1,792 research outputs found
Data Points and Duration for Estimating Fuel Consumption of a Diesel Engine
Accurate measurement of fuel consumption is required to quantify the efficiency of an engine or predict emissions. As part of a larger project, accurate instantaneous fuel consumption data was required for a John Deere 4045T diesel engine. While establishing test criteria, it became evident that literature did not provide clear recommendations on the number of data points or time duration for data collection, for a diesel engine. Fuel consumption tests were conducted using up to 15 data points of percent fuel rate and up to 15 min of data collection. Based on statistical analysis of test results, at least 2 data points (0% and 100% of fuel rate) and 2 min of data collection are recommended for similar fuel-injected, diesel engine fuel rate tests. When a nonfuel injected engine is used, the Hogan et al. (2007) recommendation of at least 3 data points and 3.5 min of data collection should be followed
Data Points and Duration for Estimating Fuel Consumption of a Diesel Engine
Accurate measurement of fuel consumption is required to quantify the efficiency of an engine orpredict emissions. As part of a larger project, accurate instantaneous fuel consumption data was required for a John Deere 4045T diesel engine. While establishing test criteria, it became evident that literature did not provide clear recommendations on the number of data points or time duration for data collection, for a diesel engine. Fuel consumption tests were conducted using up to 15 data points of percent fuel rate and up to 15 min of data collection. ased on statistical analysis of test results, at least 2 data points (0% and 100% of fuel rate) and 2 min of data collection are recommended for similar fuel-injected, diesel engine fuel rate tests. When a nonfuel injected engine is used, the Hogan et al. (2007) recommendation of at least 3 data points and 3.5 min of data collection should be followed
Sedimentary inputs to the Nankai subduction zone: The importance of dispersed ash
We examine the importance of dispersed volcanic ash as a critical component of the aluminosilicate sediment entering the Nankai Trough, located south of Japanâs island of Honshu, via the subducting Philippine Sea plate. Multivariate statistical analyses of an extensive major, trace, and rare earth element data set from bulk sediment and discrete ash layers at Integrated Ocean Drilling Program (IODP) Sites C0011 and C0012 quantitatively determine the abundance and accumulation of multiple aluminosilicate inputs to the Nankai subduction zone. We identify the eolian input of continental material to both sites, and we further find that there are an additional three ash sources from Kyushu and Honshu, Japan and other regions. Some of these ash sources may themselves represent mixtures of ash inputs, although the final compositions appear statistically distinct. The dispersed ash comprises 38 ± 7 weight percent (wt%) of the bulk sediment at Site C0011, and 34 ± 4 wt% at Site C0012. When considering the entire sediment thickness at Site C0011, the dispersed ash component supplies 38000 ± 7000 g/cm2 of material to the Nankai subduction system, whereas Site C0012 supplies 20000 ± 3000 g/cm2. These values are enormous compared to the ~2500 g/cm2 (C0011) and ~1200 g/cm2 (C0012) of ash in the discrete ash layers. Therefore, the mass of volcanic ash and chemically equivalent alteration products (e.g., smectite) that are dispersed throughout the stratigraphic succession of bulk sediment appears to be up to 15â17 times greater than the mass of discrete ash layers. The composition of the dispersed ash component at Site C0011 appears linked to that of the discrete layers, and the mass accumulation rate for dispersed ash correlates best with discrete ash layer thickness. In contrast, at Site C0012 the mass accumulation rate for dispersed ash correlates better with the number of ash layers. Together, the discrete ash layers, dispersed ash, and clay-mineral assemblages present a complete record of volcanism and erosion of volcanic sources; and indicate that mass balances and subduction factory budgets should include the mass of dispersed ash for a more accurate assessment of volcanic contributions to large-scale geochemical cycling
Microsatellite Instability and its Significance to Hereditary and Sporadic Cancer
Up to one million people within the United States may have Lynch syndrome (LS), but only 10% have been diagnosed. Early identification of these individuals is critical because they are predisposed to the development of colorectal and several other cancers at a relatively young age. Individuals with LS carry a germline mutation in one of four DNA mismatch repair genes, which leads to hypermutability in simple repetitive DNA sequences. This hallmark molecular phenotype called microsatellite instability (MSI) is now widely used to screen individuals needing germline sequencing to confirm diagnosis of LS. Standardized markers for MSI testing and other improvements in methodology have greatly improved the accuracy and cost-effectiveness of MSI testing. The current trend toward universal MSI screening of all colorectal and endometrial cancers will save lives by identifying LS prior to the development of deadly cancer. New technologies for MSI detection, such as next generation sequencing, open the possibility of a single test for LS that determines both tumor MSI status and germline mutations. Moreover, MSI detection is poised to take on an even greater role in prediction of responses to the new immunotherapies targeted at MSI-positive tumors
Geochemical approaches to the quantification of dispersed volcanic ash in marine sediment
Volcanic ash has long been recognized in marine sediment, and given the prevalence of oceanic and continental arc
volcanism around the globe in regard to widespread transport of ash, its presence is nearly ubiquitous. However, the
presence/absence of very fine-grained ash material, and identification of its composition in particular, is challenging
given its broad classification as an âaluminosilicateâ component in sediment. Given this challenge, many studies of ash
have focused on discrete layers (that is, layers of ash that are of millimeter-to-centimeter or greater thickness, and their
respective glass shards) found in sequences at a variety of locations and timescales and how to link their presence with
a number of Earth processes. The ash that has been mixed into the bulk sediment, known as dispersed ash, has been
relatively unstudied, yet represents a large fraction of the total ash in a given sequence. The application of a combined
geochemical and statistical technique has allowed identification of this dispersed ash as part of the original ash
contribution to the sediment. In this paper, we summarize the development of these geochemical/statistical
techniques and provide case studies from the quantification of dispersed ash in the Caribbean Sea, equatorial Pacific
Ocean, and northwest Pacific Ocean. These geochemical studies (and their sedimentological precursors of smear slides)
collectively demonstrate that local and regional arc-related ash can be an important component of sedimentary
sequences throughout large regions of the ocean
Deep Learning from Dual-Energy Information for Whole-Heart Segmentation in Dual-Energy and Single-Energy Non-Contrast-Enhanced Cardiac CT
Deep learning-based whole-heart segmentation in coronary CT angiography
(CCTA) allows the extraction of quantitative imaging measures for
cardiovascular risk prediction. Automatic extraction of these measures in
patients undergoing only non-contrast-enhanced CT (NCCT) scanning would be
valuable. In this work, we leverage information provided by a dual-layer
detector CT scanner to obtain a reference standard in virtual non-contrast
(VNC) CT images mimicking NCCT images, and train a 3D convolutional neural
network (CNN) for the segmentation of VNC as well as NCCT images.
Contrast-enhanced acquisitions on a dual-layer detector CT scanner were
reconstructed into a CCTA and a perfectly aligned VNC image. In each CCTA
image, manual reference segmentations of the left ventricular (LV) myocardium,
LV cavity, right ventricle, left atrium, right atrium, ascending aorta, and
pulmonary artery trunk were obtained and propagated to the corresponding VNC
image. These VNC images and reference segmentations were used to train 3D CNNs
for automatic segmentation in either VNC images or NCCT images. Automatic
segmentations in VNC images showed good agreement with reference segmentations,
with an average Dice similarity coefficient of 0.897 \pm 0.034 and an average
symmetric surface distance of 1.42 \pm 0.45 mm. Volume differences [95%
confidence interval] between automatic NCCT and reference CCTA segmentations
were -19 [-67; 30] mL for LV myocardium, -25 [-78; 29] mL for LV cavity, -29
[-73; 14] mL for right ventricle, -20 [-62; 21] mL for left atrium, and -19
[-73; 34] mL for right atrium, respectively. In 214 (74%) NCCT images from an
independent multi-vendor multi-center set, two observers agreed that the
automatic segmentation was mostly accurate or better. This method might enable
quantification of additional cardiac measures from NCCT images for improved
cardiovascular risk prediction
Effect of Cell Age and Membrane Rigidity on Red Blood Cell Shape in Capillary Flow
Blood flow in the microcirculatory system is crucially affected by intrinsic red blood cell
(RBC) properties, such as their deformability. In the smallest vessels of this network, RBCs adapt
their shapes to the flow conditions. Although it is known that the age of RBCs modifies their physical
properties, such as increased cytosol viscosity and altered viscoelastic membrane properties, the
evolution of their shape-adapting abilities during senescence remains unclear. In this study, we
investigated the effect of RBC properties on the microcapillary in vitro flow behavior and their
characteristic shapes in microfluidic channels. For this, we fractioned RBCs from healthy donors
according to their age. Moreover, the membranes of fresh RBCs were chemically rigidified using
diamide to study the effect of isolated graded-membrane rigidity. Our results show that a fraction
of stable, asymmetric, off-centered slipper-like cells at high velocities decreases with increasing age
or diamide concentration. However, while old cells form an enhanced number of stable symmetric
croissants at the channel centerline, this shape class is suppressed for purely rigidified cells with
diamide. Our study provides further knowledge about the distinct effects of age-related changes of
intrinsic cell properties on the single-cell flow behavior of RBCs in confined flows due to inter-cellular
age-related cell heterogeneity
Superior antigen cross-presentation and XCR1 expression define human CD11c+CD141+ cells as homologues of mouse CD8+ dendritic cells
In recent years, human dendritic cells (DCs) could be subdivided into CD304+ plasmacytoid DCs (pDCs) and conventional DCs (cDCs), the latter encompassing the CD1c+, CD16+, and CD141+ DC subsets. To date, the low frequency of these DCs in human blood has essentially prevented functional studies defining their specific contribution to antigen presentation. We have established a protocol for an effective isolation of pDC and cDC subsets to high purity. Using this approach, we show that CD141+ DCs are the only cells in human blood that express the chemokine receptor XCR1 and respond to the specific ligand XCL1 by Ca2+ mobilization and potent chemotaxis. More importantly, we demonstrate that CD141+ DCs excel in cross-presentation of soluble or cell-associated antigen to CD8+ T cells when directly compared with CD1c+ DCs, CD16+ DCs, and pDCs from the same donors. Both in their functional XCR1 expression and their effective processing and presentation of exogenous antigen in the context of major histocompatibility complex class I, human CD141+ DCs correspond to mouse CD8+ DCs, a subset known for superior antigen cross-presentation in vivo. These data define CD141+ DCs as professional antigen cross-presenting DCs in the human
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