Recommendations for implementing lung cancer screening with low-dose computed tomography in Europe

Lung cancer screening (LCS) with low-dose computed tomography (LDCT) was demonstrated in the National Lung Screening Trial (NLST) to reduce mortality from the disease. European mortality data has recently become available from the Nelson randomised controlled trial, which confirmed lung cancer mortality reductions by 26% in men and 39–61% in women. Recent studies in Europe and the USA also showed positive results in screening workers exposed to asbestos. All European experts attending the “Initiative for European Lung Screening (IELS)”—a large international group of physicians and other experts concerned with lung cancer—agreed that LDCT-LCS should be implemented in Europe. However, the economic impact of LDCT-LCS and guidelines for its effective and safe implementation still need to be formulated. To this purpose, the IELS was asked to prepare recommendations to implement LCS and examine outstanding issues. A subgroup carried out a comprehensive literature review on LDCT-LCS and presented findings at a meeting held in Milan in November 2018. The present recommendations reflect that consensus was reached

Combined use of vinasse and nitrogen as fertilizers affects nitrification, ammonification and denitrification by prokaryotes

A common agricultural practice of combining organic fertilizer vinasse (a liquid residue from sugarcane ethanol production) with mineral nitrogen (N) fertilizer promotes N losses such as greenhouse gas emissions due to the effects of physicochemical changes in soil on the microbiota inhabiting this environment. In this study, we applied microarray GeoChip v.5.0M technology to obtain a better insight into the prokaryotic communities and identify and quantify the N functional gene families associated with the N processes in sugarcane soils without N fertilizer (N0), with urea at 60 kg ha−1 (N60), and with vinasse combined with urea (NV). Soil samples were collected at 7 (T7) and 150 (T150) days after N application, corresponding to maximum and minimum nitrous oxide (N2O) emissions, respectively, for molecular and physicochemical analysis. Additionally, the metagenomes of these DNA samples, previously deposited in the MG-RAST server, were accessed to investigate the functions and taxonomic groups associated with selected gene families. The results revealed that 87% of the select gene families were significantly responsive to the fertilizer combined treatment (NV) in the 7 days after the application. The most responsive genes and processes were nitrification [with the amoA gene from ammonia-oxidizing Bacteria (AOB) and Archaea (AOA) and hao from Bacteria], ammonification (with gdh and ureC genes from Bacteria and Archaea), and denitrification (with p450nor from Eukarya). The AOA, Nitrosopumilus, and AOB, Nitrosomonas, were the groups with the greatest functions associated with nitrification, as well as a pathogenic Mycobacterium, with denitrification. The results also revealed that under N fertilizers and decreased O2 in soil, the increases in K and P nutrients can promote the growth of the halophile Archaea Natronomonas and the Bacteria Anaeromyxobacter, which can reduce N2O. In conclusion, this typical agricultural fertilization management may favor functional genes and archaeal and bacterial groups associated with N processes that have the potential to reduce environmental damage in tropical sugarcane soils

Root distribution and water use in coffee shaded with Tabebuia rosea Bertol. and Simarouba glauca DC. compared to full sun coffee in sub-optimal environmental conditions

International audienceRoot niche differentiation for optimal exploitation of resources was found in an arabica coffee agroforestry system in Nicaragua. Rooting behavior was compared in both unshaded (FS) and shaded (AFS) coffee combined with two previously untested tropical timber species (deciduous Tabebuia rosea Bertol. and evergreen Simarouba glauca DC.). The predominant andisol possesses a compacted soil layer (talpetate). The study was conducted in sub-optimal environmental conditions for coffee cultivation (455 m.a.s.l., annual mean 27 A degrees C, 1300 mm rainfall/year, 6 months dry season) in Nicaragua. Twelve and five trenches 200 cm deep were dug in AFS and FS respectively. Roots per unit area were counted on two perpendicular soil faces. Volumetric water was measured continuously over 2 years by using 45 reflectometers in different soil layers. The talpetate varied greatly in depth, thickness and physical structure. Coffee fine roots were more abundant than tree roots and were concentrated in the shallower strata (0-80 cm) whilst tree roots proliferated more below 100 cm. The S. glauca root system was denser below 100 cm than T. rosea root system. There was no meaningful difference in coffee root counts in FS and under T. rosea, but coffee root counts were higher near S. glauca trees. 2012 and 2014 had mild dry seasons and whole profile soil water content was similar in FS and AFS, but in the 2013 severe dry period volumetric water and water uptake were lower in AFS than in FS. This indicates that the normal advantage of greater soil exploration in AFS was cancelled presumably due to continued water uptake by deep rooting trees whereas the FS still had available water

Interaction strengths in food webs: issues and opportunities

1. Recent efforts to understand how the patterning of interaction strength affects both structure and dynamics in food webs have highlighted several obstacles to productive synthesis. Issues arise with respect to goals and driving questions, methods and approaches, and placing results in the context of broader ecological theory. 2. Much confusion stems from lack of clarity about whether the questions posed relate to community-level patterns or to species dynamics, and to what authors actually mean by the term “interaction strength”. Here, we describe the various ways in which this term has been applied and discuss the implications of loose terminology and definition for the development of this field. 3. Of particular concern is the clear gap between theoretical and empirical investigations of interaction strengths and food web dynamics. The ecological community urgently needs to explore new ways to estimate biologically reasonable model coefficients from empirical data, such as foraging rates, body size, metabolic rate, biomass distribution, and other species traits. 4. Combining numerical and analytical modeling approaches should allow exploration of the conditions under which different interaction strengths metrics are interchangeable with regard to relative magnitude, system responses, and species identity. 5. Finally, the prime focus on predator-prey links in much of the research to date on interaction strengths in food webs has meant that the potential significance of non-trophic interactions, such as competition, facilitation, and biotic disturbance, have been largely ignored by the food web community. Such interactions may be important dynamically and should be routinely included in future food web research programmes