Network Synthesis of Linear Dynamical Quantum Stochastic Systems

The purpose of this paper is to develop a synthesis theory for linear dynamical quantum stochastic systems that are encountered in linear quantum optics and in phenomenological models of linear quantum circuits. In particular, such a theory will enable the systematic realization of coherent/fully quantum linear stochastic controllers for quantum control, amongst other potential applications. We show how general linear dynamical quantum stochastic systems can be constructed by assembling an appropriate interconnection of one degree of freedom open quantum harmonic oscillators and, in the quantum optics setting, discuss how such a network of oscillators can be approximately synthesized or implemented in a systematic way from some linear and non-linear quantum optical elements. An example is also provided to illustrate the theory.Comment: Revised and corrected version, published in SIAM Journal on Control and Optimization, 200

Management Options of Colonoscopic Splenic Injury

Injury to the spleen during routine colonoscopy is an extremely rare injury. Diagnosis and management of the injury has evolved with technological advances and experience gained in the management of splenic injuries sustained in trauma. Of the 37 reported cases of colonoscopic splenic injury, 12 had a history of prior surgery or a disease process suggesting the presence of adhesions. Only 6 had noted difficulty during the procedure, and 31 patients experienced pain, shock, or hemoglobin drop as the indication of splenic injury. Since 1989, 21/24 (87.5%) patients have been diagnosed initially using computed tomography or ultrasonography. Overall, only 27.8% have retained their spleens. None have experienced as long a delay as our patient, nor have any had an attempt at percutaneous control of the injury. This report presents an unusual case of a rare complication of colonoscopy and the unsuccessful use of one nonoperative technique, and reviews the experience reported in the world literature, including current day management options

Sodium fluoroacetate (compound 1080) uptake by Puha, a culturally-important food plant

Sodium fluoroacetate (Compound 1080) is a key tool in the control of possums, and the most extensively used vertebrate pesticide in New Zealand (Livingstone 1994; Morgan 1994a, b; Thomas 1994; Gillies and Pierce 1999; Powlesland et al. 1999; Sherley et al. 1999; Styche and Speed 2002). The most common method of control using this pesticide is via aerial application of cereal or carrot baits containing 1080 (Eason et al. 2000). This is a cost effective means of reducing possum populations by more than 90% (Eason et al. 1994, Veltman and Pinder 2001). Despite the efficiency of aerial 1080 application for reducing possum population numbers, support amongst Māori is mixed. In general, Māori oppose the use of toxins in the environment, despite the benefits to be had through the control of pests. In particular, there is much opposition around the aerial use of 1080 (Ogilvie et al. in press). Para (1999) documented concerns of Māori regarding the fate of 1080 in wild harvested kai (food) species. The risk of secondary poisoning of people using kai resources has previously been identified as key research by the Animal Health Board (AHB), Environmental Risk Management Authority (ERMA) and Māori. During aerial application of 1080 baits, there is the possibility that 1080 may leach from baits and be taken up by nearby plants (Atzert 1971; Rammel and Fleming 1978). More recent laboratory research has shown that 1080 can be taken up by terrestrial and aquatic plants, including Myriophyllum triphyllum, a native aquatic New Zealand plant (Ogilvie et al. 1995); Elodea canadensis, an introduced aquatic species (Ogilvie et al. 1996); and broadleaf and ryegrass, both terrestrial species (Ogilvie et al. 1998). In a field setting where a simulated aerial 1080 operation has been conducted, low concentrations of 1080 were found in Coprosma robusta, or karamuramu, a native species used as medicine by Māori; however no 1080 was found in Asplenium bulbiferum, or pikopiko, a native species commonly consumed by Māori (Ogilvie et al. 2006). This report is part of a research programme conducted to investigate the uptake and persistence of 1080 in watercress and puha. This report focuses only on data generated from the puha component of this work. The watercress component will be reported at a later date.Research was undertaken for the Animal Health Board Inc. (AHB) under Contract R-80694 “Uptake of 1080 by Watercress and Puha” by Lincoln University

Pathogenesis of Murine Gammaherpesvirus-68 Infection in Interleukin-6-Deficient Mice

AbstractMurine gammaherpesvirus-68 (MHV-68) induces high levels of interleukin (IL)-6 production in both naive and primed lymphocyte populations. Mice that are homozygous (−/−) for deletion of the IL-6 gene were used to investigate the role of this cytokine in MHV-68 infection. The results showed that IL-6 is not essential for clearance of infectious MHV-68 from the lung or for the establishment, or control, of viral latency. Both IL-6 +/+ and −/− mice eliminated replicating virus from the respiratory tract within 15 days of infection, and their lungs remained clear of infectious virus for ≥150 days. Interestingly, the IL-6 −/− mice had both increased numbers of natural killer (NK)1.1+ cells and higher levels of NK cell activity than the +/+ controls at 10–15 days after infection. However, there was no difference in the cytotoxic T cell activity between the two groups of mice. Levels of latent virus were comparable in IL-6 +/+ and −/− mice over the time course studied. Furthermore, analysis of the numbers, types, and activation status of the various leukocyte subsets (other than NK cells) in the bronchoalveolar lavage population, lymph nodes, and spleens of +/+ and −/− mice revealed no striking differences. Apart from the expected lack of IL-6, cytokine profiles were not dramatically altered in IL-6 −/− mice. Thus, there is no evidence for an obligatory role for IL-6 in T cell activation during infection with MHV-68

A novel method to identify and characterise peptide mimotopes of heat shock protein 70-associated antigens

The heat shock protein, Hsp70, has been shown to play an important role in tumour immunity. Vaccination with Hsp70-peptide complexes (Hsp70-PCs), isolated from autologous tumour cells, can induce protective immune responses. We have developed a novel method to identify synthetic mimic peptides of Hsp70-PCs and to test their ability to activate T-cells. Peptides (referred to as "recognisers") that bind to Hsp70-PCs from the human breast carcinoma cell line, MDA-MB-231, were identified by bio-panning a random peptide M13 phage display library. Synthetic recogniser peptides were subsequently used as bait in a reverse bio-panning experiment to identify potential Hsp70-PC mimic peptides. The ability of the recogniser and mimic peptides to prime human lymphocyte responses against tumour cell antigens was tested by stimulating lymphocytes with autologous peptide-loaded monocyte-derived dendritic cells (DCs). Priming and subsequent stimulation with either the recogniser or mimic peptide resulted in interferon-γ (IFN-γ) secretion by the lymphocytes. Furthermore, DCs loaded with Hsp70, Hsp70-PC or the recogniser or the mimic peptide primed the lymphocytes to respond to soluble extracts from breast cells. These results highlight the potential application of synthetic peptide-mimics of Hsp70-PCs, as modulators of the immune response against tumours

Creating and publicising a web-based database of 1080 and taonga species information: final report

The research was aimed at producing a web-based database of information on 1080 impacts on non-target species, identified as important by Maori. The research reported here was carried out between August 2006 and June 2007, and was undertaken by a collaborative team of researchers from Lincoln University, Landcare Research Ltd, Lake Waikaremoana Hapu Restoration Trust, and Tuhoe Tuawhenua Trust

Sources of carbonaceous aerosols and deposited black carbon in the Arctic in winter-spring: implications for radiative forcing

We use a global chemical transport model (GEOS-Chem CTM) to interpret observations of black carbon (BC) and organic aerosol (OA) from the NASA ARCTAS aircraft campaign over the North American Arctic in April 2008, as well as longer-term records in surface air and in snow (2007–2009). BC emission inventories for North America, Europe, and Asia in the model are tested by comparison with surface air observations over these source regions. Russian open fires were the dominant source of OA in the Arctic troposphere during ARCTAS but we find that BC was of prevailingly anthropogenic (fossil fuel and biofuel) origin, particularly in surface air. This source attribution is confirmed by correlation of BC and OA with acetonitrile and sulfate in the model and in the observations. Asian emissions are the main anthropogenic source of BC in the free troposphere but European, Russian and North American sources are also important in surface air. Russian anthropogenic emissions appear to dominate the source of BC in Arctic surface air in winter. Model simulations for 2007–2009 (to account for interannual variability of fires) show much higher BC snow content in the Eurasian than the North American Arctic, consistent with the limited observations. We find that anthropogenic sources contribute 90% of BC deposited to Arctic snow in January-March and 60% in April–May 2007–2009. The mean decrease in Arctic snow albedo from BC deposition is estimated to be 0.6% in spring, resulting in a regional surface radiative forcing consistent with previous estimates.Earth and Planetary SciencesEngineering and Applied Science

Radiation tolerance of two-dimensional material-based devices for space applications

Characteristic for devices based on two-dimensional materials are their low size, weight and power requirements. This makes them advantageous for use in space instrumentation, including photovoltaics, batteries, electronics, sensors and light sources for long-distance quantum communication. Here, we present for the first time a comprehensive study on combined radiation effects in earth's atmosphere on various devices based on these nanomaterials. Using theoretical modeling packages, we estimate relevant radiation levels and then expose field-effect transistors, single-photon sources and monolayers as building blocks for future electronics to gamma-rays, protons and electrons. The devices show negligible change in performance after the irradiation, suggesting robust suitability for space use. Under excessive $\gamma$-radiation, however, monolayer WS$_2$ showed decreased defect densities, identified by an increase in photoluminescence, carrier lifetime and a change in doping ratio proportional to the photon flux. The underlying mechanism was traced back to radiation-induced defect healing, wherein dissociated oxygen passivates sulfur vacancies

Does hypoglycemia following a glucose challenge test identify a high risk pregnancy?

<p>Abstract</p> <p>Objective</p> <p>An association between maternal hypoglycemia during pregnancy with fetal growth restriction and overall perinatal mortality has been reported. In a retrospective pilot study we found that hypoglycemia was linked with a greater number of special care/neonatal intensive care unit admissions and approached significance in the number of women who developed preeclampsia. That study was limited by its retrospective design, a narrow patient population and the inability to perform multivariate analysis because of the limitations in the data points collected. This study was undertaken to compare the perinatal outcome in pregnancies with hyoglycemia following a glucose challenge test (GCT) to pregnancies with a normal GCT.</p> <p>Methods</p> <p>Obstetric patients (not pre-gestational diabetics or gestational diabetes before 24 weeks were eligible. Women with a 1 hour glucose ≤ 88 mg/dL (4.8 m/mol) following a 50-gram oral GCT were matched with the next patient with a 1 hour glucose of 89–139 mg/dL. Pregnancy outcomes were evaluated.</p> <p>Results</p> <p>Over 22 months, 436 hypoglycemic patients and 434 normal subjects were identified. Hypoglycemia was increased in women < 25 (p = 0.003) and with pre-existing medical conditions (p < 0.001). Hypoglycemia was decreased if pre-pregnancy BMI ≥ 30 (p = 0.008).</p> <p>Preeclampsia/eclampsia was more common in hypoglycemic women. (OR = 3.13, 95% CI 1.51 – 6.51, p = 0.002) but not other intrapartum and perinatal outcomes.</p> <p>Conclusion</p> <p>Hypoglycemic patients are younger, have reduced pre-pregnancy weight, lower BMIs, and are more likely to develop preeclampsia than normoglycemic women.</p