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We analyze symmetries of spin transport in two-terminal quantum waveguide structures with Rashba spin-orbit coupling and magnetic field modulations. Constraints, imposed by the device structure, on the spin polarization of the transmitted electron beam from the waveguide devices are derived. The results are expected to provide accuracy tests for experimental measurements and numerical calculations

Modern electronic medical implants have reached a high degree of complexity. This has increased the demands on the communication link with the implant, both regarding the bandwidth and the communication distance. A medical communication system at RF frequencies has been standardised, the Medical Implant Communication System (MICS), which use a frequency allocation of 402 - 405 MHz. This frequency

Many bird species demonstrate a variable mating system, with some males being monogamously mated and other males able to attract more than one mate. This variation in avian mating systems is often explained in terms of potential costs of sharing breeding partners and compensation for such costs. However, whenever there is a difference in the optimal mating system for males and females, a sexual co

Antagonism of voltage-dependent K+ (Kv) currents in pancreatic {beta}-cells may contribute to the ability of glucagon-like peptide-1 (GLP-1) to stimulate insulin secretion. The mechanism and signaling pathway regulating these currents in rat {beta}-cells were investigated using the GLP-1 receptor agonist exendin 4. Inhibition of Kv currents resulted from a 20-mV leftward shift in the voltage depen

Abstract in UndeterminedEmpirical results show that frequently the meaning of expressions used by students in expressing their understanding of subject matter does not correspond to the meaning of those expressions in the subject matter theory that the students are expected to learn. There is also often a lack of identity of meaning between the same students' use of the same expression from one us

The story I shall recount started in 1969, when I was given the opportunity to join the Department of Clinical Chemistry at the University Hospital in Malmo. I had just finished medical school at the university in the neighboring town of Lund. Parallel to pursuing my medical studies I had spent some time in the Department of Biochemistry. I did not know much about biochemistry, but it was enough f

Here, we investigated the effect of calpain inhibitors on apoptosis in organotypic adult spinal cord slices from mice. An increase in calpain I immunoreactivity was found in the nuclei of motor neurons from slices cultured for 30 min. After 4 h, the immunopositive motor neurons exhibited apoptotic changes including nuclear and chromatin condensation. Eight hours after excision, most motor neurons

The evaluation of chondroid lesions requires full integration of clinical, radiographic, and pathological data; tumour typing is often a challenge for the diagnostic pathologist. Although a variety of chromosomal abnormalities have been documented in chondroid lesions, the potential usefulness of cytogenetic analysis remains unclear. This study has critically reviewed and analysed 117 karyotyped s

We present a simple black box that takes a priority queue Q which supports find-min, insert, and delete in x-time at most t. Here x-time may be worst-case, expected, or amortized. The black-box transforms Q into a priority queue Q* that supports find-min in constant time, insert in constant x-time, and delete in x-time O(t). Moreover, if Q supports dec-key in constant time, then so does Q*.

Neural stem cells may present an ideal route for gene therapy as well as offer new possibilities for the replacement of neurons lost to injury or disease. However, it has proved difficult to express ectopic genes in stem cells. We report methods to introduce genes into adult neural stem cells using viral and nonviral vectors in vitro and in vivo. Adenoviral and VSV-G-pseudotyped retroviral vectors

Emission source functions are extracted from correlation functions constructed from charged pions produced at midrapidity in Au+Au collisions at s(NN)=200 GeV. The source parameters extracted from these functions at low k(T) give first indications of a long tail for the pion emission source. The source extension cannot be explained solely by simple kinematic considerations. The possible role of a

We present the first systematic investigation of shifts in the nuclear magnetic resonance (NMR) shielding constant due to hydrogen bonding using either the series of wave function based methods, Hartree-Fock (HF), second-order Moller-Plesset perturbation theory (MP2), Coupled Cluster Singles and Doubles (CCSD) and CCSD extended with an approximate description of triples (CCSD(T)), or Density Funct

Some patients with colonic diverticula suffer recurrent abdominal pain and exhibit visceral hypersensitivity, though the mechanism is unclear. Prior diverticulitis increases the risk of being symptomatic while experimental colitis in animals increases expression of neuropeptides within the enteric nervous system (ENS) which may mediate visceral hypersensitivity. Our aim was to determine the expres

Since the cloning in 1990 of complementary DNA corresponding to messenger RNA transcribed at the blood group ABO locus, polymorphisms and phenotype-genotype correlations have been reported by several investigators. Exons 6 and 7, constituting 77% of the gene, have been analyzed previously in samples with variant phenotypes but for many subgroups the molecular basis remains unknown. This study anal

With the objective to correlate clonogenicity, gene expression and phenotype during differentiation, human bone marrow CD34+ cells were cultured in vitro to stimulate erythroid or neutrophil development, and sorted into five subpopulations according to their surface expression of CD15/CD33 and blood group antigen A/CD117 respectively. Sorted cells were cultured in methylcellulose and analysed by r

The chronic active inflammation caused by Helicobacter pylori is dominated by neutrophils, macrophages, lymphocytes and plasma cells. Several interleukins are involved in the inflammatory process. The aim of this study was to investigate the effect of astaxanthin on gastric inflammation in patients with functional dyspepsia. Forty-four consecutive patients were included, and biopsies were examined

Background Cardiovascular autonomic dysfunction is associated with increased incidence of cardiovascular diseases (CVD). This population-based study explored whether low FEV(1) or low vital capacity (VC) is associated with autonomic dysfunction, as measured by the spontaneous heart rate variability (HRV) and systolic BP variability (SBPV). Methods SBPV and HRV were recorded during 5 min of control