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.

The DOMON domain protein LmKnk contributes to correct chitin content, pore canal formation and lipid deposition in the cuticle of Locusta migratoria during moulting

Insects prevent uncontrolled penetration of water and xenobiotics by producing an impermeable cuticle. The major component of the cuticle is chitin that adopts a crystalline structure thereby contributing to cuticle stability. Our understanding of the contribution of chitin to the cuticle barrier function is limited. Here, we studied the role of the DOMON domain protein Knickkopf (LmKnk) that is involved in chitin organization and cuticle permeability in the migratory locust Locusta migratoria. We show that LmKnk localizes to the chitin layer in the newly produced cuticle. Injection of double-stranded RNA targeting LmKnk (dsLmKnk) in locust nymphs caused failure of moulting to the next stage. Histological experiments revealed that apolysis, i.e., the detachment of the old cuticle from the body surface, was normal; however, the newly synthesized cuticle was thinner than the cuticle of the control insects. Indeed, chitin content dropped after suppression of LmKnk expression. As seen by transmission electron microscopy, crystalline chitin organization was lost in dsLmKnk-treated insects. In addition, the structure of pore canals, which are lipid transporting routes in the cuticle, was abnormal. Consistently, their content was reduced and, probably by consequence, lipid deposition on the cuticle was decreased after injection of dsLmKnk. Suppression of LmKnk transcript levels rendered L. migratoria more susceptible to each of four selected insecticides including malathion, chlorpyrifos, carbaryl and deltamethrin. Overall, our data show that LmKnk is needed for correct chitin amounts and organization, and their changes ultimately affect cuticular permeability in L. migratoria.

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.

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.

[Analysis of correlation factors of hyponatremia in elderly patients with hip fracture during perioperative period]

Objective: To examine the risk factors of hyponatremia during perioperative period for elderly hip fracture patients. Methods: Clinical data of 1 001 patients with hip fracture over 60 years old who received surgical treatment at Department of Orthopedics,Seventh Medical Center,People's Liberation Army General Hospital from January 2012 to December 2016 were retrospectively analyzed.There were 327 males and 674 females with a median age of 81 years (range: 60 to 104 years).There were 584 cases(58.34%) intertrochanteric fractures and 417 cases(41.65%) femoral neck fractures.Hyponatremia was defined as serum sodium concentration <135 mmol/L,and patients were divided into admission hyponatremia and postoperative hyponatremia according to the occurrence time of hyponatremia.Postoperative hyponatremia was divided into early postoperative hyponatremia (within 24 hours after surgery) and discharge hyponatremia (within 48 hours before discharge or death).Patients with hyponatremia can be divided into three types according to their condition changes:persistent hyponatremia,transient hyponatremia (hyponatremia on admission,but normal blood sodium after operation),and new postoperative hyponatremia (normal blood sodium on admission,hyponatremia after operation).The incidence rate,occurrence time and type of perioperative hyponatremia in elderly patients with hip fracture were analyzed,and univariate and multivariate Logistic regression analysis was used to examine the related factors of admission and postoperative hyponatremia. Results: Among 1 001 patients,126 patients (12.69%,126/1 001) had hyponatremia on admission,161 patients (16.3%,161/987) had hyponatremia after operation,140 patients (14.6%,140/960) had early postoperative hyponatremia,128 patients (14.0%,128/916) had discharge hyponatremia.Among the 916 patients with complete perioperative blood sodium concentration data,52 patients(5.7%) had persistent hyponatremia,64 patients(7.0%) had transient hyponatremia.Seventy-seven patients(8.4%) had new onset hyponatremia.Univariate analysis showed that age,male,intertrochanteric fracture of femur,white blood cell count,hemoglobin and albumin level were correlated with hyponatremia at admission (all P≤0.05). Hyponatremia at admission,dementia,and general anesthesia were associated with postoperative hyponatremia.Multivariate analysis showed that male(OR=1.788,95%CI:1.196 to 2.674,P=0.005) and white blood cell count(OR=1.116,95%CI:1.041 to 1.195,P=0.002) were independent risk factors for admission hyponatraemia,and albumin level(OR=0.932,95%CI:0.891 to 0.982,P=0.004) were protective factors, admission hyponatremia (OR=6.481,95%CI:4.125 to 10.182,P<0.01) was an independent risk factor for postoperative hyponatremia,while general anesthesia (OR=0.614,95%CI:0.383 to 0.986,P=0.044) was a protective factor. Conclusions: The incidence of hyponatremia in elderly hip fracture patients is high.Male and high level of white blood cell counts are independent risk factors for admission hyponatremia.High level of albumin is a protective factor for admission hyponatremia.Admission hyponatremia is an independent risk factor for postoperative hyponatremia,and general anesthesia is a protective factor for postoperative hyponatremia.

Low levels of organic compound trace elements improve the eggshell quality, antioxidant capacity, immune function, and mineral deposition of aged laying hens

In the egg production industry, trace elements are required as additional dietary supplements to play vital roles in performance and egg quality. Compared to inorganic microelements (ITs), appropriate dose of organic trace microelements (OTs) are environmentally friendly and sufficient to satisfy the needs of hens. In order to evaluate the extent to which low-dose OTs replace whole ITs, the effects of organic copper, zinc, manganese, and iron compound on the performance, eggshell quality, antioxidant capacity, immune function, and mineral deposition of old laying hens were investigated. A total of 1 080 57-week-old Jing Hong laying hens were assigned to five groups with six replicates of 36 layers each for an 8-week experimental period. The birds were fed either a basal diet (control treatment (CT)) or the basal diet supplemented with commercial levels of inorganic trace elements (IT 100%) or the equivalent organic trace elements at 20%, 30%, and 50% of the inorganic elements (OT 20%, OT 30%, and OT 50%, respectively). Results showed that compared with those in the CT treatment, feeding hens with inorganic or organic microelement diet had significant effects on the eggshell quality, antioxidant capacity, immune function, and mineral deposition of old laying hens (P < 0.05). The eggshell strength and ratio between OT 30%, OT 50%, and IT 100% were similar at weeks 4 and 8, and the eggshell thickness of these groups was also similar at weeks 6 and 8. At week 8, the eggshell colour in OT 50% was darker than that in IT 100%. The mineral content in the eggshells of OT 50% and IT 100% significantly increased (P < 0.001), with no significant difference in effective thickness, mammillary thickness, and mammillary knob width between groups. There were no differences in the malondialdehyde content, total antioxidant capacity, and total superoxide dismutase activity in serum between OT 30%, OT 50%, and IT100%. While the catalase activities, the interleukin-1β, interleukin-10, immunoglobulin G, and immunoglobulin M concentrations in serum were not significantly different between OT 50% and IT 100%. The mineral contents in the faeces of the organic groups were considerably reduced compared with those in IT 100% (P < 0.001). In conclusion, dietary supplementation with 30-50% organic compound microelements has the potential to replace 100% inorganic microelements in the hen industry for improving eggshell quality, mineral deposition in the eggshell, antioxidant capacity, and immune function, and reducing emissions to the environment without negative effects on laying performance.

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.

Effect of coronary disease characteristics on prognostic relevance of residual ischemia after stent implantation

Background

Although residual ischemia after revascularization is an important predictor of future cardiovascular events, its sensitivity and specificity to predict clinical events were relatively low, and data on which coronary disease characteristics affect prognostic implications of residual ischemia are limited.

Purpose

We aimed to investigate the influence of coronary disease characteristics on prognostic implications of residual ischemia after percutaneous coronary intervention (PCI).

Methods

This study included 1,476 patients with drug-eluting stent implantation and available pre- and post-PCI fractional flow reserve (FFR) measurements from the international post-PCI FFR registry (NCT04012281). Residual ischemia was defined as post-PCI FFR ≤0.80. Coronary disease characteristics with significant interaction hazard ratios (HRs) for clinical outcomes with residual ischemia were defined as interaction characteristics with residual ischemia (ICwRI). The primary outcome was target vessel failure (TVF)–a composite of cardiac death, target vessel myocardial infarction, and target vessel revascularization–at 2 years.

Results

The mean pre- and post-PCI FFR were 0.68±0.11 and 0.87±0.07, respectively. The 203 vessels (13.8%) with residual ischemia had higher risks of TVF compared to that for post-PCI FFR &gt;0.80 (HR 2.45, 95% confidence interval [CI] 1.50–4.00, P&lt;0.001). Among pre- and post-PCI angiographic characteristics, ICwRI with a significant interaction HR with residual ischemia (P&lt;0.10) included lesion length ≥40 mm, pre-PCI SYNTAX score &gt;17, and pre-PCI FFR ≤0.62 (Table). Each ICwRI had a direct prognostic effect not mediated by residual ischemia in mediation analysis. The association between an increased TVF risk and residual ischemia differed according to the number of ICwRI (p-for-interaction &lt;0.001). It was significant in patients with 0 or 1 ICwRI (HR 3.48, 95% CI 2.01–6.00, P&lt;0.001) but not in those with ≥2 ICwRI (HR 0.60, 95% CI 0.18–2.03, P=0.41) (Figure A). Compared to the residual ischemia group, patients without residual ischemia and those with 0 or 1 ICwRI showed a significantly lower risk of TVF (HR 0.32, 95% CI 0.19–0.54, P&lt;0.001), but those with ≥2 ICwRI had a similar risk of TVF as the residual ischemia group (HR 1.08, 95% CI 0.57–2.01, P=0.819) (Figure B). The prognostic impact of ≥2 ICwRI in patients without residual ischemia was consistent in all subgroups with different clinical characteristics.

Conclusions

Coronary disease characteristics including lesion length, SYNTAX score, and pre-PCI FFR affected the prognostic implications of residual ischemia. This prognostic relevance was attenuated in patients with multiple interacting characteristics. Therefore, comprehensive assessment of coronary disease characteristics with post-procedural coronary physiology can help better risk stratification and appropriate treatment planning after revascularization.

Funding Acknowledgement

Type of funding sources: None.

Observation of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e}

Using 2.93  fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at a center-of-mass energy of 3.773 GeV, the observation of the D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} semileptonic decay is presented. The statistical significance of the decay D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is greater than 10σ. The branching fraction of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is measured to be (1.09±0.13_{-0.16}^{+0.09}±0.12)×10^{-3}. Here, the first uncertainty is statistical, the second is systematic, and the third originates from the assumed branching fraction of K_{1}(1270)^{-}→K^{-}π^{+}π^{-}. The fraction of longitudinal polarization in D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is determined for the first time to be 0.50±0.19_{stat}±0.08_{syst}.

First Measurement of the Absolute Branching Fraction of Λ→pμ^{-}ν[over ¯]_{μ}

The absolute branching fraction of Λ→pμ^{-}ν[over ¯]_{μ} is reported for the first time based on an e^{+}e^{-} annihilation sample of 10×10^{9}  J/ψ events collected with the BESIII detector at sqrt[s]=3.097  GeV. The branching fraction is determined to be B(Λ→pμ^{-}ν[over ¯]_{μ})=[1.48±0.21(stat)±0.08(syst)]×10^{-4}, which is improved by about 30% in precision over the previous indirect measurements. Combining this result with the world average of B(Λ→pe^{-}ν[over ¯]_{e}), we obtain the ratio {[Γ(Λ→pμ^{-}ν[over ¯]_{μ})]/[Γ(Λ→pe^{-}ν[over ¯]_{e})]} to be 0.178±0.028, which agrees with the standard model prediction assuming lepton flavor universality. The asymmetry of the branching fractions of Λ→pμ^{-}ν[over ¯]_{μ} and Λ[over ¯]→p[over ¯]μ^{+}ν_{μ} is also determined, and no evidence for CP violation is found.

Effect of the COVID-19 pandemic on cardiac arrest resuscitation practices and outcomes in non-COVID-19 patients

The effect of changes to cardiopulmonary resuscitation (CPR) procedures in response to Coronavirus disease 2019 (COVID-19) on in-hospital cardiac arrest (IHCA) management and outcomes are unreported. In this multicenter retrospective study, we showed that median time to arrival of resuscitation team has increased and proportion of patients receiving first-responder CPR has lowered during this pandemic. IHCA during the pandemic was independently associated with lower return of spontaneous circulation OR 0.63 (95% CI 0.43–0.91), despite adjustment for lowered patient comorbidity and increased time to resuscitation team arrival. Changes to resuscitation practice in this pandemic had effects on IHCA outcomes, even in patients without COVID-19.

Direct Measurement of the Branching Fractions B(ψ(3686)→J/ψX) and B(ψ(3770)→J/ψX), and Observation of the State R(3760) in e^{+}e^{-}→J/ψX

We report a measurement of the observed cross sections of e^{+}e^{-}→J/ψX based on 3.21  fb^{-1} of data accumulated at energies from 3.645 to 3.891 GeV with the BESIII detector operated at the BEPCII collider. In analysis of the cross sections, we measured the decay branching fractions of B(ψ(3686)→J/ψX)=(64.4±0.6±1.6)% and B(ψ(3770)→J/ψX)=(0.5±0.2±0.1)% for the first time. The energy-dependent line shape of these cross sections cannot be well described by two Breit-Wigner (BW) amplitudes of the expected decays ψ(3686)→J/ψX and ψ(3770)→J/ψX. Instead, it can be better described with one more BW amplitude of the decay R(3760)→J/ψX. Under this assumption, we extracted the R(3760) mass M_{R(3760)}=3766.2±3.8±0.4  MeV/c^{2} , total width Γ_{R(3760)}^{tot}=22.2±5.9±1.4  MeV, and product of leptonic width and decay branching fraction Γ_{R(3760)}^{ee}B[R(3760)→J/ψX]=(79.4±85.5±11.7)  eV. The significance of the R(3760) is 5.3σ. The first uncertainties of these measured quantities are from fits to the cross sections and second systematic.

Dietary supplementation of methionine mitigates oxidative stress in broilers under high stocking density

We aimed to investigate whether dietary supplementation of methionine could mitigate intestinal oxidative injury in broilers under high stocking density (HSD). In the grower phase (d 22–42), 576 broilers with similar body weight were randomly chosen and divided into 8 groups in a 2 × 4 factorial experiment. Two different stocking densities (14 and 20 broilers per m²) were tested with 4 different methionine levels: 0.35%, 0.4%, 0.45%, or 0.5%. Intestinal morphological and oxidative stress markers were assessed at the end of the test period. The results showed that mortality of broilers was significantly higher in the HSD group fed 0.35% methionine diet than the other groups, which was reversed by supplementation with 0.40% to 0.50% methionine. HSD significantly decreased feed intake and daily weight gain. HSD treatment significantly decreased T-AOC, activity of GPX (P < 0.01) and increased the level of PCO (P < 0.01), MDA (P = 0.052) of plasma. The decreased glutathione peroxidase activity in the liver and jejunum caused by HSD was alleviated by additional methionine. Supplementation of methionine increased the ration of GSH/GSSG in the plasma. The jejunum villus height and ratio of villus height to crypt depth under low stocking density conditions with 0.40% methionine diet were the highest, whereas the 0.45% methionine group was the highest under HSD conditions. Thus, additional dietary supplementation of methionine mitigates oxidative stress in broilers under HSD conditions and 0.40% to 0.45% methionine can be applied in cage rearing broiler production for amelioration of oxidative stress caused by HSD.

Observation of a Near-Threshold Structure in the K^{+} Recoil-Mass Spectra in e^{+}e^{-}→K^{+}(D_{s}^{-}D^{*0}+D_{s}^{*-}D^{0})

We report a study of the processes of e^{+}e^{-}→K^{+}D_{s}^{-}D^{*0} and K^{+}D_{s}^{*-}D^{0} based on e^{+}e^{-} annihilation samples collected with the BESIII detector operating at BEPCII at five center-of-mass energies ranging from 4.628 to 4.698 GeV with a total integrated luminosity of 3.7  fb^{-1}. An excess of events over the known contributions of the conventional charmed mesons is observed near the D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0} mass thresholds in the K^{+} recoil-mass spectrum for events collected at sqrt[s]=4.681  GeV. The structure matches a mass-dependent-width Breit-Wigner line shape, whose pole mass and width are determined as (3982.5_{-2.6}^{+1.8}±2.1)  MeV/c^{2} and (12.8_{-4.4}^{+5.3}±3.0)  MeV, respectively. The first uncertainties are statistical and the second are systematic. The significance of the resonance hypothesis is estimated to be 5.3  σ over the contributions only from the conventional charmed mesons. This is the first candidate for a charged hidden-charm tetraquark with strangeness, decaying into D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0}. However, the properties of the excess need further exploration with more statistics.

Model-Independent Determination of the Spin of the Ω^{-} and Its Polarization Alignment in ψ(3686)→Ω^{-}Ω[over ¯]^{+}

We present an analysis of the process ψ(3686)→Ω^{-}Ω[over ¯]^{+} (Ω^{-}→K^{-}Λ, Ω[over ¯]^{+}→K^{+}Λ[over ¯], Λ→pπ^{-}, Λ[over ¯]→p[over ¯]π^{+}) based on a dataset of 448×10^{6}  ψ(3686) decays collected with the BESIII detector at the BEPCII electron-positron collider. The helicity amplitudes for the process ψ(3686)→Ω^{-}Ω[over ¯]^{+} and the decay parameters of the subsequent decay Ω^{-}→K^{-}Λ (Ω[over ¯]^{+}→K^{+}Λ[over ¯]) are measured for the first time by a fit to the angular distribution of the complete decay chain, and the spin of the Ω^{-} is determined to be 3/2 for the first time since its discovery more than 50 years ago.

[Clinical significance of hyponatremia in hip fracture in elderly patients]

Objective: To investigate the outcome of hip fracture patients associated with hyponatremia. Methods: From January 2012 to December 2016, the data of 1 001 elderly patients with hip fracture treated in the Seventh Medical Center of PLA General Hospital were analyzed retrospectively. According to the level of serum sodium, the patients were divided into hyponatremia group (sodium<135 mmol/L) and non-hyponatremia group (sodium≥135 mmol/L), in which≥130-135 mmol/L was mild hyponatremia, ≥125-130 mmol/L was moderate hyponatremia, and<125 mmol/L was severe hyponatremia. The length of hospital stay, incidence of complications and mortality were compared between patient with hyponatremia and without; and the above three indexes between patients with mild hyponatremia and moderate severe hyponatremia were also analyzed. Results: There were 126 patients with hyponatremia, including 98 with mild hyponatremia (9.8%, 98/1 001), 18 with moderate hyponatremia (1.8%, 18/1 001), and 10 with severe hyponatremia (1.0%, 10/1001); of those patients, there were 53 males and 73 females, aged 82(78, 87) years. There were 875 patients in non-hyponatremia group, including 274 males and 601 females, and aged 81(75, 85) years. The mortality of 30 days, 1 year and overall were 9.5% (12/126), 26.2% (33/126) and 40.5% (51/126) in hyponatremia group, 3.5% (31/875), 14.2% (124/875) and 27.7% (242/875) in non-hyponatremia group, respectively; the differences between the two groups were all statistically significant (χ²=9.583, 12.031, 9.839, all P<0.05). After adjusting the age, sex, fracture type and coexisting diseases, hyponatremia was an independent risk factor for 30 days, 1 year and overall mortality, the OR(95%CI) was 2.744(1.331-5.654), 1.975(1.251-3.119), 1.637(1.099-2.440), respectively (all P<0.05). The 30 days, 1 year and overall mortality for mild hyponatremia were 6.1%, 24.5% and 37.8%, respectively; and those were 21.4%, 32.1% and 50.0% in patients with moderate and severe hyponatremia, respectively; only the difference for 30 days mortality was statistically different between two groups (χ²=4.278, P=0.039). The length of hospital stay for mild hyponatremia patients were 11 (9,16) d, and it was 12(10,18) d in patients with moderate and severe hyponatremia patients, and there was no significant difference between the two groups (Z=1.613, P=0.107). The incidence of complications was 22.9% (200/875) in non-hyponatremia group and 32.5%(41/126) in hyponatremia group, and there was significant difference between the two groups (χ²=5.649, P=0.017). Conclusions: Compared with non-hyponatremia, patients with hyponatremia have higher incidence of perioperative complications, longer hospital stay and higher mortality. With the increasing degree of hyponatremia, the above indicators tend to be serious.

Asiatic Acid Induces Mitochondrial Apoptosis via Inhibition of JAK2/STAT3 Signalling Pathway in Human Osteosarcoma

Osteosarcoma (OS), a severe malignant bone tumour, usually occurs in adolescents and children and has a poor prognosis. Asiatic acid (AA), an active component isolated from Centella asiatica (L.) Urb., exhibits appreciable anti-oxidant and anti-tumour activities. So far, the effects and underlying mechanisms of AA against OS have not been clarified. Here, we explored the anti-tumour effects of AA against human OS and the involved mechanism mediating its actions. To evaluate effects of AA on the cell proliferation of human OS cells, cell viability and colony formation assays were performed. Flow cytometry was used to evaluate apoptosis in OS cells exposed to AA and mitochondrial membrane potential. Western blotting and RT-PCR were applied to determine expression of the relevant proteins and their mRNA levels. Our explorations showed that AA inhibits proliferation of human OS cells in a concentration- and time-dependent manner, and induces apoptosis of OS cells by the intrinsic (mitochondrial) pathway. Importantly, we found that inhibition of the AA-induced phosphorylation of JAK2/STAT3 signalling molecules and the decrease in MCL-1 contributed to the anti-tumour efficacy of AA. Collectively, our results suggest that AA could evoke mitochondrial- induced apoptosis in human OS cells by suppression of the JAK2/STAT3 pathway and MCL-1 expression. These results strongly demonstrate that AA could be a potential anti-tumour agent for OS treatment.

Observation of the Doubly Cabibbo-Suppressed Decay D^{+}→K^{+}π^{+}π^{-}π^{0} and Evidence for D^{+}→K^{+}ω

Using 2.93  fb^{-1} of e^{+}e^{-} collision data collected at a center-of-mass energy of 3.773 GeV with the BESIII detector, the first observation of the doubly Cabibbo-suppressed decay D^{+}→K^{+}π^{+}π^{-}π^{0} is reported. After removing decays that contain narrow intermediate resonances, including D^{+}→K^{+}η, D^{+}→K^{+}ω, and D^{+}→K^{+}ϕ, the branching fraction of the decay D^{+}→K^{+}π^{+}π^{-}π^{0} is measured to be (1.13±0.08_{stat}±0.03_{syst})×10^{-3}. The ratio of branching fractions of D^{+}→K^{+}π^{+}π^{-}π^{0} over D^{+}→K^{-}π^{+}π^{+}π^{0} is found to be (1.81±0.15)%, which corresponds to (6.28±0.52)tan^{4}θ_{C}, where θ_{C} is the Cabibbo mixing angle. This ratio is significantly larger than the corresponding ratios for other doubly Cabibbo-suppressed decays. The asymmetry of the branching fractions of charge-conjugated decays D^{±}→K^{±}π^{±}π^{∓}π^{0} is also determined, and no evidence for CP violation is found. In addition, the first evidence for the D^{+}→K^{+}ω decay, with a statistical significance of 3.3σ, is presented and the branching fraction is measured to be B(D^{+}→K^{+}ω)=(5.7_{-2.1}^{+2.5}_{stat}±0.2_{syst})×10^{-5}.

The Mechanical Response and Tolerance of the Anteriorly-Tilted Human Pelvis Under Vertical Loading

Military vehicle underbody blast (UBB) is the cause of many serious injuries in theatre today; however, the effects of these chaotic events on the human body are not well understood. The purpose of this research was to replicate UBB loading conditions on the human pelvis and investigate the resulting response in a controlled laboratory setting. In addition to better understanding the response of the human pelvis to high rate vertical loading, this test series also aimed to identify high rate injury thresholds. Twenty-seven post mortem human surrogate (PMHS) component pelvis tests were completed using the University of Virginia's (UVa) simulated blast rig under a range of loading conditions and postures. Of those tests, 17 were in the anteriorly-tilted posture and used to construct the human injury probability curve. Average seat pan (rigid) accelerations for this subset of tests ranged from 300 to 2400 g over 2 to 3 ms of positive phase duration. Post-test computed tomography (CT) scans and necropsies were performed to determine injuries and revealed a frequent occurrence of anterior and posterior injuries, resulting in unstable pelvis ring fractures. The resulting Human Injury Probability Curve (HIPC) yielded mean forces of 5529, 8516, and 12431 N as measured by mass compensated seat platen loadcells applied through the rigid seat to the bilateral ischium are associated with a 10, 25, and 50% risk for unstable pelvic ring sacrum fractures in an anteriorly-tilted pelvis (28° from vertical), respectively.

Σ^{+} and Σ[over ¯]^{-} Polarization in the J/ψ and ψ(3686) Decays

From 1310.6×10^{6}  J/ψ and 448.1×10^{6}  ψ(3686) events collected with the BESIII experiment, we report the first observation of Σ^{+} and Σ[over ¯]^{-} spin polarization in e^{+}e^{-}→J/ψ[ψ(3686)]→Σ^{+}Σ[over ¯]^{-} decays. The relative phases of the form factors ΔΦ have been measured to be (-15.5±0.7±0.5)° and (21.7±4.0±0.8)° with J/ψ and ψ(3686) data, respectively. The nonzero value of ΔΦ allows for a direct and simultaneous measurement of the decay asymmetry parameters of Σ^{+}→pπ^{0}(α_{0}=-0.998±0.037±0.009) and Σ[over ¯]^{-}→p[over ¯]π^{0}(α[over ¯]_{0}=0.990±0.037±0.011), the latter value being determined for the first time. The average decay asymmetry, (α_{0}-α[over ¯]_{0})/2, is calculated to be -0.994±0.004±0.002. The CP asymmetry A_{CP,Σ}=(α_{0}+α[over ¯]_{0})/(α_{0}-α[over ¯]_{0})=-0.004±0.037±0.010 is extracted for the first time, and is found to be consistent with CP conservation.

[Effect and underling mechanism of 6% hydroxyethyl starch 130/0.4 on serum albumen in trauma orthopedic patients during operation]

Objective: To investigate the effect of 6% hydroxyethyl starch 130/0.4(HES) on protein in severe trauma orthopedic patients after acute hemodilution. Methods: Fourty-eight severe trauma patients who met the inclusion criteria were selected from June 2018 to December 2018 in Yantaishan Hospital, and were randomly divided into two groups (n=24): group A and group B. Group A was ringer's sodium lactate control group, and group B was HES treatment group. After the tracheal intubation, the patients of group A were infused with 10% blood volume of sodium lactate ringer at 0.5 ml·kg(-1)·min(-1), and the patients in group B were infused with 10% blood volume of HES at 0.5 ml·kg(-1)·min(-1). Total protein (TP), human serum albumin (HSA), numbers of circulating endothelium cells (CEC), C-reactive protein (CRP), and serum levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-10 and IL-6 were measured immediately after acute hemodilution (T(0)), 24 hours (T(1)) and 48 hours (T(2)) after acute hemodilution. After infusion into human body, HES bond to HSA, and fluorescence spectroscopy was used to analyze the binding relationship between HES and HSA in order to further study the effects of HES on HSA. Results: The HSA, TP, CEC, TNF-α, IL-6, IL-10, CRP at T(0) of group A were (38±5) g/L, (66±5) g/L, (5.5±0.4)/0.9 μl, (24±5) μg/L, (8.9±0.8) μg/L, (44±6) μg/L, (13.6±1.4) mg/L; While at T(1) were (33±5) g/L, (60±6) g/L, (10.2±0.7)/0.9 μl, (87±9) μg/L, (38.8±2.3) μg/L, (57±7) μg/L, (23.4±2.4) mg/L. The HSA, TP, CEC, TNF-α, IL-6, IL-10, CRP at T(0) of group B were(38±4)g/L, (66±5) g/L, (5.4±0.6)/0.9 μl, (24±6) μg/L, (9.1±0.9) μg/L, (45±6) μg/L, (13.4±1.8) mg/L; While at T(1) were (35±5)g/L, (62±5)g/L, (7.4±0.6)/0.9 μl, (70±8) μg/L, (29.5±3.1) μg/L, (72±6) μg/L, (19.7±2.2) mg/L. HSA and TP decreased at T(1) in group A as compared with T(0) (P<0.05), contrarily CEC increased significantly at T(1), TNF-ɑ, IL-6, IL-10 and CRP augmented at T(1) and T(2) in two groups (P<0.05). In comparison with the patients of group A, CEC decreased significantly at T(1) (P<0.05). TNF-ɑ, IL-6, CRP reduced significantly at T(1) and T(2) (P<0.05), but IL-10 increased at T(1) and T(2) in group B (P<0.05). The secondary structure of HSA changed after HES was added in the HES solution. The fluorescence intensity of HSA decreased with the increase of HES concentration,which suggested that HES induced HSA fluorescence quenching. HES could bind to Trp-214 residue in HSA at a molecular ration of 1∶1. Conclusions: 6% HES reduces the occurrence of low protein level in severe trauma patients after operation. HES could bind to Trp-214 amino acid residue in HSA and form the complex at a molecular ratio of 1∶1. The formation of HES-HSA complex increases the volume of HES, avoids the vascular leakage, protects the vascular endothelial cells, and induces anti-inflammatory immunity in the patients with capillary syndrome.

Study of Open-Charm Decays and Radiative Transitions of the X(3872)

The processes X(3872)→D^{*0}D[over ¯]^{0}+c.c.,γJ/ψ,γψ(2S), and γD^{+}D^{-} are searched for in a 9.0  fb^{-1} data sample collected at center-of-mass energies between 4.178 and 4.278 GeV with the BESIII detector. We observe X(3872)→D^{*0}D^{0}[over ¯]+c.c. and find evidence for X(3872)→γJ/ψ with statistical significances of 7.4σ and 3.5σ, respectively. No evident signals for X(3872)→γψ(2S) and γD^{+}D^{-} are found, and the upper limit on the relative branching ratio R_{γψ}≡{B[X(3872)→γψ(2S)]}/{B[X(3872)→γJ/ψ]}<0.59 is set at 90% confidence level. Measurements of branching ratios relative to decay X(3872)→π^{+}π^{-}J/ψ are also reported for decays X(3872)→D^{*0}D^{0}[over ¯]+c.c.,γψ(2S),γJ/ψ, and γD^{+}D^{-}, as well as the non-D^{*0}D^{0}[over ¯] three-body decays π^{0}D^{0}D^{0}[over ¯] and γD^{0}D^{0}[over ¯].

Measurements of Absolute Branching Fractions of Fourteen Exclusive Hadronic D Decays to η

Using 2.93  fb^{-1} of e^{+}e^{-} collision data taken at a center-of-mass energy of 3.773 GeV with the BESIII detector, we report the first measurements of the absolute branching fractions of 14 hadronic D^{0(+)} decays to exclusive final states with an η, e.g., D^{0}→K^{-}π^{+}η, K_{S}^{0}π^{0}η, K^{+}K^{-}η, K_{S}^{0}K_{S}^{0}η, K^{-}π^{+}π^{0}η, K_{S}^{0}π^{+}π^{-}η, K_{S}^{0}π^{0}π^{0}η, and π^{+}π^{-}π^{0}η; D^{+}→K_{S}^{0}π^{+}η, K_{S}^{0}K^{+}η, K^{-}π^{+}π^{+}η, K_{S}^{0}π^{+}π^{0}η, π^{+}π^{+}π^{-}η, and π^{+}π^{0}π^{0}η. Among these decays, the D^{0}→K^{-}π^{+}η and D^{+}→K_{S}^{0}π^{+}η decays have the largest branching fractions, which are B(D^{0}→K^{-}π^{+}η)=(1.853±0.025_{stat}±0.031_{syst})% and B(D^{+}→K_{S}^{0}π^{+}η)=(1.309±0.037_{stat}±0.031_{syst})%, respectively. The charge-parity asymmetries for the six decays with highest event yields are determined, and no statistically significant charge-parity violation is found.

Determination of Strong-Phase Parameters in D→K_{S,L}^{0}π^{+}π^{-}

We report the most precise measurements to date of the strong-phase parameters between D^{0} and D[over ¯]^{0} decays to K_{S,L}^{0}π^{+}π^{-} using a sample of 2.93  fb^{-1} of e^{+}e^{-} annihilation data collected at a center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider. Our results provide the key inputs for a binned model-independent determination of the Cabibbo-Kobayashi-Maskawa angle γ/ϕ_{3} with B decays. Using our results, the decay model sensitivity to the γ/ϕ_{3} measurement is expected to be between 0.7° and 1.2°, approximately a factor of three smaller than that achievable with previous measurements, based on the studies of the simulated data. The improved precision of this work ensures that measurements of γ/ϕ_{3} will not be limited by knowledge of strong phases for the next decade. Furthermore, our results provide critical input for other flavor-physics investigations, including charm mixing, other measurements of CP violation, and the measurement of strong-phase parameters for other D-decay modes.

First Observation of D^{+}→ημ^{+}ν_{μ} and Measurement of Its Decay Dynamics

By analyzing a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} collected at a center-of-mass energy of 3.773 GeV with the BESIII detector, we measure for the first time the absolute branching fraction of the D^{+}→ημ^{+}ν_{μ} decay to be B_{D^{+}→ημ^{+}ν_{μ}}=(10.4±1.0_{stat}±0.5_{syst})×10^{-4}. Using the world averaged value of B_{D^{+}→ηe^{+}ν_{e}}, the ratio of the two branching fractions is determined to be B_{D^{+}→ημ^{+}ν_{μ}}/B_{D^{+}→ηe^{+}ν_{e}}=0.91±0.13_{(stat+syst)}, which agrees with the theoretical expectation of lepton flavor universality within uncertainty. By studying the differential decay rates in five four-momentum transfer intervals, we obtain the product of the hadronic form factor f_{+}^{η}(0) and the c→d Cabibbo-Kobayashi-Maskawa matrix element |V_{cd}| to be f_{+}^{η}(0)|V_{cd}|=0.087±0.008_{stat}±0.002_{syst}. Taking the input of |V_{cd}| from the global fit in the standard model, we determine f_{+}^{η}(0)=0.39±0.04_{stat}±0.01_{syst}. On the other hand, using the value of f_{+}^{η}(0) calculated in theory, we find |V_{cd}|=0.242±0.022_{stat}±0.006_{syst}±0.033_{theory}.