Automated, objective texture segmentation of multibeam echosounder data - Seafloor survey and substrate maps from James Island to Ozette Lake, Washington Outer Coast

Without knowledge of basic seafloor characteristics, the ability to address any number of critical marine and/or coastal management issues is diminished. For example, management and conservation of essential fish habitat (EFH), a requirement mandated by federally guided fishery management plans (FMPs), requires among other things a description of habitats for federally managed species. Although the list of attributes important to habitat are numerous, the ability to efficiently and effectively describe many, and especially at the scales required, does not exist with the tools currently available. However, several characteristics of seafloor morphology are readily obtainable at multiple scales and can serve as useful descriptors of habitat. Recent advancements in acoustic technology, such as multibeam echosounding (MBES), can provide remote indication of surficial sediment properties such as texture, hardness, or roughness, and further permit highly detailed renderings of seafloor morphology. With acoustic-based surveys providing a relatively efficient method for data acquisition, there exists a need for efficient and reproducible automated segmentation routines to process the data. Using MBES data collected by the Olympic Coast National Marine Sanctuary (OCNMS), and through a contracted seafloor survey, we expanded on the techniques of Cutter et al. (2003) to describe an objective repeatable process that uses parameterized local Fourier histogram (LFH) texture features to automate segmentation of surficial sediments from acoustic imagery using a maximum likelihood decision rule. Sonar signatures and classification performance were evaluated using video imagery obtained from a towed camera sled. Segmented raster images were converted to polygon features and attributed using a hierarchical deep-water marine benthic classification scheme (Greene et al. 1999) for use in a geographical information system (GIS). (PDF contains 41 pages.

Mothering on Maple Avenue: An Exploration of African American Women’s Agency in Nineteenth Century Germantown, New York

National discourse on womanhood and mothering in nineteenth century America positioned these fields of women’s practices as sites of privilege for middle-class Anglo-American women, and as inaccessible to their African American contemporaries. After gaining their nominal freedom through New York’s manumission of enslaved individual around 1830, African American families had to confront their new reality to find ways to articulate their position within American society. How then, did the African American women of the Persons family, who occupied the Maple Avenue Parsonage in Germantown, New York during the nineteenth century, confront this new reality? What position within society did they see themselves as inhabiting? And lastly, by what means of agency did they inhabit this position? By employing John Barrett’s archaeology of inhabitation, this study aims to complexly situate material remains recovered from the Parsonage back within the historical context that produced these material conditions, and which act as both medium and by-product of the Persons’ actions. This approach to material analysis reveals that the Persons’ agentic actions actively transform the structural conditions of nineteenth century America, to articulate an African American approach to womanhood and motherhood that hints at values origination outside of American society. This conclusion directly argues against studies which aim to homogenize African American experiences after emancipation

The crystal growth and properties op some chalcogenides of zinc and cadmium

The main purpose of the work described in this thesis was to develop techniques for producing boules of ZnSe and ZnS(_x)Se(_1-x) suitable for research purposes. This was accomplished by extending the method that Clark and Woods((^1)) used for CdS to the higher temperatures needed to grow ZnS and ZnS(_x)Se(_1-x) in the range x = 0-0.6. In this system the capsule is connected to a reservoir of one of the components via a narrow orifice to maintain constant growth conditions. The system has been examined theoretically in an attempt to learn more about the actual conditions of growth within the capsule. It was concluded that growth occurs close to stoichiometry with(the ratio of P(_se2)/P(_zn) at the growth face) approximately 0.194 or 1.12 according to the element in the reservoir. Particular emphasis was placed upon the incorporation of manganese into the zinc selenide lattice. Concentrations of the order 300 p.p.m. were obtained when the element was added to the charge and MnCl(_2) was placed in the reservoir. Higher levels of manganese (~1%) were obtained using chemical vapour transport with iodine as the transport agent. Boules of solid solutions, within the range of compositions from ZnSe to ZnSe(_0.4)S(_0.6) were examined using a transmission electron microscope. The dominant crystallographic defects were found to change from thin twins to stacking faults as the amount of ZnS was increased. The origin of the defects was probably post growth stress. Finally, the anomalous photovoltaic effect was discovered in ZnSe needle crystals, and was explained qualitatively in terms of asymmetrical barriers along the polar axis of the crystal

Using practice effects for targeted trials or sub-group analysis in Alzheimer\u27s disease: How practice effects predict change over time

OBJECTIVE: To describe the presence of practice effects in persons with Alzheimer disease (AD) or mild cognitive impairment (MCI) and to evaluate how practice effects affect cognitive progression and the outcome of clinical trials. METHODS: Using data from a meta-database consisting of 18 studies including participants from the Alzheimer disease Cooperative Study (ADCS) and the Alzheimer Disease Neuroimaging Initiative (ADNI) with ADAS-Cog11 as the primary outcome, we defined practice effects based on the improvement in the first two ADAS-Cog11 scores and then estimated the presence of practice effects and compared the cognitive progression between participants with and without practice effects. The robustness of practice effects was investigated using CDR SB, an outcome independent the definition itself. Furthermore, we evaluated how practice effects can affect sample size estimation. RESULTS: The overall percent of practice effects for AD participants was 39.0% and 53.3% for MCI participants. For AD studies, the mean change from baseline to 2 years was 12.8 points for the non-practice effects group vs 7.4 for the practice effects group; whereas for MCI studies, it was 4.1 for non-practice effects group vs 0.2 for the practice effects group. AD participants without practice effects progressed 0.9 points faster than those with practice effects over a period of 2 years in CDR-SB; whereas for MCI participants, the difference is 0.7 points. The sample sizes can be different by over 35% when estimated based on participants with/without practice effects. CONCLUSION: Practice effects were prevalent and robust in persons with AD or MCI and affected the cognitive progression and sample size estimation. Planning of future AD or MCI clinical trials should account for practice effects to avoid underpower or considers target trials or stratification analysis based on practice effects

Improved antimicrobial activity of nisin-incorporated polymer films by formulation change and addition of food grade chelator

Aims: The following polymers were developed: polyethylene (PE), a PE and polyethylene oxide (70% PE and 30% PEO; PE + PEO) blend, PE and nisin (PE + nisin), PE, nisin, and EDTA (PE + nisin + EDTA), and PE + PEO with nisin (PE + PEO + nisin). Methods and Results: Of the polymers tested, PE and PE + PEO did not exhibit any antimicrobial activity against Brochothrix thermosphacta (BT); however, PE + nisin, PE + nisin + EDTA, and PE + PEO + nisin did. Beef surfaces were experimentally inoculated with 3·50 log10 cfu/cm2 of BT, vacuum packaged with each of the five polymers, and held at 4°C for 21 d. After 3 d at 4°C, BT was reduced \u3e 1·70 log10 by PE + nisin and \u3e 3·50 log10 with PE + nisin + EDTA or PE + PEO + nisin. By 21 d at 4°C, BT was reduced to 0·30 log10 cfu/cm2 when treated with PE + PEO + nisin. Conclusions: It appears that PE + PEO + nisin or PE + nisin + EDTA were more effective for reducing BT, as compared to polymers composed of PE + nisin. Significance and Impact of the Study: Nisin-incorporated polymers may control the growth of undesirable bacteria, thereby extending the shelf life and possibly enhancing the microbial safety of meats

Distributions and abundances of Pacific sardine (Sardinops sagax) and other pelagic fishes in the California Current Ecosystem during spring 2006, 2008, and 2010, estimated from acoustic–trawl surveys

The abundances and distributions of coastal pelagic fish species in the California Current Ecosystem from San Diego to southern Vancouver Island, were estimated from combined acoustic and trawl surveys conducted in the spring of 2006, 2008, and 2010. Pacific sardine (Sardinops sagax), jack mackerel (Trachurus symmetricus), and Pacific mackerel (Scomber japonicus) were the dominant coastal pelagic fish species, in that order. Northern anchovy (Engraulis mordax) and Pacific herring (Clupea pallasii) were sampled only sporadically and therefore estimates for these species were unreliable. The estimates of sardine biomass compared well with those of the annual assessments and confirmed a declining trajectory of the “northern stock” since 2006. During the sampling period, the biomass of jack mackerel was stable or increasing, and that of Pacific mackerel was low and variable. The uncertainties in these estimates are mostly the result of spatial patchiness which increased from sardine to mackerels to anchovy and herring. Future surveys of coastal pelagic fish species in the California Current Ecosystem should benefit from adaptive sampling based on modeled habitat; increased echosounder and trawl sampling, particularly for the most patchy and nearshore species; and directed-trawl sampling for improved species identification and estimations of their acoustic target stre

Improved antimicrobial activity of nisin-incorporated polymer films by formulation change and addition of food grade chelator

Aims: The following polymers were developed: polyethylene (PE), a PE and polyethylene oxide (70% PE and 30% PEO; PE + PEO) blend, PE and nisin (PE + nisin), PE, nisin, and EDTA (PE + nisin + EDTA), and PE + PEO with nisin (PE + PEO + nisin). Methods and Results: Of the polymers tested, PE and PE + PEO did not exhibit any antimicrobial activity against Brochothrix thermosphacta (BT); however, PE + nisin, PE + nisin + EDTA, and PE + PEO + nisin did. Beef surfaces were experimentally inoculated with 3·50 log10 cfu/cm2 of BT, vacuum packaged with each of the five polymers, and held at 4°C for 21 d. After 3 d at 4°C, BT was reduced \u3e 1·70 log10 by PE + nisin and \u3e 3·50 log10 with PE + nisin + EDTA or PE + PEO + nisin. By 21 d at 4°C, BT was reduced to 0·30 log10 cfu/cm2 when treated with PE + PEO + nisin. Conclusions: It appears that PE + PEO + nisin or PE + nisin + EDTA were more effective for reducing BT, as compared to polymers composed of PE + nisin. Significance and Impact of the Study: Nisin-incorporated polymers may control the growth of undesirable bacteria, thereby extending the shelf life and possibly enhancing the microbial safety of meats

The biomechanical strength of olecranon fixation constructs: a systematic review and meta-regression

Olecranon fractures are often operative when displaced over 2 mm, but the most stable fixation construct is debated. The purpose of this study was to provide an overview of biomechanical properties of the most commonly used surgical fixations of olecranon fractures. This systematic review included 13 biomechanical studies comparing displacement during cyclic loading of olecranon fractures fixated with either tension band wiring (TBW), intramedullary screw, or plate fixation. In regard to overall gapping, plates displayed (and screws trended towards) increased stability versus TBW. However, there was no difference between the constructs in gapping at the articular surface. Plating displayed increased stability along the posterior surface. No construct allowed gapping over 2 mm, suggesting safe early post-operative motion with any of the techniques

Reading sentences of uniform word length II: very rapid adaptation of the preferred saccade length

In the current study we investigated whether readers adjust their preferred saccade length (PSL) during reading on a trial-by-trial basis. The PSL refers to the distance between a saccade launch site and saccade target (i.e., the word center during reading) when participants neither undershoot nor overshoot this target (McConkie, Kerr, Reddix, & Zola, 1988). The tendency for saccades longer or shorter than the PSL to under or overshoot their target is referred to as the range error. Recent research by Cutter, Drieghe, and Liversedge (2017) has shown that the PSL changes to be shorter when readers are presented with thirty consecutive sentences exclusively made of three letter words, and longer when presented with thirty consecutive sentences exclusively made of five letter words. We replicated and extended this work by this time presenting participants with these uniform sentences in an unblocked design. We found that adaptation still occurred across different sentence types despite participants only having one trial to adapt. Our analyses suggested that this effect was driven by the length of the words readers were making saccades away from, rather than the length of the words in the rest of the sentence. We propose an account of the range error in which readers use parafoveal word length information to estimate the length of a saccade between the centre of two parafoveal words (termed the Centre-Based Saccade Length) prior to landing on the first of these words

Late results of surgical and medical therapy for patients with coronary artery disease and depressed left ventricular function

Late survival and freedom from myocardial infarction were determined for 192 patients with coronary artery disease and depressed left ventricular ejection fraction at rest (<35%) determined by biplane angiography who were evaluated between 1970 and 1977. Seventy-seven patients had coronary artery bypass grafting and 115 patients were treated medically and were considered surgical candidates. The medical and surgical groups were comparable in all baseline characteristics examined except frequency of three vessel disease and angina pectoris, which occurred in a significantly greater percent of the surgically treated patients (p < 0.01). Only three medically treated patients (2.6%) underwent coronary bypass grafting in the follow-up period.Seven year actuarial survival was 63% in the surgical and 34% in the medical group (p < 0.001). Ninety-three percent of patients in the surgical group and 81% of those in the medical group were free of nonfatal myocardial infarction (p = 0.01), and 62 and 33%, respectively, were alive and free of myocardial infarction (p < 0.001) at 7 years. Significant differences in survival favoring surgical treatment were observed for the subsets of patients with an ejection fraction of 25% or less (p = 0.0002) and 26 to 35% (p = 0.01), and for the subsets with three vessel coronary disease (p < 0.001), normal left ventricular end-diastolic volume (<100 ml/m2) (p = 0.005) and elevated end-diastolic volume (>100 ml/m2)(p = 0.001). After adjustment for other important prognostic variables, the type of treatment remained significant in predicting the relative risk (medical to surgical) of mortality at 5 and 7 years (2.58 and 2.12, respectively).These data corroborate the trends observed in several randomized trials of medical and surgical therapy in patients with abnormal left ventricular function. If hospital mortality for coronary artery bypass grafting is less than 5%, substantial benefit can be anticipated for the majority of patients with depressed ventricular function