2,191 research outputs found
Measurement of In Situ Acoustic Properties for the ONR Geoclutter Program, Annual Report, Geoclutter Program
Seafloor Characterization Through the Application of AVO Analysis to Multibeam Sonar Data
In the seismic reflection method, it is well known that seismic amplitude varies with the offset between the seismic source and detector and that this variation is a key to the direct determination of lithology and pore fluid content of subsurface strata. Based on this fundamental property, amplitude-versus-offset (AVO) analysis has been used successfully in the oil industry for the exploration and characterization of subsurface reservoirs. Multibeam sonars acquire acoustic backscatter over a wide range of incidence angles and the variation of the backscatter with the angle of incidence is an intrinsic property of the seafloor. Building on this analogy, we have adapted an AVO-like approach for the analysis of acoustic backscatter from multibeam sonar data. The analysis starts with the beam-by-beam time-series of acoustic backscatter provided by the multibeam sonar and then corrects the backscatter for seafloor slope (i.e. true incidence angle), time varying and angle varying gains, and area of insonification. Once the geometric and radiometric corrections are made, a series of “AVO attributes” (e.g. near, far, slope, gradient, fluid factor, product, etc.) are calculated from the stacking of consecutive time series over a spatial scale that approximates half of the swath width (both along track and across track). Based on these calculated AVO attributes and the inversion of a modified Williams, K. L. (2001) acoustic backscatter model, we estimate the acoustic impedance, the roughness, and consequently the grain size of the insonified area on the seafloor. The inversion process is facilitated through the use of a simple, interactive graphical interface. In the process of this inversion, the relative behavior of the model parameters is constrained by established inter-property relationships. The approach has been tested using a 300 kHz Simrad EM3000 multibeam sonar in Little Bay, N.H., an area that we can easily access for ground-truth studies. AVO-derived impedance estimates are compared to in situ measurements of sound speed and AVO-derived grain-size estimates are compared to the direct measurement of grain size on grab samples. Both show a very good correlation indicating the potential of this approach for robust seafloor characterization
Expression of the CD6 T lymphocyte differentiation antigen in normal human brain
Antigens shared by the immune and central nervous systems (CNS) have been described repeatedly.
The present study reports the expression of the CD6 lymphocyte differentiation antigen in normal human
brain evidenced by immunohistochemistry and Northern blot analysis. A panel of various anti-CD6
monoclonal antibodies (mabs) tested on serial cryostat sections identified CD6-positive cells randomly
scattered in parenchyma of all examined brain areas. Northern blot analysis with a highly sensitive cRNA
probe revealed a 3.1 kb CD6-specific mRNA in various brain regions, especially in basalganglia and cortex
cerebellum. Staining with mabs raised against different hematopoietic cell types, as well as hybridization
with probes specific for the ß- and y-T cell receptor (TCR) chains support the notion that CD6 is
expressed by original brain cells. The nature of the CD6-positive cell type and possible functions of shared
antigens in immune and nervous systems are discusse
Seafloor Characterization from Spatial Variation of Multibeam Backscatter vs. Best Estimated Grazing Angle
Backscatter vs. grazing angle, which can be extracted from multibeam backscatter data, depends on characteristics of the multibeam system and the angular responses of backscatter that are characteristic of different seafloor properties, such as sediment hardness and roughness. Changes in backscatter vs. grazing angle that are contributed by the multibeam system normally remain fixed over both space and time. Therefore, they can readily be determined and removed from backscatter data. The component of backscatter vs. grazing angle due to the properties of sediments varies from location to location, as the sediment changes. The sediment component of variability can be inferred using the redundant observations from different grazing angles in several small sections of seafloor assuming that the sediment property is uniform in any given section of seafloor yet varies from one section of the seafloor to another. The multibeam data used in this research is from the ONR sponsored STRATAFORM project. The location of the study area was the mid-outer continental shelf off New Jersey. A small subset (11 x 17 km) of the NJ multibeam survey was selected and divided into 1380 equal working cells. The backscatter vs. grazing angle dependence for each cell was computed by averaging backscatter data by the corresponding grazing angles using all data with the same grazing angle from different survey lines. Taking into account the effects of local topographic variations of the seabed, the estimated grazing angle for each beam has been computed from available adjacent soundings within a 15-meter radius using a least squares fit with a Butterfly weighting function. A graphic interface was developed to ease evaluation of the spatial variation of backscatter vs. grazing angle. With a mouse click, images based on different subsets of the data can be compared throughout the survey area. The subsets were created from specific grazing angles. These images show significant variations between nadir and off-nadir beams. Variations apparent in the images may provide some indication of the sediment (or seafloor) characteristics, which can be compared to ground truth data (sediment grain size) and measured values such as velocity and density
Description of Medical-Surgical Nurses Care of Patients at Risk for Pressure Ulcers
Aim: The purpose of this qualitative study was to explore and describe the level of understanding of PU development and prevention and perceptions of implementing PU prevention measures in nurses caring for patients in medical-surgical units. Method: The study was conducted in three (3) community hospitals within the same healthcare system using an Interpretive Description approach. Six (6) focus groups were conducted including thirty (30) participants. Findings: Participants described their knowledge of PU development and prevention as good and perceived continuing education as important in maintaining knowledge levels. Two (2) methods of identifying patients at risk for PU development were described: the Braden Scale and common patient diagnoses and conditions known to be associated with patients at risk for PU. Factors perceived to facilitate nurses\u27 implementation of PU prevention measures included personal motivation, use of evidence-based treatment protocols, availability of expert consultants, and leadership support. Barriers to nurses\u27 implementation of PU prevention measures perceived by study participants included the need to prioritize competing patient needs; lack of equipment and supplies; inadequate numbers and competency of staff; patient\u27s lack of or inability to cooperate; and family involvement. Finally, regulatory mandates limiting payment for hospital acquired PU were perceived by participants as a necessary measure and positive motivator in their implementation of PU prevention measures. Implications: Additional studies are needed to further describe differences between medical versus surgical patients and settings, the influence of patient families on nurses\u27 ability to provide care, and the influence of nurse leader and organizational culture on nurse motivation and performance. Organizations should implement evidence-based practice protocols, continue to provide ongoing education regarding PU prevention measures, and seriously consider adoption of the Wound Care Nurse role
Moving Beyond Lip Service: The Clinical Reasoning Behind Practicing Strengths
Social work has a long tradition of advocating for practice from the strengths perspective. However, it is unclear whether schools are truly preparing students for strengths based practice or whether they are simply teaching them to use the vocabulary of strengths without the clinical reasoning skills to switch paradigms from deficits to strengths, moving beyond lip service to real strengths-based practice. To explore this issue, data from an exercise in an MSW course was explored using qualitative methodology. The findings support that in addition to using a strengths vocabulary, other components are necessary for true implementation of a strengths approach. First, the data revealed a strengths-oriented structural model of an ideal process of clinical reasoning for approaching a client situation. Second, the process includes recognizing client strengths, reflecting on them with the client, and encouraging repetition and reinforcement of the client’s positive attitudes and actions. Finally, true strengths based understanding requires moving from social worker in the role of expert to social worker engaged in collaborative empowerment practice. These findings have implications for social work practice and education
Amino acid sequence of proteinase K from the mold Tritirachium album Limber Proteinase K — a subtilisin-related enzyme with disulfide bonds
AbstractThe amino acid sequence of proteinase K (EC 3.4.21.14) from Tritirachium album Limber has been determined by analysis of fragments generated by cleavage with CNBr or BNPS-skatole. The enzyme consists of a single peptide chain containing 277 amino acid residues, corresponding to Mr 28 930. Comparison of the sequence with those of the serine proteinases reveals a high degree of homology (about 35%) to the subtilisin-related enzyme. But in contrast to the subtilisins, proteinase K contains 2 disulfide bonds and a free cysteine residue. This finding may indicate that proteinase K is a member of a new subfamily of the subtilisins
Surface modification of aluminum by runaway electron preionized diffuse discharges in different gases at atmospheric pressure
The paper presents the results of an examination of aluminum samples exposed to runaway electron preionized diffuse discharges in air, nitrogen, and argon at atmospheric pressure. The changes in the chemical composition, structure, and hardness of the aluminum surface layers caused by the action of the discharge were investigated. It has been found that the oxygen and carbon concentrations in the surface layers depend on the number of discharge pulses and on the chemical composition of the working gas. The goal of the study was to find possible uses of runaway electron preionized diffuse discharges in research and industry
Die Kommunikative Theologie Matthias Scharers und ihre theoretische Bilanzierung mit Blick auf die Relevanz für das Schulfach Katholische Religion
In dieser Forschungsarbeit liegt die Grundposition in Form eines metaphorischen
Melkschemels dar, der sich auf die Freiheit der Allgemeinen Erklärung der
Menschenrechte von 1948, die Selbstverantwortung und Beteiligung der Gläubigen des
Theologenmemorandums von 2011 und der innerschulischen Erfolge des, von Studien
untersuchten, personenzentrierten Arbeitens des Carl R. Rogers konzentriert.
Von hier aus erarbeitet Kapitel Zwei das Spezifische der Kommunikativen Theologie
Matthias Scharers, um in Kapitel Drei den Fokus auf die Implikationen innerhalb der
Theologie sowie die theoretische Bilanzierung für den katholischen Religionsunterricht
eingehen zu können.
Versöhnend für die hier vorliegende Untersuchung weist sich der gemeinsame
Nährboden der Humanistischen Psychologie und Pädagogik aus.In dieser Forschungsarbeit liegt die Grundposition in Form eines metaphorischen
Melkschemels dar, der sich auf die Freiheit der Allgemeinen Erklärung der
Menschenrechte von 1948, die Selbstverantwortung und Beteiligung der Gläubigen des
Theologenmemorandums von 2011 und der innerschulischen Erfolge des, von Studien
untersuchten, personenzentrierten Arbeitens des Carl R. Rogers konzentriert.
Von hier aus erarbeitet Kapitel Zwei das Spezifische der Kommunikativen Theologie
Matthias Scharers, um in Kapitel Drei den Fokus auf die Implikationen innerhalb der
Theologie sowie die theoretische Bilanzierung für den katholischen Religionsunterricht
eingehen zu können.
Versöhnend für die hier vorliegende Untersuchung weist sich der gemeinsame
Nährboden der Humanistischen Psychologie und Pädagogik aus.The research surfaced in this study suggests that in order to engage pupils and
believers alike in an active fashion, assisting them in becoming democratic citizens as
well as participants in their belief systems in a multi-religious, multicultural Europe,
three legs of the metaphoric milking stool (chapter one) need to be held in steady
consciousness of (future) teaching staff: the freedom, proclaimed in the human right
declaration in 1948, the call for (amongst others) personal responsibility and active
involvement of believers published in the so called “Theologenmemorandum” with the
portentous title “Church 2011: The Need for a New Beginning Memorandum of
professors of theology on the crisis of the Catholic Church“, as well as the various
positive outcomes the person-centred approach by Carl R. Rogers is able to provide.
With this outlook, chapter two goes on to divulge the specifics of the Communicative
Theology of Matthias Scharer, leading up to its theoretical baseline, which is rooted in
the theme-centred interaction as developed by Ruth C. Cohn, and is explored further in
chapter three.
This theory based research lays the foundation for further research on how palpable an
impact the Communicative Theology might have on the religious education dynamics
and what its consequences for teachers and pupils might be.
Religious education is found to be a birthplace of theology in its own right, corroborating
God’s revelation to mankind, with its addressees as equally important to the
communicational procedures.
The conclusion centres around the fact that - with a common ground in Humanistic
Psychology and Pedagogy - the root bridge is to keep an autobiographical essence to
one’s work in teaching and in doing so, future teaching staff of theological courses or in
this case, religious education teachers at schools not only provide their pupils with
genuine experiences in and of themselves but manage to hand over self-reliance tools
which will in turn create active citizens and empowered believers
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