4,219 research outputs found
Environmental economics and the Murray–Darling: Comment
Resource /Energy Economics and Policy,
Study of pharmaceutical industrial problems
The growth of a human colon carcinoma cell line (SK-CO-1) and its production of carcinoembryonic antigen (CEA) in monolayer culture and on single layers of glass beads in unit gravity were evaluated. The limitations of using a microsphere-cell growth system in unit gravity were identified and how these may be overcome in space was considered. The project had the following tasks: (1) growth of cultured human colon carcinoma cells on a monolayer and CEA production; (2) evaluation of CEA production and release by SK-CO-1 cells grown on glass beads; (3) evaluation of other microcarriers for growing SK-CO-1 cells and determination of the minimum amount of culture medium needed for cell growth; and (4) growth of SK-CO-1 cells on collagen monolayers and CEA production
Polyelectrolyte-colloid complexes: polarizability and effective interaction
We theoretically study the polarizability and the interactions of neutral
complexes consisting of a semi-flexible polyelectrolyte adsorbed onto an
oppositely charged spherical colloid. In the systems we studied, the bending
energy of the chain is small compared to the Coulomb energy and the chains are
always adsorbed on the colloid. We observe that the polarizability is large for
short chains and small electrical fields and shows a non-monotonic behavior
with the chain length at fixed charge density. The polarizability has a maximum
for a chain length equal to half of the circumference of the colloid. For long
chains we recover the polarizability of a classical conducting sphere. For
short chains, the existence of a permanent dipole moment of the complexes leads
to a van der Waal's-type long-range attraction between them. This attractive
interaction vanishes for long chains (i.e., larger than the colloidal size),
where the permanent dipole moment is negligible. For short distances the
complexes interact with a deep short-ranged attraction which is due to
energetic bridging for short chains and entropic bridging for long chains.
Exceeding a critical chain length eventually leads to a pure repulsion. This
shows that the stabilization of colloidal suspensions by polyelectrolyte
adsorption is strongly dependent on the chain size relative to the colloidal
size: for long chains the suspensions are always stable (only repulsive forces
between the particles), while for mid-sized and short chains there is
attraction between the complexes and a salting-out can occur.Comment: 13 pages, 14 figure
A microRNA feedback loop regulates global microRNA abundance during aging
Expression levels of many microRNAs (miRNAs) change during aging, notably declining globally in a number of organisms and tissues across taxa. However, little is known about the mechanisms or the biological relevance for this change. We investigated the network of genes that controls miRNA transcription and processing during C. elegans aging. We found that miRNA biogenesis genes are highly networked with transcription factors and aging-associated miRNAs. In particular, miR-71, known to influence life span and itself up-regulated during aging, represses alg-1/Argonaute expression post-transcriptionally during aging. Increased ALG-1 abundance in mir-71 loss-of-function mutants led to globally increased miRNA expression. Interestingly, these mutants demonstrated widespread mRNA expression dysregulation and diminished levels of variability both in gene expression and in overall life span. Thus, the progressive molecular decline often thought to be the result of accumulated damage over an organism's life may be partially explained by a miRNA-directed mechanism of age-associated decline.</jats:p
The Fifteenth Annual Albert A. DeStefano Lecture On Corporate, Securities, & Financial Law At The Fordham Corporate Law Center
Fiscal Equity In Federal Systems
This paper examines the normative foundations of fiscal equalization an issue handled, apparently decisively, in a classic paper by James Buchanan (1950). Contrary to Buchanan's claims, we argue that fiscal equalization requires extremely strong value judgements at least in the case where fiscal differences arise from the interaction of public goods provision under different population size effectively committing one to a Rawlsian maximin rule. Much weaker forms of the 'social welfare function' in this public goods case will generate the requirement that private consumption levels be equalized, but specifically not public consumption levels in which sense private goods equalization seems normatively weaker than public goods equalization, If this is so, the hope of justifying federal fiscal equalization on the basis of relatively uncontroversial individualistic norms seems illusory
Transcriptional (dys)regulation and aging in Caenorhabditis elegans
New work could link laboratory-defined longevity pathways to the process of normal aging
Pain management for chronic musculoskeletal conditions : the development of an evidence-based and theory-informed pain self-management course
Objective: To devise and test a self-management course for chronic pain patients based on evidence and underpinned by theory using the Medical Research Council (MRC) framework for developing complex interventions.
Design: We used a mixed method approach. We conducted a systematic review of the effectiveness of components and characteristics of pain management courses. We then interviewed chronic pain patients who had attended pain and self-management courses. Behavioural change theories were mapped onto our findings and used to design the intervention. We then conducted a feasibility study to test the intervention.
Setting: Primary care in the inner city of London, UK.
Participants: Adults (18 years or older) with chronic musculoskeletal pain.
Outcomes: Related disability, quality of life, coping, depression, anxiety, social integration and healthcare resource use.
Results: The systematic reviews indicated that group-based courses with joint lay and healthcare professional leadership and that included a psychological component of short duration (<8 weeks) showed considerable promise. The qualitative research indicated that participants liked relaxation, valued social interaction and course location, and that timing and good tutoring were important determinants of attendance. We used behavioural change theories (social learning theory and cognitive behaviour approaches (CBA)) to inform course content. The course addressed: understanding and accepting pain, mood and pain, unhelpful thoughts and behaviour, problem solving, goal setting, action planning, movement, relaxation and social integration/reactivation. Attendance was 85%; we modified the recruitment of patients, the course and the training of facilitators as a result of testing.
Conclusions: The MRC guidelines were helpful in developing this intervention. It was possible to train both lay and non-psychologists to facilitate the courses and deliver CBA. The course was feasible and well received
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