Scattering of 3MEV neutrons from heavy nuclei

SIGLEAvailable from British Library Document Supply Centre- DSC:D44301/83 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

U.S. public and private venture capital markets, 1998-2001: A fundamental information analysis

Systematic analysis of U.S. capital markets reveals important empirical facts that analytical modeling or empirical research seeking to explain the 1998-2001 movements needs to recognize. There is no single "bubble point" at which U.S. capital markets had an epiphany that valuations required a sharp downward re-evaluation. Rather, different sectors had different points after which ex post sustained declines occurred. For the NASDAQ/NYSE/AMEX public capital markets, the sustained ex post declines occurred starting in March 2000 for the computer software industry and in September 2000 for the computer hardware industry. Private venture capital investment in new ventures peaked in the March 2000 quarter for software and in the September 2000 quarter for hardware and communications. Four sectors exhibiting extreme price movements are identified - computer hardware, computer software, telecommunications, and biotech/pharmaceuticals. These sectors had observable characteristics prior to 1998 that implied higher risk - they had higher relative risk (CAPM beta), higher standard deviation of security returns, more extreme revenue growth increases (decreases) in the upper (lower) tails, and a higher propensity for negative net income. During the 1998-2001 period, companies in these sectors had abnormally high revenue growth rates. An Internet sample of companies exhibits even higher abnormal revenue growth rates relative to either prior periods or other companies in the 1998-2001 period. The large relative increases and decreases in the market capitalization of U.S. capital markets in 1998-2001 may well have more grounding in risk-reward asset pricing theory than many commentators have recognized.capital markets; stock prices; Internet stocks; stock market bubble;

Making a difference - the appropriate use of web technology

Much has been written elsewhere about how, different Information Technology tools, can in principle be used by groups or communities to make their web sites more effective for Continued Professional Development. In practice, complex use is not often the case. In particular, three sites were studied in Scotland, which provided web facilities for the over 60s. The sites, and the communities they served, used only simple Information Technology. Nevertheless, they enabled their communities to participate effectively, on the 'right side', of the European population's 'digital divide'

Globalisation and Skills for Development in Rwanda and Tanzania

International Development,

A modelled global distribution of the kelp biome

Author's accepted version (postprint).This is an Accepted Manuscript of an article published by Elsevier in Biological Conservation on 17/11/2020.Available online: https://www.sciencedirect.com/science/article/pii/S0006320720308739?via%3DihubacceptedVersio

Increased dosage of the imprinted Ascl2 gene restrains two key endocrine lineages of the mouse Placenta

AbstractImprinted genes are expressed primarily from one parental allele by virtue of a germ line epigenetic process. Achaete-scute complex homolog 2 (Ascl2 aka Mash2) is a maternally expressed imprinted gene that plays a key role in placental and intestinal development. Loss-of-function of Ascl2 results in an expansion of the parietal trophoblast giant cell (P-TGC) lineage, an almost complete loss of Trophoblast specific protein alpha (Tpbpa) positive cells in the ectoplacental cone and embryonic failure by E10.5. Tpbpa expression marks the progenitors of some P-TGCs, two additional trophoblast giant cell lineages (spiral artery and canal), the spongiotrophoblast and the glycogen cell lineage. Using a transgenic model, here we show that elevated expression of Ascl2 reduced the number of P-TGC cells by 40%. Elevated Ascl2 also resulted in a marked loss of the spongiotrophoblast and a substantial mislocalisation of glycogen cells into the labyrinth. In addition, Ascl2-Tg placenta contained considerably more placental glycogen than wild type. Glycogen cells are normally located within the junctional zone in close contact with spongiotrophoblast cells, before migrating through the P-TGC layer into the maternal decidua late in gestation where their stores of glycogen are released. The failure of glycogen cells to release their stores of glycogen may explain both the inappropriate accumulation of glycogen and fetal growth restriction observed late in gestation in this model. In addition, using in a genetic cross we provide evidence that Ascl2 requires the activity of a second maternally expressed imprinted gene, Pleckstrin homology-like domain, family a, member 2 (Phlda2) to limit the expansion of the spongiotrophoblast. This “belts and braces” approach demonstrates the importance of genomic imprinting in regulating the size of the placental endocrine compartment for optimal placental development and fetal growth

Polarisation measurements with a CdTe pixel array detector for Laue hard X-ray focusing telescopes

Polarimetry is an area of high energy astrophysics which is still relatively unexplored, even though it is recognized that this type of measurement could drastically increase our knowledge of the physics and geometry of high energy sources. For this reason, in the context of the design of a Gamma-Ray Imager based on new hard-X and soft gamma ray focusing optics for the next ESA Cosmic Vision call for proposals (Cosmic Vision 2015-2025), it is important that this capability should be implemented in the principal on-board instrumentation. For the particular case of wide band-pass Laue optics we propose a focal plane based on a thick pixelated CdTe detector operating with high efficiency between 60-600 keV. The high segmentation of this type of detector (1-2 mm pixel size) and the good energy resolution (a few keV FWHM at 500 keV) will allow high sensitivity polarisation measurements (a few % for a 10 mCrab source in 106s) to be performed. We have evaluated the modulation Q factors and minimum detectable polarisation through the use of Monte Carlo simulations (based on the GEANT 4 toolkit) for on and off-axis sources with power law emission spectra using the point spread function of a Laue lens in a feasible configuration.Comment: 10 pages, 6 pages. Accepted for publication in Experimental Astronom

Broadening of band-gap in photonic crystals with optically saturated media

Due to strong absorption of the incident light, the media with high refractive index are considered restrictive for applications in photonic crystals (PhCs). The possibility to resolve this problem by optical saturation effectively minimizing the absorption of the PhC medium is discussed. Such approach might be promising for the significant broadening of the photonic band-gap.Comment: 10 page

Risk factors for excessive gestational weight gain in a UK population: A biopsychosocial model approach

Background Gestational weight gain (GWG) can have implications for the health of both mother and child. However, the contributing factors remain unclear. Despite the advantages of using a biopsychosocial approach, this approach has not been applied to study GWG in the UK. This study aimed to investigate the risk factors of excessive GWG in a UK population, employing a biopsychosocial model. Methods This study utilised data from the longitudinal Grown in Wales (GiW) cohort, which recruited women in late pregnancy in South Wales. Specifically, data was collected from midwife recorded notes and an extensive questionnaire completed prior to an elective caesarean section (ELCS) delivery. GWG was categorised according to Institute of Medicine (IOM) guidelines. The analysis was undertaken for 275 participants. Results In this population 56.0% of women had excessive GWG. Increased prenatal depression symptoms (Exp(B)=1.10, p=.019) and an overweight (Exp(B)=4.16, p<.001) or obese (Exp(B)=4.20, p=.010) pre-pregnancy BMI, consuming alcohol in pregnancy (Exp(B)=.37, p=.005) and an income of less than £18,000 (Exp(B)=.24, p=.043) and £25–43,000 (Exp(B)=.25, p=.002) were associated with excessive GWG. Conclusion GWG is complex and influenced by a range of biopsychosocial factors, with the high prevalence of excessive weight gain in this population a cause for concern. Women in the UK may benefit from a revised approach toward GWG within the National Health Service (NHS), such as tracking weight gain throughout pregnancy. Additionally, this research provides evidence for potential targets for future interventions, and potentially at-risk populations to target, to improve GWG outcomes