Accumulating evidence reveals that metabolic and cell survival pathways are closely related, sharing common signaling molecules. Hexokinase catalyzes the phosphorylation of glucose, the rate-limiting ...first step of glycolysis. Hexokinase II (HK-II) is a predominant isoform in insulin-sensitive tissues such as heart, skeletal muscle, and adipose tissues. It is also upregulated in many types of tumors associated with enhanced aerobic glycolysis in tumor cells, the Warburg effect. In addition to the fundamental role in glycolysis, HK-II is increasingly recognized as a component of a survival signaling nexus. This review summarizes recent advances in understanding the protective role of HK-II, controlling cellular growth, preventing mitochondrial death pathway and enhancing autophagy, with a particular focus on the interaction between HK-II and Akt/mTOR pathway to integrate metabolic status with the control of cell survival.
The Lagrangian that defines quantum chromodynamics (QCD), the strong interaction piece of the Standard Model, appears very simple. Nevertheless, it is responsible for an astonishing array of ...high-level phenomena with enormous apparent complexity, e.g., the existence, number and structure of atomic nuclei. The source of all these things can be traced to emergent mass, which might itself be QCD’s self-stabilising mechanism. A background to this perspective is provided, presenting, inter alia, a discussion of the gluon mass and QCD’s process-independent effective charge and highlighting an array of observable expressions of emergent mass, ranging from its manifestations in pion parton distributions to those in nucleon electromagnetic form factors.
Using a relativized diquark model Hamiltonian, we calculate the masses of
J
PC
=
0
+
+
ground-state tetraquarks in the following systems:
b
s
b
¯
s
¯
,
b
b
n
¯
n
¯
(
n
=
u
,
d
),
b
b
s
¯
s
¯
,
c
c
c
...¯
c
¯
,
b
b
b
¯
b
¯
,
b
c
b
¯
c
¯
and
b
b
c
¯
c
¯
. We also compute extensive spectra for the fully-heavy quark flavour combinations. Finally, as a test of the diquark model approach, we compute the masses of fully-heavy baryons in the diquark model. Our results may be compared soon to the forthcoming experimental data for fully-heavy three-quark systems.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
ABSTRACT
The Coma cluster is the nearest massive ($M \gtrsim 10^{15}\, \mathrm{M_\odot }$) galaxy cluster, making it an excellent laboratory to probe the influence of the cluster environment on ...galaxy star formation. Here, we present a sample of 41 galaxies with disturbed morphologies consistent with ram pressure stripping. These galaxies are identified visually using high-quality, multiband imaging from the Canada–France–Hawaii telescope covering ${\sim}9\, \mathrm{deg^2}$ of the Coma cluster. These ‘stripping candidates’ are clear outliers in common quantitative morphological measures, such as concentration-asymmetry and Gini-M20, confirming their disturbed nature. Based on the orientations of observed asymmetries, as well as the galaxy positions in projected phase space, these candidates are consistent with galaxies being stripped shortly after infall on to the Coma cluster. Finally, the stripping candidates show enhanced star formation rates, both relative to ‘normal’ star-forming Coma galaxies and isolated galaxies in the field. Ram pressure is likely driving an enhancement in star formation during the stripping phase, prior to quenching. On the whole, ram pressure stripping appears to be ubiquitous across all regions of the Coma cluster.
Kaon and pion parton distributions Cui, Z.-F.; Ding, M.; Gao, F. ...
The European physical journal. C, Particles and fields,
11/2020, Letnik:
80, Številka:
11
Journal Article
Recenzirano
Odprti dostop
Beginning with results for the leading-twist two-particle distribution amplitudes of
π
- and
K
-mesons, each of which exhibits dilation driven by the mechanism responsible for the emergence of ...hadronic mass, we develop parameter-free predictions for the pointwise behaviour of all
π
and
K
distribution functions (DFs), including glue and sea. The large-
x
behaviour of each DF meets expectations based on quantum chromodynamics; the valence-quark distributions match extractions from available data, including the pion case when threshold resummation effects are included; and at
ζ
5
=
5.2
GeV, the scale of existing measurements, the light-front momentum of these hadrons is shared as follows:
⟨
x
valence
⟩
π
=
0.41
(
4
)
,
⟨
x
glue
⟩
π
=
0.45
(
2
)
,
⟨
x
sea
⟩
π
=
0.14
(
2
)
; and
⟨
x
valence
⟩
K
=
0.42
(
3
)
,
⟨
x
glue
⟩
K
=
0.44
(
2
)
,
⟨
x
sea
⟩
K
=
0.14
(
2
)
. The kaon’s glue and sea distributions are similar to those in the pion, although the inclusion of mass-dependent splitting functions introduces some differences on the valence-quark domain. This study should stimulate improved analyses of existing data and motivate new experiments sensitive to all
π
and
K
DFs. With little known empirically about the structure of the Standard Model’s (pseudo-) Nambu-Goldstone modes and analyses of existing, limited data being controversial, it is likely that new generation experiments at upgraded and anticipated facilities will provide the information needed to resolve the puzzles and complete the picture of these complex bound states.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
On mass and matter Roberts, Craig D.
AAPPS bulletin,
12/2021, Letnik:
31, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The visible Universe is largely characterised by a single mass scale, namely, the proton mass,
m
p
. Contemporary theory suggests that
m
p
emerges as a consequence of gluon self-interactions, which ...are a defining characteristic of quantum chromodynamics (QCD), the theory of strong interactions in the Standard Model. However, the proton is not elementary. Its mass appears as a corollary of other, more basic emergent phenomena latent in the QCD Lagrangian, e.g. generation of nuclear-size gluon and quark mass-scales, and a unique effective charge that may describe QCD interactions at all accessible momentum scales. These remarks are explained herein, and focusing on the distribution amplitudes and functions of
π
and
K
mesons, promising paths for their empirical verification are elucidated. Connected therewith, in anticipation that production of
J
/
ψ
-mesons using
π
and
K
beams can provide access to the gluon distributions in these pseudo-Nambu-Goldstone modes, predictions for all
π
and
K
distribution functions are provided at the scale
ζ
=
m
J
/
ψ
.
The Coupled Model
Intercomparison Project phase 6 (CMIP6) HighResMIP is a new experimental design for global
climate model simulations that aims to assess the impact of model horizontal
resolution on ...climate simulation fidelity. We describe a hierarchy of global
coupled model resolutions based on the Hadley Centre Global Environment Model 3 – Global Coupled vn 3.1 (HadGEM3-GC3.1) model that ranges from
an atmosphere–ocean resolution of 130 km–1∘ to 25 km–1∕12∘, all using the same forcings and initial conditions. In
order to make such high-resolution simulations possible, the experiments
have a short 30-year spinup, followed by at least century-long simulations
with constant forcing to assess drift. We assess the change in model biases as a function of both atmosphere and
ocean resolution, together with the effectiveness and robustness of this new
experimental design. We find reductions in the biases in top-of-atmosphere
radiation components and cloud forcing. There are significant reductions in
some common surface climate model biases as resolution is increased,
particularly in the Atlantic for sea surface temperature and precipitation,
primarily driven by increased ocean resolution. There is also a reduction in
drift from the initial conditions both at the surface and in the deeper
ocean at higher resolution. Using an eddy-present and eddy-rich ocean
resolution enhances the strength of the North Atlantic ocean circulation
(boundary currents, overturning circulation and heat transport), while an
eddy-present ocean resolution has a considerably reduced Antarctic
Circumpolar Current strength. All models have a reasonable representation of El Niño–Southern Oscillation. In general, the biases present after 30 years of simulations do not change character markedly over longer timescales,
justifying the experimental design.
Abstract Introduction During a pregnancy complicated by diabetes, the human placenta undergoes a number of functional and structural pathologic changes, such as increased placental weight and ...increased incidence of placental lesions including villous maturational defects and fibrinoid necrosis. The pathologic findings reported have differed among studies, potentially reflecting differences in type of diabetes, study methodology, or glycemic control of study participants. Alternatively, these discrepancies may represent different biologic adaptations to distinct metabolic diseases. Methods We conducted a comprehensive review of English language citations in Pubmed and Embase using the keywords “diabetes”, “placenta”, AND “pathology”. Abstracts were reviewed for relevance then full-text articles were reviewed in order to extract a comprehensive summary of current pathological findings associated with pregestational and gestational diabetes mellitus, as well as an understanding of the impact of glycemic control on placental pathology. Results Placental abnormalities most consistently associated with maternal diabetes are an increased incidence of villous immaturity, increased measures of angiogenesis, and increased placental weight. Conclusions The literature suggests that, despite similarities in placental abnormalities, differences in placental pathology may reflect differences in pathophysiology among different types of diabetes. Consequently, standardization of terminology used to define placental lesions is warranted. Moreover, further research is needed to investigate the impact of pathophysiology, glycemic control and clinical factors, such as infant sex, weight and race, on placental structure and function.
Physical inactivity, ambient air pollution and obesity are modifiable risk factors for non-communicable diseases, with the first accounting for 10% of premature deaths worldwide. Although community ...level interventions may target each simultaneously, research on the relationship between these risk factors is lacking.
After comparing spatial interpolation methods to determine the best predictor for particulate matter (PM2.5; PM10) and ozone (O3) exposures throughout the U.S., we evaluated the cross-sectional association of ambient air pollution with leisure-time physical inactivity among adults.
In this cross-sectional study, we assessed leisure-time physical inactivity using individual self-reported survey data from the Centers for Disease Control and Prevention's 2011 Behavioral Risk Factor Surveillance System. These data were combined with county-level U.S. Environmental Protection Agency air pollution exposure estimates using two interpolation methods (Inverse Distance Weighting and Empirical Bayesian Kriging). Finally, we evaluated whether those exposed to higher levels of air pollution were less active by performing logistic regression, adjusting for demographic and behavioral risk factors, and after stratifying by body weight category.
With Empirical Bayesian Kriging air pollution values, we estimated a statistically significant 16-35% relative increase in the odds of leisure-time physical inactivity per exposure class increase of PM2.5 in the fully adjusted model across the normal weight respondents (p-value<0.0001). Evidence suggested a relationship between the increasing dose of PM2.5 exposure and the increasing odds of physical inactivity.
In a nationally representative, cross-sectional sample, increased community level air pollution is associated with reduced leisure-time physical activity particularly among the normal weight. Although our design precludes a causal inference, these results provide additional evidence that air pollution should be investigated as an environmental determinant of inactivity.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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