The path from β-carotene to carlactone, a strigolactone-like plant hormone

Strigolactones, phytohormones with diverse signaling activities, have a common structure consisting of two lactones connected by an enol-ether bridge. Strigolactones derive from carotenoids via a pathway involving the carotenoid cleavage dioxygenases 7 and 8 (CCD7 and CCD8) and the iron-binding protein D27. We show that D27 is a β-carotene isomerase that converts all-trans-β-carotene into 9-cis-β-carotene, which is cleaved by CCD7 into a 9-cis-configured aldehyde. CCD8 incorporates three oxygens into 9-cis-β-apo-10'-carotenal and performs molecular rearrangement, linking carotenoids with strigolactones and producing carlactone, a compound with strigolactone-like biological activities. Knowledge of the structure of carlactone will be crucial for understanding the biology of strigolactones and may have applications in combating parasitic weeds.     

Influence of industrial and alternative farming systems on contents of sugars, organic acids, total phenolic content, and the antioxidant activity of red beet (Beta vulgaris L. ssp. vulgaris Rote Kugel)

The contents of sugars, organic acids, total phenolic content, and the antioxidant activity were quantified in the flesh of red beet from conventional (CON), integrated (INT), organic (ORG), biodynamic (BD), and control farming systems using established methods. Significant differences were measured for malic acid, total phenolic content (TPC), and total antioxidant activity, where malic acid content ranged from 2.39 g kg(-1) FW (control) to 1.63 g kg(-1) FW (CON, ORG, and INT). The highest TPC was measured in BD and control samples (0.677 and 0.672 mg GAE g(-1), respectively), and the lowest in CON samples (0.511 mg GAE g(-1)). Antioxidant activity was positively correlated with TPC (r2=0.6187) and ranged from 0.823 μM TE g(-1) FW to 1.270 μM TE g(-1) FW in CON and BD samples, respectively, whereas total sugar content ranged from 21.03 g kg(-1) FW (CON) to 31.58 g kg(-1) FW (BD). The importance of sugars, organic acids, phenols, and antioxidants for human health, as well as for plant resilience and health, gained from this explorative study, is discussed and put into perspective.     

The distribution of <Emphasis Type="Italic">Obolodiplosis robiniae</Emphasis> on black locust in Slovakia

For the first time during October 2006, the occurrence of Obolodiplosis robiniae (Haldeman 1847) (Diptera: Cecidomyiidae) was recorded on the black locust (Robinia pseudoacacia L.) in Slovakia. During 2007, field surveys were undertaken to determine the distribution of the species and the infestation ratio at different locations. One year after its first discovery, O. robiniae was found throughout southern Slovakia. The gall midge was observed in 148 out of 161 checked locations. The infestation ratio of single leaves varied from 4 to 100%. The infestation ratio of the black locust tree was evaluated during May–June, July–August, and September–October, and accounted for 15–39, 9–53, and 6–49%, respectively. The most frequent infestation ratio fluctuated from 10 to 30% (115 locations). The highest infestation was recorded during July–August. Greater infestation was prevalent in the larger settlements than it was in the countryside. The gall midge was also recorded on R. viscosa Vent. Although the results show that O. robiniae is nowadays an usual insect with high potential to become an important pest of ornamental black locust or biological control agent against weedy black locust in southern Slovakia, the species do not appear to have reached pest status until now.     

Managing supplementary feeding for avian scavengers: Guidelines for optimal design using ecological criteria

Current European sanitary laws are promoting the concentration of domestic livestock carcasses in limited locations called ‘vulture restaurants’ or supplementary feeding stations in order to safeguard human health. However, this type of food concentration could lead to monopolization by a few, large dominant species. Management guidelines are urgently needed to ensure that potentially less competitive and more endangered scavengers can also benefit from this resource, considering that once abundant carcasses are now absent from the field. Here, we assess factors affecting the abundance of six avian scavenger species at 17 feeding stations in northern Spain, considering aspects such as carrion availability, physiographic features, humanization, presence of heterospecifics and densities of scavengers during both winter and summer seasons. Results indicate that conditions for interspecific facilitatory processes are possible at low numbers (<100 individuals) of griffon vultures (Gyps fulvus). Otherwise, the other avian scavengers are excluded. In a few cases, spatio-temporal patterns of segregation become apparent. Differences in the size of carcasses supplied to feeding stations as well as the local characteristics influence the balance of species at these points and, therefore, how species of conservation concern use feeding stations. Future legislation should encourage the opening of numerous feeding stations supplied with low quantities of food to mimic the original condition of temporal and spatial unpredictability of carcasses and to maintain ecological relationships within the scavenger guild.     

Comparison of barometric whole body plethysmography and its derived parameter enhanced pause (PENH) with conventional respiratory mechanics in healthy Beagle dogs

The purpose of the study was to compare barometric whole body plethysmography (BWBP) and its derived parameter, enhanced pause (PENH), with conventional respiratory mechanics measurements. Resistance (RL), dynamic compliance (Cdyn) and pleural pressure changes were measured in six healthy anaesthetised Beagle dogs using a pneumotachograph and oesophageal balloon technique consecutive to BWBP-derived variables. Upper airway airflow limitation was established (1) by a filter or (2) by insertion of a narrow endotracheal tube. Bronchoconstriction was induced by nebulisation of carbachol at increasing concentrations until PENH exceeded 300% baseline. Upper airway narrowing significantly increased resistance (baseline RL 2.0+/-0.3, RL filter 11.8+/-3.2, RL luminal narrowing 21.1+/-2.3cm H(2)O/L/s; P <0.03), whereas PENH did not change significantly (baseline PENH 0.55+/-0.17, PENH filter 0.49+/-0.10; PENH luminal narrowing 0.50+/-0.18; P >0.05). Carbachol-induced bronchoconstriction caused a significant increase in PENH (baseline PENH 0.43+/-0.14, PENH carbachol 2.62+/-2.14; P <0.02) and resistance (baseline RL 2.1+/-0.3, RL carbachol 28.8+/-13.0 cm H2O/L/s; P <0.01), and a pronounced drop in compliance (baseline Cdyn 163.3+/-73.9, Cdyn carbachol 9.7+/-2.9mL/cmH2O; P <0.02). It was concluded that BWBP detects airflow limitation due to bronchoconstriction but not due to upper airway obstruction in healthy dogs. BWBP represents a valid, although not very sensitive screening tool for respiratory function testing.     

Changes in Ensembles’ Thermal Insulation According to Garment’s Fit and Length Based on Athletic Figure

The purpose of this paper is to analyse the impact of design solutions on the thermal insulation of the garments and the ensembles. Previous studies investigated the microclimatic air gaps and volumes, however only under the first - and the second - layered clothing. Since none of the previous studies covered three - layered ensembles, in this study ensembles were accompanied by jackets of different fit and length to investigate the ensembles’ thermal insulation. Variants of bomber jacket differ in the amount of the ease allowance, while variants of the parka differ in length. The thermal insulation of the ensembles increased for 21.6 to 59.7 % when one of the jacket variants was added as the outerwear garment. A threshold volume, after which the thermal insulation will start to decrease due to convection, wasn’t determined for the outerwear third - layered garments nor was the impact of the length of the garment on the thermal insulation clearly stated. This study involved laboratory testing of garments and ensembles by 3D body scanning and thermal manikin measurements. To evaluate the volume of the microclimatic air volume the accurate 3D body scanning was used and the impact of the microclimatic volume on the ensemble’s insulation was tested. The thermal insulation for the selected outerwear garments and afterwards ensembles was measured by resting thermal manikin. Analysis of the results obtained from tests, showed that the garments’ fit and length can be used to model the overall thermal insulation of the ensembles. The ensembles insulation enlargement was measured for microclimatic volumes up to 33.57 dm³ (measured with ensembles accompanied with bomber jacket). The study proved that the limiting microclimatic volume is greater for three - layered clothing, than previously reported. The overall ensembles’ insulation increased simultaneously with the length enlargement (measured with ensembles accompanied with parka jacket). Findings will be of help in the future research on garments and ensembles thermal properties modelled through the design process and the construction.     

Prevalence of stocked whitefish in River Kemijoki,Finland, inferred by micro X‐ray fluorescence analysis of otoliths

Micro X‐ray fluorescence (µ‐XRF) analysis of otoliths was evaluated as a method to estimate the proportion of stocked one‐summer‐old whitefish Coregonus lavaretus L. in catches of adult fish (n = 20) ascending the River Kemijoki to spawn. Laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) analysis was applied as control. Polished otoliths were scanned with µ‐XRF to obtain strontium maps that were used to infer visually the provenance of the whitefish. Thirteen of the fish showed signs of being stocked as one‐summer‐old fingerlings. LA‐ICP‐MS was applied to determine the elemental composition in a spot outside the core of the otolith. The results were largely consistent with the visual inspection of the µ‐XRF mapped otoliths. In conclusion, µ‐XRF mapping successfully identified whitefish stocked as one‐summer‐old fingerlings. The vast majority of whitefish returning to the River Kemijoki to spawn were stocked fish.     

Why does rainfall affect the trend in soil carbon after converting pastures to forests?: A possible explanation based on nitrogen dynamics

When trees are planted onto former pastures, soil carbon stocks typically either remain constant or decrease, with decreases more common in regions with higher rainfall. We conducted a modelling analysis to assess whether those changes in soil carbon, especially the interaction with rainfall, could be understood through consideration of nitrogen balances. The study was based on simulations with the whole-system ecophysiological model CenW which allowed explicit modelling of both carbon and nitrogen pools and their fluxes through plants and soil organic matter.     

Emissions of ammonia,nitrous oxide and carbon dioxide from urban gardens in Niamey,Niger

Urban and peri-urban agriculture (UPA) contributes significantly to meet increasing food demands of the rapidly growing urban population in West Africa. The intensive vegetable cultivation in UPA gardens with its high nutrient inputs is often reported to operate at large surpluses of nutrients and presumably high turnover rates of organic matter (OM) and nitrogen (N) losses via emanation and leaching. Many of these claims are lacking solid data which would allow suggesting mitigation strategies. Therefore, this study aimed at quantifying gaseous emissions of ammonia (NH₃), nitrous oxide (N₂O), and carbon dioxide (CO₂) in three representative urban gardens of Niamey, Niger using a closed chamber gas monitoring system. Mean annual N emissions (NH₃-N and N₂O-N) in two gardens using river water for irrigation reached 53 and 48 kg N ha^?1 yr^?1, respectively, while 25 and 20 Mg C ha^?1 yr^?1 was lost as CO₂-C. In the garden irrigated with sewage water from the city's main wadi, N₂O was the main contributor to N losses (68%) which together with NH₃ reached 92 kg N ha^?1 yr^?1, while CO₂-C emissions amounted to 26 Mg ha^?1 yr^?1. Our data indicate that 28% of the total gaseous C emissions and 30–40% of the N emissions occur during the hot dry season from March to May and another 20–25% and 10–20% during the early rainy season from June to July. Especially during these periods more effective nutrient management strategies in UPA vegetable gardens should be applied to increase the nutrient use efficiency in UPA vegetable gardens.     

Kinetics of Zn and Cd accumulation in the isopod Porcellio scaber exposed to contaminated soil and/or food

To derive accumulation kinetics from different exposure matrices and account for the contribution of different exposure routes, the isopod Porcellio scaber was exposed to Cd and Zn, either in soil or in food, and a combination of both. Accurate uptake and elimination kinetics of Zn and Cd were determined using radioisotopes, allowing non-destructive time measurements. To describe the data, a simple kinetic model was used accounting for the internal distribution of the metals. A strong influence of the elimination kinetics, together with the metal fraction that is compartmentalized in a storage fraction, was found explaining the Cd steady-state level reached in the isopods. Zn turnover kinetics were relatively fast within the first days of exposure and elimination, followed by slow Zn kinetics from the storage compartment. The storage fraction appeared to be inert for elimination of both Zn and Cd within the experimental duration of 32 days and the fraction of metal taken up that was stored in this fraction was influenced by the uptake source. The quantity of metals taken up from soil or food depended on the concentration. For both Zn and Cd, the uptake rate constant from soil equalled the uptake rate constant from food, moreover, the uptake from both routes was shown to be additive. Therefore, it is concluded that the relative contribution of both routes (via soil or food) is explained by the partitioning of metals between soil and food.