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A key challenge in realizing practical quantum networks for long-distance quantum communication involves robust entanglement between quantum memory nodes connected by fibre optical infrastructure1–3. Here we demonstrate a two-node quantum network composed of multi-qubit registers based on silicon-vacancy (SiV) centres in nanophotonic diamond cavities integrated with a telecommunication fibre network. Remote entanglement is generated by the cavity-enhanced interactions between the electron spin qubits of the SiVs and optical photons. Serial, heralded spin-photon entangling gate operations with time-bin qubits are used for robust entanglement of separated nodes. Long-lived nuclear spin qubits are used to provide second-long entanglement storage and integrated error detection. By integrating efficient bidirectional quantum frequency conversion of photonic communication qubits to telecommunication frequencies (1,350 nm), we demonstrate the entanglement of two nuclear spin memories through 40 km spools of low-loss fibre and a 35-km long fibre loop deployed in the Boston area urban environment, representing an enabling step towards practical quantum repeaters and large-scale quantum networks.

Shockwave data on mineral‐forming compounds such as Mg2SiO4are essential for understanding the interiors of Earth and other planets, but correct interpretation of these data depends on knowing the phase assemblage being probed at high pressure. Hence, direct observations of the phase or phases making up the measured states along the forsterite Hugoniot are essential to assess whether kinetic factors inhibit the achievement of the expected equilibrium, phase‐separated assemblage. Previous shock recovery experiments on forsterite, which has orthorhombic space group Pbnm, show discrepant results as to whether forsterite undergoes segregation into its equilibrium phase assemblage of compositionally distinct structures upon shock compression. Here we present the results of plate impact experiments on polycrystalline forsterite conducted at the Dynamic Compression Sector of the Advanced Photon Source. In situ X‐ray diffraction measurements were used to probe the crystal structure(s) in the shock state and to investigate potential decomposition into periclase and bridgmanite. In contrast to previous interpretations of the forsterite shock Hugoniot, we find that forsterite does not decompose but instead reaches the forsterite III structure, which is a metastable structure of Mg2SiO4with orthorhombic space group Cmc21. Chemical segregation of forsterite does not occur on the microsecond timescalesKinetic effects determine the phases present on the forsterite Hugoniot up to 73 GPa

Abstract: Objectives To confirm the feasibility of nurse practitioner interventionin non-high-risk patients with recent myocardial infarction (MI). Design Observational study. Setting Acute coronary care unit in a teaching hospital. Methods We performed an open-label feasibility study to identify non-high-risk MI patients and evaluate the outcome of a new nurse practitioner intervention programme. The initial pilot phase served to identify the non-high-risk population. In the subsequent confirmation phase, 500 consecutive non-high-risk post-MI patients with preserved LV function without heart failure were included to receive nurse practitioner management. The nurse practitioner intervention started on transfer from the coronary care unit to the cardiology ward and continued thereafter for up to 30 days. Main outcome measures Time to first event analysis of death from all causes or repeat myocardial infarction. Results 500 Patients without signs of heart failure or depressed LV function were identified as nonhigh- risk and eligible for inclusion in the nurse practitioner intervention programme. In the implementation phase, none of the patients died and 0.9% developed a repeat myocardial infarction after 30 days of follow-up. Compared with the pilot phase, patients in the implementation phase spent fewer days in hospital (mean 11.1 versus 6.2 days; p<0.001). Conclusion It is feasible to identify non-high-risk post-MI patients, who can be managed adequately by a nurse practitioner. Embedding experienced nurse practitioners within critical care pathways may result in significant decreases in length of hospital stay. (Neth Heart J 2009;17:61-7.)

The influence of the tobacco additives diammonium hydrogen phosphate (DAP) and urea on the delivery and respiratory tract retention of nicotine and solanesol and on the uptake of nicotine into venous blood was investigated in 10 smokers under mouth-hold and 75 and 500 mL inhalation conditions. Three cigarettes with identical physical specifications were produced from a common lamina tobacco blend. The control cigarette contained nonammoniated reconstituted tobacco sheet (RTS), whereas DAP and other ammonia compounds were added to the RTS of the second cigarette. Urea was added to the tobacco of the third cigarette. The presence of DAP or urea in the test cigarettes did not significantly influence solanesol retention within the mouth during the mouth-hold condition. Nicotine retention within the mouth during the mouth-hold condition was, however, significantly higher for the DAP cigarette (64.3 ± 10.5%) than for the urea (53.3 ± 11.3%) or control cigarette (46.3 ± 8.6%), but this did not result in an increase in nicotine uptake into venous blood. Solanesol retentions during the 75 and 500 mL inhalation volume conditions and nicotine retentions during the 75 mL inhalation volume condition were not significantly different for the three cigarette types. Although the nicotine retention approached 100% with each cigarette type during the 500 mL inhalation condition, the nicotine retention for the urea-treated cigarette (99.6 ± 0.2%) was marginally, but statistically, significant, higher than for the control (99.1 ± 0.5%) and DAP-treated cigarettes (98.8 ± 0.6%). There were no statistically significant differences between the indices of nicotine uptake into venous blood for the three cigarette types in any of the inhalation conditions.

Cells of the obligately psychrophilic yeast Leucosporidium stokesii were subjected to permissive (15 and 20 degrees C) and restrictive (23 and 25 degrees C) temperatures to determine the event(s) responsible for the low maximum growth temperature of this organism. An investigation of subcellular morphology by nuclear staining revealed that buds formed at 20 degrees C were anucleate but showed nuclear migration within the parent cell. Cells incubated initially at 23 degrees C and then shifted down to a permissive growth temperature of 15 degrees C in the presence of a deoxyribonucleic acid (DNA) synthesis inhibitor, hydroxyurea, confirmed the observation that the anucleate condition of atypical buds was the result of temperature-sensitive DNA synthesis. Concomitantly, the incorporation of labeled adenine into DNA was inhibited at 23 and 25 degrees C. The synthesis of ribonucleic acid, however, was enhanced at 23 degrees C but impaired at 25 degres C. Similarly, protein synthesis was unaffected at either restrictive temperature.

The obligately psychrophilic yeast, Leucosporidium stokesii increased in size, produced irregular wall growth and formed atypical buds when incubated within one to three degrees above 20 °C, the maximum growth temperature. Incubation of cells anaerobically or aerobically in the presence of 2,4-dinitrophenol at the elevated temperatures prevented the development of atypical buds. An investigation of subcellular morphology revealed that the atypical bud was anucleate, did not form a septum between bud and parent cell and produced numerous cytoplasmic vesicles. On shift-down to 15 °C, the optimum growth temperature, nuclear division, migration and septum formation resumed.

Exposure to tobacco smoke is measured by a variety of invasive and noninvasive techniques. Our purpose was to examine how well some of these measures correlated when obtained simultaneously from the same subjects. On three occasions, six subjects were studied while they were smoking a single cigarette after 24 hr of abstinence. There were positive correlations between increases in heart rate and plasma nicotine concentrations and between percentage carboxyhemoglobin and exhaled carbon monoxide. Although residual cotinine was readily detected in samples of plasma before the subjects smoked, there was an increase in mean levels, with a peak approximately 1 hr after smoking. Urinary concentrations of nicotine, cotinine, and nicotine-1′-N-oxide and thiocyanate levels in plasma and saliva were essentially unchanged by smoking a single cigarette. Data on smoke generation and nicotine retention in cigarette butts correlated poorly with all other measures of smoke uptake.

B cells are induced to antibody production by antigens or by mitogens, such as lipopolysaccharide (LPS). We observed a mutually antagonistic relationship between activation through the antigen-receptor (AgR) and LPS-receptor (LPSR) in vitro. Prior exposure of B cells to AgR-ligating antibody prevented antibody forming cell (AFC) production induced by LPS, but not that induced by specific antigen (SRBC, TNP-Ficoll, or TNP-LPS). AFC production induced by antigen could be abrogated by concomitant exposure to LPS; the shutdown of the antigen-driven response was apparent when LPS-induced AFC were prevented by pre-exposure to antibody against the AgR. The ability of signaling through the AgR to inhibit antibody production stimulated by LPS was seen in DBA/2 and BALB/c mouse strains, and not in the New Zealand Black (NZB) strain. The results suggest that mutual antagonism is distinct from other forms of immune hyporesponsiveness, and that defects in antagonism may be a factor in the development of autoimmune disease.

The effect of Cyclosporine (CsA) on the in vivo cell-mediated immune response to donor antigens was examined sequentially following cadaveric renal transplantation in both immunologically naive and specifically sensitized allograft recipients. Cytotoxic T lymphocytes (CTL) exhibiting preferential specificity for donor antigens were detected in the peripheral blood of all patients receiving azathioprine (AZA) immunosuppression by two weeks posttransplant, disappearing progressively over the first three months with clinical quiescence. In contrast, the generation of donor-reactive CTL was significantly diminished in incidence (P=0.05) and in magnitude (P=0.004) in subjects receiving CsA. CTL were detected in only 36 of patients by two weeks posttransplant, and were not detectable in any CsA-treated patient after the sixth posttransplant week. The ability of CsA to inhibit clonal reexpansion of CTL was examined both in vitro and in vivo in subjects exhibiting prior sensitization to donor antigens. In vitro, CsA caused a dose-dependent inhibition of accelerated (72-hr MLC) CTL generation following restimulation with donor spleen cells, which was quantitatively identical to that in parallel cultures using responder PBL from non-sensitized individuals. In vivo, CsA produced a rapid disappearance of circulating CTL posttransplant in patients who exhibited specific cell-mediated sensitization to the graft donor, as evidenced by the presence of circulating donor-reactive CTL prior to transplantation. In contrast, in patients receiving AZA there was a rapid increase in donor-reactive CTL in the peripheral blood following transplantation. CTL persisted for six weeks or longer, and two of four patients lost the graft to irreversible acute rejection within the first four weeks.

Induction of cytoplasmic pyruvate decarboxylase (PDC) in Candida utilis increases with culture age throughout aerobic logarithmic phase growth on glucose and is due to oxygen depletion. Resting cells, grown on ethanol or acetate, fail to initiate PDC synthesis for two to three hours following anaerobic suspension in glucose although these cells are capable of glucose uptake. PDC induction occurs only at permissive growth temperatures, i.e., 5 ° C to 35 ° C. A preliminary characterization of the enzyme indicates an activity optimum of 35 ° C and a lack of any regulatory properties.

The induction of fermentation was studied in Candida utilis, a Crabtree-negative, respiratory yeast. This process occurs under oxygen-limiting conditions in the presence of a fermentable substrate and is the result of de novo enzyme synthesis. Induction occurs at permissive growth temperatures and its inhibition at 45 ° C is accompanied by loss of ability to take up glucose. The ability to be induced to an increased fermentative state is characteristic of all Crabtree-negative yeasts observed with the exception of an obligate aerobe, Hansenula wingei. No similar process occurs in the Crabtree-positive yeasts.

Penicillium corylophilum Dierckx was isolated from sludge collected at the interface of an aqueous, copper-bearing leachate and an organic, kerosene based, ion exchange solvent. The organism assimilated kerosene and various straight chain and cyclic hydrocarbons including dodecane, hexadecane, octadecane, toluene, benzene, and cyclohexane. Assimilation of kerosene and hexadecane was optimal at pH 2 and was stimulated by yeast extract.

In electron micrographs it could be shown that hazelnut (Corylus avellana) pollen grains are covered on their surface by a diffusible 10 nm thick lamellar layer. On pollen surface as well as in pollen extract this layer could be precipitated and stained by the polycationic dye Cuprolinic blue. By subsequent application of both immunogold labeling with serum from a hay-fever patient allergic to tree pollen grains and histochemical detection with Cuprolinic blue this pollen surface layer proved to be an effective antigen.

Summary Using serum from human atopic individuals with a sufficiently high titre of IgE and IgG antibodies to birchor hazel-pollen allergens and antigens, the localization of IgE binding sites in birch- and hazel-pollen grain was determined by pre- and post-embedding electron microscopic immunoautoradiography with 125J-anti-IgE, whereas the IgG binding sites were localized in ultrathin sections of birch-pollen grains by the protein-A/gold technique. Concerning the distribution patterns of both IgE/IgG binding sites within the pollen grains, no difference could be observed in the dormant pollen grain: Labelling was found in the exine part of the pollen wall and throughout the highly condensed cytoplasm except for starch grains and lipid droplets. The intine part and the germination pores were almost completely unlabelled. In pollen grains which had been soaked in a hypotonic buffer for 15 min, however, IgE binding sites were predominantly localized within the intine and the germination pores. The specificity of the labelling reactions and the observed differences in the localization patterns are discused.

Sinclair, N. A. (Washington State University, Pullman), and J. L. Stokes. Isolation of obligately anaerobic psychrophilic bacteria. J. Bacteriol. 87:562–565. 1964.—A total of 11 strains of strictly anaerobic psychrophilic bacteria have been isolated from soil, mud, and sewage. The organisms grow well at 0 C in liquid and on solid media, and grow only in the complete absence of oxygen. On the basis of shape, sporulation, flagellation, and strictly anaerobic growth, all of the organisms were classified as strains of Clostridium. Some of the biochemical properties of the strains and the effect of temperature on growth are described.

Sinclair, N. A. (Washington State University, Pullman) and J. L. Stokes. Factors which control maximal growth of bacteria. J. Bacteriol. 83:1147–1154. 1962.—In a chemically defined medium containing 1% glucose and 0.1% (NH4)2SO4, both of these compounds are virtually exhausted by the growth of Pseudomonas fluorescens. If these carbon, energy, and nitrogen sources are added back to the culture filtrate, maximal growth to the level of the original culture is obtained. This process can be repeated several times with the same results. Eventually, however, the supply of minerals in the culture limits growth. When the nutrient levels are raised to 3% glucose and 0.3% (NH4)2SO4, lack of oxygen and low pH limit growth before the supply of nutrients is exhausted. There is no evidence that specific autoinhibitory substances are produced either in chemically defined or complex nitrogenous media or that physical crowding of the cells limits growth. The results with Escherichia coliare similar to those with P. fluorescens. However, after a few growth cycles aerobically and after only one growth cycle anaerobically, inhibitory substances, probably organic acids, accumulate and limit growth.

Sinclair, N. A. (Washington State University, Pullman) and J. L. Stokes. Role of oxygen in the high cell yields of psychrophiles and mesophiles at low temperatures. J. Bacteriol. 85:164–167. 1963.—Psychrophilic and mesophilic bacteria produce maximal cell crops in stationary cultures at temperatures 10 to 20 C below those at which growth is most rapid. Our data indicate that O2is rapidly depleted to growth-limiting levels in stationary cultures, and that the higher cell yields at the lower temperatures are due simply to the increased solubility and, therefore, availability of O2. This conclusion is supported by the observation that equal cell crops are produced at high and low temperatures when cultures are vigorously aerated so that O2is not limiting, and also when facultative bacteria are grown anaerobically so that there is no O2to exert an effect.

Deep eutectic solvents (DESs) are promising electrolytes for electrochemical redox reactions, which can be used in redox flow batteries (RFBs). However, in some systems like the Fe2+/3+redox reaction in ethaline, traditional Tafel-based kinetic analysis generates unreasonable kinetic parameters (i.e., large anodic/cathodic charge transfer coefficients (?a, ?c) along with low exchange current densities (i0)). This hinders a comprehensive kinetic and kinetic mechanism study. Here, we perform a detailed investigation of the Tafel analysis using a series of synthetic rotating disk electrode (RDE) data. We find the Tafel analysis only works well when i0< 0.57 ilim(limiting current density) in our scenario and leads to abnormal kinetic values once i0exceeds this limiting value. Thus, we propose an extended Butler-Volmer (ex-BV) analysis based on modern non-linear fitting techniques to obtain the actual kinetic parameters for such systems. The results show that this method fits the RDE data closely and generates reliable ?a, ?cand i0values, demonstrating that it is a good replacement for traditional Tafel analysis for kinetic studies in high-viscosity electrolytes such as DES systems.

The Ag/AgCl reference electrode is commonly used in choline chloride based deep eutectic solvents. However, we found it undergoes significant potential shifts in electrochemical tests which previous reports largely ignored. In this work, we studied the degradation mechanism leading to its instability. Results show that due to the high Cl−concentration in ethaline, the AgCl film easily dissolves and forms AgCl2−species causing a potential shift. Therefore, we suggest a [Fe(CN)6]3−/[Fe(CN)6]4−reference electrode based on the reversibility and low diffusivity of [Fe(CN)6]3−/[Fe(CN)6]4−redox couple in ethaline, which was demonstrated to be reliable and stable over weeks of operation.

EARLY effects of carcinogenic hydrocarbons on the cell cycle and on deoxyribonucleic acid (DNA) synthesis have been noted by several authors. McCarter and Quastler1,2found that 7,12-dimethylbenz[α]anthracene (DMBA) decreases the rate of incorporation of 3H-thymidine into DNA and prolongs the DNA synthetic phase of the generation cycle of mouse epidermal cells. Evensen3found that 3-methylcholanthrene alters the proportion of epidermal cells labelled with 3H-thymidine in the hairless mouse. Jensen et al.4reported a reduction in uptake of 3H-thymidine in various tissues of the mouse following the administration of DMBA, including some tissues in which tumours do not usually arise after treatment with this agent. Elgjo5reported that 3-methylcholanthrene changes the mitotic phase of the cell cycle over an eleven-week period. We now report an early effect of DMBA on the synthesis of ribonucleic acid (RNA) in mouse skin.

SPECIFIC antibody, passively transferred, has the capacity to inhibit the production of the specific immune response (reviewed in ref. 1), and may even terminate a response2. There have been several reports dealing with the ability of F(ab′)2antibody (the antibody fragment which has the two antigen-binding sites but lacks the Fc fragment) to suppress the primary immune response (refs. 3–5, and F. J. Dixon, quoted in ref. 1). The specificity of this type of immunosuppression is best explained in terms of antigen–antibody binding so that the antigenic site is masked, and so it was not surprising that F(ab′)2was found to induce antibody-mediated suppression of the immune response. In an initial attempt at preparing F(ab′)2antibody, however, we found that all the suppressive activity in the F(ab′)2preparation could be explained on the basis of contaminating whole 7S antibody. We report here the results of experiments in which the 5S F(ab′)2antibody digested by pepsin and remaining undigested 7S antibody were separated on sucrose gradients and their activities in suppressing the primary antibody response tested separately.

ANTIBODY-MEDIATED immunosuppression is no longer thought to be solely due to the masking of antigen by antibody. The hypothesis that events beyond the binding of antibody to antigen are operative in antibody-mediated immunosuppression is supported by the following facts. (1) Antigen-masking need not be complete to obtain pronounced suppression of immune responses1,2; (2) interactions between antigenic determinants on the same immunogenic particle (molecules to whole cells) take place so that suppression of immune responses to one antigenic determinant may occur with the binding of antibody to another non-cross-reacting and topographically separate antigenic determinant3–5; (3) parts of the antibody molecule, other than that involved in the binding of antigen, are important in the regulation of the immune response by antibody6–9; (4) immunosuppression does not necessarily become more pronounced when the dose of passively administered antibody is increased but proceeds through an optimum beyond which less suppression is observed10,11,13,14; and (5) immunosuppression by antibody can lead to inactivation of the antigen-sensitive cell population12–14. Similarly, immunological tolerance is no longer thought to be the simple elimination of immunologically competent cells by antigen. The following data suggest a more complex mechanism in the induction of immunological tolerance. (1) Animals which demonstrate tolerance seem to possess both sensitized lymphoid cells and soluble factors (antibodies or antigens) which prevent the sensitized cells from functioning15,16; (2) induction of tolerance is often preceded by the production of measurable antibody31or antibody-forming cells17,18; (3) induction of tolerance requires the presence of a functioning complement system19; and (4) cells capable of binding antigen remain, or may increase, during the attainment of the tolerant state20–23. Consequently, it now seems possible that these two hyporeactive states, antibody mediated immunosuppression and immunological tolerance, share common characteristics and common modes of induction.

The injection of 60 micrograms of 9,10-dimethyl-1,2-benzanthracene into newborn mice gave rise to a very high incidence of malignant thymomas. The tumor incidence was directly related to the dose of the carcinogen. The neonatal injection of the carcinogen also resulted in a depression in the immune response when the animals were challenged with an antigen as early as 4 weeks or as late as 11 weeks after administration of the carcinogen.

Purpose:To present a case of two siblings diagnosed with Congenital Horner's Syndrome. The condition developing in related patients has only been previously described once in the literature.