This work examined if currently available electromyography (EMG) driven models, that are calibrated to satisfy joint moments about one single degree of freedom (DOF), could provide the same ...musculotendon unit (MTU) force solution, when driven by the same input data, but calibrated about a different DOF. We then developed a novel and comprehensive EMG-driven model of the human lower extremity that used EMG signals from 16 muscle groups to drive 34 MTUs and satisfy the resulting joint moments simultaneously produced about four DOFs during different motor tasks. This also led to the development of a calibration procedure that allowed identifying a set of subject-specific parameters that ensured physiological behavior for the 34 MTUs. Results showed that currently available single-DOF models did not provide the same unique MTU force solution for the same input data. On the other hand, the MTU force solution predicted by our proposed multi-DOF model satisfied joint moments about multiple DOFs without loss of accuracy compared to single-DOF models corresponding to each of the four DOFs. The predicted MTU force solution was (1) a function of experimentally measured EMGs, (2) the result of physiological MTU excitation, (3) reflected different MTU contraction strategies associated to different motor tasks, (4) coordinated a greater number of MTUs with respect to currently available single-DOF models, and (5) was not specific to an individual DOF dynamics. Therefore, our proposed methodology has the potential of producing a more dynamically consistent and generalizable MTU force solution than was possible using single-DOF EMG-driven models. This will help better address the important scientific questions previously approached using single-DOF EMG-driven modeling. Furthermore, it might have applications in the development of human-machine interfaces for assistive devices.
Under Stalin's leadership, the Soviet government carried out a massive number of deportations, incarcerations, and executions. Paradoxically, at the very moment that Soviet authorities were killing ...thousands of individuals, they were also engaged in an enormous pronatalist campaign to boost the population. Even as the number of repressions grew exponentially, Communist Party leaders enacted sweeping social welfare and public health measures to safeguard people's well-being. Extensive state surveillance of the population went hand in hand with literacy campaigns, political education, and efforts to instill in people an appreciation of high culture.
InCultivating the Masses, David L. Hoffmann examines the Party leadership's pursuit of these seemingly contradictory policies in order to grasp fully the character of the Stalinist regime, a regime intent on transforming the socioeconomic order and the very nature of its citizens. To analyze Soviet social policies, Hoffmann places them in an international comparative context. He explains Soviet technologies of social intervention as one particular constellation of modern state practices. These practices developed in conjunction with the ambitions of nineteenth-century European reformers to refashion society, and they subsequently prompted welfare programs, public health initiatives, and reproductive regulations in countries around the world.
The mobilizational demands of World War I impelled political leaders to expand even further their efforts at population management, via economic controls, surveillance, propaganda, and state violence. Born at this moment of total war, the Soviet system institutionalized these wartime methods as permanent features of governance. Party leaders, whose dictatorship included no checks on state power, in turn attached interventionist practices to their ideological goal of building socialism.
Abstract Current electromyography (EMG)-driven musculoskeletal models are used to estimate joint moments measured from an individual׳s extremities during dynamic movement with varying levels of ...accuracy. The main benefit is the underlying musculoskeletal dynamics is simulated as a function of realistic, subject-specific, neural-excitation patterns provided by the EMG data. The main disadvantage is surface EMG cannot provide information on deeply located muscles. Furthermore, EMG data may be affected by cross-talk, recording and post-processing artifacts that could adversely influence the EMG׳s information content. This limits the EMG-driven model׳s ability to calculate the multi-muscle dynamics and the resulting joint moments about multiple degrees of freedom. We present a hybrid neuromusculoskeletal model that combines calibration, subject-specificity, EMG-driven and static optimization methods together. In this, the joint moment tracking errors are minimized by balancing the information content extracted from the experimental EMG data and from that generated by a static optimization method. Using movement data from five healthy male subjects during walking and running we explored the hybrid model׳s best configuration to minimally adjust recorded EMGs and predict missing EMGs while attaining the best tracking of joint moments. Minimally adjusted and predicted excitations substantially improved the experimental joint moment tracking accuracy than current EMG-driven models. The ability of the hybrid model to predict missing muscle EMGs was also examined. The proposed hybrid model enables muscle-driven simulations of human movement while enforcing physiological constraints on muscle excitation patterns. This might have important implications for studying pathological movement for which EMG recordings are limited.
Heusler alloys have been theoretically predicted and experimentally demonstrated to be an ideal spin source due to their half-metallicity at room temperature. The half-metallicity also offers low ...Gilbert damping constants for fast magnetization reversal with low switching current density. These intrinsic properties can offer better operationability in spin-transfer-torque-based devices. In addition spin–orbit torque can be exerted using Heusler alloys for spin Hall and caloritronic effects. These properties can be precisely controlled by substituting the constituent elements in a Heusler alloy. We review the recent development on these spintronic devices and summarize their future perspectives.
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Beckett was deeply engaged with the visual arts and individual painters, including Jack B. Yeats, Bram van Velde, and Avigdor Arikha. In this monograph, David Lloyd explores what Beckett saw in their ...paintings.
“Browning,” the appearance and activation of brown-in-white (brite) adipose cells within inguinal white adipose tissue (iWAT), and induction of uncoupling protein 1 (UCP1) correlate with fibroblast ...growth factor-21 (FGF21)-induced weight loss and glucose homeostasis improvements. Therefore, antiobesity therapies targeting browning and brite adipocyte activation are currently being sought. To test the dependence of weight loss on browning, we examined whether this event was responsible for FGF21-Fc’s beneficial effects. Lean and diet-induced obese mice housed at 21°C or 30°C that received FGF21-Fc exhibited similar degrees of body weight reduction and glucose homeostasis improvement. Substantial browning of iWAT occurred only in FGF21-Fc-treated lean mice housed at 21°C. Further, FGF21-Fc-treated Ucp1−/− mice showed robust improvements in body weight, glucose homeostasis, and plasma lipids, associated with increased energy expenditure and FGF21-Fc-induced Ppargc1 expression in iWAT. We conclude that FGF21 requires neither UCP1 nor brite adipocytes to elicit weight loss and improve glucose homeostasis.
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•The browning of white adipose tissue by FGF21 is temperature and diet dependent•FGF21’s antidiabetic and antiobesogenic effects are independent of brite adipocytes•FGF21 is efficacious in Ucp1 null mice
Part of the beneficial pharmacological effects of FGF21 therapy is ascribed to “browning” of white adipose tissue. Véniant et al. show here that FGF21-induced browning is temperature dependent and that the effects on body weight reduction and glucose homeostasis can occur in UCP1 KO mice
The first full-length study to show the profound relation between aesthetic philosophy and modern racial thinking.Under Representationoffers a clear and readable account of difficult but highly ...significant philosophical concepts and shows their relationship to the basic ways in which we think about race.Challenges both the paucity of sustained thought about race in postcolonial studies and the lack of attention to aesthetics in critical race theory.
Under Representationshows how the founding texts of aesthetic philosophy ground the racial order of the modern world in our concepts of universality, freedom, and humanity. Late Enlightenment discourse on aesthetic experience proposes a decisive account of the conditions of possibility for universal human subjecthood. The aesthetic forges a powerful "racial regime of representation" whose genealogy runs from Enlightenment thinkers like Kant and Schiller to late Modernist critics like Adorno and Benjamin. For aesthetic philosophy, representation is not just about depiction of diverse humans or inclusion in political or cultural institutions. It is an activity that undergirds the various spheres of human practice and theory, from the most fundamental acts of perception and reflection to the relation of the subject to the political, the economic, and the social.
Representation regulates the distribution of racial identifications along a developmental trajectory: The racialized remain "under representation," on the threshold of humanity and not yet capable of freedom and civility as aesthetic thought defines those attributes. To ignore the aesthetic is thus to overlook its continuing force in the formation of the racial and political structures down to the present.
Both a genealogy and an account of our present,Under Representationultimately helps show how a political reading of aesthetics can help us build a racial politics adequate for the problems we face today, one that stakes claims more radical than multicultural demands for representation.
Draws upon and significantly expands a highly influential and much cited article Lloyd wrote titled "Race Under Representation."There has recently been a significant renewal of interest in aesthetics in both philosophy and in literary and cultural criticism, but this is the only book that addresses head-on the role that aesthetics has played in shaping modern conceptions of race and of representation.
From the Famine to political hunger strikes, from telling tales in the pub to Beckett's tortured utterances, the performance of Irish identity has always been deeply connected to the oral. Exploring ...how colonial modernity transformed the spaces that sustained Ireland's oral culture, this book explains why Irish culture has been both so creative and so resistant to modernization. David Lloyd brings together manifestations of oral culture in the nineteenth and twentieth centuries, showing how the survival of orality was central both to resistance against colonial rule and to Ireland's modern definition as a postcolonial culture. Specific to Ireland as these histories are, they resonate with postcolonial cultures globally. This study is an important and provocative new interpretation of Irish national culture and how it came into being.
Abstract A challenging aspect of subject specific musculoskeletal modeling is the estimation of muscle parameters, especially optimal fiber length and tendon slack length. In this study, the method ...for scaling musculotendon parameters published by Winby et al. (2008) , J. Biomech. 41, 1682–1688, has been reformulated, generalized and applied to two cases of practical interest: 1) the adjustment of muscle parameters in the entire lower limb following linear scaling of a generic model and 2) their estimation “from scratch” in a subject specific model of the hip joint created from medical images. In the first case, the procedure maintained the muscles׳ operating range between models with mean errors below 2.3% of the reference model normalized fiber length value. In the second case, a subject specific model of the hip joint was created using segmented bone geometries and muscle volumes publicly available for a cadaveric specimen from the Living Human Digital Library (LHDL). Estimated optimal fiber lengths were found to be consistent with those of a previously published dataset for all 27 considered muscle bundles except gracilis . However, computed tendon slack lengths differed from tendon lengths measured in the LHDL cadaver, suggesting that tendon slack length should be determined via optimization in subject-specific applications. Overall, the presented methodology could adjust the parameters of a scaled model and enabled the estimation of muscle parameters in newly created subject specific models. All data used in the analyses are of public domain and a tool implementing the algorithm is available at https://simtk.org/home/opt_muscle_par.
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