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ABC-stacked multilayer graphene (ABC-MLG) exhibits topological surface flat bands with a divergent density of states, leading to many-body instabilities at charge neutrality. Here, we explore electronic ordering within a mean-field approach with full generic treatment of all spin-isotropic, two-site charge density and spin interactions up to next-nearest-neighbor (NNN) sites. We find that surface

We used the paradigmatic GATA-PU.1 axis to explore, at the systems level, dynamic relationships between transcription factor (TF) binding and global gene expression programs as multipotent cells differentiate. We combined global ChIP-seq of GATA1, GATA2, and PU.1 with expression profiling during differentiation to erythroid and neutrophil lineages. Our analysis reveals (1) differential complexity

We explore cell heterogeneity during spontaneous and transcription-factor-driven commitment for network inference in hematopoiesis. Since individual genes display discrete OFF states or a distribution of ON levels, we compute and combine pairwise gene associations from binary and continuous components of gene expression in single cells. Ddit3 emerges as a regulatory node with positive linkage to e

I dagens samhälle har maskininlärning en betydande roll, speciellt den delen som kallas för artificiella neuronnät (ANN). Dessa är användbara algoritmer som vagt härmar hur våra biologiska nätverk fungerar. De har visat sig vara skickliga i att lära sig klassificera, och generellt lära sig kopplingar mellan indata och utdata. ANN används flitigt för informationshantering av jättar som Facebook, YoArtificial Neural Networks (ANNs) are widely used information processing algorithms based roughly on biological neural networks. These networks can be trained to find complex patterns in datasets and to produce certain output signals given a set of input signals. A key element of ANNs are their so-called activation functions, which control the signal strengths between the artificial neurons in a n

Artificiella neuronnät är en mer och mer populär del av maskininlärning. Nätverken byggs upp av sammankopplade noder, där varje nod är en simpel matematisk modell av en neuron. Neuronnät kan användas för att lösa olika problem, t.ex. överlevnadsanalys inom medicin. Ett exempel på överlevnadsanalys är uppskattning av tiden innan ett återfall av cancer efter en tumör har tagits bort, baserat på t.eArtificial neural networks have been used to solve different problems, one being survival analysis of medical data. For survival analysis, the main interest is often how samples become sorted by their outputs, which makes survival analysis a rank based problem. A rank based error function lacks a gradient, which makes gradient descent based training difficult. A genetic training algorithm, based o

Intresset för att studera protoplanetära diskar har ökat inom forskarvärlden i och med de observationer av dem som har gjorts de senaste åren. Observatoriet Atacama Large Millimeter Array (ALMA) i Chile har observerat flertalet protoplanetära diskar i enastående detalj. Dessa observationer har motiverat forskare till ytterligare teoretiska studier av protoplanetära diskar och deras dynamiska utvecProtoplanetary discs surround young stars for the first few million years after their formation and they are the birthplaces of planetary systems. The thermal structure of the discs is regulated by their dust content and the opacity that it provides. The aim of this project is to investigate the effect grain growth has on the structure of the protoplanetary discs. Hydrodynamical simulations have b

Lunds Observatoriums Vakuum-Echelle Spektrograf (LOVES) är en spektrograf byggd för att studera ultraviolett ljus i våglängdsregionen 1000- 2000Å. Ultraviolett (UV) ljus i denna våglängdsregion absorberas i luft varför LOVES är konstruerad inuti en 2,5m lång evakuerad tank. LOVES är i dagsläget inte ett helt fullbordat vetenskapligt instrument. Detta projekthar haft som mål att utveckla och testa In this report we present the testing and development made using the Lund Observatory Vacuum Echelle Spectrograph (LOVES) during the last few years. Hardware development includes an assembly from base components due to relocation and necessary calibrations of the optics. Software devel- opment includes the making of a basic image processing pipeline for the instrument. The testing of LOVES wavelen

Heta Jupitrar är gasjättar som Jupiter vars omloppsbana för dem närmre sin värdstjärna än Merkurius bana kring Solen. Sen deras upptäckt har de visat sig vara väldigt viktiga i vår förståelse för exoplanet-atmosfärer. På Jorden minskar temperaturen av atmosfären med höjd över marken, förutom i ett område där temperaturen plötsligt går upp igen då ozonet som fångar UV-ljuset befinner sig på den höjContext. The discovery of hot Jupiters, giant gas exoplanets on tight orbits close to their host star, has proven instrumental in the study of exoplanet atmospheres through transit spectroscopy. Just as a temperature increase with height manifests in Earth’s atmosphere due to ozone absorbing ultraviolet radiation, transit spectra of some hot Jupiters has yielded evidence that suggests the presence

Gliomas are among the most aggressive malignant tumors and the most refractory to therapy, in part due to the propensity for malignant cells to disseminate diffusely throughout the brain. Here, we have used 27 K cDNA microarrays to investigate global gene expression changes between normal brain and high-grade glioma (glioblastoma multiforme) to try and better understand gliomagenesis and to identi

Background: There is a circadian and circaseptal (weekly) variation in the onset of acute coronary syndrome (ACS). The aim of this study was to elucidate whether the likelihood of ACS among emergency department (ED) chest pain patients varies with the time of presentation. Methods: All patients presenting to the Lund ED at Skåne University Hospital with chest pain or discomfort during 2006 and 20

Metabolites generated from fuel metabolism in pancreatic beta-cells control exocytosis of insulin, a process which fails in type 2 diabetes. To identify and quantify these metabolites, global and unbiased analysis of cellular metabolism is required. To this end, polar metabolites, extracted from the clonal 832/13 beta-cell line cultured at 2.8 and 16.7 mM glucose for 48 h, were derivatized followe

OBJECTIVE: The interface of a computerized decision support system is crucial for its acceptance among end users. We demonstrate how combined bar-line charts can be used to visualize predictions for individual patients from logistic regression models. STUDY DESIGN AND SETTING: Data from a previous diagnostic study aiming at predicting the immediate risk of acute coronary syndrome (ACS) among 634 p

The star, HD 207832, has two Jupiter-like planets on orbits with poorly constrained eccentricities. The eccentricities are 0.27 +0.22 -0.10 and 0.13$^{+0.18}_{-0.05}$ respectively. Notably, the two sigma error allows eccentricities up to 0.71 for one of the planets. Due to the large error bars, one aim of this project is to refine them. This is done by simulating the system for different initial e

Background Several models for prediction of acute coronary syndrome (ACS) among chest pain patients in the emergency department (ED) have been presented, but many models predict only the likelihood of acute myocardial infarction, or include a large number of variables, which make them less than optimal for implementation at a busy ED. We report here a simple statistical model for ACS prediction th