1,913 research outputs found
An Examination of the Variables Affecting RFID Tag Readability in a Conveyer Belt Environment
There is a growing list of companies implementing radio frequency identification (RFID) systems to help optimize their supply chain processes. These companies realize that a successful RFID system can potentially lead to lower supply chain inventory levels, reduced operating expenses, and greater visibility throughout the supply chain. However, since RFID technology is still relatively immature, a majority of the applications experience less than perfect read rates for tagged items moving through the supply chain. This paper reports the results for a variety of different arrangements of variables that may influence the readability of the RFID tags in a conveyer belt environment. The variables tested for this study were tag placement on the package, tag orientation, conveyer belt speed, tag type, package contents, and the reader antenna distance from the conveyer belt. The goal of this research was to determine how these variables influenced the readability of the RFID tags. The results from this procedure determined that metal and water have a negative affect on the read accuracy of the RFID tags. The read accuracy also decreased as conveyer belt speed increased, and as a function of the distance between the antenna and the conveyer belt. Multiple linear regression was used to create \u27Hit Rate\u27 equations that can be used to predict the hit rate for the three types of products tested under various speeds and distances
SMASHing the LMC: A Tidally-induced Warp in the Outer LMC and a Large-scale Reddening Map
We present a study of the three-dimensional (3D) structure of the Large
Magellanic Cloud (LMC) using ~2.2 million red clump (RC) stars selected from
the Survey of the MAgellanic Stellar History. To correct for line-of-sight dust
extinction, the intrinsic RC color and magnitude and their radial dependence
are carefully measured by using internal nearly dust-free regions. These are
then used to construct an accurate 2D reddening map (165 square degrees with
~10 arcmin resolution) of the LMC disk and the 3D spatial distribution of RC
stars. An inclined disk model is fit to the 2D distance map yielding a best-fit
inclination angle i = 25.86(+0.73,-1.39) degrees with random errors of +\-0.19
degrees and line-of-nodes position angle theta = 149.23(+6.43,-8.35) degrees
with random errors of +/-0.49 degrees. These angles vary with galactic radius,
indicating that the LMC disk is warped and twisted likely due to the repeated
tidal interactions with the Small Magellanic Cloud (SMC). For the first time,
our data reveal a significant warp in the southwestern part of the outer disk
starting at rho ~ 7 degrees that departs from the defined LMC plane up to ~4
kpc toward the SMC, suggesting that it originated from a strong interaction
with the SMC. In addition, the inner disk encompassing the off-centered bar
appears to be tilted up to 5-15 degrees relative to the rest of the LMC disk.
These findings on the outer warp and the tilted bar are consistent with the
predictions from the Besla et al. simulation of a recent direct collision with
the SMC.Comment: 25 pages, 15 figures, published in Ap
Solar thermoelectricity Via Advanced Latent Heat Storage
An aspect of the present disclosure is a system that includes a thermal valve having a first position and a second position, a heat transfer fluid, and an energy converter where, when in the first position, the thermal valve prevents the transfer of heat from the heat transfer fluid to the energy converter, and when in the second position, the thermal valve allows the transfer of heat from the heat transfer fluid to the energy converter, such that at least a portion of the heat transferred is converted to electricity by the energy converter
Prevention of insulin resistance in adolescents at risk for type 2 diabetes with depressive symptoms: 1-year follow-up of a randomized trial
Background: Depression is associated with poor insulin sensitivity. We evaluated the long-term effects of a cognitive behavioral therapy (CBT) program for prevention of depression on insulin sensitivity in adolescents at risk for type 2 diabetes (T2D) with depressive symptoms.
Methods: One-hundred nineteen adolescent females with overweight/obesity,T2Dfamily history, and mild-to-moderate depressive symptoms were randomized to a 6-week CBT group (n = 61) or 6-week health education (HE) control group (n = 58). At baseline, posttreatment, and 1 year, depressive symptoms were assessed, and whole body insulin sensitivity (WBISI) was estimated from oral glucose tolerance tests.Dual energy X-ray absorptiometry assessed fat mass at baseline and 1 year. Primary outcomes were 1-year changes in depression and insulin sensitivity, adjusting for adiposity and other relevant covariates. Secondary outcomeswere fasting and 2-hr insulin and glucose.We also evaluated the moderating effect of baseline depressive symptom severity.
Results: Depressive symptoms decreased in both groups (P \u3c .001). Insulin sensitivity was stable inCBTandHE(ÎWBISI: .1 vs. .3) and did not differ between groups (P=.63).However, among girls with greater (moderate) baseline depressive symptoms (N = 78), those in CBT developed lower 2- hr insulin than those in HE (Î-16 vs. 16 ïżœIU/mL, P \u3c .05). Additional metabolic benefits of CBT were seen for this subgroup in post hoc analyses of posttreatment to 1-year change.
Conclusions: Adolescent females at risk for T2D decreased depressive symptoms and stabilized insulin sensitivity 1 year following brief CBT or HE. Further studies are required to determine if adolescents with moderate depression show metabolic benefits after CBT
New X-ray Clusters in the EMSS I: Modifications to the XLF
The complete ensemble of Einstein Imaging Proportional Counter (IPC) X-ray
images has been re-processed and re-analyzed using a multi-aperture source
detection algorithm. A catalog of 772 new source candidates detected within the
central regions of the 1435 IPC fields comprising the Extended Medium
Sensitivity Survey (EMSS) has been compiled. By comparison, 478 EMSS sources
fall within the same area of sky. A randomly-selected subsample of 133 fields
was first examined. We found that most of these sources are either the
summation of two or more lower count rate point sources that fall within the
larger detection apertures or are single point sources, while \leq 2.3% of the
full catalog of sources are extrapolated to be actual distant (z > 0.14)
clusters whose extended X-ray structure kept them from being detected in the
EMSS despite having sufficient total flux.
We then constructed other subsamples specifically selected to contain those
X-ray sources most likely to be clusters. Both a database search and an optical
imaging campaign have found several new distant clusters, setting a firm lower
limit on the number of new clusters in the entire catalog. We estimate that the
original EMSS cluster sample is 72-83% complete. We update the Henry et al.
1992 EMSS distant cluster sample with more recent information, and use the
redshifts and X-ray luminosities for these new EMSS clusters to compute a
revised X-ray Luminosity Function (XLF). The addition of these new high-z,
high-L_X clusters to the EMSS is sufficient to remove the requirement for
``negative'' evolution at high-L_X out to z~0.5. We conclude that the EMSS has
systematically missed clusters of low surface brightness.Comment: Accepted to ApJ, 32 pages, 8 figures, uses emulateapj5.sty, for
associated data table see
http://casa.colorado.edu/~lewisad/research/nemsscatalog.htm
The Generation R Study Biobank: a resource for epidemiological studies in children and their parents
The Generation R Study is a population-based prospective cohort study from fetal life until young adulthood. The study is designed to identify early environmental and genetic causes of normal and abnormal growth, development and health from fetal life until young adulthood. In total, 9,778 mothers were enrolled in the study. Prenatal and postnatal data collection is conducted by physical examinations, questionnaires, interviews, ultrasound examinations and biological samples. Major efforts have been conducted for collecting biological specimens including DNA, blood for phenotypes and urine samples. In this paper, the collection, processing and storage of these biological specimens are described. Together with detailed phenotype measurements, these biological specimens form a unique resource for epidemiological studies focused on environmental exposures, genetic determinants and their interactions in relation to growth, health and development from fetal life onwards
The Effective Temperature Scale of Galactic Red Supergiants: Cool, But Not As Cool As We Thought
We use moderate-resolution optical spectrophotometry and the new MARCS
stellar atmosphere models to determine the effective temperatures of 74
Galactic red supergiants. From these we find a new effective temperature scale
that is significantly warmer than those in the literature. We show that this
temperature scale, along with the newly derived bolometric corrections, gives
much better agreement between our red supergiants and stellar evolutionary
tracks. This agreement provides an independent verification of our new
temperature scale. The combination of effective temperature and bolometric
luminosities allows us to calculate stellar radii; the coolest and most
luminous stars have radii of roughly 1500 solar radii (7 AU), in excellent
accordance with the largest stellar radii predicted from current evolutionary
theory. We find that similar results are obtained for the effective
temperatures and bolometric luminosities using only the de-reddened V-K colors,
providing a powerful demonstration of the self-consistency of the MARCS models.Comment: 32 pages, 16 figures; Accepted by the Astrophysical Journa
Significance of lobular intraepithelial neoplasia at margins of breast conservation specimens: a report of 38 cases and literature review
<p>Abstract</p> <p>Background</p> <p>Presence of lobular intraepithelial neoplasia (LIN) is not routinely reported as part of margin assessment in breast conservation therapy (BCT) as in ductal carcinoma in situ (DCIS). With new emerging evidence of LIN as possible precursor lesion, the hypothesis is that LIN at the margin may increase the risk of local recurrence with BCT. The aim is to determine whether there is an increase incidence of recurrence when LIN is found at surgical margins on BCT.</p> <p>Methods</p> <p>We retrospectively reviewed a total of 1,334 BCT at a single institution in a 10 year period. Inclusion criteria are positive margin with LIN from primary BCT containing invasive and/or in situ carcinoma with comparison to the negative control group who had similar diseases with negative margin for LIN.</p> <p>Results</p> <p>We identified 38 cases (2.8%) with LIN either lobular carcinoma in situ/atypical lobular hyperplasia (LCIS/ALH) at a margin on initial BCT with 36% recurrence rate. Of the 38 cases: 5 (13%) were lost to follow-up, 12 (32%) had no further procedures performed and 21 (55%) had re-excision. Out of 21 patients who had re-excisions, 12 (57%) had residual invasive carcinoma or DCIS, three (14%) had pleomorphic LCIS and 4 (19%) showed residual classic type LCIS. 71% had significant residual disease (local recurrence) and 29% had no residual disease. A negative control group consisted of 38 cases. We found two patients with bone or brain metastasis and one local recurrence. Clinical follow up periods range from 1 to 109 months.</p> <p>Conclusions</p> <p>LIN found at a margin on BCT showed a significant recurrent ipsilateral disease. Our study supports the view that LIN seen at the margin may play a role in recurrence.</p
Multidecadal accumulation of anthropogenic and remineralized dissolved inorganic carbon along the Extended Ellett Line in the northeast Atlantic Ocean
Marine carbonate chemistry measurements have been carried out annually since 2009 during UK research cruises along the Extended Ellett Line (EEL), a hydrographic transect in the northeast Atlantic Ocean. The EEL intersects several water masses that are key to the global thermohaline circulation, and therefore the cruises sample a region in which it is critical to monitor secular physical and biogeochemical changes. We have combined results from these EEL cruises with existing quality-controlled observational data syntheses to produce a hydrographic time series for the EEL from 1981 to 2013. This reveals multidecadal increases in dissolved inorganic carbon (DIC) throughout the water column, with a near-surface maximum rate of 1.80â±â0.45â”molâkgâ1âyrâ1. Anthropogenic CO2 accumulation was assessed, using simultaneous changes in apparent oxygen utilization (AOU) and total alkalinity (TA) as proxies for the biogeochemical processes that influence DIC. The stable carbon isotope composition of DIC (ÎŽ13CDIC) was also determined and used as an independent test of our method. We calculated a volume-integrated anthropogenic CO2 accumulation rate of 2.8â±â0.4âmgâCâmâ3âyrâ1 along the EEL, which is about double the global mean. The anthropogenic CO2 component accounts for only 31â±â6% of the total DIC increase. The remainder is derived from increased organic matter remineralization, which we attribute to the lateral redistribution of water masses that accompanies subpolar gyre contraction. Output from a general circulation ecosystem model demonstrates that spatiotemporal heterogeneity in the observations has not significantly biased our multidecadal rate of change calculations and indicates that the EEL observations have been tracking distal changes in the surrounding North Atlantic and Nordic Seas
CANDELS: The progenitors of compact quiescent galaxies at z~2
We combine high-resolution HST/WFC3 images with multi-wavelength photometry
to track the evolution of structure and activity of massive (log(M*) > 10)
galaxies at redshifts z = 1.4 - 3 in two fields of the Cosmic Assembly
Near-infrared Deep Extragalactic Legacy Survey (CANDELS). We detect compact,
star-forming galaxies (cSFGs) whose number densities, masses, sizes, and star
formation rates qualify them as likely progenitors of compact, quiescent,
massive galaxies (cQGs) at z = 1.5 - 3. At z > 2 most cSFGs have specific
star-formation rates (sSFR = 10^-9 yr^-1) half that of typical, massive SFGs at
the same epoch, and host X-ray luminous AGN 30 times (~30%) more frequently.
These properties suggest that cSFGs are formed by gas-rich processes (mergers
or disk-instabilities) that induce a compact starburst and feed an AGN, which,
in turn, quench the star formation on dynamical timescales (few 10^8 yr). The
cSFGs are continuously being formed at z = 2 - 3 and fade to cQGs by z = 1.5.
After this epoch, cSFGs are rare, thereby truncating the formation of new cQGs.
Meanwhile, down to z = 1, existing cQGs continue to enlarge to match local QGs
in size, while less-gas-rich mergers and other secular mechanisms shepherd
(larger) SFGs as later arrivals to the red sequence. In summary, we propose two
evolutionary scenarios of QG formation: an early (z > 2), fast-formation path
of rapidly-quenched cSFGs that evolve into cQGs that later enlarge within the
quiescent phase, and a slow, late-arrival (z < 2) path for SFGs to form QGs
without passing through a compact state.Comment: Submitted to the Astrophysical Journal Letters, 6 pages, 4 figure
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