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A search for first generation excited neutrinos is performed using the full e(-) p data sample collected by the HI experiment at HERA at a centre-of-mass energy of 319 GeV, corresponding to a total luminosity of 184 pb(-1). The electroweak decays of excited neutrinos nu* -> nu gamma, v* -> nu Z and nu* -> eW with subsequent hadronic or leptonic decays of the W and Z bosons are considered. No evide

Seed particles of elements or compounds which may or may not form alloys are now used extensively in promoting well-controlled nanowire growth. The technology has evolved following the well-known Vapour-Liquid-Solid (VLS) model which was developed over 40 years ago. This model indicates that a liquid alloy is formed from the seed particle and the growth precursor(s), resulting in crystal growth by

The mystacocarid crustacean Derocheilocaris typica has two microvillar organs, one new, the other previously unappreciated in crustacean literature. The first is situated on the head-shield and consists of three pairs of cells: one with microvilli and a ballooned nucleus; one smaller and without special features; the third large and investing the other two and extending down to the foregut. We cal

Brain machine interfaces with chronically implanted microelectrode arrays for signal acquisition require algorithms for successful detection and classification of neural spikes. During the design of such algorithms, signals with a priori known characteristics need to be present. A common way to establish such signals is to model the recording environment, simulate the recordings and store ground t

Domestication processes tend to release animals from natural selection and favour traits desired by humans, such as food-production and co-operative behaviour. A side effect of such selective breeding is the alteration of unintended traits. In this paper, we investigate how active selection for egg production in chickens has affected the visual system, in particular the optical sensitivity that re

Calcitonin gene-related peptide (CGRP) research was initiated by Poyner et al.,(1) who found that the calcitonin gene encodes the 37-amino acid neuropeptide CGRP in neuronal tissue. Within months, the Lund group produced antibodies toward α-CGRP and developed sensitive methods to study the role of this peptide in the cranial circulation. Intracranial vessels and the trigeminal ganglion harbor this

Aortic arch repair, is a surgical challenge irrespective of which technique is applied. While open surgical repair is a major trauma and a technically difficult procedure that many elderly patients tolerate poorly, the branched and fenestrated stentgrafts remain complex to implant safely. Hybrid procedures combine some of the advantages of both open and endovascular techniques but also many disadv

Popular Abstract in Swedish Diabetes, i alla dess olika former, är en allvarlig sjukdom. Typ 1 diabetes är av autoimmun härkomst, då kroppen eget immunförsvaret attackerar och förstör β-cellerna i bukspottkörteln. Dessa celler producerar insulin som hjälper kolhydraterna i maten vi äter att komma kroppens celler till godo. Sverige har världens näst högsta antal nya insjuknanden, bara Finland har fThe role of miRNAs in pancreatic islets and β-cell function and in the development of diabetes in human and rodents have been investigated in this thesis. Dicer1 was specifically deleted in vivo in pancreatic β-cells under the RIP-promoter in mice. The results show that disruption of miRNAprocessing in mouse pancreatic β-cells, while compatible with β-cell development, leads to defective insulin-s