A
bstract
We propose a search for
B
meson decays to a baryon plus missing energy at the Belle II experiment to probe supersymmetry with a GeV-scale lightest neutralino
χ
~
1
0
and
R
-parity violation ...(RPV). We perform analytic computations of the signal branching fractions in the framework of effective field theory, with a single nonzero RPV operator
λ
ij
3
′
′
U
¯
i
c
D
¯
j
c
D
¯
3
c
, where
i, j
= 1
,
2. The hadronic form factors are calculated using an SU(3) phenomenological Lagrangian approach for the proton, as well as several hyperons and charmed baryons. Since the decay of the neutralino is kinematically and CKM suppressed in this theoretical scenario, it decays outside the detector and appears experimentally only as missing energy. We detail the analysis techniques at the experimental level and estimate the background in the
B
+
→
p
χ
~
1
0
search using published results for
B
+
→
K
+
ν
ν
¯
. Our final sensitivity plots are shown for both
λ
113
′
′
versus the squark mass
m
q
~
and
λ
113
′
′
/
m
q
~
2
versus the neutralino mass
m
χ
~
1
0
. We find that the search at Belle II could probe
λ
113
′
′
/
m
q
~
2
down to the order of 10
−
8
GeV
−
2
in the kinematically allowed
m
χ
~
1
0
range. We also obtain current limits on
λ
123
′
′
by recasting an existing search interpreted as
B
0
→
Λ
0
χ
~
1
0
, and comment about searches for
B
+
→
Σ
+
χ
~
1
0
,
B
0
→
Σ
0
χ
1
0
,
B
+
→
Λ
c
+
χ
~
1
0
, and
B
+
→
Ξ
c
+
χ
~
1
0
. In closing, we briefly discuss potential searches at the LHCb and BESIII experiments.
Long-lived light neutralinos at Belle II Dey, Sourav; Dib, Claudio O.; Helo, Juan Carlos ...
The journal of high energy physics,
02/2021, Letnik:
2021, Številka:
2
Journal Article
Recenzirano
Odprti dostop
A
bstract
We consider light neutralinos of mass about 1 GeV, produced from
τ
lepton rare decays at Belle II, in the context of R-parity-violating (RPV) supersymmetry. With large and clean samples of
...τ
leptons produced at the Belle II experiment, excellent sensitivity to such light neutralinos with the exotic signatures of displaced vertices is expected. We focus on two benchmark scenarios of single RPV operators,
λ
311
′
L
3
Q
1
D
¯
1
and
λ
312
′
L
3
Q
1
D
¯
2
, which induce both the production and decay of the lightest neutralino. For the reconstruction of a displaced vertex, we require at least two charged pions in the final states. We perform Monte-Carlo simulations for both signal and background events, and find that Belle II can explore regions in the parameter space competitive with other probes. In particular, for the
λ
311
′
scenario, it can put limits up to two orders of magnitude stronger than the current bounds.
We study the current estimates of
B
c
→
B
s
π
to extract the fragmentation fraction
f
c
/
f
s
at the LHCb. A rather robust estimate of
B
r
(
B
c
→
B
s
π
)
based on factorization and lattice results ...for the form factor gives
f
c
/
f
s
∼
0.056
with a 16% error. We also revisit the extraction of
f
s
/
f
d
using
B
→
D
π
instead of the theoretical cleaner but more suppressed channel
B
→
D
K
. We also find a tension on the predictions of
B
r
(
B
c
→
J
/
ψ
π
)
and
B
r
(
B
c
→
B
s
π
)
considering the measurements of these modes at LHCb, and find that, within a 23% uncertainty, only the lower end of the current prediction range
B
r
(
B
c
→
J
/
ψ
)
∼
0.4
%
-
1.7
%
would be consistent with the LHCb measurements.
Inhaling fine particles (particulate matter with diameter ≤ 2.5 μm; PM2.5) can induce oxidative stress and inflammation, and may contribute to onset of preterm labor and other adverse perinatal ...outcomes.
We examined whether outdoor PM2.5 was associated with adverse birth outcomes among 22 countries in the World Health Organization Global Survey on Maternal and Perinatal Health from 2004 through 2008.
Long-term average (2001-2006) estimates of outdoor PM2.5 were assigned to 50-km-radius circular buffers around each health clinic where births occurred. We used generalized estimating equations to determine associations between clinic-level PM2.5 levels and preterm birth and low birth weight at the individual level, adjusting for seasonality and potential confounders at individual, clinic, and country levels. Country-specific associations were also investigated.
Across all countries, adjusting for seasonality, PM2.5 was not associated with preterm birth, but was associated with low birth weight odds ratio (OR) = 1.22; 95% CI: 1.07, 1.39 for fourth quartile of PM2.5 (> 20.2 μg/m3) compared with the first quartile (< 6.3 μg/m3). In China, the country with the largest PM2.5 range, preterm birth and low birth weight both were associated with the highest quartile of PM2.5 only, which suggests a possible threshold effect (OR = 2.54; CI: 1.42, 4.55 and OR = 1.99; CI: 1.06, 3.72 for preterm birth and low birth weight, respectively, for PM2.5 ≥ 36.5 μg/m3 compared with PM2.5 < 12.5 μg/m3).
Outdoor PM2.5 concentrations were associated with low birth weight but not preterm birth. In rapidly developing countries, such as China, the highest levels of air pollution may be of concern for both outcomes.
CD8
T cells provide a critical defence from pathogens at mucosal epithelia including the female reproductive tract (FRT). Mucosal immunisation is considered essential to initiate this response, ...however this is difficult to reconcile with evidence that antigen delivered to skin can recruit protective CD8
T cells to mucosal tissues. Here we dissect the underlying mechanism. We show that adenovirus serotype 5 (Ad5) bio-distributes at very low level to non-lymphoid tissues after skin immunisation. This drives the expansion and activation of CD3
NK1.1
group 1 innate lymphoid cells (ILC1) within the FRT, essential for recruitment of CD8
T-cell effectors. Interferon gamma produced by activated ILC1 is critical to licence CD11b
Ly6C
monocyte production of CXCL9, a chemokine required to recruit skin primed CXCR3
CD8
T-cells to the FRT. Our findings reveal a novel role for ILC1 to recruit effector CD8
T-cells to prevent virus spread and establish immune surveillance at barrier tissues.
The role of the Therapy Radiographer/Radiation Therapist (TR/RTT) is to provide radiotherapy to patients with a cancer diagnosis. This includes, not only administration of treatment, but also ...management of side-effects and provision of support/care. Despite this role being consistent throughout Europe, there is currently no standardisation of education for TRs/RTTs. The SAFE EUROPE project aims to standardize TR/RTT education to enable ‘safe and free exchange’ of TRs/RTTs across Europe. Consequently, this study aims to explore patients' perspectives regarding the current skills and competencies of TRs/RTTs.
From May 2021 to February 2022, semi-structured interviews were conducted with patients who had recently received radiotherapy in the UK, Malta and Portugal. Ethical approval for this study was granted by the NHS Research Ethics Committee with additional local approvals obtained.
Forty-eight participants from the UK (n = 18), Portugal (n = 19), and Malta (n = 11) completed interviews. Participants described high satisfaction with TRs'/RTTs’ competence and skills in all three countries. The main theme arising from the analysis was the importance of trust building with TRs/RTTs. Six factors were identified as influencing levels of trust: communication; side-effect management; team consistency; relational skills; patient dignity; and competence. A small number of patients reported feeling rushed and not having their physical and emotional needs met by TRs/RTTs.
This multicentre study demonstrated that patients perceive TRs/RTTs in the UK, Malta and Portugal as highly competent and skilled. Practical recommendations are provided to address identified deficits in practice, which can be addressed through adaptation of TR/RTT education/training and clinical practice.
Recommendations arising from this study are important to ensure that TRs/RTTs have transferable skills that provide consistently high quality care to patients throughout Europe.
Cutaneous diseases (such as atopic dermatitis, acne, psoriasis, alopecia and chronic wounds) rank as the fourth most prevalent human disease, affecting nearly one-third of the world's population. ...Skin diseases contribute to significant non-fatal disability globally, impacting individuals, partners, and society at large. Recent evidence suggests that specific microbes colonising our skin and its appendages are often overrepresented in disease. Therefore, manipulating interactions of the microbiome in a non-invasive and safe way presents an attractive approach for management of skin and hair follicle conditions. Due to its proven anti-microbial and anti-inflammatory effects, blue light (380 - 495nm) has received considerable attention as a possible 'magic bullet' for management of skin dysbiosis. As humans, we have evolved under the influence of sun exposure, which comprise a significant portion of blue light. A growing body of evidence indicates that our resident skin microbiome possesses the ability to detect and respond to blue light through expression of chromophores. This can modulate physiological responses, ranging from cytotoxicity to proliferation. In this review we first present evidence of the diverse blue light-sensitive chromophores expressed by members of the skin microbiome. Subsequently, we discuss how blue light may impact the dialog between the host and its skin microbiome in prevalent skin and hair follicle conditions. Finally, we examine the constraints of this non-invasive treatment strategy and outline prospective avenues for further research. Collectively, these findings present a comprehensive body of evidence regarding the potential utility of blue light as a restorative tool for managing prevalent skin conditions. Furthermore, they underscore the critical unmet need for a whole systems approach to comprehend the ramifications of blue light on both host and microbial behaviour.
We analysed 1040 individual trees, located in 62 plots across the Amazon Basin for leaf mass per unit area (MA), foliar carbon isotopic composition (δ13C) and leaf level concentrations of C, N, P, ...Ca, Mg, K and Al. All trees were identified to the species level with the dataset containing 58 families, 236 genera and 508 species, distributed across a wide range of soil types and precipitation regimes. Some foliar characteristics such as MA, C, N and Mg emerge as highly constrained by the taxonomic affiliation of tree species, but with others such as P, K, Ca and δ13C also strongly influenced by site growing conditions. By removing the environmental contribution to trait variation, we find that intrinsic values of most trait pairs coordinate, although different species (characterised by different trait suites) are found at discrete locations along a common axis of coordination. Species that tend to occupy higher fertility soils are characterised by a lower MA and have a higher intrinsic N, P, K, Mg and δ13C than their lower fertility counterparts. Despite this consistency, different scaling patterns were observed between low and high fertility sites. Inter-relationships are thus substantially modified by growth environment. Analysing the environmental component of trait variation, we found soil fertility to be the most important predictor, influencing all leaf nutrient concentrations and δ13C and reducing MA. Mean annual temperature was negatively associated with leaf level N, P and K concentrations. Total annual precipitation positively influences MA, C and δ13C, but with a negative impact on Mg. These results provide a first basis for understanding the relationship between the physiological functioning and distribution of tree species across Amazonia.
Repeated long-term censuses have revealed large-scale spatial patterns in Amazon basin forest structure and dynamism, with some forests in the west of the basin having up to a twice as high rate of ...aboveground biomass production and tree recruitment as forests in the east. Possible causes for this variation could be the climatic and edaphic gradients across the basin and/or the spatial distribution of tree species composition. To help understand causes of this variation a new individual-based model of tropical forest growth, designed to take full advantage of the forest census data available from the Amazonian Forest Inventory Network (RAINFOR), has been developed. The model allows for within-stand variations in tree size distribution and key functional traits and between-stand differences in climate and soil physical and chemical properties. It runs at the stand level with four functional traits – leaf dry mass per area (Ma), leaf nitrogen (NL) and phosphorus (PL) content and wood density (DW) varying from tree to tree – in a way that replicates the observed continua found within each stand. We first applied the model to validate canopy-level water fluxes at three eddy covariance flux measurement sites. For all three sites the canopy-level water fluxes were adequately simulated. We then applied the model at seven plots, where intensive measurements of carbon allocation are available. Tree-by-tree multi-annual growth rates generally agreed well with observations for small trees, but with deviations identified for larger trees. At the stand level, simulations at 40 plots were used to explore the influence of climate and soil nutrient availability on the gross (ΠG) and net (ΠN) primary production rates as well as the carbon use efficiency (CU). Simulated ΠG, ΠN and CU were not associated with temperature. On the other hand, all three measures of stand level productivity were positively related to both mean annual precipitation and soil nutrient status. Sensitivity studies showed a clear importance of an accurate parameterisation of within- and between-stand trait variability on the fidelity of model predictions. For example, when functional tree diversity was not included in the model (i.e. with just a single plant functional type with mean basin-wide trait values) the predictive ability of the model was reduced. This was also the case when basin-wide (as opposed to site-specific) trait distributions were applied within each stand. We conclude that models of tropical forest carbon, energy and water cycling should strive to accurately represent observed variations in functionally important traits across the range of relevant scales.
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