Publications by authors named "Brenda Hall"

Hamley . previously presented multiple lines of evidence that people were present in the Falkland Islands before Europeans and may have brought the now-extinct canid, . Stable isotope data reported by Clark .

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When Darwin visited the Falkland Islands in 1833, he noted the puzzling occurrence of the islands’ sole terrestrial mammal, (or “warrah”). The warrah’s origins have been debated, and prehistoric human transport was previously rejected because of a lack of evidence of pre-European human activity in the Falkland Islands. We report several lines of evidence indicating that humans were present in the Falkland Islands centuries before Europeans, including (i) an abrupt increase in fire activity, (ii) deposits of mixed marine vertebrates that predate European exploration by centuries, and (iii) a surface-find projectile point made of local quartzite.

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BACKGROUND: Delirium frequently develops in hospitalized patients and results in increased mortality, longer length of stay, and need for transitional care. Neurological patients are at an increased risk for developing delirium. There is a paucity of research on effective prevention strategies for this population.

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DC Bead is designed for the embolization of liver malignancies combined with local sustained chemotherapy delivery. It was first demonstrated around a decade ago that irinotecan could be loaded into DC Bead and used in a transarterially directed procedure to treat colorectal liver metastases, commonly referred to as drug-eluting bead with irinotecan (DEBIRI). Despite numerous reports of its safe and effective use in treating colorectal liver metastases patients, there remains a perceived fundamental paradox as to how this treatment works.

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Introduction: Mercury is a neurotoxic metal that is potentially a risk factor for amyotrophic lateral sclerosis (ALS). Consumption of methylmercury contaminated fish is the primary source of US population exposure to mercury.

Methods: We used inductively coupled plasma mass spectrometry to measure levels of mercury in toenail samples from patients with ALS (n = 46) and from controls (n = 66) as a biomarker of mercury exposure.

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Clinical use of DC Bead™ loaded with doxorubicin (DEBDOX™) or irinotecan (DEBIRI™), for the treatment of primary and secondary tumours of the liver respectively, is showing great promise. Recently there has been a tendency to select smaller bead size ranges to treat tumours in an effort to allow more drug dose to be administered, improve tumoural penetration and resultant drug delivery and tumour coverage. Herein we describe the development and performance characterisation of a new DC Bead size range (DC BeadM1 (TM), 70-150 μm) capable of an increased bead delivery in the distal vasculature, corresponding to greater tumour coverage and drug dose delivered.

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The Younger Dryas Stadial (YDS; ∼ 12,900-11,600 y ago) in the Northern Hemisphere is classically defined by abrupt cooling and renewed glaciation during the last glacial-interglacial transition. Although this event involved a global reorganization of atmospheric and oceanic circulation [Denton GH, Alley RB, Comer GC, Broecker WS (2005) Quat Sci Rev 24:1159-1182], the magnitude, seasonality, and geographical footprint of YDS cooling remain unresolved and pose a challenge to our understanding of abrupt climate change. Here, we present a deglacial chronology from Scotland, immediately downwind of the North Atlantic Ocean, indicating that the Scottish ice cap disintegrated during the first half of the YDS.

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Genetic diversity provides the raw material for populations to respond to changing environmental conditions. The evolution of diversity within populations is based on the accumulation of mutations and their retention or loss through selection and genetic drift, while migration can also introduce new variation. However, the extent to which population growth and sustained large population size can lead to rapid and significant increases in diversity has not been widely investigated.

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Article Synopsis
  • Ethylene perception in Arabidopsis is mediated by a family of five receptors, with subfamily 1 members having histidine kinase activity while subfamily 2 members do not.
  • Transformations of a mutant plant with both wild-type and kinase-inactive versions of ETR1 show that while both versions restore normal growth, the kinase-inactive version leads to reduced ethylene sensitivity.
  • Analysis suggests that the histidine kinase activity of ETR1 is not essential for ethylene responses, but it does play a significant role in modulating these responses, impacting related protein levels.
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The McMurdo Dry Valleys in Antarctica are a favorable location for preservation of dormant microbes due to their persistent cold and dry climate. In this study, we examined cultivable bacteria in a series of algal mat samples ranging from 8 to 26539 years old. Cultivable bacteria were found in all samples except one (12303 years old), but abundance and diversity of cultivable bacteria decreased with increasing sample age.

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The phasing of millennial-scale oscillations in Antarctica relative to those elsewhere in the world is important for discriminating among models for abrupt climate change, particularly those involving the Southern Ocean. However, records of millennial-scale variability from Antarctica dating to the last glacial maximum are rare and rely heavily on data from widely spaced ice cores, some of which show little variability through that time. Here, we present new data from closed-basin lakes in the Dry Valleys region of East Antarctica that show high-magnitude, high-frequency oscillations in surface level during the late Pleistocene synchronous with climate fluctuations elsewhere in the Southern Hemisphere.

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Environmental change drives demographic and evolutionary processes that determine diversity within and among species. Tracking these processes during periods of change reveals mechanisms for the establishment of populations and provides predictive data on response to potential future impacts, including those caused by anthropogenic climate change. Here we show how a highly mobile marine species responded to the gain and loss of new breeding habitat.

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The purpose of this study was to assess the safety and efficacy of doxorubicin-loaded beads (DC Beads) delivered by transarterial embolization for the treatment of unresectable hepatocellular carcinoma (HCC). This open-label, single-center, single-arm study included 62 cirrhotic patients with documented single unresectable HCC. Mean tumor diameter was 5.

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Purpose: To examine the results of segmental transcatheter arterial chemoembolization with doxorubicin-loaded DC Bead in the treatment of hepatocellular carcinoma (HCC) in non-surgical candidates.

Material And Methods: Seventy-one patients (60% men; 11% women; mean age 63; range 46-71 years) with documented HCC of 3-10 cm in diameter (mean 6.2) were enrolled prospectively in the study.

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DC Bead is a sulfonate-modified, PVA-based microspherical embolisation agent approved for the treatment of hypervascular tumours and arterio-venous malformations. The beads have previously been shown to actively sequester oppositely charged drugs, such as doxorubicin hydrochloride (dox) by an ion-exchange mechanism. In order to characterise the release kinetics and predict the in vivo behaviour of drug eluting beads (DEB), two elution methods were utilised.

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Background: The ethylene receptor family of Arabidopsis consists of five members, falling into two subfamilies. Subfamily 1 is composed of ETR1 and ERS1, and subfamily 2 is composed of ETR2, ERS2, and EIN4. Although mutations have been isolated in the genes encoding all five family members, the only previous insertion allele of ERS1 (ers1-2) is a partial loss-of-function mutation based on our analysis.

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Purpose: To present the pathologic and pharmacokinetic findings from hepatic embolization in a porcine model comparing doxorubicin-eluting beads with bland embolization and to correlate these findings with in vitro release kinetics.

Materials And Methods: Drug-eluting beads (DEB; 100-300 microm and 700-900 microm) loaded with 37.5 mg doxorubicin per milliliter hydrated beads were used to embolize the hepatic artery feeding the left lobe of the liver in young adult Yucatan pigs (n = 5 per group).

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Purpose: The purpose of this investigation is to present the in vitro characterization and detailed drug-loading procedure for DC Bead, a microsphere product that can be loaded with chemotherapeutic agents for embolization.

Materials And Methods: DC Bead is an embolic microsphere product that is capable of being loaded with anthracycline drugs such as doxorubicin just before administration in a transarterial chemoembolization (TACE) procedure. Beads can be loaded from solutions prepared from doxorubicin powder or the doxorubicin HCl formulation.

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Parents are actively involved in the direct care of their ill child receiving cancer treatment by providing and monitoring therapy and by managing symptoms related to the therapy or to the disease itself. Little is known about parents' perception of what helps or hinders them with their caregiving responsibilities or what effect the caregiving role has on the parent. In this descriptive, exploratory study, 151 parents responded to one or more of six open-ended questions that were part of the newly developed instrument, Care of My Child with Cancer.

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The growing societal trend toward delivering more and more illness-related care in the home, driven both by family preferences and by mandates from third-party reimbursers, places additional responsibilities for increasingly complex caregiving on parents of children with serious illness. This article reports on the development and initial field test of The Care of My Child with Cancer, a caregiving demand instrument specific to the childhood cancer population. The instrument demonstrated strong internal consistency and test-retest reliability, and exploratory factor analysis provided initial evidence for the instrument's construct validity.

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