Grosse Ile and the Irish Memorial National Historic Site, Parks Canada: A Case Study

Focuses on values and their protection by examining the place of values in management. Grosse Ile's management is still evolving, and the eventful first phases of planning are still fresh in the minds of staff

Stage progression and neurological symptoms in Trypanosoma brucei rhodesiense sleeping sickness: role of the CNS inflammatory response

Background: Human African trypanosomiasis progresses from an early (hemolymphatic) stage, through CNS invasion to the late (meningoencephalitic) stage. In experimental infections disease progression is associated with neuroinflammatory responses and neurological symptoms, but this concept requires evaluation in African trypanosomiasis patients, where correct diagnosis of the disease stage is of critical therapeutic importance. Methodology/Principal Findings: This was a retrospective study on a cohort of 115 T.b.rhodesiense HAT patients recruited in Eastern Uganda. Paired plasma and CSF samples allowed the measurement of peripheral and CNS immunoglobulin and of CSF cytokine synthesis. Cytokine and immunoglobulin expression were evaluated in relation to disease duration, stage progression and neurological symptoms. Neurological symptoms were not related to stage progression (with the exception of moderate coma). Increases in CNS immunoglobulin, IL-10 and TNF-α synthesis were associated with stage progression and were mirrored by a reduction in TGF-β levels in the CSF. There were no significant associations between CNS immunoglobulin and cytokine production and neurological signs of disease with the exception of moderate coma cases. Within the study group we identified diagnostically early stage cases with no CSF pleocytosis but intrathecal immunoglobulin synthesis and diagnostically late stage cases with marginal CSF pleocytosis and no detectable trypanosomes in the CSF. Conclusions: Our results demonstrate that there is not a direct linkage between stage progression, neurological signs of infection and neuroinflammatory responses in rhodesiense HAT. Neurological signs are observed in both early and late stages, and while intrathecal immunoglobulin synthesis is associated with neurological signs, these are also observed in cases lacking a CNS inflammatory response. While there is an increase in inflammatory cytokine production with stage progression, this is paralleled by increases in CSF IL-10. As stage diagnostics, the CSF immunoglobulins and cytokines studied do not have sufficient sensitivity to be of clinical value

Quantum optical signal processing in diamond

Controlling the properties of single photons is essential for a wide array of emerging optical quantum technologies spanning quantum sensing, quantum computing, and quantum communications. Essential components for these technologies include single photon sources, quantum memories, waveguides, and detectors. The ideal spectral operating parameters (wavelength and bandwidth) of these components are rarely similar; thus, frequency conversion and spectral control are key enabling steps for component hybridization. Here we perform signal processing of single photons by coherently manipulating their spectra via a modified quantum memory. We store 723.5 nm photons, with 4.1 nm bandwidth, in a room-temperature diamond crystal; upon retrieval we demonstrate centre frequency tunability over 4.2 times the input bandwidth, and bandwidth modulation between 0.5 to 1.9 times the input bandwidth. Our results demonstrate the potential for diamond, and Raman memories in general, to be an integrated platform for photon storage and spectral conversion.Comment: 6 pages, 4 figure

Storage of polarization-entangled THz-bandwidth photons in a diamond quantum memory

Bulk diamond phonons have been shown to be a versatile platform for the generation, storage, and manipulation of high-bandwidth quantum states of light. Here we demonstrate a diamond quantum memory that stores, and releases on demand, an arbitrarily polarized $\sim$250 fs duration photonic qubit. The single-mode nature of the memory is overcome by mapping the two degrees of polarization of the qubit, via Raman transitions, onto two spatially distinct optical phonon modes located in the same diamond crystal. The two modes are coherently recombined upon retrieval and quantum process tomography confirms that the memory faithfully reproduces the input state with average fidelity $0.784\pm0.004$ with a total memory efficiency of $(0.76\pm0.03)\%$. In an additional demonstration, one photon of a polarization-entangled pair is stored in the memory. We report that entanglement persists in the retrieved state for up to 1.3 ps of storage time. These results demonstrate that the diamond phonon platform can be used in concert with polarization qubits, a key requirement for polarization-encoded photonic processing

Storage and retrieval of ultrafast single photons using a room-temperature diamond quantum memory

We report the storage and retrieval of single photons, via a quantum memory, in the optical phonons of room-temperature bulk diamond. The THz-bandwidth heralded photons are generated by spontaneous parametric downconversion and mapped to phonons via a Raman transition, stored for a variable delay, and released on demand. The second-order correlation of the memory output is $g^{(2)}(0) = 0.65 \pm 0.07$, demonstrating preservation of non-classical photon statistics throughout storage and retrieval. The memory is low-noise, high-speed and broadly tunable; it therefore promises to be a versatile light-matter interface for local quantum processing applications.Comment: 6 pages, 4 figure

Protein-mediated dethreading of a biotin-functionalised pseudorotaxane

In this article, we describe the synthesis of new biotin-functionalised naphthalene derivatives 3 and 4 and their complexation behaviour with avidin and neutravidin using a range of analytical techniques. We have shown using 2-(4prime or minute-hydroxyazobenzene)benzoic acid displacement and ITC experiments{,} that compounds 3 and 4 have the propensity to form reasonably high-affinity bioconjugates with avidin and neutravidin. We have also demonstrated using 1H NMR{,} UV-vis and fluorescence spectroscopy that the naphthalene moiety of 3 and 4 facilitates the formation of pseudorotaxane-like structures with 1 in water. We have then investigated the ability of avidin and neutravidin to modulate the complexation between 1 and 3 or 4. UV-vis and fluorescence spectroscopy has shown that in both cases the addition of the protein disrupts complexation between the naphthalene moieties of 3 and 4 with 1

New proof-of-concept in viral inactivation: virucidal efficacy of 405 nm light against feline calicivirus as a model for norovirus decontamination

The requirement for novel decontamination technologies for use in hospitals is ever present. One such system uses 405 nm visible light to inactivate microorganisms via ROS-generated oxidative damage. Although effective for bacterial and fungal inactivation, little is known about the virucidal effects of 405 nm light. Norovirus (NoV) gastroenteritis outbreaks often occur in the clinical setting, and this study was designed to investigate potential inactivation effects of 405 nm light on the NoV surrogate, feline calicivirus (FCV). FCV was exposed to 405 nm light whilst suspended in minimal and organically-rich media to establish the virucidal efficacy and the effect biologically-relevant material may play in viral susceptibility. Antiviral activity was successfully demonstrated with a 4 Log10 (99.99%) reduction in infectivity when suspended in minimal media evident after a dose of 2.8 kJ cm−2. FCV exposed in artificial faeces, artificial saliva, blood plasma and other organically rich media exhibited an equivalent level of inactivation using between 50–85% less dose of the light, indicating enhanced inactivation when the virus is present in organically-rich biologically-relevant media. Further research in this area could aid in the development of 405 nm light technology for effective NoV decontamination within the hospital environment

Central Nervous System Parasitosis and Neuroinflammation Ameliorated by Systemic IL-10 Administration in Trypanosoma brucei-Infected Mice

Peer reviewedPublisher PD

Late Quaternary Paleoceanography and Sedimentary Environments in Hudson Strait

Airgun and high resolution Huntec seismic reflection profiles are interpreted to show up to 130 m of glacial, glaciomarine and postglacial sediments overlying bedrock. In a basin at the eastern entrance to Hudson Strait most of the surficial sediment was deposited during the last déglaciation, but in western Hudson Strait multiple till sequences from previous glaciations are recognized. Five acoustic units were identified, at least three of which were penetrated with piston cores. Foraminifera of the stratigraphically deepest core in the eastern basin indicate a proximal glaciomarine environment and a likely presence of an ice shelf. A 14C date of 8060 ± 70 yBP (TO 750) on molluscan shells gives a minimum age for the top of the acoustically laminated distal glaciomarine sediments. The early postglacial foraminifera suggest a period of increased influence of offshore bottom waters restricted to the deep eastern basin. The surface sediments of all cores contain species indigenous of colder and fresher inshore waters of the present time. The ratio of 18CV16O in the benthic foraminifer Cibicides lobatulus is herein related to bottom salinity. Downcore measurements of 8'8O on C. lobatulus tests indicate bottom paleosalinities lower by about 0.5%o shortly before the dated horizon of 8000 yBP. By this time Hudson Strait was sufficiently clear of glacial ice for establishment of the present tidal regime. The lower bottom salinities indicate that tidal mixing took place between glacial meltwater leaving Hudson Bay and the offshore counterflow. This process is thought to have reduced the sharpness of the salinity difference between the offshore water and the surface plume of Laurentide meltwater as it entered the ocean.L'utilisation d'un fusil à air comprimé et d'un dispositif explosif Huntec en sismique réflexion a permis d'obtenir des profils à haute résolution révélant que des sédiments glaciaires, glaciomarins et postglaciaires d'une épaisseur de 130 m surmontent la roche en place. Un bassin, à l'entrée est du détroit d'Hudson, renferme des sédiments de surface qui, pour la plupart, se sont déposés au cours de la dernière glaciation. On a relevé cinq unités acoustiques dont au moins trois ont été explorées par carottage. Les foraminifères de la carotte extraite, dans le bassin est, à la plus grande profondeur révèlent qu'existaient un milieu glaciomarin proximal et, vraisemblablement, une plate-forme de glace flottante. La datation au 14C fait remonter à 8060 ± 70 BP (TO 750) les coquilles de mollusques et confère ainsi un âge minimal à la portion supérieure des sédiments glaciomarins distaux, laminés par acoustique. Les foraminifères du début de la période postglaciaire laissent croire que les eaux profondes du large ont pendant un certain temps exercé une influence accrue sur les fonds du bassin de l'est. Dans toutes les carottes, les sédiments de surface renferment des espèces indigènes au milieu aquatique actuel, plus froid et moins salé. Le taux 18OZ16O trouvé chez le foraminifère benthique Cibicides lobatulus se rapporte ici à la salinité des fonds aquatiques. Plus bas, dans les carottes, on a relevé sur C. lobatulus un taux de 818O qui révèle une paléosalinité plus faible d'environ 0,5%o, précédant tout juste l'horizon daté à 8000 BP. À cette époque, le détroit d'Hudson était suffisamment libre de glace pour que s'établissent les marées telles qu'on les connaît actuellement. Plus bas encore, la salinité révèle que les eaux de fusion glaciaire provenant de la baie d'Hudson se sont mêlées aux contre-courants venus du large.Mit Hilfe eines Luftgewehrs und einer Huntec Explosionsanlage mit seismischer Reflexion gewonnene Profile mit hoher Auflôsung lassen bis zu 130 m glazialer, glaziomariner und postglazialer Sedimente erkennen, die den FeIs ùberlagern, In einem Bassin am ôstlichen Eingang zur Hudson-Meerenge ist der grôsste Teil der Oberflàchensedimente wâhrend der letzten Vereisung abgelagert worden, aber in der westlichen Hudson-Meerenge lassen sich vielfache Grundmorànen-Sequenzen von frùheren Vereisungen erkennen. Fùnf akustische Einheiten wurden identifiziert, von denen mindestens drei durch Kernbohrung ergrûndet wurden. Die Foraminifera des stratigraphisch tiefsten Kerns im ôstlichen Bassin weisen auf eine proximale glaziomarine Umwelt und die môgliche Existenz einer Eisdecke. Eine 14C Datierung von 8060 ± 70 Jahren v.u.Z. (bis 750) fur Molluskenschalen ergibt ein Minimalalter fur den oberen Teil der distalen glaziomarinen Sedimente, die durch Akustik eine blàttrige Struktur bekommen haben. Die frùhen postglazialen Foraminifera lassen auf eine Période wachsenden Einflusses des kùstenfernen Tiefwassers auf das tiefe ôstliche Bassin schliessen. Die Oberflàchensedimente aller Bohrkerne enthalten Gattungen, die spezifisch fur die kàlteren und frischeren Kùstengewàsser der gegenwârtigen Zeit sind. Der Anteil an 18OZ16O in dem benthischen Foraminifer Cibicides lobatulus ist hierin mit dem Salzgehalt auf dem Grund verbunden. Tiefer im Bohrkern hat man auf C. lobatulus Werte von 818O gefunden, was einen um etwa 0.5% geringeren Grund-Palàosalzgehalt ergibt, kurz vor dem auf 8000 Jahre v.u.Z. datierten Horizont. Zu diesem Zeitpunkt war die Hudson-Meerenge von glazialem Eis ausreichend befreit, so dass sich der gegenwârtige Gezeiten-Wechsel etablieren konnte

Historical changes in thermoregulatory traits of alpine butterflies reveal complex ecological and evolutionary responses to recent climate change

Abstract Background Trait evolution and plasticity are expected to interactively influence responses to climate change, but rapid changes in and increased variability of temperature may limit evolutionary responses. We use historical specimens to document changes in the size and thermoregulatory traits of a montane butterfly, Colias meadii, in Colorado, USA over the past 60 years (1953–2012). We quantify forewing wing length, ventral wing melanin that increases solar absorption, and the length of thorax setae that reduces convective heat loss. Results The mean of all three traits has increased during this time period despite climate warming. Phenological shifts may have extended the active season earlier at low elevations and later at high elevations, increasing exposure to cool temperatures and selecting for increases in thermoregulatory traits. Fitness increases at higher elevations due to warming could also increase thermoregulatory traits. Warmer temperatures during pupal development and later flight dates in the season are associated with decreased wing melanin, indicating a role of phenotypic plasticity in historical trait changes. Conclusions Phenotypic shifts result from a complex interplay of ecological and evolutionary responses to climate change. Environmental variability within and across seasons can limit the evolutionary responses of populations to increasing mean temperatures during climate change