6,368 research outputs found
Count the Outside Children! Kinkeeping as Preservation Practice Among Descendants of Texasâ Freedom Colonies
"To validate that a place exists or is worthy of listing as a significant cultural resource, it is the fundamental practice of planning and preservation professionals to establish measurable, documented facts: determining population levels, boundaries, building types, and recorded historic activities and events. Gwen Bluiett is a Jasper County resident who lives in a freedom colony called Magnolia Springs. Here, she leads a tour of a freedom colony known as Clear Creek Community. She is pointing to and recalling her time attending the church when it was active and the settlement was populated. White accounts of African American history are steeped in such enumerations. Whether it is the counting of African Americans by age, cotton production, spatial concentration, or slave auction block value, black use value has been incorporated into land-use practice and the countryâs political economy. Before and after emancipation, racialization of landscapes has overshadowed culturally relevant kinship types and forms of land ownership. Hortense Spillers describes the ambiguity in the accounting of Africans as cargo on the way to the new world disconnected from their groups of origin, gender roles, naming conventions, or the manner in which they constructed kinship ties. Captive, enumerated black people would be bundled and stacked in ship hulls, bred in plantation cabins, then cordoned off and penned into redlined zoning districts with racial covenants. Enumeration, accounting and categorization of people and places, are agents of abstraction. Because these forms of data and associated analysis are thought to be objective, questioning their underlying assumptions is discouraged. Kinkeepers disrupt this accounting approach by articulating connections between people and place as they maintain family relationships via various activities, such as planning family rituals or reunions, coordinating family caregiving, or serving as a repository of family kinship and medical information.
Precision test of a Fermion mass texture
Texture zeros in the quark Yukawa matrices generally lead to precise and simple expressions for CKM matrix elements in terms of ratios of quark masses. Using the new data on decays we test a particularly promising texture zero solution and show that it is at best approximate. We analyse the approximate texture zero structure and show it is consistent with experiment. We investigate the implications for the CKM unitarity triangle, measurements at and as well as for the theories which invoke family symmetries
Imaging of crystalline and amorphous surface regions using time-of-flight secondary-ion mass spectrometry (ToF-SIMS): application to pharmaceutical materials
The structure of a material, in particular the extremes of crystalline and amorphous forms, significantly impacts material performance in numerous sectors such as semiconductors, energy storage, and pharmaceutical products, which are investigated in this paper. To characterize the spatial distribution for crystallineâamorphous forms at the uppermost molecular surface layer, we performed time-of-flight secondary-ion mass spectroscopy (ToF-SIMS) measurements for quench-cooled amorphous and recrystallized samples of the drugs indomethacin, felodipine, and acetaminophen. Polarized light microscopy was used to localize crystallinity induced in the samples under controlled conditions. Principal component analysis was used to identify the subtle changes in the ToF-SIMS spectra indicative of the amorphous and crystalline forms for each drug. The indicators of amorphous and crystalline surfaces were common in type across the three drugs, and could be explained in general terms of crystal packing and intermolecular bonding, leading to intramolecular chain scission in the formation of secondary ions. Less intramolecular scission occurred in the amorphous form, resulting in a greater intensity of molecular and dimer secondary ions. To test the generality of amorphousâcrystalline differentiation using ToF-SIMS, a different recrystallization method was investigated where acetaminophen single crystals were recrystallized from supersaturated solutions. The findings indicated that the ability to assign the crystalline/amorphous state of the sample using ToF-SIMS was insensitive to the recrystallization method. This demonstrates ToF-SIMS capabilities of detecting and mapping ordered crystalline and disordered amorphous molecular materials forms at micron spatial resolution in the uppermost surface of a material
The Effects of Equine-Assisted Therapy on Gait in Adults with Parkinsonâs Disease: A Preliminary Analysis
Parkinsonâs disease (PD) is a chronic, progressive, neurological disorder caused by the destruction of dopamine-producing neurons in the substantia nigra of the brain. To treat motor symptoms of PD, individuals may choose alternative modes of exercise, such as equine-assisted therapy (EAT), to improve physiological health. PURPOSE: To determine changes in gait following 8 weeks of Equine Assisted Therapy (EAT) in older men with PD. METHODS: Six older adults (age = 68.0 ± 8.6 yrs; height = 178.6 ± 8.3 cm; weight = 93.4 ± 16.3 kg; Hoehn and Yahr classification = 2.8 ± 0.4; time since diagnosis = 7.3 ± 5.0 yrs) performed two, 60-minute riding sessions weekly for 8 weeks. Before, midway, immediately after, and at two points following the EAT program (at 8 weeks and 16 weeks), spatiotemporal parameters of gait were measured using motion capture with infrared markers strategically placed on lower-body anatomical landmarks. Participants walked at a self-selected speed without the use of an assistive device in the capture space for 15 consecutive strides, turned around, and walked back across the space. Gait velocity, step length, time spent in stance phase, time spent in swing phase, toe clearance were collected. Data were analyzed using a repeated-measures analysis-of-variance and a Bonferroni correction with a significance level of 0.05. RESULTS: Gait velocity (101.8 ± 29.1 vs. 109.2 ± 34.9 vs. 116.3 ± 32.8 vs. 105.7 ± 26.2 vs. 108.0 ± 25.4 cm/s for pre-EAT, midway through EAT, immediately post-EAT, 8 weeks after EAT concluded, and 16 weeks after EAT concluded, respectively) was significant across all time points (p = 0.03). All other variables were statistically similar (p \u3e 0.05) across all time points. CONCLUSION: There is an observable trend towards significance in each gait variable immediately after 8 weeks of EAT. The study is ongoing and will further explore these differences
Water-Based 3D Inkjet Printing of an Oral Pharmaceutical Dosage Form
Inkjet printing is a form of additive manufacturing where liquid droplets are selectively deposited onto a substrate followed by solidification. The process provides significant potential advantages for producing solid oral dosage forms or tablets, including a reduction in the number of manufacturing steps as well as the ability to tailor a unique dosage regime to an individual patient. This study utilises solvent inkjet printing to print tablets through the use of a Fujifilm Dimatix printer. Using polyvinylpyrrolidone and thiamine hydrochloride (a model excipient and drug, respectively), a water-based ink formulation was developed to exhibit reliable and effective jetting properties. Tablets were printed on polyethylene terephthalate films where solvent evaporation in the ambient environment was the solidification mechanism. The tablets were shown to contain a drug loading commensurate with the composition of the ink, in its preferred polymorphic phase of a non-stoichiometric hydrate distributed homogenously. The printed tablets displayed rapid drug release. This paper illustrates solvent inkjet printingâs ability to print entire free-standing tablets without an edible substrate being part of the tablet and the use of additional printing methods. Common problems with solvent-based inkjet printing, such as the use toxic solvents, are avoided. The strategy developed here for tablet manufacturing from a suitable ink is general and provides a framework for the formulation for any drug that is soluble in water
Effects of insularity on insect leaf herbivory and chemical defences in a Mediterranean oak species
Aim
Research on plantâherbivore interactions has shown that islands typically have low abundances and diversity of herbivores because of barriers to dispersal, isolation and reduced land area. Islands commonly have lower levels of herbivory relative to mainland regions, and, as a consequence, insular plants should exhibit lower levels of defences than their mainland counterparts. Despite these predictions, there are significant gaps in our understanding of insularity effects on plantâherbivore interactions. For instance, most work addressing the effects of insularity on plantâherbivore interactions have compared one or a few islands with a single mainland site. In addition, studies have measured herbivory or plant defences but not both, and the influence of abiotic factors has been neglected.
Location
Mediterranean Basin (from Spain to Greece).
Taxon
Quercus ilex L.
Methods
We conducted a largeâscale study to investigate whether insect leaf herbivory and plant chemical defences in holm oak (Quercus ilex L.) differ between insular versus mainland populations. We further investigated mechanisms by which insularity effects on herbivory may take place by assessing the influence of defences and climatic variables on herbivory.
Results
We found that insular populations exhibited lower herbivory and higher defences (condensed tannins) than their mainland counterparts. Our analyses, however, suggest that these concomitant patterns of insect herbivory and plant defences were seemingly unrelated as island versus mainland differences in defences did not account for the observed pattern in herbivory. Furthermore, climatic factors did not explain insularity effects on either herbivory or plant defences.
Main conclusions
Overall, this study provides one of the most robust assessments to date on insularity effects on herbivory and builds towards a better understanding of the ecology and evolution of plantâinsect interactions in insular ecosystems.info:eu-repo/semantics/acceptedVersio
Effects of insularity on insect leaf herbivory and chemical defences in a Mediterranean oak species
Aim
Research on plantâherbivore interactions has shown that islands typically have low abundances and diversity of herbivores because of barriers to dispersal, isolation and reduced land area. Islands commonly have lower levels of herbivory relative to mainland regions, and, as a consequence, insular plants should exhibit lower levels of defences than their mainland counterparts. Despite these predictions, there are significant gaps in our understanding of insularity effects on plantâherbivore interactions. For instance, most work addressing the effects of insularity on plantâherbivore interactions have compared one or a few islands with a single mainland site. In addition, studies have measured herbivory or plant defences but not both, and the influence of abiotic factors has been neglected.
Location
Mediterranean Basin (from Spain to Greece).
Taxon
Quercus ilex L.
Methods
We conducted a largeâscale study to investigate whether insect leaf herbivory and plant chemical defences in holm oak (Quercus ilex L.) differ between insular versus mainland populations. We further investigated mechanisms by which insularity effects on herbivory may take place by assessing the influence of defences and climatic variables on herbivory.
Results
We found that insular populations exhibited lower herbivory and higher defences (condensed tannins) than their mainland counterparts. Our analyses, however, suggest that these concomitant patterns of insect herbivory and plant defences were seemingly unrelated as island versus mainland differences in defences did not account for the observed pattern in herbivory. Furthermore, climatic factors did not explain insularity effects on either herbivory or plant defences.
Main conclusions
Overall, this study provides one of the most robust assessments to date on insularity effects on herbivory and builds towards a better understanding of the ecology and evolution of plantâinsect interactions in insular ecosystems.info:eu-repo/semantics/acceptedVersio
Rapid radiocarbon (14C) analysis of coral and carbonate samples using a continuous-flow accelerator mass spectrometry (CFAMS) system
Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 26 (2011): PA4212, doi:10.1029/2011PA002174.Radiocarbon analyses of carbonate materials provide critical information for understanding the last glacial cycle, recent climate history and paleoceanography. Methods that reduce the time and cost of radiocarbon (14C) analysis are highly desirable for large sample sets and reconnaissance type studies. We have developed a method for rapid radiocarbon analysis of carbonates using a novel continuous-flow accelerator mass spectrometry (CFAMS) system. We analyzed a suite of deep-sea coral samples and compared the results with those obtained using a conventional AMS system. Measurement uncertainty is <0.02 Fm or 160 Ryr for a modern sample and the mean background was 37,800 Ryr. Radiocarbon values were repeatable and in good agreement with those from the conventional AMS system. Sample handling and preparation is relatively simple and the method offered a significant increase in speed and cost effectiveness. We applied the method to coral samples from the Eastern Pacific Ocean to obtain an age distribution and identify samples for further analysis. This paper is intended to update the paleoceanographic community on the status of this new method and demonstrate its feasibility as a choice for rapid and affordable radiocarbon analysis.This work was performed under NSF
Cooperative Agreement OCEâ0753487, and also NSFâOPP awards 0636787
and 0944474
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