226 research outputs found
Quantum entanglement distribution with 810 nm photons through telecom fibers
We demonstrate the distribution of polarization entangled photons of
wavelength 810 nm through standard telecom fibers. This technique allows
quantum communication protocols to be performed over established fiber
infrastructure, and makes use of the smaller and better performing setups
available around 800 nm, as compared to those which use telecom wavelengths
around 1550 nm. We examine the excitation and subsequent quenching of
higher-order spatial modes in telecom fibers up to 6 km in length, and perform
a distribution of high quality entanglement (visibility 95.6%). Finally, we
demonstrate quantum key distribution using entangled 810 nm photons over a 4.4
km long installed telecom fiber link.Comment: 5 pages, 5 figures, 1 tabl
Notes on the history of brackish water biology at the Universities of Rostock and Greifswald
On the occasion of the celebrations of the 50th year of existence of the biological station at Hiddensee (1982), the 150th jubilee year of the Zoological Institute of the Ernst-Moritz-Arndt-University in Greifswald (1986), and the 25th year of existence of an independent marine biological research and training facility at the University of Rostock (1985), a short overview is given of the development of biological science in the Baltic Sea in the Hither Pomerania and Mecklenburg region. It will become clear that the initiative for brackish water research arose at the University of Greifswald, with algological studies concentrated at Hiddensee and zoological-ecological work in Greifswald itself. Effective and successful marine biological research and teaching at the University of Rostock started with the establishment of the Department of Marine Biology (1960), where university marine biological activities are now concentrated as a result of the university reform (1968)
Successful Induction of Specific Immunological Tolerance by Combined Kidney and Hematopoietic Stem Cell Transplantation in HLA-Identical Siblings
Induction of immunological tolerance has been the holy grail of transplantation immunology for decades. The only successful approach to achieve it in patients has been a combined kidney and hematopoietic stem cell transplantation from an HLA-matched or -mismatched living donor. Here, we report the first three patients in Europe included in a clinical trial aiming at the induction of tolerance by mixed lymphohematopoietic chimerism after kidney transplantation. Two female and one male patient were transplanted with a kidney and peripherally mobilized hematopoietic stem cells from their HLA-identical sibling donor. The protocol followed previous studies at Stanford University: kidney transplantation was performed on day 0 including induction with anti-thymocyte globulin followed by conditioning with 10x 1.2 Gy total lymphoid irradiation and the transfusion of CD34+ cells together with a body weight-adjusted dose of donor T cells on day 11. Immunosuppression consisted of cyclosporine A and steroids for 10 days, cyclosporine A and mycophenolate mofetil for 1 month, and then cyclosporine A monotherapy with tapering over 9-20 months. The 3 patients have been off immunosuppression for 4 years, 19 months and 8 months, respectively. No rejection or graft-versus-host disease occurred. Hematological donor chimerism was stable in the first, but slowly declining in the other two patients. A molecular microscope analysis in patient 2 revealed the genetic profile of a normal kidney. No relevant infections were observed, and the quality of life in all three patients is excellent. During the SARS-CoV-2 pandemic, all three patients were vaccinated with the mRNA vaccine BNT162b2 (Comirnaty®), and they showed excellent humoral and in 2 out 3 patients also cellular SARS-CoV-2-specific immunity. Thus, combined kidney and hematopoietic stem cell transplantation is a feasible and successful approach to induce specific immunological tolerance in the setting of HLA-matched sibling living kidney donation while maintaining immune responsiveness to an mRNA vaccine (ClinicalTrials.gov: NCT00365846).
Keywords: COVID - 19; chimerism; hematopoietic stem cell transplantation (HSCT); immunocompetence; kidney transplantation; toleranc
Astrocytic Ion Dynamics: Implications for Potassium Buffering and Liquid Flow
We review modeling of astrocyte ion dynamics with a specific focus on the
implications of so-called spatial potassium buffering, where excess potassium
in the extracellular space (ECS) is transported away to prevent pathological
neural spiking. The recently introduced Kirchoff-Nernst-Planck (KNP) scheme for
modeling ion dynamics in astrocytes (and brain tissue in general) is outlined
and used to study such spatial buffering. We next describe how the ion dynamics
of astrocytes may regulate microscopic liquid flow by osmotic effects and how
such microscopic flow can be linked to whole-brain macroscopic flow. We thus
include the key elements in a putative multiscale theory with astrocytes
linking neural activity on a microscopic scale to macroscopic fluid flow.Comment: 27 pages, 7 figure
Observation of Positive-Parity Bands in Pd and Pd: Enhanced -Softness
The neutron-rich nuclei Pd and Pd were produced as fission
fragments following the Si + Er reaction at 142 MeV. Using the
identification based on the coincidences with the complementary fission
fragments, the only positive-parity bands observed so far in Pd and
Pd emerged from this work. A band, built on top of the 5/2 ground
state exhibiting = 1 energy-level staggering, was observed in each
of these nuclei. Both nuclei of interest, Pd and Pd, are
suggested to lie in the transitional region of Pd isotopes of maximum
-softness. The ground states of both nuclei are predicted by TRS
calculations to be extremely -soft with shallow triaxial minima. The
first crossing in the new bands is proposed to be due to an alignment of
neutrons
Sociodemographic factors associated with treatment-seeking and treatment receipt: cross-sectional analysis of UK Biobank participants with lifetime generalised anxiety or major depressive disorder
Background
Anxiety and depressive disorders can be chronic and disabling. Although there are effective treatments, only a fraction of those impaired receive treatment. Predictors of treatment-seeking and treatment receipt could be informative for initiatives aiming to tackle the burden of untreated anxiety and depression.
Aims
To investigate sociodemographic characteristics associated with treatment-seeking and treatment receipt.
Method
Two binary retrospective reports of lifetime treatment-seeking (n = 44 810) and treatment receipt (n = 37 346) were regressed on sociodemographic factors (age, gender, UK ethnic minority background, educational attainment, household income, neighbourhood deprivation and social isolation) and alternative coping strategies (self-medication with alcohol/drugs and self-help) in UK Biobank participants with lifetime generalised anxiety or major depressive disorder. Analyses were also stratified by gender.
Results
Treatment access was more likely in those who reported use of self-help strategies, with university-level education and those from less economically advantaged circumstances (household income £100 000). Men who self-medicated and/or had a vocational qualification were also less likely to seek treatment.
Conclusions
This work on retrospective reports of treatment-seeking and treatment receipt at any time of life replicates known associations with treatment-seeking and treatment receipt during time of treatment need. More work is required to understand whether improving rates of treatment-seeking improves prognostic outcomes for individuals with anxiety or depression
Assimilation of phytate-phosphorus by the extracellular phytase activity of tobacco (Nicotiana tabacum) is affected by the availability of soluble phytate
Phytate, the major organic phosphorus in soil, is not readily available to plants as a source of phosphorus (P). It is either complexed with cations or adsorbed to various soil components. The present study was carried out to investigate the extracellular phytase activities of tobacco (Nicotiana tabacum variety GeXin No.1) and its ability to assimilate external phytate-P. Whereas phytase activities in roots, shoots and growth media of P i-fed 14-day-old seedlings were only 1.3-4.9% of total acid phosphatase (APase) activities, P starvation triggered an increase in phytase secretion up to 914.9 mU mg -1 protein, equivalent to 18.2% of total APase activities. Much of the extracellular phytase activities were found to be root-associated than root-released. The plants were not able to utilize phytate adsorbed to sand, except when insoluble phytate salts were preformed with Mg 2+ and Ca 2+ ions for supplementation. Tobacco grew better in sand supplemented with Mg-phytate salts (31.9 mg dry weight plant -1; 0.68% w/w P concentration) than that with Ca-phytate salts (9.5 mg plant -1; 0.42%), presumably due to its higher solubility. We conclude that insolubility of soil phytate is the major constrain for its assimilation. Improving solubility of soil phytate, for example, by enhancement of citrate secretion, may be a feasible approach to improve soil phytate assimilation. © Springer 2006.postprin
Spectroscopy around Ca
Expérience GANILInternational audienceAn experiment was performed to study excited states in neutron-deficient nuclei around Ca. A one-neutron knockout reaction was used to produce Ca ions from a Ca secondary beam, and in-beam -rays were measured. The energy in Ca is compared to the mirror nucleus S to deduce information on the isospin dependence of the nuclear force near the proton drip line. The energy of the first excited state in Ca and the cross section for the 1-neutron knock-out reaction from Ca at 45 · AMeV were obtained. Furthermore, for two other = −2 nuclei, S and Ar, the de-excitation of the first state has been observed
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