Luminescence in Slipped and Dislocation-Free Laser-Annealed Silicon

Photoluminescence of cw laser-annealed silicon shows a dramatic difference in electronic behavior of the reconstructed material depending upon either creation or suppression of dislocations. Beyond a critical exposure time slip appears, and the luminescence of these samples is dominated by dislocation-related defect levels

Picosecond Laser Pulse Irradiation of Crystalline Silicon

Morphology changes introduced by picosecond laser pulses at λ = 532 nm and 355 nm in (111) and (100) silicon samples are studied by means of optical and high-voltage electron microscopy. Depending on energy fluence, orientation and wavelength, amorphous or highly defective regions may be created. From an analysis of damage thresholds and damage depth distributions it is concluded that melting and energy confinement precedes the formation of the structural changes

Trends and geographic variation in adverse impacts of nitrogen use in Europe on human health, climate, and ecosystems: a review

•This paper presents a review of the trends and geographic variation of impacts of reactive nitrogen (N) inputs on in Europe through impacts on air, soil and water quality. It illustrates those impacts, by assessing temporal and spatial variation in air, soil and water quality indicators and their exceedances of critical thresholds in view of impacts on human health, terrestrial and aquatic ecosystems, during 1990-2019. Trends are derived from regular inventory and monitoring data and from simulated trends in air quality using the EMEP model. •Well quantified adverse impacts of increased N use are: (i) the effects on human health due to increased tropospheric concentrations of NOx and ozone, and N-induced increases in fine particulate matter, (ii) the contribution of N2O to climate change and stratospheric ozone depletion, (iii) the loss of plant and faunal diversity both in terrestrial and aquatic ecosystems via direct and soil mediated impacts, (iv) the acidification of forest soils, with impacts on tree forest nutrition, tree growth and tree vitality, and (v) the eutrophication of marine ecosystems, and associated biodiversity loss and occurrence of harmful algae blooms. •Over the period 1990-2019, N inputs to agriculture stayed relatively constant, but the emissions of ammonia (NH3) decreased by 27%, while emissions of nitrogen oxides (NOx) decreased by 57%. In response to those reductions, concentrations of NOx, and of N in particulate matter also declined, although less than 50%. In contrast, the reduction in NOx-induced ozone concentrations and ozone related indicators (AOT40, SOMO35 and POD) was much less (ca 15-20%). Exceedances of critical ozone concentrations for human health and of critical AOT40 and POD vales for vegetation reduced in a similar order of magnitude. Despite decreasing NH3 emissions, NH3 concentrations showed a slight and steady increase from 1995 onwards, due to the large reduction in SOx emissions. Nitrogen deposition and exceedances of critical N loads for terrestrial ecosystems decreased by ca 60%, but the area exceeding critical N loads only reduced by ca 10%. Unlike N, the area exceeding critical acid loads has declined by more than 90% due to high reduction in SOx and NOx emissions. Trends in nitrate (NO3) concentrations in groundwater varied across Europe, but showed overall limited changes over the last two decades. However, N concentrations in surface water and the area exceeding critical levels in view of aquatic biodiversity has decreased and the same holds for N concentrations in coastal regions. Nevertheless, the eutrophication condition of coastal waters has overall not improved due to adverse impacts of elevated phosphorus inputs. Finally the negative impacts of N induced N2O emissions on climate are estimated to be outweighed by the positive effects of N induced CO2 sequestration, mainly in forests, and this holds for the whole period 1990-2019. Nitrogen hotspots, being areas with high exceedances in critical levels and loads of N compounds in air and water, are concentrated in intensive agricultural areas with high livestock densities and in urban region with strong industrial and traffic activities. •Cost-benefit analysis shows that environmental costs of reactive N release to the environment are substantial and tend to exceed the direct economic benefits for agriculture. Given the relevance of N for safeguarding food production it is key to develop integrated and targeted plant nutrition strategies following a food system approach and practices that minimize trade-offs between productivity and the environment. In addition, targeted strategies to further reduce NOx emissions are needed to reduce air quality related health and biodiversity impacts

Genome-Wide Genotype-Expression Relationships Reveal Both Copy Number and Single Nucleotide Differentiation Contribute to Differential Gene Expression between Stickleback Ecotypes

Repeated and independent emergence of trait divergence that matches habitat differences is a sign of parallel evolution by natural selection. Yet, the molecular underpinnings that are targeted by adaptive evolution often remain elusive. We investigate this question by combining genome-wide analyses of copy number variants (CNVs), single nucleotide polymorphisms (SNPs), and gene expression across four pairs of lake and river populations of the three-spined stickleback (Gasterosteus aculeatus). We tested whether CNVs that span entire genes and SNPs occurring in putative cis-regulatory regions contribute to gene expression differences between sticklebacks from lake and river origins. We found 135 gene CNVs that showed a significant positive association between gene copy number and gene expression, suggesting that CNVs result in dosage effects that can fuel phenotypic variation and serve as substrates for habitat-specific selection. Copy number differentiation between lake and river sticklebacks also contributed to expression differences of two immune-related genes in immune tissues, cathepsin A and GIMAP7. In addition, we identified SNPs in cis-regulatory regions (eSNPs) associated with the expression of 1,865 genes, including one eSNP upstream of a carboxypeptidase gene where both the SNP alleles differentiated and the gene was differentially expressed between lake and river populations. Our study highlights two types of mutations as important sources of genetic variation involved in the evolution of gene expression and in potentially facilitating repeated adaptation to novel environments

Safe and just Earth system boundaries

The stability and resilience of the Earth system and human well-being are inseparably linked 1-3, yet their interdependencies are generally under-recognized; consequently, they are often treated independently 4,5. Here, we use modelling and literature assessment to quantify safe and just Earth system boundaries (ESBs) for climate, the biosphere, water and nutrient cycles, and aerosols at global and subglobal scales. We propose ESBs for maintaining the resilience and stability of the Earth system (safe ESBs) and minimizing exposure to significant harm to humans from Earth system change (a necessary but not sufficient condition for justice) 4. The stricter of the safe or just boundaries sets the integrated safe and just ESB. Our findings show that justice considerations constrain the integrated ESBs more than safety considerations for climate and atmospheric aerosol loading. Seven of eight globally quantified safe and just ESBs and at least two regional safe and just ESBs in over half of global land area are already exceeded. We propose that our assessment provides a quantitative foundation for safeguarding the global commons for all people now and into the future

Safe and just Earth system boundaries

The stability and resilience of the Earth system and human well-being are inseparably linked1-3, yet their interdependencies are generally under-recognized; consequently, they are often treated independently4,5. Here, we use modelling and literature assessment to quantify safe and just Earth system boundaries (ESBs) for climate, the biosphere, water and nutrient cycles, and aerosols at global and subglobal scales. We propose ESBs for maintaining the resilience and stability of the Earth system (safe ESBs) and minimizing exposure to significant harm to humans from Earth system change (a necessary but not sufficient condition for justice)4. The stricter of the safe or just boundaries sets the integrated safe and just ESB. Our findings show that justice considerations constrain the integrated ESBs more than safety considerations for climate and atmospheric aerosol loading. Seven of eight globally quantified safe and just ESBs and at least two regional safe and just ESBs in over half of global land area are already exceeded. We propose that our assessment provides a quantitative foundation for safeguarding the global commons for all people now and into the future