1,863 research outputs found
Computer analysis of longitudinal strength of ships
The purpose of the work was to produce a programme to calculate as accurately as possible the distributions of weight and buoyancy of a vessel, leading to the determination of sheer force and bending moment at each of 101 equally spaced ordinates overall. Calculations may be performed for still water or sine wave conditions. The programme, which provides tabular and/or graphical output, is written in Elliott Autocode and is in the Applications Group library of Elliott Automation Limited. It is extensively labelled and is flow charted throughout, the symbols used being those of the British Standards Institution, and illustrated in the glossary. A fairly detailed look into the âend lengthsâ suggested by Lloydâs (their Rpt. SR 64/15) has been undertaken in connection with the distribution of the continuous material. Ordinate tilting has been used, in the main, as opposed to âbase swingingâ techniques, the reasons being fully explained in the text. The programme was approved by Lloydâs Register of Shipping in August 1966, (except for those parts relating to (i) the coffin method for the continuous material and (ii) the application in a sine wave - which parts Lloyd's did hot check). It has also been further successfully tested by them in November, 1966. Comparisons with programmes written by Vickers Armstrongâs Limited, Barrow in Furness, B.S.R.A., Walls end, and the Naval Architecture Department of Glasgow University, on the same topic are included as an Appendix. Graphical results obtained by Lloyd's, B.S.R.A's and by this programme for one locally built vessel are included, for purposes of comparison. Results illustrated in the thesis are in both tabular and graphical form throughout
The Y-Band at 1.035 um: Photometric Calibration and the Dwarf Stellar/Sub-Stellar Color Sequence
We define and characterize a photometric bandpass (called "Y") that is
centered at 1.035 um, in between the traditionally classified ``optical'' and
``infrared'' spectral regimes. We present Y magnitudes and Y-H and Y-K colors
for a sample consisting mostly of photometric and spectral standards, spanning
the spectral type range sdO to T5V. Deep molecular absorption features in the
near-infrared spectra of extremely cool objects are such that the Y-H and Y-K
colors grow rapidly with advancing spectral type especially from late M through
mid L, substantially more rapidly than J-H or H-K which span a smaller total
dynamic range. Consistent with other near-infrared colors, however, Y-H and Y-K
colors turn blueward in the L6-L8 temperature range with later T-type objects
having colors similar to those of warmer M and L stars. Use of the Y-band
filter is nonetheless promising for easy identification of low-mass stars and
brown dwarfs, especially at young ages. The slope of the interstellar reddening
vector within this filter is A_Y = 0.38 x A_V. Reddening moves stars nearly
along the YHK dwarf color sequence making it more difficult to distinguish
unambiguously very low mass candidate brown dwarf objects from higher mass
stars seen, e.g. through the galactic plane or towards star-forming regions.
Other diagrams involving the Y-band may be somewhat more discriminating.Comment: accepted at PAS
Comparison of the RNA-amplification based methods RTâPCR and NASBA for the detection of circulating tumour cells
Increasingly, reverse transcriptase polymerase chain reaction (RTâPCR) is used to detect clinically significant tumour cells in blood or bone marrow. This may result in a redefinition of disease-free and clinical relapse. However, its clinical utility may be limited by lack of automation or reproducibility. Recent studies have suggested nucleic acid sequence-based amplification of target RNA may be more robust. In this study, nucleic acid sequence-based amplification was established to detect melanoma, colorectal and prostate cancer cells. Nucleic acid sequence-based amplification and RTâPCR both successfully amplified target RNA in peripheral blood samples from patients with melanoma and colorectal cancer, but only RTâPCR detected PSA in blood samples from patients with prostate cancer. There was relatively good agreement between sample replicates analyzed by RTâPCR (Kappa values of one for tyrosinase, 0.67 for CK-20 and one for PSA), but less agreement when analyzed by nucleic acid sequence-based amplification. This may limit the routine use of NASBA for the detection of clinically significant disease. In summary, RTâPCR appears at present to be the most reliable and reproducible method for the detection of low-level disease in cancer patients, although prospective studies are warranted to assess the clinical utility of different molecular diagnostic methods
Study protocol: The Adherence and Intensification of Medications (AIM) study - a cluster randomized controlled effectiveness study
Abstract Background Many patients with diabetes have poor blood pressure (BP) control. Pharmacological therapy is the cornerstone of effective BP treatment, yet there are high rates both of poor medication adherence and failure to intensify medications. Successful medication management requires an effective partnership between providers who initiate and increase doses of effective medications and patients who adhere to the regimen. Methods In this cluster-randomized controlled effectiveness study, primary care teams within sites were randomized to a program led by a clinical pharmacist trained in motivational interviewing-based behavioral counseling approaches and authorized to make BP medication changes or to usual care. This study involved the collection of data during a 14-month intervention period in three Department of Veterans Affairs facilities and two Kaiser Permanente Northern California facilities. The clinical pharmacist was supported by clinical information systems that enabled proactive identification of, and outreach to, eligible patients identified on the basis of poor BP control and either medication refill gaps or lack of recent medication intensification. The primary outcome is the relative change in systolic blood pressure (SBP) measurements over time. Secondary outcomes are changes in Hemoglobin A1c, low-density lipoprotein cholesterol (LDL), medication adherence determined from pharmacy refill data, and medication intensification rates. Discussion Integration of the three intervention elements - proactive identification, adherence counseling and medication intensification - is essential to achieve optimal levels of control for high-risk patients. Testing the effectiveness of this intervention at the team level allows us to study the program as it would typically be implemented within a clinic setting, including how it integrates with other elements of care. Trial Registration The ClinicalTrials.gov registration number is NCT00495794.http://deepblue.lib.umich.edu/bitstream/2027.42/78258/1/1745-6215-11-95.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78258/2/1745-6215-11-95.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/78258/3/1745-6215-11-95-S1.DOCPeer Reviewe
A revised age, structural model and origin for the North Pennine Orefield in the Alston Block, northern England: intrusion (Whin Sill)-related base metal (CuâPbâZnâF) mineralization
Mineralization and associated fluid migration events in the c. 1500â
km2 North Pennine Orefield (NPO) are known to be associated with tectonic activity, but the age of these tectonic events and origins of the base metal sulfide mineralization remain unresolved. New fieldwork in the Alston Block shows that mineralization post-dates a weakly developed phase of northâsouth shortening consistent with far-field Variscan basin inversion during the late Carboniferous. New observations of field relationships, coupled with microstructural observations and stress inversion analyses, together with ReâOs sulfide geochronology show that the vein-hosted mineralization (apart from barium minerals) was synchronous with a phase of northâsouth extension and eastâwest shortening coeval with emplacement of the Whin Sill (c. 297â294â
Ma). Thus the development of the NPO was related to an early Permian regional phase of transtensional deformation, mantle-sourced hydrothermal mineralization and magmatism in northern Britain. Previously proposed Mississippi Valley Type models, or alternatives relating mineralization to the influx of Mesozoic brines, can no longer be applied to the development of the NPO in the Alston Block. Our findings also mean that existing models for equivalent base metal sulfide fields worldwide (e.g. ZnâPb districts of Silesia, Poland and Tennessee, USA) may need to be reassessed
Comparison of data on Mutation Frequencies of Mice Caused by Radiation - Low Dose Model -
We propose LD(Low Dose) model, the extension of LDM model which was proposed
in the previous paper [Y. Manabe et al.: J. Phys. Soc. Jpn. 81 (2012) 104004]
to estimate biological damage caused by irradiation. LD model takes account of
all the considerable effects including cell death effect as well as
proliferation, apoptosis, repair. As a typical example of estimation, we apply
LD model to the experiment of mutation frequency on the responses induced by
the exposure to low levels of ionizing radiation. The most famous and extensive
experiments are those summarized by Russell and Kelly [Russell, W. L. & Kelly,
E. M: Proc. Natl Acad. Sci. USA 79 (1982) 539-541], which are known as
'Mega-mouse project'. This provides us with important information of the
frequencies of transmitted specific-locus mutations induced in mouse
spermatogonia stem-cells. It is found that the numerical results of the
mutation frequency of mice are in reasonable agreement with the experimental
data: the LD model reproduces the total dose and dose rate dependence of data
reasonably. In order to see such dose-rate dependence more explicitly, we
introduce the dose-rate effectiveness factor (DREF). This represents a sort of
preventable effects such as repair, apoptosis and death of broken cells, which
are to be competitive with proliferation effect of broken cells induced by
irradiation.Comment: subimitting to J. Phys. Soc. Jpn, 32 pages, 8 figure
Detection of epithelial cancer cells in peripheral blood by reverse transcriptase-polymerase chain reaction.
Circulating cancer cells in the blood play a central role in the metastatic process. Their number can be very small and techniques for their detection need to be both sensitive and specific. Polymerase chain reaction (PCR) has been successfully used to detect small numbers of tumour cells in haematological cancer in which abnormalities in DNA are sufficiently consistent to make this possible. For most solid tumours this not yet feasible. However, we have found that reverse transcriptase (RT)-PRC for tissue-specific gene expression is a useful technique for identifying small numbers of circulating cells in melanoma and neuroblastoma patients. In this report we describe detection of colon carcinoma cells by RT-PCR using CK 20 mRNA as a marker. Unlike other cytokeratin genes examined (CK 8 and CK 19), CK 20 was not transcribed in normal haematopoietic cells. This suggests a role for RT-PCR in the detection of colon carcinoma metastasis in blood and bone marrow, using CK 20 as the target gene. Future analysis of clinical material will determine the clinical significance of this technique
Assessment of the Risks of Mixtures of Major Use Veterinary Antibiotics in European Surface Waters
Effects of single veterinary antibiotics on a range of aquatic organisms have been explored in many studies. In reality, surface waters will be exposed to mixtures of these substances. In this study, we present an approach for establishing risks of antibiotic mixtures to surface waters and illustrate this by assessing risks of mixtures of three major use antibiotics (trimethoprim, tylosin, and lincomycin) to algal and cyanobacterial species in European surface waters. Ecotoxicity tests were initially performed to assess the combined effects of the antibiotics to the cyanobacteria Anabaena flos-aquae. The results were used to evaluate two mixture prediction models: concentration addition (CA) and independent action (IA). The CA model performed best at predicting the toxicity of the mixture with the experimental 96 h EC50 for the antibiotic mixture being 0.248 ÎŒmol/L compared to the CA predicted EC50 of 0.21 ÎŒmol/L. The CA model was therefore used alongside predictions of exposure for different European scenarios and estimations of hazards obtained from species sensitivity distributions to estimate risks of mixtures of the three antibiotics. Risk quotients for the different scenarios ranged from 0.066 to 385 indicating that the combination of three substances could be causing adverse impacts on algal communities in European surface waters. This could have important implications for primary production and nutrient cycling. Tylosin contributed most to the risk followed by lincomycin and trimethoprim. While we have explored only three antibiotics, the combined experimental and modeling approach could readily be applied to the wider range of antibiotics that are in use
Osmium uptake, distribution, and 187Os/188Os and 187Re/188Os compositions in Phaeophyceae macroalgae, Fucus vesiculosus: Implications for determining the 187Os/188Os composition of seawater
The osmium isotopic composition (187Os/188Os) of seawater reflects the balance of input from mantle-, continental- and anthropogenic-derived sources. This study utilizes the Phaeophyceae, Fucus vesiculosus, to analyse its Os abundance and uptake, as well as to assess if macroalgae records the Os isotope composition of the seawater in which it lives. The data demonstrates that Os is not located in one specific biological structure within macroalgae, but is found throughout the organism. Osmium uptake was measured by culturing F. vesiculosus non-fertile tips with different concentrations of Os with a known 187Os/188Os composition (âŒ0.16), which is significantly different from the background isotopic composition of local seawater (âŒ0.94). The Os abundance of cultured non-fertile tips show a positive correlation to the concentration of the Os doped seawater. Moreover, the 187Os/188Os composition of the seaweed equaled that of the culture medium, stongly confirming the possible use of macroalgae as a biological proxy for the Os isotopic composition of the seawater
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