3,149 research outputs found
Hispanic Familism Reconsidered
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93710/1/tsq1252.pd
Preparation of atomically clean and flat Si(100) surfaces by low-energy ion sputtering and low-temperature annealing
Si(100) surfaces were prepared by wet-chemical etching followed by 0.3-1.5keV
Ar ion sputtering, either at elevated or room temperature. After a brief anneal
under ultrahigh vacuum conditions, the resulting surfaces were examined by
scanning tunneling microscopy. We find that wet-chemical etching alone cannot
produce a clean and flat Si(100) surface. However, subsequent 300eV Ar ion
sputtering at room temperature followed by a 973K anneal yields atomically
clean and flat Si(100) surfaces suitable for nanoscale device fabrication.Comment: 13 pages, 3 figures, to be published in Applied Surface Scienc
Unfitness to Plead. Volume 1: Report.
This has been produced along with Volume 2: Draft Legislation as a combined document
Presented to Parliament pursuant to section 3(2) of the Law Commissions Act 1965
Ordered by the House of Commons to be printed on 12 January 201
Kination Dominated Reheating and Cold Dark Matter Abundance
We consider the decay of a massive particle under the complete or partial
domination of the kinetic energy density generated by a quintessential
exponential model and we impose a number of observational constraints
originating from nucleosynthesis, the present acceleration of the universe and
the dark-energy-density parameter. We show that the presence of kination causes
a prolonged period during which the temperature is frozen to a plateau value,
much lower than the maximal temperature achieved during the process of
reheating in the absence of kination. The decoupling of a cold dark matter
particle during this period is analyzed, its relic density is calculated both
numerically and semi-analytically and the results are compared with each other.
Using plausible values (from the viewpoint of particle models) for the mass and
the thermal averaged cross section times the velocity of the cold relic, we
investigate scenaria of equilibrium or non-equilibrium production. In both
cases, acceptable results for the cold dark matter abundance can be obtained,
by constraining the initial energy density of the decaying particle, its decay
width, its mass and the averaged number of the produced cold relics. The
required plateau value of the temperature is, in most cases, lower than about
40 GeVComment: Final versio
The Impact of Quantitative Easing on UK Bank Lending: Why Banks Do Not Lend to Businesses?
The growing proportion of UK bank lending to the financial sector reached a peak in 2007 just before the onset of the Global Financial Crisis (GFC). This marks a trend in the dwindling amount of bank lending to private sector non-financial corporations (PNFCs), which was exacerbated with the Great Recession. Many central banks aimed to revive bank lending with quantitative easing (QE) and unconventional monetary policy. We propose an agent based computational economics (ACE) model which combines the main factors in the economic environment of QE and Basel regulatory framework to analyse why UK banks do not prioritize lending to non-financial businesses. The lower bond yields caused by QE encourage big firms to substitute away from bank borrowing to bond issuance. In addition, the risk weight regime of Basel I/II on capital induces banks to favour mortgages over business loans to small and medium enterprises (SMEs). The combination of lower bond yields and Basel II/III capital requirements on banks, which, respectively, impact demand and supply of credit in the UK, plays a role in the drop of bank loans to businesses. The ACE model aims to reinstate policy regimes that form constraints and incentives for the behaviour of market participants to provide the causal factors in observed macro-economic phenomena
Caenorhabditis elegans orthologs of human genes differentially expressed with age are enriched for determinants of longevity
We report a systematic RNAi longevity screen of 82 Caenorhabditis elegans genes selected based on orthology to human genes differentially expressed with age. We find substantial enrichment in genes for which knockdown increased lifespan. This enrichment is markedly higher than published genomewide longevity screens in C. elegans and similar to screens that preselected candidates based on longevity-correlated metrics (e.g., stress resistance). Of the 50 genes that affected lifespan, 46 were previously unreported. The five genes with the greatest impact on lifespan (>20% extension) encode the enzyme kynureninase (kynu-1), a neuronal leucine-rich repeat protein (iglr-1), a tetraspanin (tsp-3), a regulator of calcineurin (rcan-1), and a voltage-gated calcium channel subunit (unc-36). Knockdown of each gene extended healthspan without impairing reproduction. kynu-1(RNAi) alone delayed pathology in C. elegans models of Alzheimer's disease and Huntington's disease. Each gene displayed a distinct pattern of interaction with known aging pathways. In the context of published work, kynu-1, tsp-3, and rcan-1 are of particular interest for immediate follow-up. kynu-1 is an understudied member of the kynurenine metabolic pathway with a mechanistically distinct impact on lifespan. Our data suggest that tsp-3 is a novel modulator of hypoxic signaling and rcan-1 is a context-specific calcineurin regulator. Our results validate C. elegans as a comparative tool for prioritizing human candidate aging genes, confirm age-associated gene expression data as valuable source of novel longevity determinants, and prioritize select genes for mechanistic follow-up
The Rourke Baby Record Infant/Child Maintenance Guide: do doctors use it, do they find it useful, and does using it improve their well-baby visit records?
Background. The Rourke Baby Record (RBR) - http://www.rourkebabyrecord.ca - is a freely available evidence-based structured form for child health surveillance from zero to five years. Family physicians/general practitioners (FP/GPs) doing office based well-baby care in three Ontario Canada cities (London, Ottawa, and Toronto) were randomly sampled to study the prevalence and utility of the RBR and documentation of well-baby visits. Methods. Database with telephone confirmation was conducted to assess the prevalence of use of the RBR. Study Part 1: Questionnaire mailed to a random sample of 100 RBR users. Outcome measures were utility of, helpfulness of, and suggestions for the RBR. Descriptive analysis was employed. Study Part 2: Retrospective chart review of well-baby visits by 38 FP/GPs using student t-tests and factor analysis. Outcome measures were well-baby visit documentation of growth, nutrition, safety issues, developmental milestones, physical examination, and overall comprehensiveness. Results. The RBR was used by 78.5% (402/512) of successfully contacted FP/GPs who did well-baby care in these 3 cities. Study Part 1: Questionnaire respondents (N = 41/100) used the RBR in several ways, and found it most helpful for assessing healthy child development, charting/recording the visits, managing time effectively, addressing parent concerns, identifying health problems, and identifying high risk situations. The RBR was seen to be least helpful as a tool for managing or for referring identified health problems. Study Part 2: Charts from a total of 1,378 well-baby visits on 176 children were audited. Well-baby care provided by the 20 FP/GPs who used the RBR compared to that by the 18 non-users was statistically more likely to include documentation of type of feeding (p = 0.023), discussion of safety issues (p < 0.001), assessment of development (p = 0.001), and overall comprehensiveness (p < 0.001). Well-baby care provided by the RBR users compared to that by the non-users was not more likely to include documentation of measurement of growth (p = 0.097), or physical examination (p = 0.828). Conclusion. The RBR was widely used by FP/GPs in these settings. RBR users found it helpful for many purposes, and had a consistently high rate of documentation of many aspects of well-baby care. The Rourke Baby Record has become a de facto gold standard clinical practice tool in knowledge translation for pediatric preventive medicine and health surveillance for primary care pediatric providers
On the Free Energy That Drove Primordial Anabolism
A key problem in understanding the origin of life is to explain the mechanism(s) that led to the spontaneous assembly of molecular building blocks that ultimately resulted in the appearance of macromolecular structures as they are known in modern biochemistry today. An indispensable thermodynamic prerequisite for such a primordial anabolism is the mechanistic coupling to processes that supplied the free energy required. Here I review different sources of free energy and discuss the potential of each form having been involved in the very first anabolic reactions that were fundamental to increase molecular complexity and thus were essential for life
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