Dynamics of Vortex Core Switching in Ferromagnetic Nanodisks

Dynamics of magnetic vortex core switching in nanometer-scale permalloy disk, having a single vortex ground state, was investigated by micromagnetic modeling. When an in-plane magnetic field pulse with an appropriate strength and duration is applied to the vortex structure, additional two vortices, i.e., a circular- and an anti-vortex, are created near the original vortex core. Sequentially, the vortex-antivortex pair annihilates. A spin wave is created at the annihilation point and propagated through the entire element; the relaxed state for the system is the single vortex state with a switched vortex core.Comment: to appear in Appl. Phys. Let

Dancing with scalps: native North American women, white men and ritual violence in the eighteenth century

Native American women played a key role in negotiating relations between settler and Native society, especially through their relationships with white men. Yet they have traditionally languished on the sidelines of Native American and colonial American history, often viewed as subordinate and thus tangential to the key themes of these histories. This dissertation redresses the imbalance by locating women at the centre of a narrative that has been dominated by discourses in masculine aspirations. It explores the variety of relations that developed between men and women of two frontier societies in eighteenth century North America: the Creeks of the Southeast, and the Mi’kmaq of Nova Scotia. This dissertation complicates existing histories of Native and colonial America by providing a study of Indian culture that, in a reversal of traditional inquiry, asks how Native women categorised and incorporated white people into their physical and spiritual worlds. One method was through ritualised violence and torture of captives. As primary agents of this process women often selected, rejected or adopted men into the tribes, depending on factors that ranged from nationality to religion. Such acts challenged contemporary Euro-American wisdom that ordained a nurturing, auxiliary role for women. However, this thesis shows that ‘anomalous’ violent behaviours of Indian women were rooted in a femininity inculcated from an early age. In this volatile world, women were not shielded from the horrors of war. Instead, they became one of those horrors. Therefore, viewing anomalous actions as central to the analysis provides an understanding of female identities outwith the straitjacket of the Euro-American gender binary. With violence as a legitimate and natural expression of feminine power, the Indian woman’s character was far removed from depictions of the sexualised exotic, self-sacrificing Pocahontas or stoic Sacagawea. The focus on women’s violent customs, which embodied several important and unusual manifestations of Native American femininity, reveals a number of jarring behaviours that have found no home within colonial literatures. These behaviours included sanctioned infanticide and abortions, brutal tests for adolescents, scalp dancing and death rites, cannibalism, mercenary wives and sadistic grandmothers. With limited means of incorporating such female characteristics into pre-existing gender categories, the women’s acts were historically treated as non-representative of regular Indian lifeways and thus dismissed. Colonial relations are therefore analysed through an alternative lens to accommodate these acts. This allows women to construct their own narrative in a volatile landscape that largely sought to exclude those voices, voices that challenged dominant ideologies on appropriate male-female relations. By constructing a new gender framework I show that violence was a vehicle by which women realised, promoted and reinforced their tribal standing

In Vitro Maturation of a Humanized Shark VNAR Domain to Improve Its Biophysical Properties to Facilitate Clinical Development

Acknowledgments: The authors would like to acknowledge the funding support for this work from Scottish Enterprise [VNAR_001(2012)] and the Biotechnology and Biological Sciences Research Council (BB/K010905/1).Peer reviewedPublisher PD

Pressure Tuning of the Charge Density Wave in the Halogen-Bridged Transition-Metal (MX) Solid Pt2Br6(NH3)4Pt_2Br_6(NH_3)_4

We report the pressure dependence up to 95 kbar of Raman active stretching modes in the quasi-one-dimensional MX chain solid $Pt_2Br_6(NH_3)_4$. The data indicate that a predicted pressure-induced insulator-to-metal transition does not occur, but are consistent with the solid undergoing either a three-dimensional structural distortion, or a transition from a charge-density wave to another broken-symmetry ground state. We show that such a transition cacan be well-modeled within a Peierls-Hubbard Hamiltonian. 1993 PACS: 71.30.+h, 71.45.Lr, 75.30.Fv, 78.30.-j, 81.40.VwComment: 4 pages, ReVTeX 3.0, figures available from the authors on request (Gary Kanner, [email protected]), to be published in Phys Rev B Rapid Commun, REVISION: minor typos corrected, LA-UR-94-246

The impact of Nutrition and Gastrointestinal Symptoms on Health-related Quality of Life in Survivorship after Oesophageal Cancer Surgery

Summary Background and Aims Oesophagectomy is the primary curative treatment for oesophageal cancer but is associated with considerable postoperative morbidity and mortality. To better understand the aetiology of impaired health-related quality of life (HRQL) in oesophageal cancer survivors (OCS), this study sought to determine the longitudinal changes in nutritional status, nutrition-impact symptoms (NIS), and HRQL in this cohort, and to determine which variables have the greatest impact on postoperative HRQL decline. Methods Data, derived from St. James\u27 Hospital, Dublin, included patients who underwent oesophagectomy from October 2017 to May 2019 and attended clinic preoperatively and 6 months postoperatively. A subset attended a further 12-month appointment. HRQL and symptom data were collected using validated questionnaires and anthropometric measures were completed by clinicians. Data were analysed using SPSS. Results A total of 66 patients were studied preoperatively and 6 months postoperatively, of whom 37 were studied at 12 months postoperatively. Malnutrition remained prevalent at each time-point, although rates did not significantly change longitudinally. Conversely, the prevalence of malabsorption (7.6%–14.3%, P\u3c0.001) and dumping syndrome (67.7%–74.3%, P=0.003) significantly increased with increasing time postoperatively. NIS were significantly associated with impaired HRQL function scores and were independent predictors of global quality of life (gQOL) score postoperatively (P=0.004). A diagnostic threshold of gastrointestinal symptom severity (11.5) that identifies patients at risk of impaired gQOL was therefore reported. Conclusion Malnutrition and NIS are prevalent post-oesophagectomy, the latter significantly associated with reduced HRQL. Targeted intervention in those with severe NIS could be highly beneficial, highlighting the need for dietetic input in OCS

Interaction of Gold Nanoparticles in Barium Titanate Thin Films

A novel approach to control the grain size of oxide thin film materials has been investigated. Perovskite BaTiO3 shows interesting grain structures when deposited on gold predeposited, (111)-oriented, singlecrystal SrTiO3 substrates. Solid oxide films grow epitaxially on patterned seed layers and show variations in grain size relative to the films deposited on SrTiO3 directly.Comment: 14 pages, 4 figure

Concurrent regulation of LKB1 and CaMKK2 in the activation of AMPK in castrate-resistant prostate cancer by a well-defined polyherbal mixture with anticancer properties

Abstract Background Zyflamend, a blend of herbal extracts, effectively inhibits tumor growth using preclinical models of castrate-resistant prostate cancer mediated in part by 5′-adenosine monophosphate-activated protein kinase (AMPK), a master energy sensor of the cell. Clinically, treatment with Zyflamend and/or metformin (activators of AMPK) had benefits in castrate-resistant prostate cancer patients who no longer responded to treatment. Two predominant upstream kinases are known to activate AMPK: liver kinase B1 (LKB1), a tumor suppressor, and calcium-calmodulin kinase kinase-2 (CaMKK2), a tumor promotor over-expressed in many cancers. The objective was to interrogate how Zyflamend activates AMPK by determining the roles of LKB1 and CaMKK2. Methods AMPK activation was determined in CWR22Rv1 cells treated with a variety of inhibitors of LKB1 and CaMKK2 in the presence and absence of Zyflamend, and in LKB1-null HeLa cells that constitutively express CaMKK2, following transfection with wild type LKB1 or catalytically-dead mutants. Upstream regulation by Zyflamend of LKB1 and CaMKK2 was investigated targeting protein kinase C-zeta (PKCζ) and death-associated protein kinase (DAPK), respectively. Results Zyflamend’s activation of AMPK appears to be LKB1 dependent, while simultaneously inhibiting CaMKK2 activity. Zyflamend failed to rescue the activation of AMPK in the presence of pharmacological and molecular inhibitors of LKB1, an effect not observed in the presence of inhibitors of CaMKK2. Using LKB1-null and catalytically-dead LKB1-transfected HeLa cells that constitutively express CaMKK2, ionomycin (activator of CaMKK2) increased phosphorylation of AMPK, but Zyflamend only had an effect in cells transfected with wild type LKB1. Zyflamend appears to inhibit CaMKK2 by DAPK-mediated phosphorylation of CaMKK2 at Ser511, an effect prevented by a DAPK inhibitor. Alternatively, Zyflamend mediates LKB1 activation via increased phosphorylation of PKCζ, where it induced translocation of PKCζ and LKB1 to their respective active compartments in HeLa cells following treatment. Altering the catalytic activity of LKB1 did not alter this translocation. Discussion Zyflamend’s activation of AMPK is mediated by LKB1, possibly via PKCζ, but independent of CaMKK2 by a mechanism that appears to involve DAPK. Conclusions Therefore, this is the first evidence that natural products simultaneously and antithetically regulate upstream kinases, known to be involved in cancer, via the activation of AMPK.https://deepblue.lib.umich.edu/bitstream/2027.42/144515/1/12906_2018_Article_2255.pd

ZNF804A risk allele is associated with relatively intact gray matter volume in patients with schizophrenia

ZNF804A rs1344706 is the first genetic risk variant to achieve genome wide significance for psychosis. Following earlier evidence that patients carrying the ZNF804A risk allele had relatively spared memory function compared to patient non-carriers, we investigated whether ZNF804A was also associated with variation in brain volume. In a sample of 70 patients and 38 healthy participants we used voxel based morphometry to compare homozygous (AA) carriers of the ZNF804A risk allele to heterozygous and homozygous (AC/CC) non-carriers for both whole brain volume and specific regions implicated in earlier ZNF804A studies-the dorsolateral pre-frontal cortex, the hippocampus, and the amygdala. For patients, but not for controls, we found that homozygous 'AA' risk carriers had relatively larger gray matter volumes than heterozygous/homozygous non-carriers (AC/CC), particularly for hippocampal volumes. These data are consistent with our earlier behavioral data and suggest that ZNF804A is delineating a schizophrenia subtype characterized by relatively intact brain volume. Establishing if this represents a discrete molecular pathogenesis with consequences for nosology and treatment will be an important next step in understanding ZNF084A's role in illness risk

Investigations of biomimetic light energy harvesting pigments

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Nature uses chlorophyll and other porphyrinic pigments to capture and transfer light energy as a preliminary step in photosynthesis. The design of synthetic assemblies of light harvesting and energy directing pigments has been explored through synthesis and characterization of porphyrin oligomers. In this project, pigment electronic and vibrational structures have been explored by electrochemistry and dynamic and static optical measurements. Transient absorption data reveal energy transfer between pigments with lifetimes on the order of 20--200 picoseconds, while Raman data reveal that the basic porphyrin core structure is unperturbed relative to the individual monomer units. These two findings, along with an extensive series of experiments on the oxidized oligomers, reveal that coupling between the pigments is fundamentally weak, but sufficient to allow facile energy transfer as the predominant excited state process. Modeling of the expected quantum yields for energy transfer within a variety of arrays was accomplished, thereby providing a tool to guide synthetic goals