74 research outputs found
Intertwined superfluid and density wave order in two-dimensional 4He
Superfluidity is a manifestation of the operation of the laws of quantum mechanics on a macroscopic scale. The conditions under which superfluidity becomes manifest have been extensively explored experimentally in both quantum liquids (liquid 4He being the canonical example) and ultracold atomic gases1, 2, including as a function of dimensionality3, 4. Of particular interest is the hitherto unresolved question of whether a solid can be superfluid5, 6. Here we report the identification of a new state of quantum matter with intertwined superfluid and density wave order in a system of two-dimensional bosons subject to a triangular lattice potential. Using a torsional oscillator we have measured the superfluid response of the second atomic layer of 4He adsorbed on the surface of graphite, over a wide temperature range down to 2 mK. Superfluidity is observed over a narrow range of film densities, emerging suddenly and subsequently collapsing towards a quantum critical point. The unusual temperature dependence of the superfluid density in the limit of zero temperature and the absence of a clear superfluid onset temperature are explained, self-consistently, by an ansatz for the excitation spectrum, reflecting density wave order, and a quasi-condensate wavefunction breaking both gauge and translational symmetry
Type D Personality, Temperament, and Mental Health in Military Personnel Awaiting Deployment
Type D personality, temperament, and mental health in military personnel awaitin
Impact of social integration on metabolic functions: evidence from a nationally representative longitudinal study of US older adults
BACKGROUND: Metabolic functions may operate as important biophysiological mechanisms through which social relationships affect health. It is unclear how social embeddedness or the lack thereof is related to risk of metabolic dysregulation. To fill this gap we tested the effects of social integration on metabolic functions over time in a nationally representative sample of older adults in the United States and examined population heterogeneity in the effects. METHODS: Using longitudinal data from 4,323 adults aged over 50 years in the Health and Retirement Study and latent growth curve models, we estimated the trajectories of social integration spanning five waves, 1998–2006, in relation to biomarkers of energy metabolism in 2006. We assessed social integration using a summary index of the number of social ties across five domains. We examined six biomarkers, including total cholesterol, high-density lipoprotein cholesterol, glycosylated hemoglobin, waist circumference, and systolic and diastolic blood pressure, and the summary index of the overall burden of metabolic dysregulation. RESULTS: High social integration predicted significantly lower risks of both individual and overall metabolic dysregulation. Specifically, adjusting for age, sex, race, and body mass index, having four to five social ties reduced the risks of abdominal obesity by 61% (odds ratio [OR] [95% confidence interval {CI}] = 0.39 [0.23, 0.67], p = .007), hypertension by 41% (OR [95% CI] = 0.59 [0.42, 0.84], p = .021), and the overall metabolic dysregulation by 46% (OR [95% CI] = 0.54 [0.40, 0.72], p < .001). The OR for the overall burden remained significant when adjusting for social, behavioral, and illness factors. In addition, stably high social integration had more potent metabolic impacts over time than changes therein. Such effects were consistent across subpopulations and more salient for the younger old (those under age 65), males, whites, and the socioeconomically disadvantaged. CONCLUSIONS: This study addressed important challenges in previous research linking social integration to metabolic health by clarifying the nature and direction of the relationship as it applies to different objectively measured markers and population subgroups. It suggests additional psychosocial and biological pathways to consider in future research on the contributions of social deficits to disease etiology and old-age mortality
Multi-center, randomized, placebo-controlled trial of nocturnal oxygen therapy in chronic obstructive pulmonary disease: a study protocol for the INOX trial
Beta-HPV 5 and 8 E6 Promote p300 Degradation by Blocking AKT/p300 Association
The E6 oncoprotein from high-risk genus alpha human papillomaviruses (α-HPVs), such as HPV 16, has been well characterized with respect to the host-cell proteins it interacts with and corresponding signaling pathways that are disrupted due to these interactions. Less is known regarding the interacting partners of E6 from the genus beta papillomaviruses (β-HPVs); however, it is generally thought that β-HPV E6 proteins do not interact with many of the proteins known to bind to α-HPV E6. Here we identify p300 as a protein that interacts directly with E6 from both α- and β-HPV types. Importantly, this association appears much stronger with β-HPV types 5 and 8-E6 than with α-HPV type 16-E6 or β-HPV type 38-E6. We demonstrate that the enhanced association between 5/8-E6 and p300 leads to p300 degradation in a proteasomal-dependent but E6AP-independent manner. Rather, 5/8-E6 inhibit the association of AKT with p300, an event necessary to ensure p300 stability within the cell. Finally, we demonstrate that the decreased p300 protein levels concomitantly affect downstream signaling events, such as the expression of differentiation markers K1, K10 and Involucrin. Together, these results demonstrate a unique way in which β-HPV E6 proteins are able to affect host-cell signaling in a manner distinct from that of the α-HPVs
Basic science of osteoarthritis
Osteoarthritis (OA) is a prevalent, disabling disorder of the joints that affects a large population worldwide and for which there is no definitive cure. This review provides critical insights into the basic knowledge on OA that may lead to innovative end efficient new therapeutic regimens. While degradation of the articular cartilage is the hallmark of OA, with altered interactions between chondrocytes and compounds of the extracellular matrix, the subchondral bone has been also described as a key component of the disease, involving specific pathomechanisms controlling its initiation and progression. The identification of such events (and thus of possible targets for therapy) has been made possible by the availability of a number of animal models that aim at reproducing the human pathology, in particular large models of high tibial osteotomy (HTO). From a therapeutic point of view, mesenchymal stem cells (MSCs) represent a promising option for the treatment of OA and may be used concomitantly with functional substitutes integrating scaffolds and drugs/growth factors in tissue engineering setups. Altogether, these advances in the fundamental and experimental knowledge on OA may allow for the generation of improved, adapted therapeutic regimens to treat human OA.(undefined
Uniendo ingeniería y ecología: la protección costera basada en ecosistemas
En un contexto de crecientes impactos y riesgos socio-económicos en las costas del planeta, la
protección costera basada en ecosistemas surge como un nuevo paradigma que une los principios
de protección, sostenibilidad y resiliencia, a la vez que proporciona múltiples beneficios. Este
artículo ofrece una perspectiva sobre qué son y cómo se pueden utilizar las defensas naturales en
el diseño, planificación y gestión de costas. La política pública muestra un creciente interés por su
implementación general y el cuerpo de conocimiento y experiencia alrededor de la también
denominada infraestructura ?verde? es creciente, pero aún existen importantes barreras que
salvar. Una de ellas es estandarizar su diseño en términos ingenieriles, así como reconocer los
aspectos que los diferencian respecto a enfoques tradicionales. La adaptación climática y la
reducción de riesgos son áreas en las que su utilización puede ser más significativa, debido a
la variedad de servicios que ofrecen. Tanto desde el punto de vista técnico como económico,
existen argumentos sólidos para evitar la degradación de los ecosistemas, avanzando su
restauración y conservación, como también desde la perspectiva de la defensa de las costas.In a context of increasing socio-economic impacts and risks in the coastal areas of the planet,
coastal protection based on ecosystem features becomes a new paradigm that combines the
principles of conservation, sustainability and resilience, while providing multiple benefits. This
paper provides a perspective on what these are and how they can be used in the design,
planning and management of the coastal zones. Policy-makers are calling for further uptake
and implementation across the board and the body of knowledge and experience around the socalled
?green? infrastructure is growing, but there are still major barriers for a widespread uptake.
One of them is to standardize designs in engineering terms, recognizing the different characteristics
compared to traditional engineering solutions. Climate adaptation and risk reduction are
areas where its use may be more significant, for the variety of services they offer. Both technically
and economically, there are strong arguments to prevent degradation of ecosystems and to
advance in their restoration and conservation, as well as from a coastal defense perspective
Dimensional crossover and cold-atom realization of topological Mott insulators
Interacting cold-atomic gases in optical lattices offer an experimental approach to outstanding problems of many body physics. One important example is the interplay of interaction and topology which promises to generate a variety of exotic phases such as the fractionalized Chern insulator or the topological Mott insulator. Both theoretically understanding these states of matter and finding suitable systems that host them have proven to be challenging problems. Here we propose a cold-atom setup where Hubbard on-site interactions give rise to spin liquid-like phases: weak and strong topological Mott insulators. They represent the celebrated paradigm of an interacting and topological quantum state with fractionalized spinon excitations that inherit the topology of the non-interacting system. Our proposal shall help to pave the way for a controlled experimental investigation of this exotic state of matter in optical lattices. Furthermore, it allows for the investigation of a dimensional crossover from a two-dimensional quantum spin Hall insulating phase to a three-dimensional strong topological insulator by tuning the hopping between the layers
- …