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Towards a Theory of Teacher Agency: Conceptualizing the Political Positions and Possibilities of Teacher Movements
In response to a need for increased engagement given the #RedForEd movement, this article draws upon my experience as an organizer and participant in the recent wave of teacher activism to provide implications for theories of teacher agency and political transformation. First, I conceptualize the Arizona #RedForEd movement’s unique position beyond the state’s logics of political power, considering the possibilities that such a position created for teacher-activists in Arizona. I then confront the decreasing power of the movement in order to demonstrate the need for increased theorizations of the reflexive capacities of institutionalized power structures to sustain oppositional education social movements. I consider the recent history of the RedForEd movement with the hope of forwarding renewed considerations of political transformation, power, and teacher agency, which can inform movements that challenge the hegemonic limits placed upon social-justice-oriented movement work
The Asylum Claim for Victims of Attempted Trafficking
The state of the law regarding refugees in the United States has been characterized in the recent past by inconsistent rulings among the Circuit Courts, and narrow applications of the Immigration and Nationality Act of 1952, which provides the basis for asylum eligibility. In the midst of this sometimes-contradictory application of the INA, victims of attempted sex trafficking (those who have faced threats or attempts by sex traffickers to force them into sexual slavery) have consistently been rejected for asylum by U.S. courts. Federal courts have uniformly denied these asylum claims by ruling that these victims do not meet the INA’s requirement that refugees fall into a particular social group. Therefore, this Comment focuses largely on the argument that U.S. courts have interpreted the “social group” provision in an unduly narrow fashion, and that victims of attempted trafficking do indeed satisfy this element of the INA’s test for asylum eligibility. This Comment argues that U.S. courts’ rejections of these asylum claims are inconsistent with the legislative intent behind the Immigration and Nationality Act of 1952, federal case law that has granted asylum petitions in similar contexts, and the United Nations’ and international interpretations of refugee law. Based on these reasons and public policy concerns, U.S. courts should recognize the valid claims of many of these victims of attempted trafficking, and grant them the asylum that they deserve
Using Microwells for Controlled Intestinal Differentiation of hiPS Cells
Recent advancements in developmental biology and tissue engineering have greatly contributed to pharmaceuticals and drug testing by allowing for the development of more efficient and accurate in-vitro models of human tissues. In particular, the Wells lab, at the Cincinnati Childrens Hospital Medical Center, has developed a protocol for the differentiation of human induced pluripotent stem cells (hiPS cells) into intestinal organoids. However, this protocol, which mimics the in vivo microenvironment of developing definitive endoderm and mid-hindgut, often results in the random generation of gut spheroids, which later mature into organoids. The complex development of hindgut does not allow for finer analysis of the local environment pertinent to the development of an individual spheroid. To address this problem, we employed hydrogel-based microwells. By attempting to differentiate hiPS cells into mid-hindgut tissue in microwells of varying 2D dimensions, depth, and spacing, we were able to deduce more optimal conditions for the in vitro development of individual spheroids. This method will allow for improved analysis of the local factors important for spheroid generation because it reduces the previously complex culture over a relatively large surface area to the smallest-budding unit. Using this approach to gain a better understanding of the local environment may lead to an improved differentiation protocol that will result in more organized intestinal tissue useful for drug testing and disease modelling.National Science Foundation under the Science and Technology Center Emergent Behaviors of Integrated Cellular Systems (EBICS).Grant Number CBET-0939511Ope
Seismic stability of L-shaped retaining wall with pseudostatic and time-history based dynamic analyses: application to a case study
Μελέτη και Ανάπτυξη Αλγορίθμου Βέλτιστης Tοποθέτησης Μονάδων Φασιθετών με Χρήση Μοντέλου Μειωμένης Τάξης και Τεχνικών Ημιορισμένου Προγραμματισμού
191 σ.Τα τελευταία χρόνια τα δίκτυα ηλεκτρικής ενέργειας γίνονται όλο και περισσότερο πολύπλοκα εξαιτίας τις επέκτασής τους, καθώς επίσης και λόγο της απελευθέρωσης της αγοράς. Για το λόγο αυτό είναι επιτακτική η ανάγκη συνεχόμενης επιτήρησης και παρατηρησιμότητας των συστημάτων ηλεκτρικής ενέργειας. Πρωταγωνιστικό ρόλο στην εποπτεία, καθώς επίσης και στην εύρυθμη λειτουργία των ηλεκτρικών δικτύων κατέχουν τα κέντρα ελέγχου ενέργειας, τα οποία συλλέγουν τα δεδομένα από διάφορους υποσταθμούς του συστήματος και πραγματοποιούν ανάλυση της παρατηρησιμότητας και ανάλυση της εκτίμησης κατάστασης του δικτύου. Τα δεδομένα που λαμβάνουν τα κέντρα ελέγχου ώστε να προχωρήσουν στις παραπάνω μελέτες είναι κατά κύριο λόγο συμβατικές μετρήσεις SCADA, δηλαδή μετρήσεις ενεργών και άεργων ροών ισχύος, μετρήσεις ενεργών και άεργων εγχύσεων ισχύος σε ζυγούς και μετρήσεις του μέτρου της τάσης σε συγκεκριμένους ζυγούς του ηλεκτρικού δικτύου.
Στις μέρες μας, με την ταχεία ανάπτυξη των δορυφορικών συστημάτων και πιο συγκεκριμένα του GPS, έχουν αναπτυχθεί νέας τεχνολογίας μετρήσεις στα συστήματα ηλεκτρικής ενέργειας. Οι συγχρονισμένες μετρήσεις μονάδων φασιθετών, είναι σύγχρονες μετρήσεις μεγαλύτερης ακρίβειας από τις συμβατικές, έχουν βελτιωμένη συχνότητα μετάδοσης και είναι χρονικά σφραγισμένες μετρήσεις. Οι μονάδες μετρήσεις φασιθετών PMU, τοποθετούνται σε ζυγούς των συστημάτων ηλεκτρικής ενέργειας και πραγματοποιούν μετρήσεις πραγματικού χρόνου του φασιθέτη της τάσης στον ζυγό εγκατάστασης, καθώς επίσης και των φασιθετών ρεύματος που αναχωρούν από αυτό τον ζυγό.
Στην παρούσα διπλωματική εργασία γίνεται προσπάθεια ανάλυσης της παρατηρησιμότητας δικτύων ηλεκτρικής ενέργειας, μέσω τεχνικών δημιουργίας παρατηρήσιμων νησίδων. Για την υλοποίηση της παραπάνω διαδικασίας πρέπει στην είσοδο του αλγορίθμου να υπάρχει η τοπολογία του κυκλώματος καθώς και ένα σύνολο συμβατικών μετρήσεων SCADA. Εάν το δίκτυο ηλεκτρικής ενέργειας δεν είναι πλήρως παρατηρήσιμο, τότε πραγματοποιείται βέλτιστη τοποθέτηση μονάδων φασιθετών σε κομβικά σημεία του δικτύου, με σκοπό την αποκατάσταση της παρατηρησιμότητάς του. Η βέλτιστη τοποθέτηση των μονάδων PMU κάνει χρήση τεχνικών ημιορισμένου προγραμματισμού. Για την υλοποίηση των παραπάνω αλγορίθμων χρησιμοποιήθηκε το περιβάλλον προγραμματισμού του μαθηματικού προγράμματος MATLAB, ενώ τα ηλεκτρικά δίκτυα όπου πραγματοποιήθηκαν οι μελέτες είναι πρότυπα δίκτυα της ΙΕΕΕ.Through the last years power electrical systems become more and more complex due to their expansive use in conjunction with the market liberalization. This is the reason why the need of continuous surveillance and observability of power electrical systems is rather imperative. Energy control centers play a key role in supervision and proper functioning of electrical systems by collecting data from different substations as well as by analyzing the observability and evaluation of system status. The data used in the above process is primarily conventional measurements SCADA, which can be described as measurements of active and reactive power flows and measurements of the drift in buses.
Nowadays, the fast development of satellite systems and especially the Global Positioning System (GPS) has brought innovative measurements in power electrical systems. Synchronized phasor measurements are measurements of higher accuracy than the conventional ones, with improved transmission frequency and time-limited. Phasor measurements units (PMU) develop real –time measurements of the phasor in the installed bus.
The dissertation analyzes the observability of power electrical systems through the method of creating observable islands. This process is accomplished by inserting the network’s topology and conventional SCADA measurements when entering the algorithm. In case that a power electrical system is not fully observable, then is introduced an optimum placement of phasor units in key points of the system aiming at the restoration of observability. The above algorithms were produced using the MATLAB programming system, while the electrical systems used for the research are standard networks of IEEE.Γεώργιος Ι. Καρβέλη
Protiškai atsilikusių vaikų palyginimo operacijos dinamika konstruojant
Many soviet psychologists studied comparison processes in mentally retarded children, but this field remains little explored in terms of the working constructional activity of mentally retarded children. The analysis of the handicraft lessons for mentally retarded children and our experimental constructional tasks showed that in practical activities while performing constructional tasks children encounter the necessity to compare work materials according to their features as well as compare own work with an example in order to evaluate the quality of own product.
We performed an experiment with the students of 1st-3rd assisted grade. The children needed to compare own product with an example while performing the task.
The first and the second activity series included the same task: to assemble an object from given parts according to given example. Other experimental activities were also performed during which the children were taught how to perform a comparison. The essence of the experiment was that the student did not receive an imposed solution to a mental task. If the student encountered difficulties in performing the task, it was explained and the student received an advised solution.
After the teaching experiment the children began to reproduce the examples better in their products. The similarity between example and product increased significantly and the students could qualitatively compare own products with an example. Teaching of comparison in the process of constructional activity creates the grounds for further skills development of assisted school students.Protiškai atsilikusių vaikų palyginimo procesus tyrinėjo nemažai tarybinių psichologų-defektologų: L. Zankovas, Ž. Šif, P. Solovjovas, M. Zvereva, A. Lipkina, B. Pinskij, V. Postovskaja ir kt. Tačiau šis klausimas tebėra mažai ištirtas protiškai atsilikusių vaikų darbinės konstravimo veiklos sąlygomis. Protiškai atsilikusių vaikų darbų pamokų analizė bei mūsų atlikti eksperimentiniai konstravimo užsiėmimai parodė, kad daiktinės-praktinės veiklos metu atliekant konstravimo užduotis vaikai susiduria su būtinumu lyginti dirbinių medžiagas pagal jų savybes, o taip pat lyginti savo dirbinį su pavyzdžiu, kad galėtų įvertinti savojo gamybos kokybę. Mes atlikome eksperimentą su I-III pagalbinės mokyklos klasių mokiniais ir masinės mokyklos pirmokais, kurio metu vaikai, atlikdami užduotį, turėjo nuolat lyginti savo gaminamą daiktą su pavyzdžiu. Pirmoje ir antroje užsiėmimų serijose mokiniams buvo keliama ta pati užduotis: pagal pateiktą pavyzdį iš paruoštų detalių pagaminti sukutį, žaislinį rašomąjį staliuką, žaislinį vežimėlį ir kt., trečioje kontrolinėje užsiėmimų serijoje – iš paruoštų detalių jie turėjo pagaminti žaislinį traktorių. Be to, mokiniai turėjo sukonstruoti pagal pateikiamą pavyzdį keletą figūrų iš skirtingo dydžio mažų tašelių, o taip pat sudėti pateiktus paveikslėlius iš atitinkamų kubelių, kurie sudarė tų paveikslėlių dalis. Tyrimai rodo, kad vaiko protinių veiksmų pagerėjimas, būtent gebėjimas lyginti, gali atsirasti tik tikslingai nukreipiant auklėjamąjį darbą. Remiantis tuo buvo atlikti kiti eksperimentiniai užsiėmimai, kurių metu vaikai buvo mokomi atlikti palyginimus. Mokomojo eksperimento esmė buvo ta, kad mokiniui nebuvo primetamas gatavas protinės užduoties sprendimas. Jeigu mokinys patirdavo sunkumų sprendžiant užduotį, mes ją paaiškindavome ir patardavome sprendimo būdą. Po mokomojo eksperimento vaikai pradėjo tiksliau atgaminti pavyzdžius savo dirbiniuose. Nors dėka to panašumas tarp pavyzdžio ir pagaminto daikto žymiai išaugo, mokiniai kokybiškai geriau lygino savo dirbinius su pavyzdžiu. Pateiksime kai kuriuos duomenis kokybinių mokinių sugebėjimo lyginti poslinkių iliustracijai. 1. Visų pirma reikia pažymėti, kad po antrosios užsiėmimų serijos staigiai padidėjo savarankiškai pradėjusių lyginti savo dirbinį su pavyzdžiu mokinių skaičius ( nuo 5 iki 50 %). 2. Po antrosios serijos išaugo palyginimo išsamumas pagal detales ir jų sąryšį, tuo tarpu pirmojoje serijoje palyginimas iš esmės tebuvo tik teigimas apie objektų panašumą. 3. Pasikeitė palyginimo būdai: nuo gana globalaus nediferencijuoto lyginimo „iš akies“ mokiniai daugiausia perėjo prie lyginimo matuojant. Mokymas lyginti konstruktyvaus veiksmo procese sudaro pagrindą tolimesniam pagalbinės mokyklos mokinių gebėjimų lyginti vystymuisi
Perceptual Bayesian inference in autism and schizophrenia
Recent theories in the field of computational psychiatry regard schizophrenia
(SCZ) and autistic spectrum disorders (ASD) as impairments in Bayesian inference
performed by the brain. In Bayesian terms, perception is a result of optimal real-time integration of sensory information (’likelihood’), which is intrinsically noisy and ambiguous, and prior expectations about the states of the world (‘prior’), which serve to disambiguate the meaning of the sensory information. Priors capture statistical regularities in the environment and are constantly updated to keep up with any changes in these regularities. The extent to which prior or likelihood dominate perception depends on the uncertainty with which they are represented, with less uncertainty resulting in more influence. Individuals with ASD and SCZ might show impairments in how they update their priors and/or how much uncertainty there is ascribed to prior and likelihood representations, leading to differences in inference. While this Bayesian account can be argued to be consistent with many previous experimental findings and symptoms of SCZ and ASD, recent experimental work inspired by these ideas has produced mixed results.
In this work, we investigated possible Bayesian impairments in SCZ and ASD experimentally by addressing some of the methodological limitations of the previous work. Most notably, we used an experimental design that allows to disentangle and quantify separate influences of priors and likelihoods, and we tested both SCZ and ASD patient groups as well as autistic and schizotypy traits in the general population. We administered a visual motion perception task that
rapidly induces prior expectations about the stimulus motion direction, leading
to biases and occasional hallucinations that can be well described by a Bayesian
model. In this task, autistic traits were found to be associated with reduced
biases, which was underlied by more precise sensory representations, while the
acquired priors were not affected by autistic traits. Patients with ASD, however,
showed no evidence of increased sensory precision, while there also were no impairments in the acquisition of priors. We also found no effects in the acquisition of priors or sensory representations along schizotypy traits and in patients with SCZ. However, under conditions of high ambiguity SCZ patients were less likely to hallucinate the stimulus than controls.
The second part of the thesis is focused on further exploratory analyses conducted using these same datasets. First, we investigated post-perceptual repulsion effects in our task and whether they were related to trait or group differences. We found clear evidence of repulsion from the cardinal directions. In addition to that, we found evidence for a repulsion from the central reference angle, which was randomly selected for each participant and which could only be inferred from the stimulus statistics. Furthermore, we found the repulsion from the central reference angle to be reduced along schizotypy traits. Interestingly, in both SCZ and ASD groups this repulsion was also found to be negligible. While these results are exploratory, they might point to a trans-diagnostic features of ASD and SCZ. Second, we investigated within-trial dynamics of evidence accumulation by constructing a Continuous Choice Drift Diffusion Model (CDM) – an extension of the classical binary choice drift diffusion model. The results of this model showed that increased sensory precision along AQ found in a Bayesian model was underlied by faster drift rates, while slower responses and reduced hallucinations in SCZ were explained by a larger decision threshold. In addition, this model provided a more complete characterization of the performance in this task (by including reaction times) and it serves to emphasize the importance of accounting for exposure to stimulus duration and judgement time in future studies investigating Bayesian inference.
Together, this work provides novel experimental evidence that speaks to the
hypothesis of impaired Bayesian inference in ASD and SCZ. Furthermore, the
analysis of reference repulsion effects and within-trial dynamics provide additional insight related to SCZ and ASD differences that extend beyond the Bayesian framework
Visual statistical learning and integration of perceptual priors are intact in attention deficit hyperactivity disorder
BackgroundDeficits in visual statistical learning and predictive processing could in principle explain the key characteristics of inattention and distractibility in attention deficit hyperactivity disorder (ADHD). Specifically, from a Bayesian perspective, ADHD may be associated with flatter likelihoods (increased sensory processing noise), and/or difficulties in generating or using predictions. To our knowledge, such hypotheses have never been directly tested.MethodsWe here test these hypotheses by evaluating whether adults diagnosed with ADHD (n = 17) differed from a control group (n = 30) in implicitly learning and using low-level perceptual priors to guide sensory processing. We used a visual statistical learning task in which participants had to estimate the direction of a cloud of coherently moving dots. Unbeknown to the participants, two of the directions were more frequently presented than the others, creating an implicit bias (prior) towards those directions. This task had previously revealed differences in other neurodevelopmental disorders, such as autistic spectrum disorder and schizophrenia.ResultsWe found that both groups acquired the prior expectation for the most frequent directions and that these expectations substantially influenced task performance. Overall, there were no group differences in how much the priors influenced performance. However, subtle group differences were found in the influence of the prior over time.ConclusionOur findings suggest that the symptoms of inattention and hyperactivity in ADHD do not stem from broad difficulties in developing and/or using low-level perceptual priors
Instruments of Power. The affective power of sound design in American music education
Music education in the United States has increasingly focused upon student creativity and practices such as improvisation. While such practices and changes are often conceptualized as flexible, inclusive reforms about making kinds of children, historically the curriculum has little to do with music and is instead concerned with taming uncertainty in the governing of child. We examine the Orff-Schulwerk pedagogy in the teaching of music, thought of as a progressive reform which emphasized improvisation and creativity. Exploring briefly Orff-Schulwerk’s production in the Weimar Republic as it travels and translated into the post-war United States, we consider the curriculum as formed through psychological research about rationality, choice, and creativity. The focus is on the system of reasoning embodied in the curriculum as generating principles about desired kind of persons in a stable, secure future related to salvation narratives- principles different in the Weimar Republic and US. The shifting design of people in Orff-Schulwerk curriculum and classroom instruments for learning of sound are, we argue, practices in governing of the body and soul. The fabricating and mapping in the music curriculum is about kinds of populations required as evidence of the progressive desires that simultaneously distributes differences
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