353 research outputs found
Low-Grade Appendiceal Mucinous Neoplasm Involving the Endometrium and Presenting with Mucinous Vaginal Discharge.
Primary appendiceal mucinous lesions are uncommon and represent a spectrum from nonneoplastic mucous retention cysts to invasive adenocarcinoma. Low-grade appendiceal mucinous neoplasms (LAMNs) represent an intermediate category on this spectrum and can be classified according to whether or not they are confined to the appendix. Although LAMNs are frequently confined to the appendix, they can also spread to the peritoneum and clinically progress as pseudomyxoma peritonei (i.e., mucinous ascites). Thus, the appropriate classification of appendiceal primary neoplasia is essential for prognosis and influences clinical management. In addition, the precise classification, management, and clinical outcome of patients with disseminated peritoneal disease remain controversial. Here, we report an unusual case of LAMN with pseudomyxoma peritonei that initially presented with mucinous and bloody vaginal discharge. Pathological evaluation revealed low-grade appendiceal mucinous neoplasm with secondary involvement of the peritoneum, ovaries, and endometrial surface. Therefore, LAMN should be considered in the differential diagnosis of mucinous vaginal discharge
An Interactive System for Experimenting with Development Planning
An interactive system which is directed to serve as an instrument for resolving development planning problems is presented. Manuals for programmers and players and a few numerical examples are attached
Efficiently Combining Human Demonstrations and Interventions for Safe Training of Autonomous Systems in Real-Time
This paper investigates how to utilize different forms of human interaction
to safely train autonomous systems in real-time by learning from both human
demonstrations and interventions. We implement two components of the
Cycle-of-Learning for Autonomous Systems, which is our framework for combining
multiple modalities of human interaction. The current effort employs human
demonstrations to teach a desired behavior via imitation learning, then
leverages intervention data to correct for undesired behaviors produced by the
imitation learner to teach novel tasks to an autonomous agent safely, after
only minutes of training. We demonstrate this method in an autonomous perching
task using a quadrotor with continuous roll, pitch, yaw, and throttle commands
and imagery captured from a downward-facing camera in a high-fidelity simulated
environment. Our method improves task completion performance for the same
amount of human interaction when compared to learning from demonstrations
alone, while also requiring on average 32% less data to achieve that
performance. This provides evidence that combining multiple modes of human
interaction can increase both the training speed and overall performance of
policies for autonomous systems.Comment: 9 pages, 6 figure
VisokouÄinski modeli i simulacije ā konstrukcijska osnova mehatroniÄkih sustava
The paper describes the efficient techniques for assembly of multidisciplinary simulation models and then the efficient techniques for their simulation. The current methods of assembly of multidisciplinary simulation models are co-simulation using existing simulation packages for one physical domain and uniform modelling by uniform language. The efficiency of simulation can be achieved besides advanced mathematical methods by parallelization, modification of the problem being solved and surprisingly by solving boundary mapping instead of mapping of variable time behavior.U ovom radu opisane su uÄinkovite tehnike objedinjavanja multidisciplinarnih simulacijskih modela I njihove simulacije. Trenutno koriÅ”tene metode objedinjavanja simulacijskih modela su kosimulacija (kooperativna simulacija) na osnovi postojeÄih simulacijskih paketa za respektivna fizikalna podruÄja, te uniformno modeliranje standardnim jezikom. Osim koriÅ”tenja naprednih matematiÄkih metoda, uÄinkovitost simulacije postiže se paralelnim pristupom, modifikacijom promatranog problema i ā iznenaÄujuÄe ā rjeÅ”avanjem prikaza graniÄnog podruÄja umjesto prikaza ponaÅ”anja u varijablinom vremenu
Reading point-light walkers and amorphous: a TMS study
Objectives: (i) Evaluate if human actions with and without pictorial information result in comparable motor facilitation clarifying the adequacy of point-light (PL) human actions in motor observation and motor resonance research; (ii) Verify if the isolated aspects of human shape, i.e., without movement; and the isolated aspect of movement, i.e., PL in amorphous shape, are not enough for eliciting motor network response and thus that motor facilitation is specific to human action perception involving human motor and spatial configurations.
Research question: Are PL human actions suitable stimuli for action observation experiments evaluating motor resonance response and what are the adequate parameters for preparing their control stimuli?
Methods: Motor evoked potentials (MEPs) of M1 were recorded from 18 healthy subjects using transcranial magnetic stimulation (TMS) during presentation of full-body video clips of: everyday human actions either with (real movement - RM) or without (biological point-light - PLbio) pictorial information, scrambled moving point-lights (PLscr) and static point-lights forming a human shape (PLs). All videos were approximately 1000ms long. Peak-to-peak MEP amplitude (maximal distance) was individually averaged for each condition (RM, PLbio, PLscr, PLs). Results: rmANOVA considering MEP as dependent variable and condition as within-subject factor revealed a main effect for Stimuli (F1,17= 6.91; p=.029; np2 =.16). Specifically, Fisher LSD post hoc revealed that such effect was due to inferior MEP amplitude in PLs condition when compared to RM (p=.016), PLbio (p= .006) and PLscr (p=.047).
Conclusion: Our findings account for future studies elaboration by providing information on similar CE increase during PLbio and RM observation, thus corroborating the use of human PL in motor resonate/action observation studies. Noteworthy, PLscr also engaged the motor network, which could be due to kinematic aspects of human velocity profile or anthropomorphism of non- biological agents. Observation of PLs resulted in significantly smaller MEPs. Therefore, M1 activation seems restrict to movement perception but not to human form. Thus, planning the control stimuli and task context is crucial when using PL displays in the study of human action perception and the action observation network activation
Theoretical current-voltage characteristics of ferroelectric tunnel junctions
We present the concept of ferroelectric tunnel junctions (FTJs). These
junctions consist of two metal electrodes separated by a nanometer-thick
ferroelectric barrier. The current-voltage characteristics of FTJs are analyzed
under the assumption that the direct electron tunneling represents the dominant
conduction mechanism. First, the influence of converse piezoelectric effect
inherent in ferroelectric materials on the tunnel current is described. The
calculations show that the lattice strains of piezoelectric origin modify the
current-voltage relationship owing to strain-induced changes of the barrier
thickness, electron effective mass, and position of the conduction-band edge.
Remarkably, the conductance minimum becomes shifted from zero voltage due to
the piezoelectric effect, and a strain-related resistive switching takes place
after the polarization reversal in a ferroelectric barrier. Second, we analyze
the influence of the internal electric field arising due to imperfect screening
of polarization charges by electrons in metal electrodes. It is shown that, for
asymmetric FTJs, this depolarizing-field effect also leads to a considerable
change of the barrier resistance after the polarization reversal. However, the
symmetry of the resulting current-voltage loop is different from that
characteristic of the strain-related resistive switching. The crossover from
one to another type of the hysteretic curve, which accompanies the increase of
FTJ asymmetry, is described taking into account both the strain and
depolarizing-field effects. It is noted that asymmetric FTJs with dissimilar
top and bottom electrodes are preferable for the non-volatile memory
applications because of a larger resistance on/off ratio.Comment: 14 pages, 8 figure
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