When Narrative Fails: Context and Physical Evidence as Means of Understanding the Northwest Boundary Survey Photographs of 1857–1862

The photographs of the Northwest Boundary Survey, taken chiefly in 1860–1861, present many of the problems commonly encountered in the study of nineteenth-century photography. These views documenting the international border between modern British Columbia and the American Pacific Northwest provide a useful case study in the close reading of physical attributes of photographs. They afford an opportunity to compare imagery and evidence across known sets, and to draw conclusions from sequencing, variant captioning, and other physical evidence. These details will help archivists and other collection managers make good decisions about depth of cataloging, digital imaging choices, and interfaces for online presentation of sets of nineteenth-century photographs

A 2022 review of sodium fluoroacetate for conservation and protecting endangered species

Sodium fluoroacetate (1080) is a vertebrate pesticide principally used to control unwanted introduced mammals in New Zealand and Australia. There have been over 260 publications during the last ten years on 1080 which supplement a body of scientific information regarding mode of action, natural occurrence, toxicology, antidotes, metabolism and fate in the environment. Multi-year studies have explored long-term outcomes, for multiple native bird species. Numerous reviews on community attitudes stimulated, in part by the Predator Free New Zealand (PFNZ) 2050 campaign, conclude that 1080 use for conservation remains controversial. Further effort is needed to increase target specificity avoiding game species and employ approaches with the highest public acceptance, including hunting, trapping and eradication strategies that obviate the need for repeated use of toxic baits. Greater acceptance of large-scale use of any pest control is likely when long-term goals and strategies for ecosystem recovery employ toxins as one-off treatments for eradicating pests versus continued applications

Sodium fluoroacetate (1080) in relation to its use in New Zealand revisited: A 2021 review

Traps, poisons and hunting are pest control tools used internationally for crop protection and to restore ecosystems, particularly on islands and continents where introduced mammals endanger native species. Sodium fluoroacetate (1080) is a vertebrate pesticide, initially developed in the 1940s, principally used to control unwanted introduced mammals in New Zealand and Australia. During the last ten years, there have been over 260 new research and review publications, specifically on 1080 in scientific journals. These publications supplement a body of scientific information regarding mode of action, natural occurrence, toxicology, including poisoning incidents and antidotes, metabolism and fate in the environment and risk to non-target species. Multi-year studies now go beyond immediate non-target impacts and explore ecosystem-level outcomes, including population-level changes for multiple native bird species following the sustained removal of predators. Numerous review publications on community attitudes to pest control and the merits of different tools and techniques have been stimulated, in part by the Predator Free NZ 2050 campaign, and these are summarised. Many sectors of our communities would prefer not to use poisons for pest control, particularly if applied aerially. If 1080 is to continue to be used in New Zealand, research still needs to focus on additional improvements in target specificity, particularly concerning the interactions of kea and game species with bait, and address any new questions raised by regulatory agencies such as the Environmental Protection Agency (EPA; formally ERMA), communities, and iwi. Additionally, there is a need to innovate how different pest control tools are used and advance close-to-market tools with the highest public acceptance, such as species-specific poisons and more targeted bait delivery or trapping systems. Community engagement should continue to be open and transparent, highlight risks and benefits, and seek consensus. In most cases, consensus will involve an integrated approach to pest control using acceptable levels of both aerial and ground-based tools. Greater acceptance of any pest control tool occurs when use is discussed within the context of long-term goals for saving endangered species and ecosystem recovery, with communities that treasure the restoration of their landscapes. However, values are changing, such that no (or minimal) pesticide use is a theme that is increasingly mainstream. In this changing environment, strategies that rely on 1080 or other toxins as one-off treatments for eradicating pests or disease versus continued application for maintenance control are likely to be more and more important

Diphacinone and cholecaliciferol (D+C) as a potent low-residue rodenticide

Rodenticides such as brodifacoum are more potent than first-generation anticoagulants. However, their field, farm, and outdoor use in urban settings have been linked to bioaccumulation and non-target impacts for more than three decades. Product development strategies focused on baits that yield good control of pests without residue risks to wildlife are few. To fill this gap, a bait containing a combination of diphacinone at 0.005% and cholecalciferol at 0.06% (D+C bait) has been developed as a multispecies bait for NZ use, that is effective at killing rodents and also possums (Trichosurus vulpecula), which are resistant to the toxin effects of first-generation anticoagulants. This bait was approved by the NZ Environmental Protection Agency and the product registered by the NZ Ministry of Primary Industries in 2019. A new bait is being considered with a lower dose of cholecalciferol. A bait containing half or a quarter of the loading concentration of cholecalciferol would have an even better safety profile for rodent control alone. Cage trials indicate that cholecalciferol at 0.03% with diphacinone 0.005% is as effective as brodifacoum as a single exposure bait. Amounts of cholecalciferol as low as 0.015% significantly improve the effectiveness of diphacinone

Developing a new resetting tool for controlling rats

A resetting toxin device (the “Spitfire”) has been designed that delivers a toxic paste to a rat’s ventral surface when it passes through a tunnel. The rat grooms off the paste and ingests the toxin. The system was assessed in cage trials and one field trial. The purpose of the cage trials was to investigate whether a range of toxins can be delivered by the Spitfire to rats (Rattus rattus and R. norvegicus), namely 0.55% sodium fluoroacetate (1080), 0.2% brodifacoum, 15% cholecalciferol, and 12.5% zinc phosphide. The trials with 1080, brodifacoum, and zinc phosphide were successful with > 85% of rats ingesting lethal doses. The trials with cholecalciferol were less successful with only 58% of rats dying. A one-month pilot field trial was undertaken using 1080 in the Spitfires. There was a knockdown in rat (and stoat Mustela erminea) abundance, establishing proof of concept for the Spitfire delivery system with this toxin. The long-term, effective control of introduced rats will require a range of toxins with different modes of action. The Spitfire could be a useful additional control tool for rats and is currently being re-engineered to be made more reliable

Phase conjugate fluorozirconate fibre laser operating at 800nm

We report phase-conjugate feedback into a fluorozirconate optical fiber amplifier at infrared wavelengths. By using a semiconductor laser diode at 807 nm, a grating is established in photorefractive BaTiO3 that, in the ring configuration, provides feedback into the amplifier necessary for laser action. Once written, the grating is self-sustaining, and lasing is observed even after the laser diode is removed

Investigation of Magnesium Cation-proton Exchange with Transmembrane Electrostatically Localized Protons (TELP) at a Liquid-membrane Interface: Fundamental to Bioenergetics

The Lee transmembrane electrostatic proton localization (TELP) theory is a revolutionary scientific theory that has successfully explained decades long-standing quandary in the field of bioenergetics in regards to ATP synthesis in biological systems, specifically alkalophilic bacteria. This study provides experimental support for the TELP theory by further demonstrating evidence of a localized proton layer existing at the liquid-membrane interface in a simulated biological membrane apparatus. Whilst monovalent cations have been studied extensively, divalent cation exchange has not been studied experimentally. A previous study determined equilibrium constant for Na+ and K+ to exchange with localized H+ layer to be (5.07 ± 0.46) x 10-8 and (6.93 ± 0.91) x 10-8 respectively. We discovered that an equilibrium exchange occurs at 0.85 mM Mg2+ concentration. The findings here contributed to the successful determination of the equilibrium constant between Mg2+ and the localized H+ layer to be (1.56 ± 0.46) x 10-5. The equilibrium constant, much smaller than one, thus provides support for Lee’s TELP model since so many more Mg2+ in the bulk liquid phase that are required to even partially delocalize just a single H+ at the liquid-membrane interface. These results are relevant to further understand how water can act as a proton conductor for proton coupling energy transduction and the implications of different biological organisms’ salinity tolerance.https://digitalcommons.odu.edu/gradposters2022_sciences/1012/thumbnail.jp

Effects of Maraviroc and Efavirenz on Markers of Immune Activation and Inflammation and Associations with CD4+ Cell Rises in HIV-Infected Patients

Maraviroc treatment for HIV-1 infected patients results in larger CD4(+) T cell rises than are attributable to its antiviral activity alone. We investigated whether this is due to modulation of T cell activation and inflammation.Thirty maraviroc-treated patients from the Maraviroc versus Efavirenz Regimens as Initial Therapy (MERIT) study were randomly selected from among those who had CCR5-tropic (R5) HIV on screening and achieved undetectable HIV RNA (<50 copies/mL) by Week 48. Efavirenz-treated controls were matched for baseline characteristics to the maraviroc-treated patients selected for this substudy. Changes in immune activation and inflammation markers were examined for associations with CD4(+) T cell changes. Maraviroc treatment tended to result in more rapid decreases in CD38 expression on CD4(+) T cells and in plasma D-dimer concentrations than did treatment with efavirenz. The proportion of patients with high-sensitivity C-reactive protein >2 µg/mL increased from 45% to 66% in the efavirenz arm, but remained constant in the maraviroc arm (P = 0.033). Decreases in CD38 expression on CD8(+) T cells were correlated with CD4(+) T cell rises for maraviroc treatment (r = -0.4, P = 0.048), but not for treatment with efavirenz.Maraviroc-treated patients had earlier, modest decreases in certain markers of immune activation and inflammation, although in this small study, many of the differences were not statistically significant. Levels of high-sensitivity C-reactive protein remained constant in the maraviroc arm and increased in the efavirenz arm. Decreases in immune activation correlated with increased CD4(+) T cell gains.ClinicalTrials.gov NCT00098293

Gain reversal studies in photorefractive waveguides

We report on low-loss photorefractive BaTiO3 H+ implanted waveguides exhibiting reversal of two-beam-coupling gain direction, caused by induced colour centres. The anomalous two-beam-coupling gain has been investigated as a function of the input beam ratio