreme necessities of global nutrition. In this study, nitrogen fixation in water was achieved by an AC-driven non-thermal atmospheric pressure nitrogen plasma jet. In addition, Mg, Al, or Zn was immersed in the water, which neutralized the plasma-treated water and increased the rate of nitrogen reduction to ammonia due to the additional hydrogen generated by the reaction between the plasma-generated acid and metal. The effect of the plasma-activated water, with and without metal ions, on germination and growth in corn plants (Zea Mays) was investigated. The germination rate was found to be higher with plasma-treated water and more efficient in the presence of metal ions. Stem lengths and germination rates were significantly increased with respect to those produced by DI water irrigation. The plants responded to the abundance of nitrogen by producing intensely green leaves because of their increased chlorophyll and protein contents. Based on this report, non-thermal plasma reactors could be used to substantially enhance seed germination and seedling growth.     

Effect of protein concentration on the surface composition,water sorption and glass transition temperature of spray-dried skim milk powders

The effects of dilution of protein content in skim milk (34–8.5% protein content), by lactose addition, on the surface composition, water sorption property and glass transition temperatures of spray-dried powders were investigated. The X-ray photoelectron spectroscopy (XPS) study of spray-dried powders showed preferential migration of proteins toward the surface of the milk particles whereas the lactose remained in the bulk. Sorption studies showed that the lower protein concentration in milk powders is linked to an increased water adsorption property and lowering of water activity (a_w) for lactose crystallization. Analysis of glass transition temperature (T_g) of the powders sorbed at different humidities showed no distinct change in T_g values, indicating the dominant effect of lactose on the glass transition temperature of all the powders.     

Influence of 8‐bit vs. 11‐bit digital displays on observer performance and visual search: A multi‐center evaluation

Abstract— Medical‐grade monochrome monitors typically display 8 bits of data. This study determined if 11‐bit displays could improve observer performance and decrease use of window/level. 8‐ and 11‐bit displays from three manufacturers were used at three sites. Six radiologists at each site viewed 100 DR chest images (half with a pulmonary nodule) on both displays. Decisions, confidence, nodule location, viewing time, and window/level use were recorded. There was no significant difference in ROC Az as a function of bit depth. The average Az with 8 bits was 0.8284 and with 11 bits was 0.8253. There was a significant difference in viewing time favoring the 11‐bit displays. Window/level use did not differ. Eye position was recorded on a subset of images at one site. Cumulative dwell times for each decision category were lower with the 11‐bit than with the 8‐bit display. When tested with t‐tests for paired observations, the TP (t = 1.452, p = 0.1507), FN (t = 0.050, p = 0.9609), and FP (t = 0.042, p = 0.9676) were not statistically significant. The difference in the TN decisions was statistically significant (t = 1.926, p = 0.05). 8‐bit displays will not impact negatively diagnostic accuracy, but using 11‐bit displays may improve workflow efficiency.