144 research outputs found
Ancient art and the eighteenth‐century auction: Collecting, catalogues and competition
This article explores the role of the auction in the formation and dispersal of collections of ancient art in late eighteenth- and early nineteenth-century Britain. I demonstrate that competitive collecting, as well as the culture of acquiring as well as fragmenting collections at auction, had a profound effect on the way in which British buyers collected and displayed antiquities within their private collections. I argue that through an exploration of two textual sites, the auction and collection catalogue, we can observe that collectors carefully curated their collections, visually as well as textually, in order to craft specific narratives centered on the act of auction collecting, shaping and shifting the ways in which collectors understood and curated the art of antiquity
The presence, speciation, and movement of arsenic in Lake Tarawera
Arsenic is a naturally occurring element with potential toxicity to humans depending on concentration and chemical state. Contamination of freshwater environments by arsenic has been seen globally, occurring through both natural and anthropogenic sources. This thesis explores the presence, speciation, and movement of arsenic within Lake Tarawera, including the related physical and biogeochemical processes that control the movement and state of arsenic within the water body and from inlet sources.
Lake Tarawera, in the Bay of Plenty Region, North Island, New Zealand is a large deep-water lake in an active volcanic region. Field measurements taken from Lake Tarawera were targeted towards a known localised geothermal area to explore spatial heterogeneity. The results show how the monomictic cycling regime of Lake Tarawera contributes to the retention of arsenic in the water column through increasing concentrations of benthic arsenic during the period of stratification across five open-water sites (196% difference between surface and benthic water As concentrations in March 2020), and homogenous distribution through winter overturning (10% maximum difference in As concentrations, statistically insignificant). The physical and chemical conditions of the lake (temperature and pH) and high solubility of arsenic retain dissolved species in the water column. Oxygen depletion is observed in the deepest part of the lake (2.3 mg L⁻¹ at 79 m depth) which corresponds with increased benthic arsenic concentrations (126 µg L⁻¹).
Inlets in the southern arm of the lake (Wairua Arm) are higher sources of arsenic into the water body than inlets in the main body of the lake, with arsenic concentrations from all sampled Wairua Arm inlets exceeding the World Heath Organisation 10 µg L⁻¹ drinking water standard; dissolved concentrations ranging from 41.0-947 µg L⁻¹. One high volume waterfall (Rotomahana WateArsenic is a naturally occurring element with potential toxicity to humans depending on concentration and chemical state. Contamination of freshwater environments by arsenic has been seen globally, occurring through both natural and anthropogenic sources. This thesis explores the presence, speciation, and movement of arsenic within Lake Tarawera, including the related physical and biogeochemical processes that control the movement and state of arsenic within the water body and from inlet sources. Lake Tarawera, in the Bay of Plenty Region, North Island, New Zealand is a large deep-water lake in an active volcanic region. Field measurements taken from Lake Tarawera were targeted towards a known localised geothermal area to explore spatial heterogeneity. The results show how the monomictic cycling regime of Lake Tarawera contributes to the retention of arsenic in the water column through increasing concentrations of benthic arsenic during the period of stratification across five open-water sites (196% difference between surface and benthic water As concentrations in March 2020), and homogenous distribution through winter overturning (10% maximum difference in As concentrations, statistically insignificant). The physical and chemical conditions of the lake (temperature and pH) and high solubility of arsenic retain dissolved species in the water column. Oxygen depletion is observed in the deepest part of the lake (2.3 mg L⁻¹ at 79 m depth) which corresponds with increased benthic arsenic concentrations (126 µg L⁻¹). Inlets in the southern arm of the lake (Wairua Arm) are higher sources of arsenic into the water body than inlets in the main body of the lake, with arsenic concentrations from all sampled Wairua Arm inlets exceeding the World Heath Organisation 10 µg L⁻¹ drinking water standard; dissolved concentrations ranging from 41.0-947 µg L⁻¹. One high volume waterfall (Rotomahana Waterfall) provides a per second arsenic loading of 16,400 ± 2,660 µg As s⁻¹. The more toxic form of arsenic (AsIII) was only detected in one instance, from a warm water stream inlet. Iron and manganese concentrations and the partitioning of these transition metals indicates the ratio of arsenic to these binding elements is not of the right order of magnitude to remove substantial arsenic from the water column, as dissolved arsenic concentrations exceed that of both iron and manganese.
Water isotope ratios and dissolved arsenic concentrations from Rotomahana Waterfall show a complicated mixing regime, including influences such as wind, rainfall, other inlets, and opposing water flows coming from the main water and the high flow waterfall. High temperature and low flow waters from Hot Water Beach demonstrates the influence of inlet water temperature because they alter the movement and concentrations of arsenic heading out towards the open-water inlets. The high temperature of Hot Water Beach creates a localised area of thermal stratification, which causes surface mixing and dilution of the inlet waters with the nearest open-water site. Mixing then occurs with depth closer to the open-water site, passed the point of the hot water induced thermocline. These targeted samples highlight how well arsenic is diluted and buffered by such a large volume of water, and demonstrate the importance of stratification, temperature, and flow rate on the movement of As.
Laboratory and field studies attempted to minimise oxygen introduction to pore water samples using rhizons (pore water filters) and vacutainers. Arsenic speciation was retained in field samples in the vacutainers for up to three months, with concentrations of up to 2,230 µg L-1 of AsIII measured; this result which led to laboratory experiments on the long-term storage and retention of AsIII. However, the data from these laboratory studies were inconclusive for over-time analyses of two experiments; days 2, 26, and 55 after sample spiking for the first experiment, and days 2 and 29 for the second experiment. Vacutainers and rhizons extracted pore waters in-situ in attempt to minimise oxygen introduction to low dissolved oxygen samples; however, the methodology for long-term storage requires further research.
Speciation of arsenic occurs in the sediments due to the highly anoxic environment, with pore water AsIII concentrations ranging exceeding 2,000 µg L⁻¹ in the surface sediments and decreasing with depth. Sediment concentrations show distinct accumulation boundaries which are indicative of redox boundaries over time. rfall) provides a per second arsenic loading of 16,400 ± 2,660 µg As s⁻¹. The more toxic form of arsenic (AsIII) was only detected in one instance, from a warm water stream inlet. Iron and manganese concentrations and the partitioning of these transition metals indicates the ratio of arsenic to these binding elements is not of the right order of magnitude to remove substantial arsenic from the water column, as dissolved arsenic concentrations exceed that of both iron and manganese. Water isotope ratios and dissolved arsenic concentrations from Rotomahana Waterfall show a complicated mixing regime, including influences such as wind, rainfall, other inlets, and opposing water flows coming from the main water and the high flow waterfall. High temperature and low flow waters from Hot Water Beach demonstrates the influence of inlet water temperature because they alter the movement and concentrations of arsenic heading out towards the open-water inlets. The high temperature of Hot Water Beach creates a localised area of thermal stratification, which causes surface mixing and dilution of the inlet waters with the nearest open-water site. Mixing then occurs with depth closer to the open-water site, passed the point of the hot water induced thermocline. These targeted samples highlight how well arsenic is diluted and buffered by such a large volume of water, and demonstrate the importance of stratification, temperature, and flow rate on the movement of As. Laboratory and field studies attempted to minimise oxygen introduction to pore water samples using rhizons (pore water filters) and vacutainers. Arsenic speciation was retained in field samples in the vacutainers for up to three months, with concentrations of up to 2,230 µg L⁻¹ of AsIII measured; this result which led to laboratory experiments on the long-term storage and retention of AsIII. However, the data from these laboratory studies were inconclusive for over-time analyses of two experiments; days 2, 26, and 55 after sample spiking for the first experiment, and days 2 and 29 for the second experiment. Vacutainers and rhizons extracted pore waters in-situ in attempt to minimise oxygen introduction to low dissolved oxygen samples; however, the methodology for long-term storage requires further research. Speciation of arsenic occurs in the sediments due to the highly anoxic environment, with pore water AsIII concentrations ranging exceeding 2,000 µg L⁻¹ in the surface sediments and decreasing with depth. Sediment concentrations show distinct accumulation boundaries which are indicative of redox boundaries over time
Loss of miR-200c: A Marker of Aggressiveness and Chemoresistance in Female Reproductive Cancers
We focus on unique roles of miR-200c in breast, ovarian, and endometrial cancers. Members of the miR-200 family target ZEB1, a transcription factor which represses E-cadherin and other genes involved in polarity. We demonstrate that the double negative feedback loop between miR-200c and ZEB1 is functional in some, but not all cell lines. Restoration of miR-200c to aggressive cancer cells causes a decrease in migration and invasion. These effects are independent of E-cadherin status. Additionally, we observe that restoration of miR-200c to ovarian cancer cells causes a decrease in adhesion to laminin. We have previously reported that reintroduction of miR-200c to aggressive cells that lack miR-200c expression restores sensitivity to paclitaxel. We now prove that this ability is a result of direct targeting of class III beta-tubulin (TUBB3). Introduction of a TUBB3 expression construct lacking the miR-200c target site into cells transfected with miR-200c mimic results in no change in sensitivity to paclitaxel. Lastly, we observe a decrease in proliferation in cells transfected with miR-200c mimic, and cells where ZEB1 is knocked down stably, demonstrating that the ability of miR-200c to enhance sensitivity to paclitaxel is not due to an increased proliferation rate
Improving Case Plans and Interventions for Adolescents on Probation: The Implementation of the SAVRY and a Structured Case Planning Form
Even when probation officers use risk assessment tools, many of their clients’ needs remain unaddressed. As such, we examined whether the implementation of the Structured Assessment of Violence Risk in Youth (SAVRY) and a structured case planning form resulted in better case plans as compared to prior practices (i.e., a non-validated local tool and an unstructured plan). Our sample comprised 216 adolescents on probation who were matched via propensity scores. Adolescents in the SAVRY/Structured Plan condition had significantly better case plans than those in the pre-implementation condition. Specifically, following implementation, adolescents’ high need domains were more likely to be targeted in plans. Plans also scored higher on other quality indicators (e.g., level of detail). These improvements appeared to be due primarily to the structured plan rather than the SAVRY. Overall, our findings highlight that, just as structure can improve risk assessments, so too might structure improve case plans
Predictive Validity of the SAVRY With Indigenous and Caucasian Female and Male Adolescents on Probation
Indigenous people and the courts have emphasized that it is important to examine whether violence risk assessment tools are valid and appropriate for Indigenous youth. However, studies are scarce. Therefore, we examined the predictive validity of youth probation officers’ SAVRY ratings for 744 Canadian youth, including 299 Indigenous youth (219 male, 80 female), and 445 Caucasian youth (357 male, 88 female) in a prospective field study. The SAVRY summary risk ratings and risk total scores significantly predicted violent and any reoffending for Indigenous female and male youth with medium effect sizes. Relatively few significant differences in the predictive validity emerged for Indigenous and Caucasian youth. However, Historical, Protective, and Risk Total scores predicted any recidivism better for Caucasian males than Indigenous males. Also, Indigenous youth scored significantly higher on all risk domains than Caucasian youth. Opposite to predictions, the rates of false positives were higher for Caucasian youth than for Indigenous youth. Based on the results, the SAVRY appears to be a reasonable tool to use for assessing risk in youth who are Indigenous. However, assessors should take steps to ensure that they use the SAVRY in a culturally appropriate manner, such as considering cultural factors in case formulations and treatment planning as the SAVRY does not ground assessments in an understanding of factors such as colonialism. In addition, future research should examine culturally salient risk factors (e.g., discrimination) and examine potential causes of higher risk scores in Indigenous youth, particularly the role of both past and present-day colonialism
Effects of water management and cultivar on carbon dynamics, plant productivity and biomass allocation in European rice systems
We thank the researchers at CREA-Centro di ricerca cerealicoltura e colture industriali, Vercelli, for allowing us to use their facilities, and the technical staff for their assistance. This research was conducted in the framework of the FACCE-JPI project GreenRice (Sustainable and environmental friendly rice cultivation systems in Europe) and was supported by the Biotechnology and Biological Sciences Research Council (BBSRC) BB/M018415/1.Peer reviewedPublisher PD
Adoption of online customer reviews : the influence of central and peripheral route factors
Abstract: The purpose of this study was to examine the influence of the central route factor of argument quality and the peripheral route factor of perceived source credibility on adoption of online customer reviews of guesthouses. The study made use of a descriptive research design. Data was collected from 306 respondents in Gauteng using a structured questionnaire. The study uncovered that both argument quality and source credibility have a significant influence on perceived information usefulness which in turn exerts positive influence on adoption of online reviews. The findings showed that source credibility had a stronger influence on perceived information usefulness than argument quality. The implications for management of guesthouse establishments include the need for them to understand the importance of high quality online reviews in persuading consumers to choose a guesthouse. Managers can encourage their customers to post their guesthouse experiences online and to do so in a comprehensive manner by covering varied aspects of the service
Multiple environmental benefits of alternate wetting and drying irrigation system with limited yield impact on European rice cultivation : the Ebre Delta case
Acknowledgements This research was supported by the FACCE-JPI NET project GreenRice (Sustainable and environmentally friendly rice cultivation systems in Europe, ref. 618105), which for M.M-E and M.C-F. was awarded through the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA); and for AHP, YAT, VO and NC was awarded through BBSRC grant BB/M018415/1. The support of the CERCA Programme / Generalitat de Catalunya is also acknowledged. The authors also wish to thank Dr. Esperança Gacia (Blanes Centre for Advanced Studies - Higher Council of Scientific Investigations -CEAB-CSIC) for her revision of the manuscript prior to submission. The authors would like to thank Lluís Jornet, Pep Cabanes and David Mateu (IRTA-Marine and continental waters) and, Oriol Navarro (IRTA- Extensive crops) for their technical assistance in field.Peer reviewedPostprin
Differential effects of hnRNP D/AUF1 isoforms on HIV-1 gene expression
Control of RNA processing plays a major role in HIV-1 gene expression. To explore the role of several hnRNP proteins in this process, we carried out a siRNA screen to examine the effect of depletion of hnRNPs A1, A2, D, H, I and K on HIV-1 gene expression. While loss of hnRNPs H, I or K had little effect, depletion of A1 and A2 increased expression of viral structural proteins. In contrast, reduced hnRNP D expression decreased synthesis of HIV-1 Gag and Env. Loss of hnRNP D induced no changes in viral RNA abundance but reduced the accumulation of HIV-1 unspliced and singly spliced RNAs in the cytoplasm. Subsequent analyses determined that hnRNP D underwent relocalization to the cytoplasm upon HIV-1 infection and was associated with Gag protein. Screening of the four isoforms of hnRNP D determined that, upon overexpression, they had differential effects on HIV-1 Gag expression, p45 and p42 isoforms increased viral Gag synthesis while p40 and p37 suppressed it. The differential effect of hnRNP D isoforms on HIV-1 expression suggests that their relative abundance could contribute to the permissiveness of cell types to replicate the virus, a hypothesis subsequently confirmed by selective depletion of p45 and p42
Accelerating surveillance and research of antimicrobial resistance - an online repository for sharing of antimicrobial susceptibility data associated with whole-genome sequences
Antimicrobial resistance (AMR) is an emerging threat to modern medicine. Improved diagnostics and surveillance of resistant bacteria require the development of next-generation analysis tools and collabor
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