896 research outputs found
Lower body design of the βiCubβ a human-baby like crawling robot
The development of robotic cognition and a greater understanding of human cognition form two of the current greatest challenges of science. Within the RobotCub project the goal is the development of an embodied robotic child (iCub) with the physical and ultimately cognitive abilities of a 2frac12 year old human baby. The ultimate goal of this project is to provide the cognition research community with an open human like platform for understanding of cognitive systems through the study of cognitive development. In this paper the design of the mechanisms adopted for lower body and particularly for the leg and the waist are outlined. This is accompanied by discussion on the actuator group realisation in order to meet the torque requirements while achieving the dimensional and weight specifications. Estimated performance measures of the iCub are presented
Causes of Higher Climate Sensitivity in CMIP6 Models
Equilibrium climate sensitivity, the global surface temperature response to CO urn:x-wiley:grl:media:grl60047:grl60047-math-0001 doubling, has been persistently uncertain. Recent consensus places it likely within 1.5β4.5 K. Global climate models (GCMs), which attempt to represent all relevant physical processes, provide the most direct means of estimating climate sensitivity via CO urn:x-wiley:grl:media:grl60047:grl60047-math-0002 quadrupling experiments. Here we show that the closely related effective climate sensitivity has increased substantially in Coupled Model Intercomparison Project phase 6 (CMIP6), with values spanning 1.8β5.6 K across 27 GCMs and exceeding 4.5 K in 10 of them. This (statistically insignificant) increase is primarily due to stronger positive cloud feedbacks from decreasing extratropical low cloud coverage and albedo. Both of these are tied to the physical representation of clouds which in CMIP6 models lead to weaker responses of extratropical low cloud cover and water content to unforced variations in surface temperature. Establishing the plausibility of these higher sensitivity models is imperative given their implied societal ramifications
Prospective Study Evaluating Management of Hypertension Induced by anti-VEGF Therapy in Patients with Active Cancer: VEGFHTN Trial
https://openworks.mdanderson.org/sumexp23/1027/thumbnail.jp
Scale Dependence of Dark Energy Antigravity
We investigate the effects of negative pressure induced by dark energy
(cosmological constant or quintessence) on the dynamics at various
astrophysical scales. Negative pressure induces a repulsive term (antigravity)
in Newton's law which dominates on large scales. Assuming a value of the
cosmological constant consistent with the recent SnIa data we determine the
critical scale beyond which antigravity dominates the dynamics () and discuss some of the dynamical effects implied. We show that
dynamically induced mass estimates on the scale of the Local Group and beyond
are significantly modified due to negative pressure. We also briefly discuss
possible dynamical tests (eg effects on local Hubble flow) that can be applied
on relatively small scales (a few ) to determine the density and equation
of state of dark energy.Comment: Contributed talk at the 2nd Hellenic Cosmology Workshop at NOA
(Athens) Jan. 2001.To appear in the proceedings. Based on work done in
collaboration with M. Axenides and E. Florato
Recommended from our members
The Development of a Set of Principles for Through-Life Management of Engineering Information
Corporate business models are shifting away from product delivery paradigms to product-service paradigms, where ongoing through-life service support is preeminent. In the UK, a Grand Challenge project (www.kimproject.org) was established to investigate and develop good practice with regard to the design and use of information, knowledge support systems, and business methods necessary for organisations to succeed and profit within this new environment. A key outcome of this work has been the development of a series of principles for through-life management of
engineering information, derived from the research insights and experiences of project members in both academia and industry, and supported by detailed explanations and implementation guidance. This report is an approved version of the Principles and their development.This work was undertaken through the βImmortal Information and Through-Life Knowledge Management: Strategies and Tools for the Emerging Product-Service Paradigmβ (KIM) project, funded by the UK Engineering and Physical Sciences Research Council (EPSRC) and the Economic and Social Research Council (ESRC), under grant number EP/C534220/1
Do Observations Favour Galileon Over Quintessence?
We study the Galileon scalar field model arising as a decoupling limit of the
Dvali-Gababdaze-Porrati (DGP) construction for the late time acceleration of
the universe. The model has one extra Galileon correction term over and above
the standard kinetic and potential energy terms for a canonical quintessence
field. We aim to study whether the current observational data can distinguish
between this Galileon field and the quintessence field. Our study shows the
remarkable result that for potentials like linear, square or exponential, the
data prefers the Galileon model over quintessence field. It confirms that the
observable universe demands the inclusion of higher derivative Galileon
corrections in the standard quintessence scalar field models.Comment: 5 pages, Revtex style, three eps figures, revised version with new
comments added. Conclusion is unchange
The Effect of Epstein-Barr Virus Latent Membrane Protein 2 Expression on the Kinetics of Early B Cell Infection
Infection of human B cells with wild-type Epstein-Barr virus (EBV) in vitro leads to activation and proliferation that result in efficient production of lymphoblastoid cell lines (LCLs). Latent Membrane Protein 2 (LMP2) is expressed early after infection and previous research has suggested a possible role in this process. Therefore, we generated recombinant EBV with knockouts of either or both protein isoforms, LMP2A and LMP2B (Ξ2A, Ξ2B, Ξ2A/Ξ2B) to study the effect of LMP2 in early B cell infection. Infection of B cells with Ξ2A and Ξ2A/Ξ2B viruses led to a marked decrease in activation and proliferation relative to wild-type (wt) viruses, and resulted in higher percentages of apoptotic B cells. Ξ2B virus infection showed activation levels comparable to wt, but fewer numbers of proliferating B cells. Early B cell infection with wt, Ξ2A and Ξ2B viruses did not result in changes in latent gene expression, with the exception of elevated LMP2B transcript in Ξ2A virus infection. Infection with Ξ2A and Ξ2B viruses did not affect viral latency, determined by changes in LMP1/Zebra expression following BCR stimulation. However, BCR stimulation of Ξ2A/Ξ2B cells resulted in decreased LMP1 expression, which suggests loss of stability in viral latency. Long-term outgrowth assays revealed that LMP2A, but not LMP2B, is critical for efficient long-term growth of B cells in vitro. The lowest levels of activation, proliferation, and LCL formation were observed when both isoforms were deleted. These results suggest that LMP2A appears to be critical for efficient activation, proliferation and survival of EBV-infected B cells at early times after infection, which impacts the efficient long-term growth of B cells in culture. In contrast, LMP2B did not appear to play a significant role in these processes, and long-term growth of infected B cells was not affected by the absence of this protein. Β© 2013 Wasil et al
Study protocol to investigate the effect of a lifestyle intervention on body weight, psychological health status and risk factors associated with disease recurrence in women recovering from breast cancer treatment
Background
Breast cancer survivors often encounter physiological and psychological problems related to their diagnosis and treatment that can influence long-term prognosis. The aim of this research is to investigate the effects of a lifestyle intervention on body weight and psychological well-being in women recovering from breast cancer treatment, and to determine the relationship between changes in these variables and biomarkers associated with disease recurrence and survival.
Methods/design
Following ethical approval, a total of 100 patients will be randomly assigned to a lifestyle intervention (incorporating dietary energy restriction in conjunction with aerobic exercise training) or normal care control group. Patients randomised to the dietary and exercise intervention will be given individualised healthy eating dietary advice and written information and attend moderate intensity aerobic exercise sessions on three to five days per week for a period of 24 weeks. The aim of this strategy is to induce a steady weight loss of up to 0.5 Kg each week. In addition, the overall quality of the diet will be examined with a view to (i) reducing the dietary intake of fat to ~25% of the total calories, (ii) eating at least 5 portions of fruit and vegetables a day, (iii) increasing the intake of fibre and reducing refined carbohydrates, and (iv) taking moderate amounts of alcohol. Outcome measures will include body weight and body composition, psychological health status (stress and depression), cardiorespiratory fitness and quality of life. In addition, biomarkers associated with disease recurrence, including stress hormones, estrogen status, inflammatory markers and indices of innate and adaptive immune function will be monitored.
Discussion
This research will provide valuable information on the effectiveness of a practical, easily implemented lifestyle intervention for evoking positive effects on body weight and psychological well-being, two important factors that can influence long-term prognosis in breast cancer survivors. However, the added value of the study is that it will also evaluate the effects of the lifestyle intervention on a range of biomarkers associated with disease recurrence and survival. Considered together, the results should improve our understanding of the potential role that lifestyle-modifiable factors could play in saving or prolonging lives
Enteric Neurospheres Are Not Specific to Neural Crest Cultures: Implications for Neural Stem Cell Therapies
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited
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