Studies on the inactivation of viruses by ethylene oxide

Under conditions designed to imitate heavy natural contamination of equipment, animal cages, etc. virus was exposed to ethylene oxide treatment.The effect on strains of the enterovirus types Coxsackie B₃ and ECHO 11, of vaccinia virus and of Newcastle disease virus was studied. The viruses were all inactivated by a treatment which was considered sufficient from a bacteriological point of view.Keyword: ethylene oxide, virus inactivation     

Impact of relationships between test and training animals and among training animals on reliability of genomic prediction

One of the factors affecting the reliability of genomic prediction is the relationship among the animals of interest. This study investigated the reliability of genomic prediction in various scenarios with regard to the relationship between test and training animals, and among animals within the training data set. Different training data sets were generated from EuroGenomics data and a group of Nordic Holstein bulls (born in 2005 and afterwards) as a common test data set. Genomic breeding values were predicted using a genomic best linear unbiased prediction model and a Bayesian mixture model. The results showed that a closer relationship between test and training animals led to a higher reliability of genomic predictions for the test animals, while a closer relationship among training animals resulted in a lower reliability. In addition, the Bayesian mixture model in general led to a slightly higher reliability of genomic prediction, especially for the scenario of distant relationships between training and test animals. Therefore, to prevent a decrease in reliability, constant updates of the training population with animals from more recent generations are required. Moreover, a training population consisting of less‐related animals is favourable for reliability of genomic prediction.     

Analysis of Factors that Influence Kernel Weight of Wheat Infected by Septoria nodorum

Several methods for determining yield reduction resulting from Septoria nodorum blotch have appeared in the literature during the past decade. These methods varied from the measurement of effects of disease on components of yield to calculation of area of symptoms on certain leaves at different growth stages. We analyzed data from a uniform group of wheat entries in the USDA Septoria nursery that had been grown in seven locations in North America and Europe during the years 1982–1987. Symptom severity and height of symptom on the plant were compared to kernel number and kernel weight. Location, year-within-location and genotype were also considered. In the context of this study, we concluded that location, and year-within-location are the most important factors determining yield reduction (as measured by relative kernel weight). Selection directly for components of yield is quite effective, but selection by means of disease symptoms is often not correlated with yield. We also conclude that specific methods for relating symptoms to yield reduction that are applicable to a particular location are probably useful and appropriate for that location only.     

Cellular localization of somatomedin (insulin-like growth factor) messenger RNA in the human fetus

The somatomedins or insulin-like growth factors (IGFs) are synthesized in many organs and tissues, but the specific cells that synthesize them in vivo have not been defined. By in situ hybridization histochemistry, IGF I (somatomedin C) and IGF II messenger RNAs were localized to connective tissues or cells of mesenchymal origin in 14 organs and tissues from human fetuses. IGF messenger RNAs were localized to perisinusoidal cells of liver, to perichondrium of cartilage, to sclera of eye, and to connective tissue layers, sheaths, septa, and capsules of each organ and tissue. All of the hybridizing regions are comprised predominantly of fibroblasts or other cells of mesenchymal origin. Because these cells are widely distributed and anatomically integrated into tissues and organs, they are ideally located for production of IGFs, which may exert paracrine effects on nearby target cells.     

Influence of daylength and temperature during formation of seed potatoes on subsequent growth and yields under long day conditions

Production of high quality seed potatoes is normally favoured by a cool climate with minor pest problems. Growth chamber studies aimed to reveal if daylengths (12 and 24 hrs) and temperatures (18/12 and 12/9°C day/night) during production also might influence progeny growth. Results showed no significant carry-over effect from daylength conditions, while growth vigour and yields were affected by parent plant growth temperature. Further experiments, including a greater range of temperatures, different cultivars and measurements of physiological age, are required to discuss theoretical and practical implications of the results.     

First biogeographical survey of Artemia in Tanzania

ABSTRACT

In an Artemia survey conducted along the coast of Tanzania between March and July 2017, 32 salt pans in Tanga, Dar es salaam, Pwani, Lindi, and Mtwara were assessed. Of all visited salt pans, 16 (50%) had either Artemia biomass or cysts or both. Body length ranged from 4.0 mm to 9.5 mm, while the mean and modal lengths were 6.2 mm and 6.0 mm, respectively. Temperature ranged from 27.2°C to 48.7°C, salinity from 20 g L^?1 to >140 g L^?1, pH from 5.8 to 7.8, dissolved oxygen (DO) from 3.1 mg L^?1 to 4.9 mg L^?1, water depth from 10 cm to 75 cm and conductivity from 42.0 ms cm^?1 to 176.6 ms cm^?1. A bisexual population of Artemia franciscana is suggested. Observed cyst states included concave, biconcave, spherical and cracking cysts. This is the first to report on the occurrence of Artemia in Tanzania.     

Evaluation of an on-the-go technology for soil pH mapping

Since conventional sampling and laboratory soil analysis do not provide a cost effective capability for obtaining geo-referenced measurements with adequate frequency, different on-the-go sensing techniques have been attempted. One such recently commercialized sensing system combines mapping of soil electrical conductivity and pH. The concept of direct measurement of soil pH has allowed for a substantial increase in measurement density. In this publication, soil pH maps, developed using on-the-go technology and obtained for eight production fields in six US states, were compared with corresponding maps derived from grid sampling. It was shown that with certain field conditions, on-the-go mapping can significantly increase the accuracy of soil pH maps and therefore increase the potential profitability of variable rate liming. However, in many instances, these on-the-go measurements need to be calibrated to account for a field-specific bias. After calibration, the overall error estimate for soil pH maps produced using on-the-go measurements was less than 0.3 pH, while non-calibrated on-the-go and conventional field average and grid-sampling maps produced errors greater than 0.4 pH.     

Antioxidant properties of carnosine re-evaluated in a ferrylmyoglobin model system and in cooked pork patties

The antioxidative effect of purified carnosine (i.e., separated from the common contaminant hydrazine) has been evaluated in two systems: (i) Carnosine was found to possess poor reducing properties toward the prooxidant ferrylmyoglobin; at pH approximately 5 the presence of carnosine did not increase the rate of reduction of MbFe(IV)=O compared to autoreduction, whereas at pH 7.4 the rate constant for reduction by carnosine was 0.010 +/- 0.002 M(-1).s(-1) (I = 0.16; 25.0 degrees C). (ii) In cooked pork patties prepared from meat (longissimus dorsi and masseter) with purified or nonpurified carnosine added, the effect of purified carnosine was insignificant when compared to control patties, whereas patties with carnosine contaminated with hydrazine had a lower oxidation level than patties with purified carnosine. Carnosine is concluded not to deactivate the prooxidant ferrylmyoglobin and not to have any antioxidative effect in cooked pork.