Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9}  GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

Study of the Semileptonic Decay Λ_{c}^{+}→Λe^{+}ν_{e}

The study of the Cabibbo-favored semileptonic decay Λ_{c}^{+}→Λe^{+}ν_{e} is reported using a 4.5  fb^{-1} data sample of e^{+}e^{-} annihilations collected at center-of-mass energies ranging from 4.600 GeV to 4.699 GeV with the BESIII detector at the BEPCII collider. The branching fraction of the decay is measured to be B(Λ_{c}^{+}→Λe^{+}ν_{e})=(3.56±0.11_{stat}±0.07_{syst})%, which is the most precise measurement to date. Furthermore, we perform an investigation of the internal dynamics in Λ_{c}^{+}→Λe^{+}ν_{e}. We provide the first direct comparisons of the differential decay rate and form factors with those predicted from lattice quantum chromodynamics (LQCD) calculations. Combining the measured branching fraction with a q^{2}-integrated rate predicted by LQCD, we determine |V_{cs}|=0.936±0.017_{B}±0.024_{LQCD}±0.007_{τ_{Λ_{c}}}.

Measurement of the Absolute Branching Fraction and Decay Asymmetry of Λ→nγ

The radiative hyperon decay Λ→nγ is studied using (10087±44)×10^{6}  J/ψ events collected with the BESIII detector operating at BEPCII. The absolute branching fraction of the decay Λ→nγ is determined to be (0.832±0.038_{stat}±0.054_{syst})×10^{-3}, which is a factor of 2.1 lower and 5.6 standard deviations different than the previous measurement. By analyzing the joint angular distribution of the decay products, the first determination of the decay asymmetry α_{γ} is reported with a value of -0.16±0.10_{stat}±0.05_{syst}.

Observation of an Isoscalar Resonance with Exotic J^{PC}=1^{-+} Quantum Numbers in J/ψ→γηη^{'}

Using a sample of (10.09±0.04)×10^{9}  J/ψ events collected with the BESIII detector operating at the BEPCII storage ring, a partial wave analysis of the decay J/ψ→γηη^{'} is performed. The first observation of an isoscalar state with exotic quantum numbers J^{PC}=1^{-+}, denoted as η_{1}(1855), is reported in the process J/ψ→γη_{1}(1855) with η_{1}(1855)→ηη^{'}. Its mass and width are measured to be (1855±9_{-1}^{+6})  MeV/c^{2} and (188±18_{-8}^{+3})  MeV, respectively, where the first uncertainties are statistical and the second are systematic, and its statistical significance is estimated to be larger than 19σ.

Observation of an a_{0}-like State with Mass of 1.817 GeV in the Study of D_{s}^{+}→K_{S}^{0}K^{+}π^{0} Decays

Using e^{+}e^{-} annihilation data corresponding to an integrated luminosity of 6.32  fb^{-1} collected at center-of-mass energies between 4.178 and 4.226 GeV with the BESIII detector, we perform the first amplitude analysis of the decay D_{s}^{+}→K_{S}^{0}K^{+}π^{0} and determine the relative branching fractions and phases for intermediate processes. We observe an a_{0}-like state with mass of 1.817 GeV in its decay to K_{S}^{0}K^{+} for the first time. In addition, we measure the ratio {B[D_{s}^{+}→K[over ¯]^{*}(892)^{0}K^{+}]/B[D_{s}^{+}→K[over ¯]^{0}K^{*}(892)^{+}]} to be 2.35_{-0.23stat}^{+0.42}±0.10_{syst}. Finally, we provide a precision measurement of the absolute branching fraction B(D_{s}^{+}→K_{S}^{0}K^{+}π^{0})=(1.46±0.06_{stat}±0.05_{syst})%.

Patterns of anticoagulant prescribing and renal function changes in patients with atrial fibrillation

Background

The prevalence of atrial fibrillation (AF) is nearly three times higher in patients with chronic kidney disease (CKD) than the general population. These patients have an increased risk of stroke and systemic thromboembolism (SSE) as well as bleeding. The role for direct oral anticoagulants (DOACs) in those with advanced CKD and AF remains controversial. Studies show that patients on DOACs for AF with advanced CKD have similar risk of SSE and bleeding compared to those on warfarin, but these failed to account for changes in renal function over time.

Purpose

We sought to evaluate the pattern of oral anticoagulant prescribing, class switching, discontinuation and renal function trajectory in patients with AF in the last decade, coinciding with the development of DOACs.

Methods

Using linked administrative databases, we assessed patients 66 years of age and older with a new diagnosis of non-valvular AF between April 1, 2012 and March 31, 2020 who were started on oral anticoagulation within 90 days of diagnosis. Participants required a baseline serum creatinine (Cr) measurement in the year preceding AF diagnosis. Cr values were used to calculate the estimated glomerular filtration rate (eGFR) using the CKD Epidemiology Collaboration equation. Kidney function was tracked at baseline and longitudinally among patients prescribed DOACs versus warfarin using the Laboratories Information System. Anticoagulant class switching was tracked and discontinuation was defined if a new prescription for anticoagulation was not filled after 90 days of their last prescription ending.

Results

A total of 57,574 participants were included in the study; 48,662 were started on DOACs and 8,912 were started on warfarin. In April 2012, 83.8% of patients were prescribed warfarin; however, the proportion of first prescriptions significantly evolved over time to DOACs (Figure 1). Of those started on DOACs, 13,383 (27.5%) discontinued therapy, 34,918 (71.8%) remained on therapy and 361 (0.7%) switched to warfarin. The rate of discontinuation among those started on warfarin was higher with 4,144 (46.5%) stopping, 3,172 (35.6%) continuing therapy and 1,596 (17.9%) switching to DOACs. Most patients (75.6%) who switched to DOACs from warfarin remained on DOACs until the occurrence of dialysis, renal transplantation, death, or the last follow-up date (March 31, 2020). At baseline, the mean eGFR in the warfarin group was 56.2 compared with 66.3 mL/min/1.73 m2 in the DOAC group (p<0.01). Over the course of study, more than half of the subjects in both groups had a 20% or more decline in eGFR (Figure 2).

Conclusion

Given the degree of renal function decline and frequency of anticoagulant class switching in our cohort, existing observational studies comparing DOACs to warfarin in patients with AF and CKD may be limited. In order to better compare DOACs to warfarin in this population, time-varying covariates like renal function should be included in modelling.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): CIHR Foundation Grant

Precise Measurements of Decay Parameters and CP Asymmetry with Entangled Λ-Λ[over ¯] Pairs

Based on 10 billion J/ψ events collected at the BESIII experiment, a search for CP violation in Λ decay is performed in the difference between CP-odd decay parameters α_{-} for Λ→pπ^{-} and α_{+} for Λ[over ¯]→p[over ¯]π^{+} by using the process e^{+}e^{-}→J/ψ→ΛΛ[over ¯]. With a five-dimensional fit to the full angular distributions of the daughter baryon, the most precise values for the decay parameters are determined to be α_{-}=0.7519±0.0036±0.0024 and α_{+}=-0.7559±0.0036±0.0030, respectively. The Λ and Λ[over ¯] averaged value of the decay parameter is extracted to be α_{avg}=0.7542±0.0010±0.0024 with unprecedented accuracy. The CP asymmetry A_{CP}=(α_{-}+α_{+})/(α_{-}-α_{+}) is determined to be -0.0025±0.0046±0.0012, which is one of the most precise measurements in the baryon sector. The reported results for the decay parameter will play an important role in the studies of the polarizations and CP violations for the strange, charmed and beauty baryons.

First Observation of the Direct Production of the χ_{c1} in e^{+}e^{-} Annihilation

We study the direct production of the J^{PC}=1^{++} charmonium state χ_{c1}(1P) in electron-positron annihilation by carrying out an energy scan around the mass of the χ_{c1}(1P). The data were collected with the BESIII detector at the BEPCII collider. An interference pattern between the signal process e^{+}e^{-}→χ_{c1}(1P)→γJ/ψ→γμ^{+}μ^{-} and the background processes e^{+}e^{-}→γ_{ISR}J/ψ→γ_{ISR}μ^{+}μ^{-} and e^{+}e^{-}→γ_{ISR}μ^{+}μ^{-} is observed by combining all the data samples. The χ_{c1}(1P) signal is observed with a significance of 5.1σ. This is the first observation of a C-even state directly produced in e^{+}e^{-} annihilation. The electronic width of the χ_{c1}(1P) resonance is determined to be Γ_{ee}=(0.12_{-0.08}^{+0.13})  eV, which is of the same order of magnitude as theoretical calculations.

Evidence for a Neutral Near-Threshold Structure in the K_{S}^{0} Recoil-Mass Spectra in e^{+}e^{-}→K_{S}^{0}D_{s}^{+}D^{*-} and e^{+}e^{-}→K_{S}^{0}D_{s}^{*+}D^{-}

We study the processes e^{+}e^{-}→K_{S}^{0}D_{s}^{+}D^{*-} and e^{+}e^{-}→K_{S}^{0}D_{s}^{*+}D^{-}, as well as their charge conjugated processes, at five center-of-mass energies between 4.628 and 4.699 GeV, using data samples corresponding to an integrated luminosity of 3.8  fb^{-1} collected by the BESIII detector at the BEPCII storage ring. Based on a partial reconstruction technique, we find evidence of a structure near the thresholds for D_{s}^{+}D^{*-} and D_{s}^{*+}D^{-} production in the K_{S}^{0} recoil-mass spectrum, which we refer to as the Z_{cs}(3985)^{0}. Fitting with a Breit-Wigner line shape, we find the mass of the structure to be (3992.2±1.7±1.6)  MeV/c^{2} and the width to be (7.7_{-3.8}^{+4.1}±4.3)  MeV, where the first uncertainties are statistical and the second are systematic. The significance of the Z_{cs}(3985)^{0} signal is found to be 4.6σ including both the statistical and systematic uncertainty. We report the Born cross section multiplied by the branching fraction at different energy points. The mass of the Z_{cs}(3985)^{0} is close to that of the Z_{cs}(3985)^{+}. Assuming SU(3) symmetry, the cross section of the neutral channel is consistent with that of the charged one. Hence, we conclude that the Z_{cs}(3985)^{0} is the isospin partner of the Z_{cs}(3985)^{+}.

Observation of Resonance Structures in e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) and Mass Measurement of ψ_{2}(3823)

Using a data sample corresponding to an integrated luminosity of 11.3  fb^{-1} collected at center-of-mass energies from 4.23 to 4.70 GeV with the BESIII detector, we measure the product of the e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) cross section and the branching fraction B[ψ_{2}(3823)→γχ_{c1}]. For the first time, resonance structure is observed in the cross section line shape of e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) with significances exceeding 5σ. A fit to data with two coherent Breit-Wigner resonances modeling the sqrt[s]-dependent cross section yields M(R_{1})=4406.9±17.2±4.5  MeV/c^{2}, Γ(R_{1})=128.1±37.2±2.3  MeV, and M(R_{2})=4647.9±8.6±0.8  MeV/c^{2}, Γ(R_{2})=33.1±18.6±4.1  MeV. Though weakly disfavored by the data, a single resonance with M(R)=4417.5±26.2±3.5  MeV/c^{2}, Γ(R)=245±48±13  MeV is also possible to interpret data. This observation deepens our understanding of the nature of the vector charmoniumlike states. The mass of the ψ_{2}(3823) state is measured as (3823.12±0.43±0.13)  MeV/c^{2}, which is the most precise measurement to date.

Observation of a State X(2600) in the π^{+}π^{-}η' System in the Process J/ψ→γπ^{+}π^{-}η'

Based on (10087±44)×10^{6}  J/ψ events collected with the BESIII detector, the process J/ψ→γπ^{+}π^{-}η^{'} is studied using two largest decay channels of the η^{'} meson, η^{'}→γπ^{+}π^{-} and η^{'}→ηπ^{+}π^{-}, η→γγ. A new resonance, which we denote as the X(2600), is observed with a statistical significance larger than 20σ in the π^{+}π^{-}η^{'} invariant mass spectrum, and it has a connection to a structure around 1.5  GeV/c^{2} in the π^{+}π^{-} invariant mass spectrum. A simultaneous fit on the π^{+}π^{-}η^{'} and π^{+}π^{-} invariant mass spectra with the two η^{'} decay modes indicates that the mass and width of the X(2600) state are 2618.3±2.0_{-1.4}^{+16.3}  MeV/c^{2} and 195±5_{-17}^{+26}  MeV, where the first uncertainties are statistical, and the second systematic.

Observation of J/ψ Electromagnetic Dalitz Decays to X(1835), X(2120), and X(2370)

Using a sample of about 10^{10}  J/ψ events collected at a center-of-mass energy sqrt[s]=3.097  GeV with the BESIII detector, the electromagnetic Dalitz decays J/ψ→e^{+}e^{-}π^{+}π^{-}η^{'}, with η^{'}→γπ^{+}π^{-} and η^{'}→π^{+}π^{-}η, have been studied. The decay J/ψ→e^{+}e^{-}X(1835) is observed with a significance of 15σ, and also an e^{+}e^{-} invariant-mass dependent transition form factor of J/ψ→e^{+}e^{-}X(1835) is presented for the first time. The intermediate states X(2120) and X(2370) are also observed in the π^{+}π^{-}η^{'} invariant-mass spectrum with significances of 5.3σ and 7.3σ. The corresponding product branching fractions for J/ψ→e^{+}e^{-}X, X→π^{+}π^{-}η^{'} [X=X(1835), X(2120), and X(2370)] are reported.

Small molecule-mediated rapid maturation of human induced pluripotent stem cell derived cardiomyocytes

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): Gravitation Program “Materials Driven Regeneration” by the Netherlands Organization for Scientific Research (RegmedXB #024.003.013) and the Marie Skłodowska-Curie Actions (Grant agreement RESCUE #801540). The EU-funded project BRAV3 (H2020, ID:874827)

Background

Human-induced pluripotent stem cell (iPSC)-derived cardiomyocytes (iPSC-CMs) do not display all hallmarks of mature human primary cardiomyocytes: the ability to use fatty acids as an energy source, high mitochondrial mass, increased nuclei polyploidism, synchronized electrical conduction, and forceful contractions. Instead, their phenotype is similar to immature cardiomyocytes in the late fetal stage. This immaturity represents a bottleneck to their application in 1) disease modeling – as most cardiac (genetic) diseases have a middle-age onset – and 2) clinical use, where integration and functional coupling are key. So far, the mainly used methods to enhance iPSC-CM maturation include prolonged time-in-culture, 3D culture, cyclic mechanical stretch, and electrical stimulation with specialized media. However, these protocols are laborious, costly, and not easily scalable.

Methods

In this study, we developed a simple, low cost, and rapid protocol using two peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1A/PGC-1α) activating small molecules: Asiatic Acid (AA) and GW501516 (GW) to promote cardiomyocyte maturity by inducing a metabolic switch to fatty acid utilization and increased mitochondrial biogenesis.

Results

Monolayers of iPSC-CMs were incubated with AA and GW every other day for 10 days resulting in increased expression of fatty acid-metabolism-related genes (5 and 10-fold increase in CPT1B gene expression, respectively), mitochondria biogenesis (protein expression of ATP5A) and fusion (50 and 100-fold increase in OPA1 gene expression, respectively). In addition, AA treated iPSC-CMs responded in the seahorse mitochondria stress test more rapidly to an artificial increase in mitochondrial activity and showed a higher flexibility in substrate utilization in the seahorse stress test. A more mature electrophysiological functionality was shown by increased ion channel gene expression (KCNA4, SCN5A, GJA1, CACNA1C, and SCN1B) and enhanced synchronous contraction in treated samples. Moreover, maturation was further shown by increased sarcomeric gene expression (5 and 7-fold increase in TNNI3 in AA and GW respectively) and nuclear polyploidism (>4N fold 2.16 and 1.48-fold increase in AA and GW respectively).

Conclusions

Collectively, these findings show that AA and GW trigger a metabolic switch and induce extensive maturation of iPSC-CMs, providing a rapid and cost-effective method to obtain iPSC-CMs that more closely resemble their adult counterparts.

E2F7/8 is involved in cardiomyocyte polyploidy but does not affect myocardial reperfusion injury recovery

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): CSC fellowship

Background

Polyploidy cells consist of more than two complete sets of homologous chromosomes. Although a characteristic feature of cardiomyocytes and observed in all mammalian species, its molecular mechanism and biological functions are still unknown. Cardiomyocytes polyploidy in rodents occurs mainly through incomplete cytokinesis and increases with age. Studies have demonstrated that E2F7/8 transcription factors are key regulators of polyploidy in the liver and pancreas, however, it remains unclear if E2F7/8 control the generation of polyploidy cardiomyocytes and what the functional consequence is post-myocardial infarction (MI).

Methods

By using a tamoxifen inducible Cre/LoxP approach in new-born mice, we deleted E2F7/8 transcription factors ubiquitously and evaluated the biological significance of postnatal E2F7/8 loss. Mice underwent myocardial ischemia reperfusion injury (IRI) and heart function was assessed by 4D-echocardiography. Cardiomyocyte nucleus polyploidy was measured by FACS and microscope.

Results

Deficiency of E2F7/8 significantly suppress cardiomyocyte mononucleated and multinucleated polyploidy, as well as dramatically decreased hepatocytes polyploidy. E2F7/8 defect also led to a decrease in cardiac stress related marker lever such as ANP, BNP, MMP2, β-MHC/α-MHC and an increase in CD31 expression level. Surprisingly, E2F7/8 deletion did not have impact on cardiac function and dimensions post-IRI.

Conclusion

In summary, we identified that E2F7/8 activity is involved in the cellular polyploidy in the heart but did not affect myocardial function after myocardial injury.

POS1406 EVALUATING THE QUALITY OF CARE FOR HEART FAILURE HOSPITALIZATIONS IN INFLAMMATORY ARTHRITIS- A POPULATION-BASED COHORT STUDY

Background

Individuals with inflammatory arthritis (IA) have an increased risk of heart failure (HF). Little is known if the quality of HF care differs among patients with IA compared to other chronic diseases such as diabetes mellitus (DM).

Objectives

We examined adherence to quality-of-care indicators for HF hospitalizations among patients with IA compared to those with DM but no IA and the general population (without IA or DM).

Methods

We linked multiple population-based health datasets to construct a cohort of adults living in Ontario, Canada on January 1, 2011 and followed to December 2020. The IA cohort was identified using validated case definitions and included patients with rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis. Comparison cohorts included adults with DM but no IA and general comparators without DM or IA. We included all subjects with a first HF hospitalization and who were alive at the time of discharge. We summarized the percentage of subjects in each of the 3 exposure groups who achieved recommended quality process measures [1]: (1) % receiving echocardiogram, (2) % receiving electrocardiogram, (3) % receiving a chest x-ray; and (4) % seen by a physician within 7 days of discharge. For those over the age of 65 years in whom medication information was universally available, we examined how many were dispensed evidence-based therapies: (5) % prescribed β-blocker, (6) % prescribed angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, (7) % prescribed mineralocorticoid receptor antagonist. We categorized adherence as perfect, moderate, or poor based on the number of measures achieved and compared proportions using pair-wise chi-squared tests.

Results

A first HF hospitalization occurred in 5,836 IA patients, 33,553 DM patients and 62,256 general comparators. The crude incidence rate for HF in IA was 2.70 per 1000/PY and was significantly higher compared to the general population (0.84 per 1000/PY), but lower compared to the DM cohort (5.01 per 1000/PY, p< 0.001). Mean age at time of HF hospitalization was significantly higher in the IA group (78 years) with more females affected (58%) compared to either the DM or general population group (p<0.001). All groups had high achievement of testing process measures and there were no differences in perfect adherence between the IA vs. DM and IA vs. general population comparators (Table 1). For those >65 years of age, patients with IA were less likely to achieve perfect adherence for medication quality indicators compared to either the DM or general population.

Table 1.

Percentage in each of three exposure groups achieving the recommended HF quality measures.

Process MeasureIA GroupDM GroupGeneral Population1.Echocardiogram90.6%91.1%89.5%2.Electrocardiogram97.4%97.4%97.3%3.Chest x-ray99.7%99.6%99.6%4.Health care provider visit within 7 days of discharge39.0%38.9%38.7%Perfect Adherence (achieving 1, 2,3 and 4 above)33.0%33.0% (p=0.43, IA vs. DM)32.2% (p=0.15, IA vs general population)5.Beta-blocker prescribed64.8%70.5%66.6%6.Angiotensin-converting enzyme inhibitor or angiotensin receptor blocker prescribed54.8%61.3%56.2%7.Mineralocorticoid receptor antagonist prescribed20.3%19.9%21.2%Perfect Adherence (achieving 5, 6 and 7 above)10.6%12.0% (p=<0.001, IA vs. DM)12.0% (p=0.02, IA vs general population)

Conclusion

HF quality indicators are adhered to in a high proportion of patients with IA following HF hospitalization. However, reasons for lower HF medication prescribing in IA compared to other high-risk conditions, such as DM, requires further evaluation. It will also be important to determine if adherence to HF quality of care translates to reduced long-term outcomes such as repeat HF hospitalizations and cardiovascular mortality, which we are currently exploring.

References

[1]Ontario HQ. Recommendations for Adoption: Heart Failure Care in the Community 2019 [Available from: http://www.hqontario.ca/Evidence-to-Improve-Care/Quality-Standards

Disclosure of Interests

Bindee Kuriya Speakers bureau: Abbvie, Gilead, Pfizer, Lihi Eder Speakers bureau: Abbvie, UCB, Pfizer, Eli Lily, Novartis and Sandoz, Jessica Widdifield: None declared, Laura Ferreira-Legere: None declared, Irene JH Jeong: None declared, Jiming Fang: None declared, Anna Chu: None declared, Jacob Udell: None declared

The prognosis value of proteasome activator subunit 3 expression in gastric cancer

Gastric cancer (GC) is a highly aggressive malignant tumor, and, therefore, the prognosis evaluation of this disease is important. Proteasome activator subunit 3 (PSME3) is highly expressed in GC; however, its exact role in GC has yet to be clarified. The gene expression profiles for GC were downloaded to find a candidate prognostic biomarker, and PSME3 was selected. The expression level of the PSME3 gene in GC tissues was analyzed using a public database. The biological processes and signal pathways that PSME3 was involved in were further analyzed. Immunohistochemical staining of 181 GC tissues was performed to detect the expression of the PSME3 protein. The correlation between PSME3 expression and GC prognosis and its clinical and pathological parameters were investigated. It was found that PSME3 mRNA expression was higher in GC than in adjacent gastric tissues, and high PSME3 expression was significantly correlated with tumor stage, histological subtype, lymph node metastasis status, and Helicobacter pylori infection in patients with GC (all p<0.01). Bioinformatics showed that PSME3 mainly played an oncogenic role in the development of GC by regulating the cell cycle and inhibiting apoptosis. The PSME3 protein was overexpressed in 64.6% (117/181) of the analyzed samples, and overexpression of PSME3 was associated with a significantly poor prognosis. In addition, multivariate analysis suggested that PSME3 overexpression, tumor, node, metastasis stage, and tumor size are independent prognostic biomarkers for GC. We conclude that the overexpression of PSME3 was associated with a poor prognosis in patients with GC, and PSME3 might play an oncogenic role in the occurrence and development of GC.

Probing CP symmetry and weak phases with entangled double-strange baryons

Though immensely successful, the standard model of particle physics does not offer any explanation as to why our Universe contains so much more matter than antimatter. A key to a dynamically generated matter-antimatter asymmetry is the existence of processes that violate the combined charge conjugation and parity (CP) symmetry1. As such, precision tests of CP symmetry may be used to search for physics beyond the standard model. However, hadrons decay through an interplay of strong and weak processes, quantified in terms of relative phases between the amplitudes. Although previous experiments constructed CP observables that depend on both strong and weak phases, we present an approach where sequential two-body decays of entangled multi-strange baryon-antibaryon pairs provide a separation between these phases. Our method, exploiting spin entanglement between the double-strange Ξ- baryon and its antiparticle2 [Formula: see text], has enabled a direct determination of the weak-phase difference, (ξP - ξS) = (1.2 ± 3.4 ± 0.8) × 10-2 rad. Furthermore, three independent CP observables can be constructed from our measured parameters. The precision in the estimated parameters for a given data sample size is several orders of magnitude greater than achieved with previous methods3. Finally, we provide an independent measurement of the recently debated Λ decay parameter αΛ (refs. 4,5). The [Formula: see text] asymmetry is in agreement with and compatible in precision to the most precise previous measurement4.

Observation of the Singly Cabibbo Suppressed Decay Λ_{c}^{+}→nπ^{+}

The singly Cabibbo-suppressed decay Λ_{c}^{+}→nπ^{+} is observed for the first time with a statistical significance of 7.3σ by using 3.9  fb^{-1} of e^{+}e^{-} collision data collected at center-of-mass energies between 4.612 and 4.699 GeV with the BESIII detector at BEPCII. The branching fraction of Λ_{c}^{+}→nπ^{+} is measured to be (6.6±1.2_{stat}±0.4_{syst})×10^{-4}. By taking the upper limit of branching fractions of Λ_{c}^{+}→pπ^{0} from the Belle experiment, the ratio of branching fractions between Λ_{c}^{+}→nπ^{+} and Λ_{c}^{+}→pπ^{0} is calculated to be larger than 7.2 at the 90% confidence level, which disagrees with most predictions of the available phenomenological models. In addition, the branching fractions of the Cabibbo-favored decays Λ_{c}^{+}→Λπ^{+} and Λ_{c}^{+}→Σ^{0}π^{+} are measured to be (1.31±0.08_{stat}±0.05_{syst})×10^{-2} and (1.22±0.08_{stat}±0.07_{syst})×10^{-2}, respectively, which are consistent with previous results.

MicroRNA-29a-3p regulates chemosensitivity in hypopharyngeal carcinoma via targeting Cdc42

INTRODUCTION

Hypopharyngeal carcinoma is one kind of high malignant tumour followed by poor prognosis in head and neck carcinomas. This study aimed to detect miR-29a-3p and Cdc42 in patients with hypopharyngeal carcinoma.

MATERIALS AND METHODS

The expression of miR-29a-3p and Cdc42 mRNA were detected, and the correlation between miR-29a-3p/Cdc42 and clinical stages was investigated.

RESULTS

The relative expression of miR-29a-3p in stage II, III and IV hypopharyngeal carcinoma tissues was significantly lower than that of stage I (P< 0.05). The relative expression of Cdc42 mRNA in stage I, III and IV tissues was significantly higher than that of stage I (P< 0.05). The expression of miR-29a-3p in hypopharyngeal carcinoma with lymph node metastasis was significantly lower than that without lymph node metastasis (P = 0.045).

CONCLUSION

MiR-29a-3p and Cdc42 mRNA could be potential diagnostic biomarkers of hypopharyngeal carcinoma.

[Management of the nondisplaced type Herbert D1 scaphoid fracture with robot navigation combined with wrist arthroscopy]

To investigate the feasibility and the clinical efficiency of robot navigation combined with wrist arthroscopy in minimally invasive treatment of nondisplaced type Herbert D1 scaphoid fracture. A retrospective analysis was performed on 9 patients who underwent nondisplaced type Herbert D1 scaphoid fracture in Xuzhou Renci Hospital from December 2019 to January 2021. Before the operation and at the last follow-up, grip strength, pinching force, modified wrist Mayo score and visual analogue scale (VAS) of wrist pain were recorded and compared. The average follow-up time was 14.1 months (7.5-24.0 months). All the fractures achieved primary healing after an average of 13.3 weeks (10-18 weeks). The average flexion and dorsal extension activity of the injured wrist was 51.2°±9.4°, 68.0°±7.3°, and the radial and ulnar deviation was 19.3°±6.2°, 45.7°±7.8°, respectively. At the final follow-up, there were statistically significant differences in grip strength, pinch strength, wrist Mayo score and VAS when compared with those before the operation (all P<0.05). The results demonstrated that robot navigation combined with wrist arthroscopy for nondisplaced type Herbert D1 scaphoid fracture is effective and minimally invasive with a short recovery time and satisfactory healing rate.

Measurement of the Cross Section for e^{+}e^{-}→Hadrons at Energies from 2.2324 to 3.6710 GeV

Based on electron-positron collision data collected with the BESIII detector operating at the Beijing Electron-Positron Collider II storage rings, the value of R≡σ(e^{+}e^{-}→hadrons)/σ(e^{+}e^{-}→μ^{+}μ^{-}) is measured at 14 center-of-mass energies from 2.2324 to 3.6710 GeV. The resulting uncertainties are less than 3.0% and are dominated by systematic uncertainties.

[Effect of reducing-opioids consumption on postoperative delirium incidence in elderly patients after gastric cancer surgery]

Objective: To evaluate the effect of reducing-opioids on postoperative delirium (POD) incidence in elderly patients with gastric cancer surgery. Methods: From July 2016 to September 2021, 130 elderly patients undergoing scheduled gastric cancer surgery in Zhejiang Cancer Hospital were selected and divided into conventional opioid general anesthesia group (group A) and reducing-opioids general anesthesia group (group B) according to random number table. Postoperative analgesic pump formula: group A: 0.2% ropivacaine and 1 μg/ml sufentanil solution; Group B: 0.2% ropivacaine solution. POD assessment was performed once daily between 8 am and 8 pm for 3 days after surgery. The primary outcome measures were POD incidence 3 days after surgery, and the secondary outcome measures included anaesthesia related adverse events 3 days after surgery, such as nausea and vomiting, postoperative fever and fatigue. Results: Among the 130 patients, 7 patients were excluded because they did not comply with the POD test after operation. Finally, 123 elderly patients completed the study. There were 59 cases in group A, aged (73±5) years, including 45 males, and 64 cases in group B, aged (71±6) years, including 56 males. The incidence of total POD 3 days after surgery in group A and B was 30.5% (18/59) and 18.8% (12/64), respectively, with no statistical significance (P>0.05). However, POD incidence at 48 and 72 h after operation in group A [27.1% (16/59) and 16.9% (10/59)] was higher than that in group B [10.9% (8/64) and 4.7% (3/64), both P<0.05]. The incidence of nausea and vomiting in group A was higher than that in group B [15.3% (9/59) vs 1.6% (1/64), P<0.05]. Conclusion: Reducing-opioids consumption have no effect on the incidence of total POD 3 d after gastric cancer surgery in elderly patients, but can reduce the risk of POD 48-72 h after surgery.

Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

[Advancement in endovascular therapy of aortoiliac occlusive disease]

Aortoiliac occlusive disease (AIOD) refers to the stenosis and occlusion of the distal abdominal aorta and(or) bifurcation of the aortoiliac artery,which is mainly caused by atherosclerosis,leading to pelvic and lower limb ischemia.Open surgery has always been the main treatment for complex AIOD.However,in recent years,with the development of endovascular surgery technologies and medical instruments,its treatment concept has been greatly changed.More and more clinical evidence has proved that the long-term efficacy of endovascular therapy is not inferior to that of traditional open surgery,so minimally invasive endovascular therapy has become the preferred treatment for AIOD.

First Measurement of Polarizations in the Decay D^{0}→ωφ

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} collected at a center-of-mass energy sqrt[s]=3.773  GeV by the BESIII detector, the decay D^{0}→ωϕ is observed for the first time. The branching fraction is measured to be (6.48±0.96±0.40)×10^{-4} with a significance of 6.3σ, where the first and second uncertainties are statistical and systematic, respectively. An angular analysis reveals that the ϕ and ω mesons from the D^{0}→ωϕ decay are transversely polarized. The 95% confidence level upper limit on longitudinal polarization fraction is set to be less than 0.24, which is inconsistent with current theoretical expectations and challenges our understanding of the underlying dynamics in charm meson decays.

Aluminum chloride induces G0/G1 phase arrest via regulating the reactive oxygen species-depended non-canonical STAT1 pathway in hFOB1.19 cells

Treatment with aluminum chloride (AlCl₃) suppresses the growth of osteoblastic cells; however, the molecular mechanisms underlying the impact of AlCl₃ on cell growth have not been fully characterized. In this study, we observed that exposure of hFOB1.19 cells to AlCl₃ arrested cells at G₀/G₁ phase by inducing p21 expression. Further studies indicated that AlCl₃ upregulated the phosphorylation level of signal transducer and activator of transcription 1 (STAT1) at serine 727 site (Ser727). By chromatin immunoprecipitation and electrophoretic mobility shift assay, we found that AlCl₃ promoted STAT1/DNA binding activity to p21 promoter, thus resulting in the upregulation of p21. Moreover, siRNA-mediated knockdown of STAT1 attenuated p21 level induced by AlCl₃. Notably, using hFOB1.19 cells stably expressing dominant-negative STAT1 (Ser727Ala), we demonstrated that phosphorylation of STAT1 at Ser727 site is required for p21-mediated cycle arrest induced by AlCl₃. Mechanism investigation indicated that AlCl₃ stimulated the phosphorylation of JNK, and administration of JNK inhibitor SP600125 prevented AlCl₃-induced G₀/G₁ arrest through suppressing the phosphorylation of STAT1. Notably, pretreatment with N-acetyl-cysteine, a reactive oxygen species scavenger, conferred a significantly inhibitory effect on AlCl₃-mediated activation of JNK/STAT1 signaling pathway. Taken together, our findings provide the molecular mechanism for G₀/G₁ arrest induced by AlCl₃ in osteoblastic cells.

[Drug-coated balloons versus bare metal stent for treatment of femoropopliteal lesions:36 month follow-up results of single center]

Objective: To examine the therapeutic effects of drug-coated balloon (DCB) and bare metal stent (BMS) on primary femoropopliteal disease (FPAD) in the real world. Methods: This was a retrospective analysis of single-center follow-up results at 12,24,and 36 months of patients with FPAD lesions that were treated with DCB and BMS at Department of Aortic and Vascular Surgery, Fu Wai Hospital.One-to-one propensity score matching(PSM) was performed to balance the covariance between DCB group (137 cases) and BMS group (100 cases). Freedom from clinically driven target lesion reintervention rate(fCD-TLR) was determined by Kaplan-Meier curve.Log-rank test was used to compare the rates of fCD-TLR between DCB and BMS groups at 12,24,36 months post-operation. Results: After PSM, there were both 71 patients in each group,aged (68.0±9.6) years(range: 46 to 90 years) and (68.8±7.3) years(range: 48 to 87 years),lesion lengths were (119.6±14.2)mm(range:40 to 380 mm) and (110.8±13.1)mm(range:40 to 400 mm). The median follow-up period were 24.3 months (range:5.8 to 55.1 months).There was no death,amputation or reintervention within the 30 days after operation.The rates of fCD-TLR for DCB group at 12,24 and 36 months were 97.2%,85.9%,69.1%, and 95.8%,83.1%,59.2% for BMS group.There was no statistical difference between the two groups by Log-rank test (P=0.551). Conclusion: DCB and BMS can both maintain favorable clinical effects in FPAD patients at 12,24,36 months post-operation.

Measurement of the Absolute Branching Fraction of D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}

Using a dataset of 6.32  fb^{-1} of e^{+}e^{-} annihilation data collected with the BESIII detector at center-of-mass energies between 4178 and 4226 MeV, we have measured the absolute branching fraction of the leptonic decay D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}, and find B_{D_{s}^{+}→τ^{+}ν_{τ}}=(5.27±0.10±0.12)×10^{-2}, where the first uncertainty is statistical and the second is systematic. The precision is improved by a factor of 2 compared to the previous best measurement. Combining with f_{D_{s}^{+}} from lattice quantum chromodynamics calculations or the |V_{cs}| from the CKMfitter group, we extract |V_{cs}|=0.978±0.009±0.012 and f_{D_{s}^{+}}=(251.1±2.4±3.0)  MeV, respectively. Combining our result with the world averages of B_{D_{s}^{+}→τ^{+}ν_{τ}} and B_{D_{s}^{+}→μ^{+}ν_{μ}}, we obtain the ratio of the branching fractions B_{D_{s}^{+}→τ^{+}ν_{τ}}/B_{D_{s}^{+}→μ^{+}ν_{μ}}=9.72±0.37, which is consistent with the standard model prediction of lepton flavor universality.