Soot and black carbon (BC) particles are generated in the
incomplete combustion of fossil fuels, biomass, and biofuels. These airborne
particles affect air quality, human health, aerosol–cloud ...interactions,
precipitation formation, and climate. At present, the climate effects of BC
particles are not well understood. Their role in cloud formation is obscured
by their chemical and physical variability and by the internal mixing
states of these particles with other compounds. Ice nucleation in field
studies is often difficult to interpret. Nonetheless, most field studies
seem to suggest that BC particles are not efficient ice-nucleating particles
(INPs). On the other hand, laboratory measurements show that in some cases,
BC particles can be highly active INPs under certain conditions. By working
with well-characterized BC particles, our aim is to systematically establish
the factors that govern the ice nucleation activity of BC. The current study
focuses on laboratory measurements of the effectiveness of BC-containing
aerosol in the formation of ice crystals in temperature and ice
supersaturation conditions relevant to cirrus clouds. We examine ice nucleation on BC particles under water-subsaturated cirrus
cloud conditions, commonly understood as deposition-mode ice nucleation.
We study a series of well-characterized commercial carbon black particles
with varying morphologies and surface chemistries as well as ethylene
flame-generated combustion soot. The carbon black particles used in this
study are proxies for atmospherically relevant BC aerosols. These samples
were characterized by electron microscopy, mass spectrometry, and optical
scattering measurements. Ice nucleation activity was systematically examined
in temperature and saturation conditions in the ranges of 217≤T≤235 K and 1.0≤Sice≤1.5 and 0.59≤Swater≤0.98, respectively, using a SPectrometer for Ice Nuclei (SPIN) instrument,
which is a continuous-flow diffusion chamber coupled with instrumentation to
measure light scattering and polarization. To study the effect of coatings
on INPs, the BC-containing particles were coated with organic acids found in
the atmosphere, namely stearic acid, cis-pinonic acid, and oxalic acid. The results show significant variations in ice nucleation activity as a
function of size, morphology, and surface chemistry of the BC particles. The
measured ice nucleation activity dependencies on temperature,
supersaturation conditions, and the physicochemical properties of the BC
particles are consistent with an ice nucleation mechanism of pore
condensation followed by freezing. Coatings and surface oxidation modify the
initial formation efficiency of pristine ice crystals on BC-containing
aerosol. Depending on the BC material and the coating, both inhibition and
enhancement in INP activity were observed. Our measurements at low
temperatures complement published data and highlight the capability of some
BC particles to nucleate ice under low ice supersaturation conditions. These
results are expected to help refine theories relating to soot INP activation
in the atmosphere.
A
bstract
The
p
T
-differential production cross sections of prompt and non-prompt (produced in beauty-hadron decays) D mesons were measured by the ALICE experiment at midrapidity (
|
y
|
<
0
.
5) in ...proton-proton collisions at
s
= 5
.
02 TeV. The data sample used in the analysis corresponds to an integrated luminosity of (19
.
3
±
0
.
4) nb
−
1
. D mesons were reconstructed from their decays D
0
→
K
−
π
+
, D
+
→
K
−
π
+
π
+
, and
D
s
+
→
ϕ
π
+
→
K
−
K
+
π
+
and their charge conjugates. Compared to previous measurements in the same rapidity region, the cross sections of prompt D
+
and
D
s
+
mesons have an extended
p
T
coverage and total uncertainties reduced by a factor ranging from 1.05 to 1.6, depending on
p
T
, allowing for a more precise determination of their
p
T
-integrated cross sections. The results are well described by perturbative QCD calculations. The fragmentation fraction of heavy quarks to strange mesons divided by the one to non-strange mesons,
f
s
/
(
f
u
+
f
d
), is compatible for charm and beauty quarks and with previous measurements at different centre-of-mass energies and collision systems. The
b
b
¯
production cross section per rapidity unit at midrapidity, estimated from non-prompt D-meson measurements, is
d
σ
b
b
¯
/
d
y
y
<
0.5
=
34.5
±
2.4
stat
−
2.9
+
4.7
tot
.
syst
μb. It is compatible with previous measurements at the same centre-of-mass energy and with the cross section pre- dicted by perturbative QCD calculations.
This paper presents the measurements of
π
±
,
K
±
,
p
and
p
¯
transverse momentum (
p
T
) spectra as a function of charged-particle multiplicity density in proton–proton (pp) collisions at
s
=
13
TeV
...with the ALICE detector at the LHC. Such study allows us to isolate the center-of-mass energy dependence of light-flavour particle production. The measurements reported here cover a
p
T
range from 0.1 to 20
GeV
/
c
and are done in the rapidity interval
|
y
|
<
0.5
. The
p
T
-differential particle ratios exhibit an evolution with multiplicity, similar to that observed in pp collisions at
s
=
7
TeV
, which is qualitatively described by some of the hydrodynamical and pQCD-inspired models discussed in this paper. Furthermore, the
p
T
-integrated hadron-to-pion yield ratios measured in pp collisions at two different center-of-mass energies are consistent when compared at similar multiplicities. This also extends to strange and multi-strange hadrons, suggesting that, at LHC energies, particle hadrochemistry scales with particle multiplicity the same way under different collision energies and colliding systems.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
SOCS‐1 was originally identified as an inhibitor of interleukin‐6 signal transduction and is a member of a family of proteins (SOCS‐1 to SOCS‐7 and CIS) that contain an SH2 domain and a conserved ...carboxyl‐terminal SOCS box motif. Mutation studies have established that critical contributions from both the amino‐terminal and SH2 domains are essential for SOCS‐1 and SOCS‐3 to inhibit cytokine signaling. Inhibition of cytokine‐dependent activation of STAT3 occurred in cells expressing either SOCS‐1 or SOCS‐3, but unlike SOCS‐1, SOCS‐3 did not directly interact with or inhibit the activity of JAK kinases. Although the conserved SOCS box motif appeared to be dispensable for SOCS‐1 and SOCS‐3 action when over‐expressed, this domain interacts with elongin proteins and may be important in regulating protein turnover. In gene knockout studies, SOCS‐1−/− mice were born but failed to thrive and died within 3 weeks of age with fatty degeneration of the liver and hemopoietic infiltration of several organs. The thymus in SOCS‐1−/− mice was small, the animals were lymphopenic, and deficiencies in B lymphocytes were evident within hemopoietic organs. We propose that the absence of SOCS‐1 in these mice prevents lymphocytes and liver cells from appropriately controlling signals from cytokines with cytotoxic side effects. J. Leukoc. Biol. 66: 588–592; 1999.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
We report studies of ultrahigh-energy cosmic-ray composition via analysis of depth of air shower maximum (X(max)), for air shower events collected by the High-Resolution Fly's Eye (HiRes) ...observatory. The HiRes data are consistent with a constant elongation rate d<X(max)>/dlog(E) of 47.9+/-6.0(stat)+/-3.2(syst) g/cm2/decade for energies between 1.6 and 63 EeV, and are consistent with a predominantly protonic composition of cosmic rays when interpreted via the QGSJET01 and QGSJET-II high-energy hadronic interaction models. These measurements constrain models in which the galactic-to-extragalactic transition is the cause of the energy spectrum ankle at 4x10(18) eV.
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Available for:
CMK, CTK, FMFMET, IJS, NUK, PNG, UM
•Changes in tube potential in CT acquisition changes muscle attenuation values.•Changes in tube potential changes skeletal muscle index and steatotic muscle area.•CT acquisition parameters should be ...standardized for body segmentation.
Our purpose was to investigate whether tube potential in contrast-enhanced computed tomography (CT) affects body composition analysis.
Images from dual-source, dual-energy CT from the abdomen with intravenous contrast media administration were used. A total of 17 patients (11 women, mean age 52) with a mean body mass index of 20.8 kg/cm2 were included. Simultaneously acquired images with a tube voltage of 80 kV and 140 kV were compared. Body composition was analyzed on a single slice at the L3 level. Parameters evaluated included muscle and fat attenuation (Hounsfield units HU), skeletal muscle index (cm2/m2), muscle area (cm2), and steatotic muscle area (cm2). Significant differences between 80 kV and 140 kV series were compared using the paired Student's t test.
Tube potential affected muscle attenuation with an average difference of 17% between 80 kV and 140 kV series (48 HU versus 41 HU, P < 0.01), fat attenuation (−84 HU versus −69 HU, P < 0.01), skeletal muscle index of 5.2% (40.1 cm2/m2 versus 42.2 cm2/m2, P < 0.01), muscle area of 5.1% (117 cm2 versus 123 cm2, P < 0.01), and steatotic muscle area of 12.9% (31 cm2 versus 35 cm2, P < 0.01).
Tube potential significantly affects body segmentation in contrast-enhanced CT.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The in vitro study demonstrates wirelessly controlled modulation of neural activity using magnetoelectric nanoparticles (MENPs), synchronized to magnetic field application with a sub-25-msec temporal ...response. Herein, MENPs are sub-30-nm CoFe2O4@BaTiO3 core-shell nanostructures. MENPs were added to E18 rat hippocampal cell cultures (0.5 μg of MENPs per 100,000 neurons) tagged with fluorescent Ca2+ sensitive indicator cal520. MENPs were shown to wirelessly induce calcium transients which were synchronized with application of 1200-Oe bipolar 25-msec magnetic pulses at a rate of 20 pulses/sec. The observed calcium transients were similar, in shape and magnitude, to those generated through the control electric field stimulation with a 50-μA current, and they were inhibited by the sodium channel blocker tetrodotoxin. The observed MENP-based magnetic excitation of neural activity is in agreement with the non-linear M − H hysteresis loop of the MENPs, wherein the MENPs’ coercivity value sets the threshold for the externally applied magnetic field.
•A study through a reduced in vitro model (on E18 rat hippocampal cell cultures) for the first time demonstrates how 30-nm MENPs can be used to wirelessly induce neural activity via application of magnetic fields, with a sub-25-msec temporal response.•The property of the nanoparticles such as the magnetic coercivity is used as a wireless switch to activate action potential in selected regions.•The validity of MENPs-based neural firing approach is confirmed through different positive and negative control measurements.•The importance of having MENPs adequately dispersed to ensure the desired wireless neural firing control operation is being demonstrated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Summary Cholangiocarcinoma is a highly lethal cancer of the biliary tract. The intrahepatic subtype of cholangiocarcinoma is increasing in incidence globally. Despite technologic advancements over ...the past decade, little is known about the somatic changes that occur in these tumors. The goal of this study was to determine the frequency of common oncogenes in resected cholangiocarcinoma specimens that could provide potential therapeutic targets for patients diagnosed with cholangiocarcinoma. Formalin-fixed, paraffin-embedded tissue blocks from 94 resected cholangiocarcinomas were used to extract DNA from areas comprising more than 20% tumor. Specimens were evaluated using the Sequenom MassARRAY OncoCarta Mutation Profiler Panel (San Diego, CA). This matrix-assisted laser desorption/ionization–time of flight mass spectrometry single genotyping panel evaluates 19 oncogenes for 238 somatic mutations. Twenty-five mutations were identified in 23 of the 94 cholangiocarcinomas within the following oncogenes: KRAS (n = 12), PIK3CA (n = 5), MET (n = 4), EGFR (n = 1), BRAF (n = 2), and NRAS (n = 1). Mutations were identified in 7 (26%) of 27 extrahepatic cholangiocarcinomas and 16 (24%) of 67 intrahepatic cholangiocarcinomas. When combined with IDH1/2 testing, 40 (43%) of the 94 cholangiocarcinomas had a detectable mutation. MassARRAY technology can be used to detect mutations in a wide variety of oncogenes using paraffin-embedded tissue. Clinical testing for somatic mutations may drive personalized therapy selection for cholangiocarcinomas in the future. The variety of mutations detected suggests that a multiplexed mutation detection approach may be necessary for managing patients with biliary tract malignancy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
499.
PROSPECT-II physics opportunities Andriamirado, M; Balantekin, A B; Band, H R ...
Journal of physics. G, Nuclear and particle physics,
07/2022, Volume:
49, Issue:
7
Journal Article
Peer reviewed
Open access
Abstract
The precision reactor oscillation and spectrum experiment, PROSPECT, has made world-leading measurements of reactor antineutrinos at short baselines. In its first phase, conducted at the ...high flux isotope reactor (HFIR) at Oak Ridge National Laboratory, PROSPECT produced some of the strongest limits on eV-scale sterile neutrinos, made a precision measurement of the reactor antineutrino spectrum from
235
U, and demonstrated the observation of reactor antineutrinos in an aboveground detector with good energy resolution and well-controlled backgrounds. The PROSPECT collaboration is now preparing an upgraded detector, PROSPECT-II, to probe yet unexplored parameter space for sterile neutrinos and contribute to a full resolution of the reactor antineutrino anomaly, a longstanding puzzle in neutrino physics. By pressing forward on the world’s most precise measurement of the
235
U antineutrino spectrum and measuring the absolute flux of antineutrinos from
235
U, PROSPECT-II will sharpen a tool with potential value for basic neutrino science, nuclear data validation, and nuclear security applications. Following a two-year deployment at HFIR, an additional PROSPECT-II deployment at a low enriched uranium reactor could make complementary measurements of the neutrino yield from other fission isotopes. PROSPECT-II provides a unique opportunity to continue the study of reactor antineutrinos at short baselines, taking advantage of demonstrated elements of the original PROSPECT design and close access to a highly enriched uranium reactor core.
Stream processing is widely used for real-time data processing and decision-making, leading to tens of thousands of streaming jobs deployed in ByteDance cloud. Since those streaming jobs usually run ...for several days or longer and the input workloads vary over time, they usually face diverse runtime issues such as processing lag and varying failures. This requires runtime management to resolve such runtime issues automatically. However, designing a runtime management service on the ByteDance scale is challenging. In particular, the service has to concurrently manage cluster-wide streaming jobs in a scalable and extensible manner. Furthermore, it should also be able to manage diverse streaming jobs effectively.
To this end, we propose
StreamOps
to enable cloud-native runtime management for streaming jobs in ByteDance.
StreamOps
has three main designs to address the challenges. 1) To allow for scalability,
StreamOps
is running as a standalone lightweight control plane to manage cluster-wide streaming jobs. 2) To enable extensible runtime management,
StreamOps
abstracts control policies to identify and resolve runtime issues. New control policies can be implemented with a detect-diagnose-resolve programming paradigm. Each control policy is also configurable for different streaming jobs according to the performance requirements. 3) To mitigate processing lag and handling failures effectively,
StreamOps
features three control policies, i.e., auto-scaler, straggler detector, and job doctor, that are inspired by state-of-the-art research and production experiences at ByteDance. In this paper, we introduce the design decisions we made and the experiences we learned from building
StreamOps.
We evaluate
StreamOps
in our production environment, and the experiment results have further validated our system design.
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