2,343 research outputs found
Influence of oxidative stress, diaphragm fatigue, and inspiratory muscle training on the plasma cytokine response to maximum sustainable voluntary ventilation
The influence of oxidative stress, diaphragm fatigue, and inspiratory muscle training (IMT) on the cytokine response to maximum sustainable voluntary ventilation (MSVV) is unknown. Twelve healthy males were divided equally into an IMT or placebo (PLA) group, and before and after a 6-wk intervention they undertook, on separate days, 1h of (1) passive rest and (2) MSVV, whereby participants undertook volitional hyperpnea at rest that mimicked the breathing and respiratory muscle recruitment patterns commensurate with heavy cycling exercise. Plasma cytokines remained unchanged during passive rest. There was a main effect of time (P < 0.01) for plasma interleukin-1 (IL-1) and interleukin-6 (IL-6) concentrations and a strong trend (P = 0.067) for plasma interleukin-1 receptor antagonist concentration during MSVV. Plasma IL-6 concentration was reduced after IMT by 27 + 18% (main effect of intervention, P = 0.029), whereas there was no change after PLA (P = 0.753). There was no increase in a systemic marker of oxidative stress [DNA damage in peripheral blood mononuclear cells (PBMC)], and diaphragm fatigue was not related to the increases in plasma IL-1 and IL-6 concentrations. A dose-response relationship was observed between respiratory muscle work and minute ventilation and increases in plasma IL-6 concentration. In conclusion, increases in plasma IL-1 and IL-6 concentrations during MSVV were not due to diaphragm fatigue or DNA damage in PBMC. Increases in plasma IL-6 concentration during MSVV are attenuated following IMT, and the plasma IL-6 response is dependent upon the level of respiratory muscle work and minute ventilation
Non-Volatile Memory Array Based Quantization- and Noise-Resilient LSTM Neural Networks
In cloud and edge computing models, it is important that compute devices at
the edge be as power efficient as possible. Long short-term memory (LSTM)
neural networks have been widely used for natural language processing, time
series prediction and many other sequential data tasks. Thus, for these
applications there is increasing need for low-power accelerators for LSTM model
inference at the edge. In order to reduce power dissipation due to data
transfers within inference devices, there has been significant interest in
accelerating vector-matrix multiplication (VMM) operations using non-volatile
memory (NVM) weight arrays. In NVM array-based hardware, reduced bit-widths
also significantly increases the power efficiency. In this paper, we focus on
the application of quantization-aware training algorithm to LSTM models, and
the benefits these models bring in terms of resilience against both
quantization error and analog device noise. We have shown that only 4-bit NVM
weights and 4-bit ADC/DACs are needed to produce equivalent LSTM network
performance as floating-point baseline. Reasonable levels of ADC quantization
noise and weight noise can be naturally tolerated within our NVMbased quantized
LSTM network. Benchmark analysis of our proposed LSTM accelerator for inference
has shown at least 2.4x better computing efficiency and 40x higher area
efficiency than traditional digital approaches (GPU, FPGA, and ASIC). Some
other novel approaches based on NVM promise to deliver higher computing
efficiency (up to 4.7x) but require larger arrays with potential higher error
rates.Comment: Published in: 2019 IEEE International Conference on Rebooting
Computing (ICRC
Mean field theory for collective motion of quantum meson fields
Mean field theory for the time evolution of quantum meson fields is studied
in terms of the functional Schroedinger picture with a time-dependent Gaussian
variational wave functional. We first show that the equations of motion for the
variational wavefunctional can be rewritten in a compact form similar to the
Hartree-Bogoliubov equations in quantum many-body theory and this result is
used to recover the covariance of the theory. We then apply this method to the
O(N) model and present analytic solutions of the mean field evolution equations
for an N-component scalar field. These solutions correspond to quantum
rotations in isospin space and represent generalizations of the classical
solutions obtained earlier by Anselm and Ryskin. As compared to classical
solutions new effects arise because of the coupling between the average value
of the field and its quantum fluctuations. We show how to generalize these
solutions to the case of mean field dynamics at finite temperature. The
relevance of these solutions for the observation of a coherent collective state
or a disoriented chiral condensate in ultra-relativistic nuclear collisions is
discussed.Comment: 31 pages, 2 Postscript figures, uses ptptex.st
Electron-hole bilayer quantum dots: Phase diagram and exciton localization
We studied a vertical ``quantum dot molecule'', where one of the dots is
occupied with electrons and the other with holes. We find that different phases
occur in the ground state, depending on the carrier density and the interdot
distance. When the system is dominated by shell structure, orbital degeneracies
can be removed either by Hund's rule, or by Jahn-Teller deformation. Both
mechanisms can lead to a maximum of the addition energy at mid-shell. At low
densities and large interdot distances, bound electron-hole pairs are formed.Comment: 10 pages, 3 figure
Quantum fields in disequilibrium: neutral scalar bosons with long-range, inhomogeneous perturbations
Using Schwinger's quantum action principle, dispersion relations are obtained
for neutral scalar mesons interacting with bi-local sources. These relations
are used as the basis of a method for representing the effect of interactions
in the Gaussian approximation to field theory, and it is argued that a marked
inhomogeneity, in space-time dependence of the sources, forces a discrete
spectrum on the field. The development of such a system is characterized by
features commonly associated with chaos and self-organization (localization by
domain or cell formation). The Green functions play the role of an iterative
map in phase space. Stable systems reside at the fixed points of the map. The
present work can be applied to self-interacting theories by choosing suitable
properties for the sources. Rapid transport leads to a second order phase
transition and anomalous dispersion. Finally, it is shown that there is a
compact representation of the non-equilibrium dynamics in terms of generalized
chemical potentials, or equivalently as a pseudo-gauge theory, with an
imaginary charge. This analogy shows, more clearly, how dissipation and entropy
production are related to the source picture and transform a flip-flop like
behaviour between two reservoirs into the Landau problem in a constant
`magnetic field'. A summary of conventions and formalism is provided as a basis
for future work.Comment: 23 pages revte
Strategies for enhancing CAR T cell expansion and persistence in HIV infection
Chimeric Antigen Receptor (CAR) T cell therapies are tremendously successful in hematological malignancies and show great promise as treatment and curative strategy for HIV. A major determinant for effective CAR T cell therapy is the persistence of CAR T cells. Particularly, antigen density and target cell abundance are crucial for the engagement, engraftment, and persistence of CAR T cells. The success of HIV-specific CAR T cells is challenged by limited antigen due to low cell surface expression of viral proteins and the scarcity of chronically infected cells during antiretroviral therapy. Several strategies have been explored to increase the efficacy of CAR T cells by enhancing expansion and persistence of the engineered cells. This review highlights the challenges of designing CAR T cells against HIV and other chronic viral infections. We also discuss potential strategies to enhance CAR T cell expansion and persistence in the setting of low antigen exposure
Sequential roles for myosin-X in BMP6-dependent filopodial extension, migration, and activation of BMP receptors
Endothelial cell migration is an important step during angiogenesis, and its dysregulation contributes to aberrant neovascularization. The bone morphogenetic proteins (BMPs) are potent stimulators of cell migration and angiogenesis. Using microarray analyses, we find that myosin-X (Myo10) is a BMP target gene. In endothelial cells, BMP6-induced Myo10 localizes in filopodia, and BMP-dependent filopodial assembly decreases when Myo10 expression is reduced. Likewise, cellular alignment and directional migration induced by BMP6 are Myo10 dependent. Surprisingly, we find that Myo10 and BMP6 receptor ALK6 colocalize in a BMP6-dependent fashion. ALK6 translocates into filopodia after BMP6 stimulation, and both ALK6 and Myo10 possess intrafilopodial motility. Additionally, Myo10 is required for BMP6-dependent Smad activation, indicating that in addition to its function in filopodial assembly, Myo10 also participates in a requisite amplification loop for BMP signaling. Our data indicate that Myo10 is required to guide endothelial migration toward BMP6 gradients via the regulation of filopodial function and amplification of BMP signals
Reuse of textile wastewater treated by moving bed biofilm reactor coupled with membrane bioreactor
This is the peer reviewed version of the following article: [ Yang, X, López-Grimau, V, Vilaseca, M, et al. Reuse of textile wastewater treated by moving bed biofilm reactor coupled with membrane bioreactor. Coloration Technol. 2021; 137: 484– 492. https://doi.org/10.1111/cote.12543], which has been published in final form at https://doi.org/10.1111/cote.12543. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.A laboratory-scale pilot plant of moving bed biofilm reactor coupled with membrane bioreactor (MBBR-MBR) was studied with regard to wastewater treatment in the textile industry, and the reuse feasibility of treated water was investigated. The pilot plant comprised two connected parts: an aerobic tank filled with carriers and a submerged membrane tank. The MBBR-MBR system reduced the hydraulic retention time to 1 day, which is very promising compared with conventional biological treatment in the textile industry. The removal efficiency of chemical oxygen demand reached 93%, which is almost the maximum for a biological process treating this type of wastewater, as well as the colour removal performance, which achieved 85%. Additionally, 99% of total suspended solids were removed due to filtration. Furthermore, new dyeing processes reusing the treated water were performed. The quality of the new dyed fabrics with treated water was compared with reference fabrics. Colour differences between new dyed fabrics and reference fabrics were found to be within the general requirement of the textile industry (¿ECMC(2:1) < 1). The reuse of treated water in new dyeing processes is beneficial both for the industry and for the environment, because the textile sector is an intensive water consumer during both the dyeing and finishing processes.This study is co-funded by ACCIÓ (Generalitat de Catalunya) within the REGIREU Project (COMRDI16-1-0062).Peer ReviewedPostprint (author's final draft
Influence of heavy modes on perturbations in multiple field inflation
We investigate linear cosmological perturbations in multiple field
inflationary models where some of the directions are light while others are
heavy (with respect to the Hubble parameter). By integrating out the massive
degrees of freedom, we determine the multi-dimensional effective theory for the
light degrees of freedom and give explicitly the propagation matrix that
replaces the effective sound speed of the one-dimensional case. We then examine
in detail the consequences of a sudden turn along the inflationary trajectory,
in particular the possible breakdown of the low energy effective theory in case
the heavy modes are excited. Resorting to a new basis in field space, instead
of the usual adiabatic/entropic basis, we study the evolution of the
perturbations during the turn. In particular, we compute the power spectrum and
compare with the result obtained from the low energy effective theory.Comment: 24 pages, 13 figures; v2 substantial changes in sec.V; v3 matching
the published version on JCA
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