2,138 research outputs found
Change in the embedding dimension as an indicator of an approaching transition
Predicting a transition point in behavioral data should take into account the complexity of the signal being influenced by contextual factors. In this paper, we propose to analyze changes in the embedding dimension as contextual information indicating a proceeding transitive point, called OPtimal Embedding tRANsition Detection (OPERAND). Three texts were processed and translated to time-series of emotional polarity. It was found that changes in the embedding dimension proceeded transition points in the data. These preliminary results encourage further research into changes in the embedding dimension as generic markers of an approaching transition point
Weak values of electron spin in a double quantum dot
We propose a protocol for a controlled experiment to measure a weak value of
the electron's spin in a solid state device. The weak value is obtained by a
two step procedure -- weak measurement followed by a strong one
(post-selection), where the outcome of the first measurement is kept provided a
second post-selected outcome occurs. The set-up consists of a double quantum
dot and a weakly coupled quantum point contact to be used as a detector.
Anomalously large values of the spin of a two electron system are predicted, as
well as negative values of the total spin. We also show how to incorporate the
adverse effect of decoherence into this procedure.Comment: 4+ pages, 3 figures, final published versio
Dynamic patterns of expertise: The case of orthopedic medical diagnosis
The aim of this study was to analyze dynamic patterns for scanning femoroacetabular impingement (FAI) radiographs in orthopedics, in order to better understand the nature of expertise in radiography. Seven orthopedics residents with at least two years of expertise and seven board-certified orthopedists participated in the study. The participants were asked to diagnose 15 anteroposterior (AP) pelvis radiographs of 15 surgical patients, diagnosed with FAI syndrome. Eye tracking data were recorded using the SMI desk-mounted tracker and were analyzed using advanced measures and methodologies, mainly recurrence quantification analysis. The expert orthopedists presented a less predictable pattern of scanning the radiographs although there was no difference between experts and non-experts in the deterministic nature of their scan path. In addition, the experts presented a higher percentage of correct areas of focus and more quickly made their first comparison between symmetric regions of the pelvis. We contribute to the understanding of experts' process of diagnosis by showing that experts are qualitatively different from residents in their scanning patterns. The dynamic pattern of scanning that characterizes the experts was found to have a more complex and less predictable signature, meaning that experts' scanning is simultaneously both structured (i.e. deterministic) and unpredictable
Safety and short term outcomes of a new truly minimally-invasive mesh-less and dissection-less anchoring system for pelvic organ prolapse apical repair
Objective To evaluate the safety and short term outcomes of a new, truly
minimally-invasive, mesh-less and dissection-less anchoring system for pelvic
floor apical repair. Methods A prospective study was conducted using the
NeuGuide™ device system for pelvic floor apical repair. The primary
effectiveness outcome was centro-apical pelvic floor prolapse by POP-Q after
six months. The primary safety outcome was intra-operative, immediate (first
48 h) post-operative complications and adverse effects after six months. A
standardized questionnaire (UDI-6) to assess quality of life at entry and
during follow-up visits was used. Patients’ six months-follow-up and
evaluation are reported. Results The mean age of the study population (n=10)
was 63.8±12.0 years. All patients had a previous prolapse surgery. Five had a
previous hysterectomy and two had stress urinary incontinence symptoms. During
surgery six patients had a concurrent colporrhaphy. There was no injury to the
bladder, rectum, pudendal nerves, or major pelvic vessels and no febrile
morbidity was recorded. At six months, no cases of centro-apical recurrence
were noted. Patients were satisfied with the procedure and had favorable
quality of life scores. Using the UDI-6 questionnaire an improvement, in all
domains was seen. Moreover, although the sample size was small, the
improvement in urge and overflow incontinence related domains were
demonstrated to be statistically significant. Conclusions This new NeuGuide™
device allows rapid and safe introduction of a suspending suture through the
sacrospinous ligament and makes sacrospinous ligament fixation easy to
perform, while avoiding dissection and mesh complications
Skill obsolescence, vintage effects and changing tasks
Human capital is no doubt one of the most important factors for future economic growth and well-being. However, human capital is also prone to becoming obsolete over time. Skills that have been acquired at one point in time may perfectly match the skill requirements at that time but may become obsolete as time goes by. Thus, in the following paper, we study the depreciation processes of the human capital of workers performing different types of tasks with different skill requirements over a period of more than twenty years. We argue that two types of tasks must be distinguished: knowledge-based tasks and experience-based tasks. Knowledge-based tasks demand skills depending on the actual stock of technological knowledge in a society whereas experience-based tasks demand skills depending on personal factors and individual experience values. We show, by applying Mincer regressions on four different cross sections, that the human capital of people performing knowledge-based tasks suffers more from depreciation than the human capital of individuals performing experience-based tasks
Pause Point Spectra in DNA Constant-Force Unzipping
Under constant applied force, the separation of double-stranded DNA into two
single strands is known to proceed through a series of pauses and jumps. Given
experimental traces of constant-force unzipping, we present a method whereby
the locations of pause points can be extracted in the form of a pause point
spectrum. A simple theoretical model of DNA constant-force unzipping is
demonstrated to produce good agreement with the experimental pause point
spectrum of lambda phage DNA. The locations of peaks in the experimental and
theoretical pause point spectra are found to be nearly coincident below 6000
bp. The model only requires the sequence, temperature and a set of empirical
base pair binding and stacking energy parameters, and the good agreement with
experiment suggests that pause points are primarily determined by the DNA
sequence. The model is also used to predict pause point spectra for the
BacterioPhage PhiX174 genome. The algorithm for extracting the pause point
spectrum might also be useful for studying related systems which exhibit
pausing behavior such as molecular motors.Comment: 15 pages, 12 figure
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