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Potato early blight is caused by the necrotrophic fungus Alternaria solani and can result in yield losses of up to 50% if left uncontrolled. At present, the disease is controlled by chemical fungicides, yet rapid development of fungicide resistance renders current control strategies unsustainable. On top of that, a lack of understanding of potato defences and the quantitative nature of resistance mechanisms against early blight hinders the development of more sustainable control methods. Necrotrophic pathogens, compared to biotrophs, pose an extra challenge to the plant, since common defence strategies to biotic stresses such as the hypersensitive response and programmed cell death are often beneficial for necrotrophs. With the aim of unravelling plant responses to both the early infection stages (i.e., before necrosis), such as appressorium formation and penetration, as well as to later responses to the onset of necrosis, we present here a transcriptome analysis of potato interactions with A. solani from 1 h after inoculation when the conidia have just commenced germination, to 48 h post inoculation when multiple cell necrosis has begun. Potato transcripts with putative functions related to biotic stress tolerance and defence against pathogens were upregulated, including a putative Nudix hydrolase that may play a role in defence against oxidative stress. A. solani transcripts encoding putative pathogenicity factors, such as cell wall degrading enzymes and metabolic processes that may be important for infection. We therefore identified the differential expression of several potato and A. solani transcripts that present a group of valuable candidates for further studies into their roles in immunity or disease development.

Adding functional electronic components to graphene nanoribbons requires precise control over their atomic structure. Here, the authors use a bottom-up approach to build a metal-semiconductor junction and a tunnel barrier directly into a single graphene nanoribbon, an exciting development for graphene-based electronic devices

Certain lattices with specific geometries have one or more spectral bands that are strictly flat, i.e., the electron energy is independent of the momentum. This can occur robustly irrespective of the specific couplings between the lattices sites due to the lattice symmetry, or it can result from fine-tuned couplings between the lattice sites. While the theoretical picture behind flat electronic bands is well developed, experimental realization of these lattices has proven challenging. Utilizing scanning tunneling microscopy (STM) and spectroscopy (STS), we manipulate individual vacancies in a chlorine monolayer on Cu(100) to construct various atomically precise one-dimensional (1D) lattices with engineered flat bands. We realize experimentally both gapped and gapless flat band systems with single or multiple flat bands. We also demonstrate tunability of the energy of the flat bands and how they can be switched on and off by breaking and restoring the symmetry of the lattice geometry. The experimental findings are corroborated by tight-binding calculations. Our results constitute the first experimental realizations of engineered flat bands in a 1D solid-state system and pave the way toward the construction of, e.g., topological flat band systems and experimental tests of flat-band-assisted superconductivity in a fully controlled system.

Early blight of potato, caused by Alternaria solani, is an economically important foliar disease in most potato-growing regions. Growing cultivars with higher levels of resistance to early blight can reduce tuber yield losses and the need for fungicide applications. In this research, a bi-parental tetraploid potato population, segregating for resistance to early blight in leaves and tubers, was characterized to identify novel quantitative trait loci (QTL) associated with foliar and tuber early blight resistance. Assessment of the disease resistance in the foliage was performed by field evaluation and in tuber under controlled conditions. Results from this study revealed significant differences (P < 0.001) in resistance to A. solani among potato clones both in the leaves and in tubers. There was no statistically significant correlation (r = 0.06, P = 0.35) between the resistance scores from leaves and tubers. Several clones exhibited; however, high levels of resistance both in leaves and tubers and are; thus, promising candidates for breeding for early blight resistance. Linkage mapping revealed several QTL for early blight affecting both foliage and tubers. QTL associated with disease resistance in the tuber were found on chromosomes 1, 2, 3, 4, 8, 11 and 12. QTL associated with disease resistance in foliage were also examined for independence from defoliation, and independent QTL were; thus, found on chromosomes 5 and 11.

The fabrication of atomically precise structures with designer electronic properties is one of the emerging topics in condensed matter physics. The required level of structural control can either be reached through atomic manipulation using the tip of a scanning tunnelling microscope (STM) or by bottom-up chemical synthesis. In this review, we focus on recent progress in constructing novel, atomically precise artificial materials: artificial lattices built through atom manipulation and graphene nanoribbons (GNRs) realized by on-surface synthesis. We summarize the required theoretical background and the latest experiments on artificial lattices, topological states in one-dimensional lattices, experiments on graphene nanoribbons and graphene nanoribbon heterostructures, and topological states in graphene nanoribbons. Finally, we conclude our review with an outlook to designer quantum materials with engineered electronic structure.

Background: The healthcare system has a growing need for knowledgeable and skilled health care personnel to meet the demands to support student learning in clinical training. One way to assess teachers' competence is to use a teacher portfolio; however, this has not been done with the mission of clinical health care personnel in focus. Therefore, the aim of this study was to develop a portfolio to assess clinical health care personnel´s pedagogical competence. Methods: Pedagogical active nurses and physicians from the anesthesia department, operating room and intensive care, and an educational expert with extensive experience of developmental work of pedagogical portfolios in the academic setting developed a qualifications portfolio for pedagogical competence in the clinical setting. Result: The assessment standards define five levels of teaching competence and include both experience and quality of the educational mission in the clinical setting. The pedagogical portfolio is congruent with the assessment tool and structured with headings to promote clinical teachers to document both quantitative and qualitative aspects of teaching. Conclusion: The portfolio enables clinicians and managers in academic hospitals to highlight the need for high-quality professional and the ability to identify needs for pedagogical skills among health care personnel.

Late blight (caused by Phytophthora infestans) is a devastating potato disease that has been found to occur earlier in the season over the last decades in Fennoscandia. Up until now the reasons for this change have not been investigated. Possible explanations for this change are climate alterations, changes in potato production or changes in pathogen biology, such as increased fitness or changes in gene flow within P. infestans populations. The first incidence of late blight is of high economic importance since fungicidal applications should be typically applied two weeks before the first signs of late blight and are repeated on average once a week.We use field observations of first incidence of late blight in experimental potato fields from five sites in Sweden and Finland covering a total of 30 years and investigate whether the earlier incidence of late blight can be related to the climate.We linked the field data to meteorological data and found that the previous assumption, used in common late blight models, that the disease only develops at relative humidity levels above 90% had to be rejected. Rather than the typically assumed threshold relationship between late blight disease development and relative humidity we found a linear relationship. Our model furthermore showed two distinct responses of late blight to climate. At the beginning of the observation time (in Sweden until the early 90s and in Finland until the 2000s) the link between climate and first incidence was very weak. However, for the remainder of the time period the link was highly significant, indicating a change in the biological properties of the pathogen which could for example be a change in the dominating reproduction mode or a physiological change in the response of the pathogen to climate.The study shows that models used in decision support systems need to be checked and re-parametrized regularly to be able to capture changes in pathogen biology. While this study was performed with data from Fennoscandia this new pathogen biology and late blight might spread to (or already be present at) other parts of the world as well. The strong link between climate and first incidence together with the presented model offers a tool to assess late blight incidence in future climates.