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Phonon-assisted tunneling through quantum dot stacks

The impact of electron-phonon interaction on the coherent transport through a quantum dot stack is investigated using the nonequilibrium Green's function technique. While the main resonance is due to the alignment of the single dot levels, satellite peaks occur due to resonances with phonon replica of the bare levels. This effect is analyzed in detail and we show that the inclusion of nondiagonal

Targeting type 1 diabetes before and at the clinical onset of disease.

Autoimmune type 1 diabetes is strongly associated with a number of immune abnormalities that manifest themselves before and at the time of clinical diagnosis. The clinical onset is associated with a major loss of the pancreatic islet beta cells. Insulin treatment is the only treatment option since numerous trials with agents that suppress or modulate immune function have failed to preserve beta ce

Infrared photodetectors in heterostructure nanowires

We report on spectrally resolved photocurrent measurements on single self-assembled nanowire heterostructures. The wires, typically 3 mu m long with an average diameter of 85 nm, consist of InAs with a 1 mu m central part of InAsP. Two different sets of wires were prepared with phosphorus contents of 15 +/- 3% and 35 +/- 3%, respectively, as determined by energy-dispersive spectroscopy measurement

Determination of the detection limit of Ni-59 at the Lund AMS facility by using characteristic projectile X-rays

Accelerator mass spectrometry (AMS) is an ultra-sensitive method for counting atoms, both radionuclides and stable nuclides. When using small tandem accelerators to measure heavy isotopes, interfering isobars are often troublesome. One way to reduce this interference is to combine AMS with the detection of characteristic X-rays of the projectile. After analysis in the AMS system it is possible to

Observation of superdeformed states in Mo-88

High-spin states in Mo-88 were studied using the GAMMASPHERE germanium detector array in conjunction with the MICROBALL CsI(TI) charged-particle detector system. Three gamma-ray cascades with dynamic moments of inertia showing similar characteristics to superdeformed rotational bands observed in the neighbouring A = 80 region have been identified and assigned to the nucleus Mo-88. The quadrupole m

Presence of mouse mammary tumour-like virus gene sequences may be associated with morphology of specific human breast cancer

BACKGROUND: Mouse mammary tumour virus (MMTV) has a proven role in breast carcinogenesis in wild mice and genetically susceptible in-bred mice. MMTV-like env gene sequences, which indicate the presence of a replication-competent MMTV-like virus, have been identified in some human breast cancers, but rarely in normal breast tissues. However, no evidence for a causal role of an MMTV-like virus in hu

In vitro metabolism and in vivo pharmacokinetics of quinoline 3-carboxamide derivatives in various species

The metabolism of a group of quinoline 3-carboxamide derivatives was evaluated in liver microsomes from various species. In addition, metabolism data were compared with in vivo pharmacokinetics in the mouse. The studied compounds were metabolized by cytochrome P450 enzymes. Microsomal clearance was low and seemed independent of a substituent in the quinoline moiety, whereas clearance was enhanced

Isospin effects in two-particle correlation functions: A probe for the isospin dependence of the nuclear equation of state

Small-angle two-particle correlation functions, involving neutrons and protons, have been measured for E/A = 61 MeV Ar + Sn-112,Sn-124 collisions, i.e. systems similar in size but with different isospin asymmetry. The correlation strength of neutron-proton (np) and proton-proton (pp) pairs is stronger for the more neutron-rich system, indicating a shorter average emission time for this system. Com

Hepatitis C virus infection with progression to hepatocellular carcinoma: a report of five prospectively followed patients in Sweden

Five Swedish patients with chronic hepatitis C were prospectively followed until hepatocellular carcinoma (HCC) developed. Hepatitis C virus (HCV) antibodies were analysed by a second generation anti-HCV ELISA and a recombinant immunoblot assay (RIBA-2) and viraemia by detection of serum HCV RNA by polymerase chain reaction. Four patients had post transfusion hepatitis and in one patient the sourc

A didodecyldimethylammonium bromide ternary system: Characterization of three-phase stable emulsions by optical microscopy

A preliminary characterization of the didodecyldimethyl ammonium bromide (DDAB)/water (W)/per fluorooctane (PFO) ternary system at 25 degreesC is presented. The gradual addition of water, followed by mixing, to DDAB/PFO mixtures produces very stable emulsions for water contents greater than 20 wt%. On the basis of macroscopic observation, at least four different types of emulsions form up to a wat

A new circumscription of the lichen genus Nephromopsis (Parmeliaceae, lichenized Ascomycetes).

The phylogeny of the cetrarioid lichens with bifusiform spermatia and dorsiventral thalli which contain usnic acid is reanalysed using three parts of the genome, ITS rDNA, b-tubulin and GAPDH sequences. Molecular data from five cetrarioid species are presented for the first time, and 13 new sequences are combined with sequences from the gene bank to delimit the genus Nephromopsis. A monophyletic c

Main targets of tetraaza macrocyclic copper complex on L1210 murine leukemia cells

Several metal complex agents have already been introduced into clinical tumor therapy and others are subject of antitumor studies. In this study we focused on the tetraaza macrocyclic copper complex (Cu(TAAB)Cl-2). We studied the influence of the substance on cell growth, cell cycle, membrane integrity, necrosis, apotosis and glutathione level on the leukemic cell line L1210 in 1-day (22 h) and 3-

Cancer risk after hospital discharge diagnosis of benign ovarian cysts and endometriosis.

Background. The aim was to evaluate whether patients with benign ovarian cysts, functional ovarian cysts, or endometriosis have an increased risk of developing gynecologic cancer. Methods. The Swedish Hospital Discharge Register was used to identify a cohort of women discharged from hospital with the diagnoses of ovarian cyst (n = 42 217), functional ovarian cyst (n = 17 998), or endometriosis (n