2,686 research outputs found
Social Reproduction and Depletion
Social reproduction is not costless. When unrecognised, valorised but not valued, social reproduction leads to depletion of those who care. Building on the arguments of feminist international political economists, I examine the importance of taking the work of care seriously. Depletion through social reproduction occurs when resources for social reproduction fall below a threshold of sustainability over time. To know the intensity and extensity of depletion allows us to reveal not only the distress – physical, emotional/mental and social - but also to strategise towards reversing depletion
Deep Gated Hebbian Predictive Coding Accounts for Emergence of Complex Neural Response Properties Along the Visual Cortical Hierarchy
Predictive coding provides a computational paradigm for modeling perceptual processing as the construction of representations accounting for causes of sensory inputs. Here, we developed a scalable, deep network architecture for predictive coding that is trained using a gated Hebbian learning rule and mimics the feedforward and feedback connectivity of the cortex. After training on image datasets, the models formed latent representations in higher areas that allowed reconstruction of the original images. We analyzed low- and high-level properties such as orientation selectivity, object selectivity and sparseness of neuronal populations in the model. As reported experimentally, image selectivity increased systematically across ascending areas in the model hierarchy. Depending on the strength of regularization factors, sparseness also increased from lower to higher areas. The results suggest a rationale as to why experimental results on sparseness across the cortical hierarchy have been inconsistent. Finally, representations for different object classes became more distinguishable from lower to higher areas. Thus, deep neural networks trained using a gated Hebbian formulation of predictive coding can reproduce several properties associated with neuronal responses along the visual cortical hierarchy
Superconductor Insulator Transition in Long MoGe Nanowires
Properties of one-dimensional superconducting wires depend on physical
processes with different characteristic lengths. To identify the process
dominant in the critical regime we have studied trans- port properties of very
narrow (9-20 nm) MoGe wires fabricated by advanced electron-beam lithography in
wide range of lengths, 1-25 microns. We observed that the wires undergo a
superconductor -insulator transition that is controlled by cross sectional area
of a wire and possibly also by the thickness-to-width ratio. Mean-field
critical temperature decreases exponentially with the inverse of the wire cross
section. We observed that qualitatively similar superconductor{insulator
transition can be induced by external magnetic field. Some of our long
superconducting MoGe nanowires can be identified as localized superconductors,
namely in these wires one-electron localization length is much shorter than the
length of a wire
Recommended from our members
Language and Reading Progress of Young Deaf and Hard-of-Hearing Children.
We examined the language and reading progress of 336 young DHH children in kindergarten, first and second grades. Trained assessors tested children's language, reading, and spoken and fingerspelled phonological awareness in the fall and spring of the school year. Children were divided into groups based on their auditory access and classroom communication: a spoken-only group (n = 101), a sign-only group (n = 131), and a bimodal group (n = 104). Overall, children showed delays in language and reading compared to norms established for hearing children. For language, vocabulary standard scores were higher than for English syntax. Although delayed in language, children made expected gains based on hearing norms from kindergarten to second grade. Reading scores declined from kindergarten to second grade. Spoken-only and bimodal children had similar word reading and reading comprehension abilities and higher scores than sign-only children. Spoken-only children had better spoken phonological awareness and nonword reading skills than the other two groups. The sign-only and bimodal groups made similar and significant gains in ASL syntax and fingerspelling phonological awareness
The anti-cancer effect of retinoic acid signaling in CRC occurs via decreased growth of ALDH+ colon cancer stem cells and increased differentiation of stem cells
Background: Tumorigenesis is driven by stem cell (SC) overpopulation. BecauseALDH is both a marker for SCs in many tissues and a key enzyme in retinoid acid (RA)signaling, we studied RA signaling in normal and malignant colonic SCs.Hypothesis: RA signaling regulates growth and differentiation of ALDH+ colonicSCs dysregulation of RA signaling contributes to SC overpopulation and colorectalcancer (CRC) development.Methods: We analyzed normal and malignant colonic tissues and CRC cell linesto see if retinoid receptors (RXR &RAR) are exclusively expressed in ALDH+ SCs,and if RA signaling changes during CRC development. We determined whether RAsignaling regulates cancer SC (CSC) proliferation, differentiation, sphere formation,and population size.Results: RXR &RAR were expressed in ALDH+ colonic SCs, but not in MCM2+proliferative cells. Western blotting/immunostaining of CRCs revealed that RAsignaling components become overexpressed in parallel with ALDH overexpression,which coincides with the known overpopulation of ALDH+ SCs that occurs during,and drives, CRC development. Treatment of SCs with all-trans retinoic acid (ATRA)decreased proliferation, sphere formation and ALDH+ SC population size, and induceddifferentiation along the neuroendocrine cell (NEC) lineage.Conclusions: Retinoid signaling, by regulating ALDH+ colonic CSCs, decreases SCproliferation, sphere formation, and population size, and increases SC differentiation toNECs. Dysregulation of RA signaling in colonic SCs likely contributes to overpopulationof ALDH+ SCs and CRC growth.Implications: That retinoid receptors RXR and RAR are selectively expressed inALDH+ SCs indicates RA signaling mainly occurs via ALDH+ SCs, which provides amechanism to selectively target CSCs. © 2018 Impact Journals LLC. All rights reserved
Effect of Non-Rubber Constituents on Guayule and Hevea Rubber Intrinsic Properties
To meet the increasing demand for natural rubber (NR), currently sourced from the tropical rubber tree Hevea brasiliensis, and address price volatility and steadily increasing labor costs, alternate rubber-producing species are in commercial development. One of these, guayule (Parthenium argentatum), has emerged on the market as a commercial source of high quality rubber. Non-rubber constituents play an important role in the physical properties of NR products. The intrinsic composition of the two NR materials differs and these differences may be a principal cause of the performance differences between them.We have compared the effect of non-rubber constituents, such as protein, lipids, resin and rubber particle membranes. Firstly, a film casting method was developed to obtain rubber films with a uniform thickness. Secondly, the glass transition temperature of different rubbers was determined by dynamic mechanical analysis, and tensile properties were tested for uncompounded materials. Guayule natural rubber (GNR), from which most of the membranes were removed while in latex form (MRGNR) was found to have higher intrinsic strength than GNR or gel-free NR (FNR). An acetone extraction was performed to quantify the resin and free lipids in the rubber samples
Depression Affects Recovery Following Distal Radius Fracture: A Latent Class Analysis
Background: Most people recover within six months following distal radius fractures (DRFs) but some experience pain and disability for one year or longer. Therefore, it is important to understand the factors that can help predict recovery. According to the biopsychosocial model of pain, psychological aspects of a condition can play important roles in explaining recovery.
Objectives: To identify the recovery trajectories of patients with DRFs and to determine the degree to which depression affects these trajectories.
Methods: Recovery was assessed in 318 patients using the Patient-Rated Wrist Evaluation scale at baseline, three, six, and 12 months. Demographic information was collected in addition to the Self-Administered Comorbidity Questionnaire, from which data regarding the single item pertaining to depression were extracted. Latent class analysis was used to identify the recovery trajectories. Comparisons of proportion between the emergent classes were then conducted using chi-square and Kruskal-Wallis tests.
Results: The latent class analysis revealed three trajectories: rapid-recovery, slow-recovery, and non-recovery as the best fit to the data. The proportion of people that had depression was significantly greater in the non-recovery class (24%) compared to the rapid-recovery (8%) and slow-recovery classes (16%) (p
Discussion: Patients who appear to be in the non-recovery class may require additional assessments, closer monitoring, supervised therapy, or other interventions to improve outcomes
Separating hyperfine from spin-orbit interactions in organic semiconductors by multi-octave magnetic resonance using coplanar waveguide microresonators
Separating the influence of hyperfine from spin-orbit interactions in
spin-dependent carrier recombination and dissociation processes necessitates
magnetic resonance spectroscopy over a wide range of frequencies. We have
designed compact and versatile coplanar waveguide resonators for
continuous-wave electrically detected magnetic resonance, and tested these on
organic light-emitting diodes. By exploiting both the fundamental and
higher-harmonic modes of the resonators we cover almost five octaves in
resonance frequency within a single setup. The measurements with a common
pi-conjugated polymer as the active material reveal small but non-negligible
effects of spin-orbit interactions, which give rise to a broadening of the
magnetic resonance spectrum with increasing frequency
- …