Emission, fate and effects of soluble silicates (waterglass) in the aquatic environment

Soluble silicates, commercially known as waterglass, are among the largest volume synthetic chemicals in the world. Silicon from waterglass is rapidly transformed to the biologically active orthosilicic acid (referred to as dissolved silicate). This paper aims to assess the impact of waterglass on the aquatic environment in Western Europe. The emission to surface waters from the four most relevant application areas, household detergents, pulp and paper production, water and wastewater treatment, and soil stabilization, is estimated to be ca. 88-121 kton of SiO2 per year. This is a small fraction (<2%) of the estimated total amount of dissolved silicate transported by rivers to the oceans. Locally, increases in dissolved silicate concentration will decrease the ratios of N:Si and P:Si, which could influence phytoplankton species composition and favor the growth of diatoms over other groups of algae. Significant adverse effects in aquatic ecosystems are not expected.     

Relationships between milk coagulation property traits analyzed with different methodologies

Milk coagulation properties (MCP) analysis is performed using a wide range of methodologies in different countries and laboratories, using different instruments, coagulant activity in the milk, and type of coagulant. This makes it difficult to compare results and data from different research. The aims of this study were to propose a method for the transformation of values of rennet coagulation time (RCT) and curd firmness (a₃₀) and to predict the noncoagulation (NC) probability of milk samples analyzed using different methodologies. Individual milk samples were collected during the morning milking in October 2010 from each of 165 Holstein-Friesian dairy cows in 2 freestall barns in Italy, and sent to 3 laboratories for MCP analysis. For each laboratory, MCP analysis was performed using a different methodology: A, with a computerized renneting meter instrument using 0.051 international milk clotting units (IMCU)/mL of coagulant activity; B, with a Lattodinamografo (Foss-Italia, Padova, Italy) using 0.051 IMCU/mL of coagulant activity; and C, with an Optigraph (Ysebaert, Frépillon, France) using 0.120 IMCU/mL of coagulant activity. The relationships between MCP traits were analyzed with correlation and regression analyses for each pair of methodologies. For each MCP trait, 2 regression models were applied: model 1 was a single regression model, where the dependent and independent variables were the same MCP trait determined by 2 different methodologies; in model 2, both a₃₀ and RCT were included as independent variables. The NC probabilities for laboratories with the highest number of NC samples were predicted based on the RCT and a₃₀ values measured in the laboratories with lower number of NC samples using logistic regression and receiver operating characteristic analysis. The percentages of NC samples were 4.2, 11.5, and 0.6% for A, B, and C, respectively. The transformation of MCP traits was more precise with model 1 for RCT (R²: 0.77-0.82) than for a₃₀ (R²: 0.28-0.63). The application of model 2 was needed when the C measurements were transformed into the other scales. The analyses of NC probabilities of milk samples showed that NC samples from one methodology were well distinguishable (with an accuracy of 0.972-0.996) based on the rennet coagulation time measured with the other methodology. A standard definition for MCP traits analysis is needed to enable reliable comparisons between MCP traits recorded in different laboratories and in different animal populations and breeds.     

Field observation of tornadic supercells by multiple autonomous fixed‐wing unmanned aircraft

This paper presents the results of the design and field deployment of multiple autonomous fixed‐wing unmanned aircraft into supercell thunderstorms. As part of a field campaign in Spring 2019, up to three fixed‐wing unmanned aircraft were deployed simultaneously into different regions of supercell thunderstorms, To learn more about the atmospheric conditions that lead to the formation of tornadoes. Successful field deployment is attributed to (a) a nomadic concept of operations that allows the unmanned aircraft system team and science team to work seamlessly together while satisfying all aviation regulations and (b) the ruggedized RAAVEN unmanned aircraft system with modular features that favor rapid, ease‐of‐use over the brute strength of previous designs. The concept of operations and the unmanned aircraft system are described along with results from a 4 day window where four storms were sampled: two of these storms were tornadic (formed tornadoes before, during, or after being sampled) and two were not. These results validate the feasibility of nomadic operation of multiple unmanned aircraft simultaneously in severe weather conditions. Further, the successful field deployments demonstrate the importance of the modular unmanned aircraft design.     

Comparison of the metabolic profiles of noncoagulating and coagulating bovine milk

We hypothesize that, through milk composition and different milk metabolites, it is possible to characterize the technological properties (e.g., coagulation) of milk. In this research, liquid chromatography mass spectrometry was used to obtain profiles of low molecular weight organic compounds in 143 milk samples. The metabolic profiles of milk from cows were correlated with their coagulation properties. Using multivariate data analysis methods, we demonstrated that the metabolic profiles of the milk were correlated with coagulation ability. Several marker ions responsible for differential coagulation were found. Although not all affected metabolites could be identified, the most significant differences were found for carnitine and oligosaccharides. Exploitation of these results may increase the use of biomarkers to assess the coagulation ability of milk. This study represents the first large-scale metabolomic profiling of noncoagulating and coagulating bovine milk samples in Estonia.     

Adipose tissue insulin receptor and glucose transporter 4 expression,and blood glucose and insulin responses during glucose tolerance tests in transition Holstein cows with different body condition

Glucose uptake in tissues is mediated by insulin receptor (INSR) and glucose transporter 4 (GLUT4). The aim of this study was to examine the effect of body condition during the dry period on adipose tissue mRNA and protein expression of INSR and GLUT4, and on the dynamics of glucose and insulin following the i.v. glucose tolerance test in Holstein cows 21 d before (d ?21) and after (d 21) calving. Cows were grouped as body condition score (BCS) ≤3.0 (thin, T; n = 14), BCS = 3.25 to 3.5 (optimal, O; n = 14), and BCS ≥3.75 (overconditioned, OC; n = 14). Blood was analyzed for glucose, insulin, fatty acids, and β-hydroxybutyrate concentrations. Adipose tissue was analyzed for INSR and GLUT4 mRNA and protein concentrations. During the glucose tolerance test 0.15 g/kg of body weight glucose was infused; blood was collected at ?5, 5, 10, 20, 30, 40, 50, and 60 min, and analyzed for glucose and insulin. On d ?21 the area under the curve (AUC) of glucose was smallest in group T (1,512 ± 33.9 mg/dL × min) and largest in group OC (1,783 ± 33.9 mg/dL × min), and different between all groups. Basal insulin on d ?21 was lowest in group T (13.9 ± 2.32 µU/mL), which was different from group OC (24.9 ± 2.32 µU/mL. On d ?21 the smallest AUC 5–60 of insulin in group T (5,308 ± 1,214 µU/mL × min) differed from the largest AUC in group OC (10,867 ± 1,215 µU/mL × min). Time to reach basal concentration of insulin in group OC (113 ± 14.1 min) was longer compared with group T (45 ± 14.1). The INSR mRNA abundance on d 21 was higher compared with d ?21 in groups T (d ?21: 3.3 ± 0.44; d 21: 5.9 ± 0.44) and O (d ?21: 3.7 ± 0.45; d 21: 4.7 ± 0.45). The extent of INSR protein expression on d ?21 was highest in group T (7.3 ± 0.74 ng/mL), differing from group O (4.6 ± 0.73 ng/mL), which had the lowest expression. The amount of GLUT4 protein on d ?21 was lowest in group OC (1.2 ± 0.14 ng/mL), different from group O (1.8 ± 0.14 ng/mL), which had the highest amount, and from group T (1.5 ± 0.14 ng/mL). From d ?21 to 21, a decrease occurred in the GLUT4 protein levels in both groups T (d ?21: 1.5 ± 0.14 ng/mL; d 21: 0.8 ± 0.14 ng/mL) and O (d ?21: 1.8 ± 0.14 ng/mL; d 21: 0.8 ± 0.14 ng/mL). These results demonstrate that in obese cows adipose tissue insulin resistance develops prepartum and is related to reduced GLUT4 protein synthesis. Regarding glucose metabolism, body condition did not affect adipose tissue insulin resistance postpartum.     

Trans Fatty Acid Contents in Selected Dietary Fats in the Estonian Market

In response to public concern, this study assessed the fatty acid (FA) composition of blended spreads, margarines and shortenings in the Estonian retail market in 2011. Special attention was paid to the trans fatty acids (TFA) composition. The changes in these characteristics of selected dietary fats in the market over recent years are also presented. Twenty-six edible fat brands, available in the Estonian retail market in 2011, were purchased and FA compositions were analyzed by chromatography. Saturated fatty acids (SFA) were the dominant group of FAs for all blended spreads (49.6 to 65.8%), and for the majority of shortenings (from 21.1 to 54.6%). Cis monounsaturated fatty acids (MUFA) were the dominant group of FAs for the majority of margarines, ranging from 25.3% to 50.5%. The total TFA for blended spreads varied from 1.18% to 9.08%, for margarines from 0.04% to 34.96% and for shortenings from 0.14% to 39.50%. Octadecenoic (C18:1) isomers were the main TFA found. Compared to 2008/2009, the industrially produced TFA (IP-TFA) content in several of the dietary fat brands was much reduced in 2011. This voluntary reformulation was probably a response to consumer demand associated with a public health campaign directed against IP-TFA in Estonian foods, and were mainly achieved by replacing TFA with SFA C12:0-C16:0. Practical Application: Present paper is directed toward public health related institutions and food industries producing foods with potentially high contents of trans fatty acids (TFA). According to the public concern TFA content in domestic blended spreads has declined significantly over the past 3 y in Estonia. The reduction in the TFA content was achieved by replacing TFA with saturated fatty acids (SFA) (C12:0-C16:0). To shift food composition toward healthier product formulations, mandatory labeling of the sum of IP-TFA and SFA (C12:0-C16:0) was recommended.     

The significance of the rubber damping peak in rubber-modified polymers

Dynamic mechanical properties have been used as the basis for some important conclusions with regards to the physical properties of rubber-modified high-impact polymers. This paper attempts to show that conclusions of this type should be limited to fairly narrow groupings of polymers. Since the size, shape, and position on the temperature scale of a damping peak are influenced by composition, morphology, and method of polymer preparation, the significance of the damping peak associated with the rubber phase of the polymer has probably been generalized to too great an extent. Two examples of polymer groupings are given to illustrate the need for caution in attaching significance to the dynamic mechanical properties of polymers. Also given are two fairly narrow polymer groupings to show to what extent dynamic mechanical properties can be used for a correlation with impact strength and rubber concentration.     

Finite element method for piezoelectric vibration

A finite element formulation which includes the piezoelectric or electroelastic effect is given. A strong analogy is exhibited between electric and elastic variables, and a ‘stiffness’ finite element method is deduced. The dynamical matrix equation of electroelasticity is formulated and found to be reducible in form to the well-known equation of structural dynamics, A tetrahedral finite element is presented, implementing the theorem for application to problems of three-dimensional electroelasticity.