Spatial Contextual Thresholding Technique: A Case Study to Detect Nodule of Thyroid in Ultrasound Images

2021 ◽  
pp. 93-106
Author(s):  
Anshu Singla ◽  
Chetna Kaushal ◽  
Vatsala Anand
Keyword(s):  
Ultrasound Images

Assessing the Validity of Ultrasound Imaging of Wrist Muscle Moment Arms through an Agar Phantom Experiment and In Vivo Case Study

2020 ◽  
Vol 22 ◽  
Author(s):  
Jonathan Charles ◽  
Jennifer A. Nichols
Keyword(s):  
Imaging Modality ◽  
Ultrasound Images ◽  
Flexor Digitorum Superficialis ◽  
Distance Measurements ◽  
Phantom Experiment ◽  
Measurement Variability ◽  
Moment Arms ◽  
Flexor Digitorum

Joints in the human body utilize torque to create movement, where a force F acts at a distance, r, from a rotation point. In biomechanics, F is generated by muscles acting on the joint, and r is the distance between the joint’s center of rotation (COR) and the muscle line of action. This distance r is known as a geometric moment arm (GMA). Changes in GMAs may be correlated with loss of muscle and hand function in people due to aging, injury, or pathology. To comprehensively evaluate GMAs, efficient and inexpensive methods for measuring them in vivo are needed. Thus, this study explores whether ultrasound is a valid imaging modality for quantifying the GMA of muscles crossing the wrist. An agar-gel phantom was used to determine if distance measurements from 20 ultrasound images of the phantom were accurate compared to a set of four baseline distances. A subsequent in vivo case study explored whether ultrasound could measure GMAs within a human wrist. The capitate bone was defined as the wrist’s COR due to its central location in the joint, and the measured GMA was defined between this COR and the flexor digitorum superficialis (FDS) muscle. Both studies returned data that exhibited low measurement variability over consecutive days and provided reasonable proof that ultrasound can accurately measure wrist GMAs.             Keywords: biomechanics, medical imaging, capitate, flexor digitorum superficialis 

The Genesis and Internal Dynamics of El Salvador's People's Revolutionary Army, 1970–1976

2014 ◽  
Vol 38 (01) ◽  
pp. 102-129
Author(s):  
ALBERTO MARTÍN ÁLVAREZ ◽  
EUDALD CORTINA ORERO
Keyword(s):  
Latin America ◽  
El Salvador ◽  
Early Years ◽  
Left Wing ◽  
Internal Dynamics ◽  
Internal Coherence ◽  
The 1960S

AbstractUsing interviews with former militants and previously unpublished documents, this article traces the genesis and internal dynamics of the Ejército Revolucionario del Pueblo (People's Revolutionary Army, ERP) in El Salvador during the early years of its existence (1970–6). This period was marked by the inability of the ERP to maintain internal coherence or any consensus on revolutionary strategy, which led to a series of splits and internal fights over control of the organisation. The evidence marshalled in this case study sheds new light on the origins of the armed Salvadorean Left and thus contributes to a wider understanding of the processes of formation and internal dynamics of armed left-wing groups that emerged from the 1960s onwards in Latin America.

Culture and the plasticity of perception

2020 ◽  
Vol 43 ◽  
Author(s):  
Michael Lifshitz ◽  
T. M. Luhrmann
Keyword(s):  
Cultural Context ◽  
Sensory Experience ◽  
Cultural Learning ◽  
The World

Abstract Culture shapes our basic sensory experience of the world. This is particularly striking in the study of religion and psychosis, where we and others have shown that cultural context determines both the structure and content of hallucination-like events. The cultural shaping of hallucinations may provide a rich case-study for linking cultural learning with emerging prediction-based models of perception.

Dual systems for all: Higher-order, role-based relational reasoning as a uniquely derived feature of human cognition

2019 ◽  
Vol 42 ◽  
Author(s):  
Daniel J. Povinelli ◽  
Gabrielle C. Glorioso ◽  
Shannon L. Kuznar ◽  
Mateja Pavlic
Keyword(s):  
Temporal Reasoning ◽  
Higher Order ◽  
Important Case ◽  
Human Cognition ◽  
Relational Reasoning ◽  
Dual Systems ◽  
First Order ◽  
Reasoning System ◽  
Role Based

Abstract Hoerl and McCormack demonstrate that although animals possess a sophisticated temporal updating system, there is no evidence that they also possess a temporal reasoning system. This important case study is directly related to the broader claim that although animals are manifestly capable of first-order (perceptually-based) relational reasoning, they lack the capacity for higher-order, role-based relational reasoning. We argue this distinction applies to all domains of cognition.

Sociocultural memory development research drives new directions in gadgetry science

2019 ◽  
Vol 42 ◽  
Author(s):  
Penny Van Bergen ◽  
John Sutton
Keyword(s):  
Episodic Memory ◽  
Autobiographical Memory ◽  
Developmental Psychology ◽  
Cross Cultural ◽  
Memory Development ◽  
Development Research ◽  
Cultural Research ◽  
New Directions ◽  
Cross Cultural Research

Abstract Sociocultural developmental psychology can drive new directions in gadgetry science. We use autobiographical memory, a compound capacity incorporating episodic memory, as a case study. Autobiographical memory emerges late in development, supported by interactions with parents. Intervention research highlights the causal influence of these interactions, whereas cross-cultural research demonstrates culturally determined diversity. Different patterns of inheritance are discussed.

Construction of plastic contact deformation maps on ceramics: a case study on aluminum nitride

1996 ◽  
Vol 54 ◽  
pp. 636-637
Author(s):  
D. L. Callahan
Keyword(s):  
Plastic Deformation ◽  
Aluminum Nitride ◽  
Mechanical Response ◽  
Three Dimensional ◽  
Bright Field Image ◽  
Perfectly Plastic ◽  
Contrast Analysis ◽  
Deformation Patterns

Modern polishing, precision machining and microindentation techniques allow the processing and mechanical characterization of ceramics at nanometric scales and within entirely plastic deformation regimes. The mechanical response of most ceramics to such highly constrained contact is not predictable from macroscopic properties and the microstructural deformation patterns have proven difficult to characterize by the application of any individual technique. In this study, TEM techniques of contrast analysis and CBED are combined with stereographic analysis to construct a three-dimensional microstructure deformation map of the surface of a perfectly plastic microindentation on macroscopically brittle aluminum nitride.The bright field image in Figure 1 shows a lg Vickers microindentation contained within a single AlN grain far from any boundaries. High densities of dislocations are evident, particularly near facet edges but are not individually resolvable. The prominent bend contours also indicate the severity of plastic deformation. Figure 2 is a selected area diffraction pattern covering the entire indentation area.

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