Relational interpretation of the wave function and a possible way around Bell's theorem

The famous ``spooky action at a distance'' in the EPR-szenario is shown to be a local interaction, once entanglement is interpreted as a kind of ``nearest neighbor'' relation among quantum systems. Furthermore, the wave function itself is interpreted as encoding the ``nearest neighbor'' relations between a quantum system and spatial points. This interpretation becomes natural, if we view space and distance in terms of relations among spatial points. Therefore, ``position'' becomes a purely relational concept. This relational picture leads to a new perspective onto the quantum mechanical formalism, where many of the ``weird'' aspects, like the particle-wave duality, the non-locality of entanglement, or the ``mystery'' of the double-slit experiment, disappear. Furthermore, this picture cirumvents the restrictions set by Bell's inequalities, i.e., a possible (realistic) hidden variable theory based on these concepts can be local and at the same time reproduce the results of quantum mechanics.Comment: Accepted for publication in "International Journal of Theoretical Physics

On Multiparticle Entanglement via Resonant Interaction between Light and atomic Ensembles

Multiparticle entangled states generated via interaction between narrow-band light and an ensemble of identical two-level atoms are considered. Depending on the initial photon statistics, correlation between atoms and photons can give rise to entangled states of these systems. It is found that the state of any pair of atoms interacting with weak single-mode squeezed light is inseparable and robust against decay. Optical schemes for preparing entangled states of atomic ensembles by projective measurement are described.Comment: 11 pages, 1 figure, revtex

Acquisition of Ca2+ and HCO3−/CO32− for shell formation in embryos of the common pond snail Lymnaea stagnalis

Embryos of the freshwater common pond snail Lymnaea stagnalis develop to hatch within 10 days under control conditions (22°C, Miami-Dade tap water) and this development is impaired by removal of ambient calcium. In contrast, embryos did not exhibit dependence upon an ambient HCO3−/CO32− source, developing and hatching in HCO3−/CO32−-free water at rates comparable to controls. Post-metamorphic, shell-laying embryos exhibited a significant saturation-type calcium uptake as a function of increasing ambient calcium concentration. However, changes in ambient bicarbonate concentration did not influence calcium or apparent titratable alkalinity uptake. There was a distinct shift from no significant flux in pre-metamorphic embryos to net uptake of calcium in post-metamorphic stages as indicated by an increased uptake from the micro-environment surrounding the egg mass and increased net uptake in 24-h, whole egg mass flux measurements. Furthermore, HCO3−/CO32− acquisition as measured by titratable alkalinity flux is at least partially attributable to an endogenous carbonate source that is associated with acid extrusion. Thus, calcium requirements for embryonic shell formation are met via uptake but HCO3−/CO32−, which is also necessary for shell formation is acquired in part from endogenous sources with no detectable correlation to ambient HCO3−/CO32− availability

A Comprehensive Classification and Evolutionary Analysis of Plant Homeobox Genes

The full complement of homeobox transcription factor sequences, including genes and pseudogenes, was determined from the analysis of 10 complete genomes from flowering plants, moss, Selaginella, unicellular green algae, and red algae. Our exhaustive genome-wide searches resulted in the discovery in each class of a greater number of homeobox genes than previously reported. All homeobox genes can be unambiguously classified by sequence evolutionary analysis into 14 distinct classes also characterized by conserved intron–exon structure and by unique codomain architectures. We identified many new genes belonging to previously defined classes (HD-ZIP I to IV, BEL, KNOX, PLINC, WOX). Other newly identified genes allowed us to characterize PHD, DDT, NDX, and LD genes as members of four new evolutionary classes and to define two additional classes, which we named SAWADEE and PINTOX. Our comprehensive analysis allowed us to identify several newly characterized conserved motifs, including novel zinc finger motifs in SAWADEE and DDT. Members of the BEL and KNOX classes were found in Chlorobionta (green plants) and in Rhodophyta. We found representatives of the DDT, WOX, and PINTOX classes only in green plants, including unicellular green algae, moss, and vascular plants. All 14 homeobox gene classes were represented in flowering plants, Selaginella, and moss, suggesting that they had already differentiated in the last common ancestor of moss and vascular plants

Expression of endothelia and lymphocyte adhesion molecules in bronchus-associated lymphoid tissue (BALT) in adult human lung

BACKGROUND: Bronchus-associated lymphoid tissue (BALT) is the secondary lymphoid tissue in bronchial mucosa and is involved in the development of bronchopulmonary immune responses. Although migration of lymphocytes from blood vessels into secondary lymphoid tissues is critical for the development of appropriate adaptive immunity, the endothelia and lymphocyte adhesion molecules that recruit specific subsets of lymphocytes into human BALT are not known. The aim of this study was to determine which adhesion molecules are expressed on lymphocytes and high endothelial venules (HEVs) in human BALT. METHODS: We immunostained frozen sections of BALT from lobectomy specimens from 17 patients with lung carcinoma with a panel of monoclonal antibodies to endothelia and lymphocyte adhesion molecules. RESULTS: Sections of BALT showed B cell follicles surrounded by T cells. Most BALT CD4+ T cells had a CD45RO+ memory phenotype. Almost all BALT B cells expressed alpha4 integrin and L-selectin. In contrast, 43% of BALT T cells expressed alpha4 integrin and 20% of BALT T cells expressed L-selectin. Almost all BALT lymphocytes expressed LFA-1. HEVs, which support the migration of lymphocytes from the bloodstream into secondary lymphoid tissues, were prominent in BALT. All HEVs expressed peripheral node addressin, most HEVs expressed vascular cell adhesion molecule-1, and no HEVs expressed mucosal addressin cell adhesion molecule-1. CONCLUSION: Human BALT expresses endothelia and lymphocyte adhesion molecules that may be important in recruiting naive and memory/effector lymphocytes to BALT during protective and pathologic bronchopulmonary immune responses

A role for pharmacists in community-based post-discharge warfarin management: protocol for the 'the role of community pharmacy in post hospital management of patients initiated on warfarin' study

<p>Abstract</p> <p>Background</p> <p>Shorter periods of hospitalisation and increasing warfarin use have placed stress on community-based healthcare services to care for patients taking warfarin after hospital discharge, a high-risk period for these patients. A previous randomised controlled trial demonstrated that a post-discharge service of 4 home visits and point-of-care (POC) International Normalised Ratio (INR) testing by a trained pharmacist improved patients' outcomes. The current study aims to modify this previously trialled service model to implement and then evaluate a sustainable program to enable the smooth transition of patients taking warfarin from the hospital to community setting.</p> <p>Methods/Design</p> <p>The service will be trialled in 8 sites across 3 Australian states using a prospective, controlled cohort study design. Patients discharged from hospital taking warfarin will receive 2 or 3 home visits by a trained 'home medicines review (HMR)-accredited' pharmacist in their 8 to 10 days after hospital discharge. Visits will involve a HMR, comprehensive warfarin education, and POC INR monitoring in collaboration with patients' general practitioners (GPs) and community pharmacists. Patient outcomes will be compared to those in a control, or 'usual care', group. The primary outcome measure will be the proportion of patients experiencing a major bleeding event in the 90 days after discharge. Secondary outcome measures will include combined major bleeding and thromboembolic events, death, cessation of warfarin therapy, INR control at 8 days post-discharge and unplanned hospital readmissions from any cause. Stakeholder satisfaction will be assessed using structured postal questionnaire mailed to patients, GPs, community pharmacists and accredited pharmacists at the completion of their study involvement.</p> <p>Discussion</p> <p>This study design incorporates several aspects of prior interventions that have been demonstrated to improve warfarin management, including POC INR testing, warfarin education and home visits by trained pharmacists. It faces several potential challenges, including the tight timeframe for patient follow-up in the post-discharge period. Its strengths lie in a strong multidisciplinary team and the utilisation of existing healthcare frameworks. It is hoped that this study will provide the evidence to support the national roll-out of the program as a new Australian professional community pharmacy service.</p> <p>Trial Registration</p> <p>Australian New Zealand Clinical Trials Registry Number <a href="http://www.anzctr.org.au/trial_view.aspx?ID=82959">12608000334303</a>.</p

The fate of received sperm in the reproductive tract of a hermaphroditic snail and its implications for fertilisation.

Multiple mating, sperm storage and internal fertilisation enhance sperm competition. The great pond snail can use stored sperm for over three months, and frequently mates with different partners. This hermaphrodite, Lymnaea stagnalis, can also self-fertilise and often produces egg masses containing both selfed and outcrossed eggs. Hence, a sperm recipient may exert considerable control over paternity. Using microsatellite markers, we show that when allosperm are present, all genotyped eggs are cross-fertilised. We also find that sperm have the opportunity to compete, because double matings lead on average to equal paternity for each sperm donor. This indicates that received sperm are randomly mixed in storage. To gain further insight into the mechanisms underlying the process of sperm storage, digestion and utilisation, we investigated the fate of donated sperm at different times after copulation. We find that within 3 h after transfer most sperm have been transported into the sperm-digesting organ. Fluorescent labelling of sperm in histological sections further reveals that allosperm are not stored in the fertilisation pouch, but upstream in either the hermaphroditic duct, seminal vesicles, or ovotestis. Besides contributing to the understanding of the mechanisms underlying sperm competition and/or cryptic sperm choice, this study shows that mixed mating cannot be treated as a separate issue in hermaphroditic animals. © Springer Science+Business Media B.V. 2008