ERG1, encoding squalene epoxidase,is located on the right arm of chromosome VII of Saccharomyces cerevisiae

The ERG1 gene of Saccharomyces cerevisiae encodes squalene epoxidase, a key enzyme in the ergosterol pathway. ERG1 is an essential gene. Disruption of the gene with URA3 results in a lethal phenotype when cells are grown under aerobic conditions, even in the presence of ergosterol. However, cells are viable in the presence of ergosterol under anaerobic growth conditions during which ergosterol is taken up by cells. Physical and genetic mapping data reveal that ERG1 is located on the right arm of chromosome VII proximal to QCR9 at a distance of 14·6 cM from ADE3.     

Detailed depth profiles of sulfate ingress into concrete measured with laser induced breakdown spectroscopy

Sulfate attack constitutes a major risk of chemical aggression for concrete and other building materials. Mainly structures exposed to sewage waters and sulfate rich soils are affected. The measurement of sulfate ingress is important for damage assessment previous to repair works and for quality assurance of the effectiveness of protecting coatings or during concrete removal.Laser induced breakdown spectroscopy is introduced for the quantitative measurement of sulfur contents in building materials, providing detailed depth profiles and imaging element distributions with 1 mm spatial resolution. Detailed statistical evaluation is possible due to the spatial resolution and the fast measurement of the method. Practical applications of the method for damage assessment are demonstrated for three different sewage plants.     

The reliability of third-party certification in the food chain: From checklists to risk-oriented auditing

In recent years, certification has become increasingly relevant for agribusiness. In Europe, substantial parts of the value chain are already being certified by standards such as the International Food Standard (IFS) or GLOBALGAP (the former EurepGap). It is not known, however, whether these approaches can de facto ensure high quality control. This article is based on a database analysis of the German certification system Quality and Safety (QS) and a workshop with the QS-certification bodies conducting 85% of all agricultural audits. It seeks to deduce the first empirical hypotheses concerned with the connection between the reliability of third-party certification and the institutional framing of standards.     

Comparison of three methods for detecting Campylobacter spp. in chilled or frozen meat

There is a demand from the meat industry as well as from public health authorities for a simple and rapid detection method for thermophilic Campylobacter spp. from food. Hence, we compared different isolation procedures for their usefulness for this purpose. Bolton enrichment medium without blood, incubated statically in stomacher bags in microaerophilic atmosphere, detected more samples positive for thermophilic Campylobacter spp. than did Preston enrichment broth in bottles with small headspace and tight caps, incubated in aerobic atmosphere. Use of an automated antigen detection system to identify enrichment cultures positive for Campylobacter spp. was as sensitive as selective agars, and reduced the detection time by 24 h. Campylobacter spp. were recovered from 18.4% of the 461 samples tested. The prevalence was highest in refrigerated poultry meat (52% of the 80 samples tested) and poultry offal (41% of the 44 samples tested).     

Insect‐Specific Production of New GameXPeptides in Photorhabdus luminescens TTO1, Widespread Natural Products in Entomopathogenic Bacteria

Discovery of new natural products by heterologous expression reaches its limits, especially when specific building blocks are missing in the heterologous host or the production medium. Here, we describe the insect‐specific production of the new GameXPeptides E–H ( 5 – 8 ) from Photorhabdus luminescens TTO1, which can be produced heterologously from expression of the GameXPeptide synthetase GxpS only upon supplementation of the production media with the missing building blocks, and thus must be regarded as the true natural products under natural conditions.     

The Balance Between Reactivity and Stability of Modified Oxide Surfaces Illustrated by the Behavior of Sulfated Zirconia Catalysts

The stability of a series of sulfated zirconia catalysts, promoted with up to 2 wt% iron or manganese, in their calcined state was investigated. Phase composition, nature of surface sulfate species, degree of hydroxylation, and butane isomerization activity changed during aging over months in various atmospheres and during milling. The metastability of small oxide particles is discussed, including literature data on alumina, titania and other oxides. Catalytically active fractions of a material easily transition into more stable, less active forms.     

Relative bioavailability of coumarin from cinnamon and cinnamon-containing foods compared to isolated coumarin: a four-way crossover study in human volunteers

Scope: Cassia cinnamon contains high levels (up to 1 %) of coumarin. Heavy consumption of this spice may result in a dose exceeding the tolerable daily intake (TDI). In this context, the question was raised whether coumarin in the plant matrix of cinnamon has the same bioavailability as isolated coumarin. Methods and results: A four‐way crossover study was performed, in which the same dose of 12 mg coumarin was administered in different formulations to 24 healthy volunteers. The relative extent of absorption measured as urinary excretion of the main metabolite 7‐hydroxycoumarin (7OHC) was found to be 62.8% for isolated coumarin in a capsule (reference), 56.0% for cinnamon in capsules, 66.1% for cinnamon tea, and 54.7% for cinnamon in rice pudding (means, n=23, observation period 8 hours). Additionally, 7OHC plasma levels were measured for 105 minutes after administration and revealed a fast absorption of coumarin from cinnamon tea leading to the highest peak concentrations. Conclusion: The relative extent of absorption of coumarin from powder of cassia cinnamon is only slightly lower than that of isolated coumarin. Therefore, the TDI of coumarin can be used for risk assessment of coumarin exposure from cinnamon‐containing meals.     

The effect of feed demand on greenhouse gas emissions and farm profitability for organic and conventional dairy farms

The reduction of product-related greenhouse gas (GHG) emissions in milk production appears to be necessary. The reduction of emissions on an individual farm might be highly accepted by farm owners if it were accompanied by an increase in profitability. Using life cycle assessments to determine the product carbon footprints (PCF) and farm-level evaluations to record profitability, we explored opportunities for optimization based on analysis of 81 organic and conventional pasture-based dairy farms in southern Germany. The objective of the present study was to detect common determining factors for low PCF and high management incomes (MI) to achieve GHG reductions at the lowest possible operational cost. In our sample, organic farms, which performed economically better than conventional farms, produced PCF that were significantly higher than those produced by conventional farms [1.61 ± 0.29 vs. 1.45 ± 0.28 kg of CO₂ equivalents (CO₂eq) per kg of milk; means ± SD)]. A multiple linear regression analysis of the sample demonstrated that low feed demand per kilogram of milk, high grassland yield, and low forage area requirements per cow are the main factors that decrease PCF. These factors are also useful for improving a farm's profitability in principle. For organic farms, a reduction of feed demand of 100 g/kg of milk resulted in a PCF reduction of 105 g of CO₂eq/kg of milk and an increase in MI of approximately 2.1 euro cents (c)/kg of milk. For conventional farms, a decrease of feed demand of 100 g/kg of milk corresponded to a reduction in PCF of 117 g of CO₂eq/kg of milk and an increase in MI of approximately 3.1 c/kg of milk. Accordingly, farmers could achieve higher profits while reducing GHG emissions. Improved education and training of farmers and consultants regarding GHG mitigation and farm profitability appear to be the best methods of improving efficiency under traditional and organic farming practices.     

Sigmoidal Indentation–Strength Characteristics of Polycrystalline Alumina

The fracture properties of a series of three polycrystailine aluminas are examined using indentationstrength and double cantilever beam techniques. The indentation-strength response is shown to be sigmoidal with concave-down behavior at small indentation loads and concave-up behavior at large indentation loads. A model is developed for the general response, combining increasing toughening by ligamentary bridging at small crack lengths and increasing residual-stress relief by lateral cracking at large indentation loads. The model is fit to the strength data and used to deconvolute the underlying toughness variation and predict the intrinsic strength of the materials. Direct measurements of toughness using the "long-crack" double cantilever beam geometry are shown to overestimate the toughness variations effective during "short-crack" strength tests.