Compact and robust cold atom sources are increasingly important for quantum research, especially for transferring cutting-edge quantum science into practical applications. In this study, we report on a novel scheme that uses a metasurface optical chip to replace the conventional bulky optical elements used to produce a cold atomic ensemble with a single incident laser beam, which is split by the metasurface into multiple beams of the desired polarization states. Atom numbers ~107 and temperatures (about 35 μK) of relevance to quantum sensing are achieved in a compact and robust fashion. Our work highlights the substantial progress toward fully integrated cold atom quantum devices by exploiting metasurface optical chips, which may have great potential in quantum sensing, quantum computing, and other areas.

Sensitivity to nickel, cobalt, and chromium is common among the general population. The identification of these sensitivities is generally by the detection of cell-mediated immunity. Detection of humoral immunity to these metals has rarely been undertaken because suitable assays are not available. To further our knowledge about the systemic humoral immune system response to weak hapten-syngeneic or allogeneic protein conjugates (corrosion and wear products of metallic orthopedic devices), a sensitive enzymelinked immunosorbent assay (ELISA) method for testing for antibody (humoral immunity) to metals was developed. Microtiter plates were coated with human serum albumin (HSA) or glutathione (GSH) and then conjugated with metal ions. Plates coated with HSA or GSH and without metal ions served as background controls. An indirect ELISA method was used to detect antibody binding. Patients bearing cobalt-chromium alloy devices were considered to be the most likely candidates as sources of antibody to metal and were used to document the usefulness of the test. Specificity of the test was documented by inhibition studies with these metal ions in the ELISA assay. The serum samples of 10 patients were screened for the presence of Cr-, Co-, or Ni-specific antibody at various periods up to 5.5 years after implantation of F-75 cobalt alloy total joint replacements. All patients had implants that were functioning well. The pre-and postimplantation humoral immune profiles of patients were determined and compared with each preimplantation control and with a pooled normal serum sample. This study presents evidence that metalprotein complex-specific antibodies can be detected. The clinical implications remain to be determined. 0 1994 John INTRODUCTIONMetal sensitivity among the general population is fairly common, with sensitivity to nickel being the most frequent, followed by cobalt and chromium. These sensitivities are generally of the cell-mediated type. In previously sensitized subjects, skin contact or systemic exposure can trigger cutaneous and/or systemic hypersensitivity reactions. Early studies on the possible relation between sensitivity to metal and *To whom correspondence should be addressed at: Department of Biomedical Engineering, 504 Wickenden, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH 44106-7207. problems with total joint replacement aroused considerable interest. Since then, metal sensitivity has been implicated by some researchers as contributing to aseptic loosening and failure of joint prostheses, but the reports on the magnitude of the problem are contradictory.Elevated levels of cobalt, chromium, nickel, and titanium are found in the blood, urine, and tissue at implant and remote site of patients with Co-Cr and Ti-base alloy total joint replacement components. Metal ions may bind to tissue and interstitial fluid proteins as soon as they are released from the metallic ~ubstrate.~ Because albumin is the most abundant protein in serum and in interstitial tissue fluid, all the metals bi...

IntroductionThis study compared the effects of hydroxyethyl starch 130/0.4, hydroxyethyl starch 200/0.5, and succinylated gelatin on oxidative stress and the inflammatory response in a rodent hemorrhagic shock model.MethodsSodium pentobarbital-anesthetized adult male Wistar rats (200 g to 220 g) were subjected to a severe volume-controlled hemorrhage using arterial blood withdrawal (30 mL/kg to 33 mL/kg) and resuscitated with a colloid solution at the same volume as blood withdrawal (hydroxyethyl starch 130/0.4, hydroxyethyl starch 200/0.5, or succinylated gelatin). Arterial blood gas parameters were monitored. Malondialdehyde (MDA) content and myeloperoxidase (MPO) activity in the liver, lungs, intestine, and brain were measured two hours after resuscitation. The levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 in the intestine were also measured.ResultsInfusions of hydroxyethyl starch 130/0.4, but not hydroxyethyl starch 200/0.5 or succinylated gelatin, significantly reduced MDA levels and MPO activity in the liver, intestine, lungs and brain, and it also inhibited the production of TNF-α in the intestine two hours after resuscitation. However, no significant difference between hydroxyethyl starch 200/0.5 and succinylated gelatin was observed.ConclusionsHydroxyethyl starch 130/0.4, but not hydroxyethyl starch 200/0.5 or succinylated gelatin, treatment after hemorrhagic shock ameliorated oxidative stress and the inflammatory response in this rat model. No significant differences were observed after hydroxyethyl starch 200/0.5 or succinylated gelatin administration at doses of approximately 33 mL/kg.

Sensitivity to nickel, cobalt, and chromium is common among the general population. The identification of these sensitivities is generally by the detection of cell-mediated immunity. We have reported previously the use of an indirect enzyme-linked immunosorbent assay method to quantitate metal-specific antibodies in patients with total joint replacements. To study the haptenic potential of these metal ions, rabbit albumin-glutathione-metal complexes with chromium, cobalt, or nickel were injected into mice. The splenocytes from one mouse in each group which developed a strong antibody against GSH-metal complexes were isolated and fused with myeloma cells to produce monoclonal antibodies. Chromium, cobalt, and nickel antibodies had similar affinity and bound with the specific GSH-metal complex. There was very little cross-reactivity between these antibodies. An inhibition assay using these monoclonal antibodies was demonstrated to be a simple technique, suitable for quantitation of free metal in solution.

The effect of biomaterials on the superoxide-producing ability of neutrophils was studied. Human peripheral blood neutrophils were incubated with cobalt-base alloy (F-75) or polystyrene beads of a nonphagocytosable size. Respiratory burst activity was studied by measuring superoxide dismutase inhibitable reduction of cytochrome C. Neutrophils were found to release no more superoxide anion on incubation for up to 3 h with either material in a protein-free medium than controls without foreign material. However, the ability of neutrophils incubated with either biomaterial to subsequently respond to phorbol myristate acetate challenge was decreased (p less than 0.05). Chemical analysis of supernatants for the F-75 samples showed a high concentration of cobalt in the medium within 1 h of incubation. Minimal chromium and nickel was detected. No correlation could be demonstrated between metal in solution and the respiratory burst defect in neutrophils. Instead it appears that interaction of cells with either surface was the critical event in altering the response to phorbol myristate acetate. This observed functional defect may play an important role in rendering tissue around implanted biomaterials susceptible to infections.

Type A lactic acidosis resulted from hypoxic mitochondrial dysfunction is an independent predictor of mortality for critically ill patients. However, current therapeutic agents are still in shortage and can even be harmful. This paper reviewed data regarding lactic acidosis treatment and recommended that pyruvate might be a potential alkalizer to correct type A lactic acidosis in future clinical practice. Pyruvate is a key energy metabolic substrate and a pyruvate dehydrogenase (PDH) activator with several unique beneficial biological properties, including anti-oxidant and anti-inflammatory effects and the ability to activate the hypoxia-inducible factor-1 (HIF-1α) - erythropoietin (EPO) signal pathway. Pyruvate preserves glucose metabolism and cellular energetics better than bicarbonate, lactate, acetate and malate in the efficient correction of hypoxic lactic acidosis and shows few side effects. Therefore, application of pyruvate may be promising and safe as a novel therapeutic strategy in hypoxic lactic acidosis correction accompanied with multi-organ protection in critical care patients.

Er 3+ -doped Y 2 O 3 nanoparticles (NPs) are used to synthesize transparent ceramics by hot isostatic pressing. Two sizes of NPs are studied, and 40 nm NPs show better performance than 200 nm NPs in transparent ceramics syntheses. The axial optical transmission through millimeter thickness of the prepared ceramics is about 80% in the wavelength range of 1000–2000 nm. For a sample with 11.5 ppm Er 3+ , the inhomogeneous broadening of the 4 I 15/2 to 4 I 13/2 transition for the C 2 site is as low as 0.42 GHz (full width at half-maximum), and the homogeneous line width is 11.2 kHz at a temperature of 2.5 K and in a 0.65 T magnetic field. This indicates that a majority of Er 3+ ions are sitting in sites with very low structural disorder.

We propose two new methods to measure principal modes, or Eisenbud-Wigner-Smith eigenstates in optically scattering medium. Both methods use similar techniques as in quantum state tomography, and are based on direct measurement of temporal delays. The first method requires N² different input launching conditions, and only the mean signal delay of these input states are needed to obtain full information of the principal modes. When the mode delay differences are large and all modes are non-degenerate, a second method can be used, which only requires 3N - 2 input launching conditions.