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Continuous variable entanglement can be produced in nonlinear systems or via interference of squeezed states. In many of optical systems, such as parametric down conversion or interference of optical squeezed states, production of two perfectly symmetric subsystems is usually used for demonstrating the existence of entanglement. This symmetry simplifies the description of the concept of entanglement. However, asymmetry in entanglement may arise naturally in a real experiment, or be intentionally introduced in a given quantum information protocol. These asymmetries can emerge from having the output beams experience different losses and environmental contamination, or from the availability of non-identical input quantum states in quantum communication protocols. In this paper, we present a visualisation of entanglement using quadrature amplitude plots of the twin beams. We quantitatively discuss the strength of asymmetric entanglement using EPR and inseparability criteria and theoretically show that the optimal beamsplitter ratio for entanglement is dependent on the asymmetries and may not be 50/50. To support this theory, we present experimental results showing one particular asymmetric entanglement where a 0.78/0.22 beamsplitter is optimal for observing entanglement., Comment: 11 pages, 14 figures

Quantum protocols require multiple entangled modes. We demonstrate a set of tools that generate, manipulate and detect multimode entanglement within a single beam of light. This new method is flexible and computer controlled.

We experimentally demonstrate the generation of optical squeezing at multiple longitudinal modes and transverse Hermite-Gauss modes of an optical parametric amplifier. We present measurements of approximately 3 dB squeezing at baseband, 1.7 GHz, 3.4 GHz and 5.1 GHz which correspond to the first, second and third resonances of the amplifier. We show that both the magnitude and the bandwidth of the squeezing at the higher longitudinal modes is greater than can be observed at baseband. The squeezing observed is the highest frequency squeezing reported to date.

We combine experimental improvements to present an in principle demonstration of the use of multiple co propagating modes for quantum protocols.

Position and momentum were the first pair of conjugate observables explicitly used to illustrate the intricacy of quantum mechanics. We have extended position and momentum entanglement to bright optical beams. Applications in optical metrology and interferometry require the continuous measurement of laser beams, with the accuracy fundamentally limited by the uncertainty principle. Techniques based on spatial entanglement of the beams could overcome this limit, and high-quality entanglement is required. We report a value of 0.51 for inseparability and 0.62 for the Einstein-Podolsky-Rosen criterion, both normalized to a classical limit of 1. These results are a conclusive optical demonstration of macroscopic position and momentum quantum entanglement and also confirm that the resources for spatial multimode protocols are available.

The latest results on the experimental generation of the position and momentum (x-p) entanglement for bright optical beams are presented. The measurements of the quantum correlations in the TEM10 mode with two optical parametric amplifiers are demonstrated. TEM10 quadrature entanglement is also demonstrated. Two position squeezed beams on a 50:50 beam splitter are used to demonstrate full x-p entanglement.

We present the key elements required for continuous variable parallel quantum information protocols based on spatial multimode quantum correlations. We describe techniques for encoding, combining and detecting spatial quantum information with high efficiency in the individual transverse modes. Until now, the missing feature for the implementation of such protocols was the generation of squeezing in higher order transverse Hermite-Gauss modes. We experimentally demonstrate squeezing in selective modes by fine-tuning the phase matching condition of the nonlinear ${\ensuremath{\chi}}^{(2)}$ material and the cavity resonance condition of an optical parametric amplifier. Combined, these results open the way to practical multimode optical quantum information systems.

The spatial properties of laser beams can be used to encode, transfer and detect quantum information into high order modes with high efficiency. We demonstrate the use of such states, including spatial squeezing and entanglement.

Streptococcus parasanguis is a primary colonizer of dental plaque and a major player in subacute bacterial endocarditis. In the present study, the authors report that an ORF (ORF3) located 77 bp downstream of the fimA operon on the S. parasanguis FW213 chromosome complements an Escherichia coli thiol peroxidase (tpx) mutation in glutamine synthetase (GS) protection assays and that GS is protected by the ORF3 gene product in S. parasanguis cell extracts. In addition, the putative streptococcal peroxidase (Tpx(Sp)) protects S. parasanguis from stress caused by H2O2 and is induced by oxygen, as revealed by Northern blot analysis. Taken collectively, these findings support a thiol-dependent antioxidant activity for Tpx in S. parasanguis.

Background: Minority women and women with low income levels are significantly less likely to practice appropriate mammography and Pap test screening. ENCOREplus is a health promotion program that provides outreach, education, referral, and other services that facilitate breast and cervical cancer screening for medically underserved women. The program is delivered through a network of community-based nonprofit organizations (YWCA of the U.S.A.). The purpose of this study was to assess the effectiveness of ENCOREplus in promoting mammography and Pap test screening among women who were nonadherent to screening guidelines. Methods: Baseline data were collected from women participating in the program. Follow-up occurred within six months of baseline to assess whether or not enrollees received recommended screenings. Screening-completion rates were compared to rates from other published intervention studies. Results: Data from the program’s second implementation year show that 27,494 women participated in the ENCOREplus program. Over half the women were racial/ethnic minorities, over 75% reported annual incomes under $15,000, and 49% reported no insurance. Among women 40 and over, 69.7% were nonadherent to ACS mammography screening guidelines at baseline. Among participants 18 and older, 68.9% were nonadherent to Pap test screening guidelines. Of nonadherent participants, 57.8% received mammograms and 36.5% received Pap tests. Both mammography and Pap test screening-completion rates compared favorably with other programs. Conclusion: This study demonstrates that programs implemented through community-based organizations can be successful in increasing mammography and Pap test screening among low-income and minority women.

This paper describes work done by MSB Technology Applications, Inc. in identifying and evaluating airseparation or air-enrichment technologies for application to on-board hypersonic flight vehicles. The research was funded by the National Aeronautics and Space Administration (NASA). Successful technologies must meet requirements for in-flight production of highly oxygen-enriched air. As expected for components of flight vehicles, these systems must meet very stringent weight, volume, and reliability requirements. The initial scope of that project element was to screen air-separation technologies in accordance with a prescribed set of performance requirements and select the most promising for further evaluation. That task was completed and is reported in this paper with the results and recommendations of that analysis. This paper also presents the current status of the study of the potential of each technology and/or combination for hypersonic application. The critical issues and recommendations are also discussed.

A method for continuous intravenous infusion of unanesthetized adult C3H/HeJ or Wx/Wv anemic mice was designed using cage immobilization and a tail vein catheter connected to a model 940 Harvard infusion pump. Infusates included: WEHI-3 cell line dialyzed, 5 times concentrated conditioned medium containing multi-colony-stimulating factor (C-SF) interleukin 3 (IL-3); purified murine IL-3; bacterial endotoxin; serum-free medium, or normal saline. Mice were monitored at days 5-7 after infusion for complete peripheral blood counts and production of granulocytes in vitro by explanted marrow in long-term bone marrow cultures. We observed a stimulatory effect of WEHI-3 conditioned medium infusion that was not attributable to endotoxin and produced significant increases in peripheral blood WBC count and neutrophils, colony-forming units in spleen and numbers of granulocyte/macrophage colony-forming unit culture responsive to both C-SF-1 (L cell C-SF) and multi-C-SF in vitro. This infusion method should prove valuable for test of the in vivo effects of purified growth factors and molecularly cloned hematopoietins.

The adherent stromal layer in long-term bone marrow cultures (LTBMC) provides the cellular environment necessary for the in vitro proliferation and differentiation of pluripotential hematopoietic stem cells. The role of humoral hematopoietic growth factors, colony-stimulating factors (CSF) in the regulation of hematopoietic cell production in this system is poorly understood. We have recently isolated and cloned an adherent cell line, D2XRII, derived from murine LTBMC. Plateau phase 25 cm2 cultures of 2 X 10(6) D2XRII cells in 8.0 ml produced CSF-1 (M-CSF) at around 100-150 units/0.1 ml medium. Following X-irradiation there was a dose-dependent decrease in the production of CSF-1 to a plateau of 50% of control levels at 10,000 rad. Higher doses did not produce a further decrease. The X-ray dose reducing CSF-1 production to 50% was 100-fold above the lethal dose as measured by clonagenic survival following trypsinization and replating. Trypsinized replated viable adherent but nondividing X-irradiated D2XRII cells were maintained for up to 8 weeks after irradiation and demonstrated continuous production of CSF-1. The data indicate significant divergence of two biologic effects of X-irradiation on plateau-phase marrow stromal cells: physiologic function of adherence and CSF-1 production, versus proliferative integrity. This divergence of effects may be very relevant to understanding the mechanism of X-irradiation-associated marrow suppression and leukemogenesis.

We studied the production of hemopoietins by x-irradiated plateau-phase cultures of cloned marrow stromal cell lines derived from C3H/HeJ marrow, termed D2XRII and clone 11. The production of CSF in agar overlay of control or 10,000 rad irradiated stromal cultures was quantitated by induction of colonies in: overlaid fresh marrow, IL-3- dependent cell line 32D cl 3, or GM-CSF/IL-3-dependent cell lines FDCP- 1 or bg/bg cl 1. Conditioned media were tested for CSF by bioassay using fresh marrow cells, for M-CSF (CSF-1) by RIA, and for IL-3 and GM- CSF by microwell proliferation assay with 32D cl 3 and FDCP-1 cells, respectively. X-irradiation to doses that decreased CSF-1 to 40% of control levels (greater than 5,000 rad) resulted in a 30-fold increase in growth of FDCP-1 or bg/bg cl 1 cells in liquid co-culture or agar culture overlay with no detectable growth of 32D cl 3. The frequency of subculture of nonautocrine, factor independent (FI) variant clonal lines of FDCP-1 or bg/bg cl 1 cells was increased over 1000-fold by 15 weeks cocultivation with irradiated stromal cell cultures. FI subclonal lines formed tumors in syngeneic mice and contained no detectable poly A messenger RNA for GM-CSF or IL-3, and no elevation in c-myc, c-abl, c- src, or erb-B onc gene-specific messenger RNA compared to parent factor- dependent lines. These data indicate that x-irradiated plateau phase marrow stromal cells produce increased levels of cell contact-mediated biologically active hemopoietin(s) other than M-CSF, GM-CSF, or IL-3 and induce nonautocrine factor-independent malignant cell lines in vitro.

A small subset of leukemic cells from most patients with acute myeloblastic leukemia (AML) have properties of stem cells and can be assayed by colony formation in agar or methylcellulose. Colony formation generally requires the addition of exogenous growth factors, but the exact factors required are incompletely defined. The AML colony- promoting activities of two recombinant human colony-stimulating factors (GM-CSF and G-CSF) were investigated by using blasts from 48 patients with AML. In nine cases, no colonies formed with either CSF. In seven cases colonies formed only in response to G-CSF and in 11 cases only in response to GM-CSF. In 21 cases colonies formed in response to either GM-CSF or G-CSF, and in 12 of these cases there was an additive effect between the two CSFs in determining maximum colony size. For cases responding to both GM- and G-CSF, the total number of colonies formed in response to the combination of both CSFs was almost always less than additive compared with the number of colonies formed in response to the individual CSFs. Further, the AML-CFU responding to either GM-CSF or G-CSF could not be distinguished by surface markers or by the cytochemical staining pattern of the colonies. These results suggest that there is considerable overlap between the GM-CSF- and G- CSF-responsive AML-CFU subpopulations in most cases. For five of seven cases, the combination of GM-CSF and G-CSF could replace a leukocyte feeder layer in providing maximum growth stimulation. These results indicate that GM-CSF and G-CSF are active growth factors for AML cells and are frequently additive in promoting maximum colony size.

We present the latest results on the experimental generation of the position and momentum (x-p) entanglement for bright optical beams [1]. Spatial entanglement of light is a direct demonstration of entanglement of the momentum and position of laser beam as envisioned in the original publication by Einstein, Podolsky and Rosen [2]. Spatial entanglement has potential applications in quantum imaging systems and for quantum communication protocols. The position-momentum entanglement was observed in the form of the degree of inseparability, which was measured to be no larger than 0.76.

The spatial properties of laser beams can be used to encode, transfer and detect quantum information into high order modes with high efficiency. We demonstrate the use of multimode states, including spatial squeezing and entanglement