Measurement of the Cross Section for e^{+}e^{-}→Ξ^{-}Ξ[over ¯]^{+} and Observation of an Excited Ξ Baryon

Using a total of 11.0  fb^{-1} of e^{+}e^{-} collision data with center-of-mass energies between 4.009 and 4.6 GeV and collected with the BESIII detector at BEPCII, we measure fifteen exclusive cross sections and effective form factors for the process e^{+}e^{-}→Ξ^{-}Ξ[over ¯]^{+} by means of a single baryon-tag method. After performing a fit to the dressed cross section of e^{+}e^{-}→Ξ^{-}Ξ[over ¯]^{+}, no significant ψ(4230) or ψ(4260) resonance is observed in the Ξ^{-}Ξ[over ¯]^{+} final states, and upper limits at the 90% confidence level on Γ_{ee}B for the processes ψ(4230)/ψ(4260)→Ξ^{-}Ξ[over ¯]^{+} are determined. In addition, an excited Ξ baryon at 1820  MeV/c^{2} is observed with a statistical significance of 6.2-6.5σ by including the systematic uncertainty, and the mass and width are measured to be M=(1825.5±4.7±4.7)  MeV/c^{2} and Γ=(17.0±15.0±7.9)  MeV, which confirms the existence of the J^{P}=3/2^{-} state Ξ(1820).

Observation of the Semileptonic D^{+} Decay into the K[over ¯]_{1}(1270)^{0} Axial-Vector Meson

By analyzing a 2.93  fb^{-1} data sample of e^{+}e^{-} collisions, recorded at a center-of-mass energy of 3.773 GeV with the BESIII detector operated at the BEPCII collider, we report the first observation of the semileptonic D^{+} transition into the axial-vector meson D^{+}→K[over ¯]_{1}(1270)^{0}e^{+}ν_{e} with a statistical significance greater than 10σ. Its decay branching fraction is determined to be B[D^{+}→K[over ¯]_{1}(1270)^{0}e^{+}ν_{e}]=(2.30±0.26_{-0.21}^{+0.18}±0.25)×10^{-3}, where the first and second uncertainties are statistical and systematic, respectively, and the third originates from the input branching fraction of K[over ¯]_{1}(1270)^{0}→K^{-}π^{+}π^{0}.

Observation of the Leptonic Decay D^{+}→τ^{+}ν_{τ}

We report the first observation of D^{+}→τ^{+}ν_{τ} with a significance of 5.1σ. We measure B(D^{+}→τ^{+}ν_{τ})=(1.20±0.24_{stat}±0.12_{syst})×10^{-3}. Taking the world average B(D^{+}→μ^{+}ν_{μ})=(3.74±0.17)×10^{-4}, we obtain R_{τ/μ}=Γ(D^{+}→τ^{+}ν_{τ})/Γ(D^{+}→μ^{+}ν_{μ})=3.21±0.64_{stat}±0.43_{syst}., which is consistent with the standard model expectation of lepton flavor universality. Using external inputs, our results give values for the D^{+} decay constant f_{D^{+}} and the Cabibbo-Kobayashi-Maskawa matrix element |V_{cd}| that are consistent with, but less precise than, other determinations.

Improving the wear performance of feldspathic veneering porcelain by ion-exchange strengthening

OBJECTIVES

The present study examined the effects of Na⁺→K⁺ ion-exchange on the wear performance of feldspathic veneering porcelain.

METHODS

Bar and disk specimens were prepared using IPS classic as the feldspathic veneering porcelain. After ion-exchange by immersion of the specimens in melted KNO₃ at two temperatures for different time-periods, the bars were tested for flexural strength and Vickers surface hardness. The disks were paired with zirconia antagonists and tested with a pin-on-disk tribometer with 10 N for 70☓10⁴ wear cycles in artificial saliva. Wear analysis of the porcelain and zirconia was performed using 3D profilometer and analysed with one-way analysis of variance and Tukey's post-hoc pairwise comparison procedures. Worn surfaces were examined with scanning electron microscopy.

RESULTS

The feldspathic veneering porcelain exhibited strong time-dependent wear behaviour, with typical running-in and steady wear stages. Ion-exchange treatments at 380 °C and 440 °C both enhanced the mechanical properties, decreased the wear rates of running-in wear and steady wear. The wear performance of porcelain treated by ion-exchange at lower temperature (380 °C) was improved significantly, especially reducing the wear rate of the running-in stage.

CONCLUSION

A thicker ion-exchange layer with less stress relaxation may be obtained by ion-exchange at lower exchange temperature for a long processing time. Such a protocol improves the wear performance of the porcelain effectively.

CLINICAL SIGNIFICANCE

Restorations with veneering porcelain may fail prematurely due to excessive wear. It important to improve the wear performance of the porcelain. Ion-exchange has the potential to strengthen dental veneering porcelain. Understanding the effect of ion-exchange on the wear performance of porcelain provides insight improving the wear performance of these restorations.

Complete Measurement of the Λ Electromagnetic Form Factors

The exclusive process e^{+}e^{-}→ΛΛ[over ¯], with Λ→pπ^{-} and Λ[over ¯]→p[over ¯]π^{+}, has been studied at sqrt[s]=2.396  GeV for measurement of the timelike Λ electric and magnetic form factors, G_{E} and G_{M}. A data sample, corresponding to an integrated luminosity of 66.9  pb^{-1}, was collected with the BESIII detector for this purpose. A multidimensional analysis with a complete decomposition of the spin structure of the reaction enables a determination of the modulus of the ratio R=|G_{E}/G_{M}| and, for the first time for any baryon, the relative phase ΔΦ=Φ_{E}-Φ_{M}. The resulting values are R=0.96±0.14(stat)±0.02(syst) and ΔΦ=37°±12°(stat)±6°(syst), respectively. These are obtained using the recently established and most precise value of the asymmetry parameter α_{Λ}=0.750±0.010 measured by BESIII. In addition, the cross section is measured with unprecedented precision to be σ=118.7±5.3(stat)±5.1(syst)  pb, which corresponds to an effective form factor of |G|=0.123±0.003(stat)±0.003(syst). The contribution from two-photon exchange is found to be negligible. Our result enables the first complete determination of baryon timelike electromagnetic form factors.

Pharmacogenetics of statins treatment: Efficacy and safety

WHAT IS KNOWN AND OBJECTIVE

Statins are widely used worldwide in the prevention and treatment of coronary atherosclerotic heart disease and ischaemic stroke. However, in clinical application, statins have shown great individual differences in terms of the efficacy and safety, some of which are related to genetic factors. The purpose of this article was to summarize the recent advances about the correlation between gene polymorphisms and the efficacy/safety of statins.

METHODS

We searched the databases including PharmGKB and PubMed (published before June 2019) using the keywords such as 'statin', 'gene polymorphism' and 'SNP' and obtained more than 100 articles. In this review, we described the clinical studies of genetic variants associated with both the efficacy and adverse reactions of statins. We also clarified the importance of taking pharmacogenetic variation into account to improve the clinical application of statins.

RESULTS AND DISCUSSION

The available data were collected and analysed to present the polymorphisms of candidate genes encoding the most promising proteins including SLCO1B1 (encoding uptake transporters); ABCB1, ABCC2, ABCG2 (encoding effluent transporter); APOE, APOA5 (encoding apolipoprotein); genes encoding cytochrome P450 enzyme system; KIF6, HMGCR, LDLR, LPA, PCSK9, COQ2, CETP, etc These genes were proved to be related to the pharmacodynamics and pharmacokinetics of statins, thus affecting the efficacy and safety.

WHAT IS NEW AND CONCLUSION

In this paper, the correlation between gene polymorphisms and the efficacy/safety of statins was summarized. The authors reached a consensus that the variants of the genes encoding uptake and effluent transporters have the most effect on the efficacy/safety of statins. It pointed out that it is desirable to do genetic testing of these transporter genes to reduce the incidence of myopathy or to achieve better outcomes before patients use statins, especially in the regions with high frequency of risk allele.

Study of e^{+}e^{-}→γωJ/ψ and Observation of X(3872)→ωJ/ψ

We study the e^{+}e^{-}→γωJ/ψ process using 11.6  fb^{-1} e^{+}e^{-} annihilation data taken at center-of-mass energies from sqrt[s]=4.008  GeV to 4.600 GeV with the BESIII detector at the BEPCII storage ring. The X(3872) resonance is observed for the first time in the ωJ/ψ system with a significance of more than 5σ. The relative decay ratio of X(3872)→ωJ/ψ and π^{+}π^{-}J/ψ is measured to be R=1.6_{-0.3}^{+0.4}±0.2, where the first uncertainty is statistical and the second systematic (the same hereafter). The sqrt[s]-dependent cross section of e^{+}e^{-}→γX(3872) is also measured and investigated, and it can be described by a single Breit-Wigner resonance, referred to as the Y(4200), with a mass of 4200.6_{-13.3}^{+7.9}±3.0  MeV/c^{2} and a width of 115_{-26}^{+38}±12  MeV. In addition, to describe the ωJ/ψ mass distribution above 3.9  GeV/c^{2}, we need at least one additional Breit-Wigner resonance, labeled as X(3915), in the fit. The mass and width of the X(3915) are determined. The resonant parameters of the X(3915) agree with those of the Y(3940) in B→KωJ/ψ and of the X(3915) in γγ→ωJ/ψ observed by the Belle and BABAR experiments within errors.

Observation of the Decay X(3872)→π^{0}χ_{c1}(1P)

Using a total of 9.0  fb^{-1} of e^{+}e^{-} collision data with center-of-mass energies between 4.15 and 4.30 GeV collected by the BESIII detector, we search for the processes e^{+}e^{-}→γX(3872) with X(3872)→π^{0}χ_{cJ} for J=0, 1, 2. We report the first observation of X(3872)→π^{0}χ_{c1}, a new decay mode of the X(3872), with a statistical significance of more than 5σ for all systematic fit variations. Normalizing to the previously established process e^{+}e^{-}→γX(3872) with X(3872)→π^{+}π^{-}J/ψ, we find B(X(3872)→π^{0}χ_{c1})/B(X(3872)→π^{+}π^{-}J/ψ)=0.88_{-0.27}^{+0.33}±0.10, where the first error is statistical and the second is systematic. We set 90% confidence level upper limits on the corresponding ratios for the decays to π^{0}χ_{c0} and π^{0}χ_{c2} of 19 and 1.1, respectively.

Precision Measurement of the Branching Fractions of η^{'} Decays

Based on a sample of (1310.6±7.0)×10^{6}J/ψ events collected with the BESIII detector, we present measurements of J/ψ and η^{'} absolute branching fractions using the process J/ψ→γη^{'}. By analyzing events where the radiative photon converts into an e^{+}e^{-} pair, the branching fraction for J/ψ→γη^{'} is measured to be (5.27±0.03±0.05)×10^{-3}. The absolute branching fractions of the five dominant decay channels of the η^{'} are then measured for the first time and are determined to be B(η^{'}→γπ^{+}π^{-})=(29.90±0.03±0.55)%, B(η^{'}→ηπ^{+}π^{-})=(41.24±0.08±1.24)%, B(η^{'}→ηπ^{0}π^{0})=(21.36±0.10±0.92)%, B(η^{'}→γω)=(2.489±0.018±0.074)%, and B(η^{'}→γγ)=(2.331±0.012±0.035)%, where the first uncertainties are statistical and the second systematic.

Measurement of the Dynamics of the Decays D_{s}^{+}→η^{(')}e^{+}ν_{e}

Using e^{+}e^{-} annihilation data corresponding to an integrated luminosity of 3.19  fb^{-1} collected at a center-of-mass energy of 4.178 GeV with the BESIII detector, we measure the absolute branching fractions B_{D_{s}^{+}→ηe^{+}ν_{e}}=(2.323±0.063_{stat}±0.063_{syst})% and B_{D_{s}^{+}→η^{'}e^{+}ν_{e}}=(0.824±0.073_{stat}±0.027_{syst})% via a tagged analysis technique, where one D_{s} is fully reconstructed in a hadronic mode. Combining these measurements with previous BESIII measurements of B_{D^{+}→η^{(')}e^{+}ν_{e}}, the η-η^{'} mixing angle in the quark flavor basis is determined to be ϕ_{P}=(40.1±2.1_{stat}±0.7_{syst})°. From the first measurements of the dynamics of D_{s}^{+}→η^{(')}e^{+}ν_{e} decays, the products of the hadronic form factors f_{+}^{η^{(')}}(0) and the Cabibbo-Kobayashi-Maskawa matrix element |V_{cs}| are determined with different form factor parametrizations. For the two-parameter series expansion, the results are f_{+}^{η}(0)|V_{cs}|=0.4455±0.0053_{stat}±0.0044_{syst} and f_{+}^{η^{'}}(0)|V_{cs}|=0.477±0.049_{stat}±0.011_{syst}.

Semiochemical Regulation of the Intraspecific and Interspecific Behavior of Tomicus yunnanensis and Tomicus minor during the Shoot-Feeding Phase

Two pine shoot beetles, Tomicus yunnanensis and Tomicus minor, are the most destructive pests of Pinus yunnanensis in southwestern China. We investigated behavioral responses within and between these two species during the shoot-feeding phase using walking bioassays. We also identified the pheromonal aspects of beetles by static solid phase microextraction (SPME) and hindgut extraction following interactive communication by gas chromatography-mass spectroscopy (GC-MS). Both species were significantly attracted by their own species and the same sex, and attraction was inhibited by exposure to additional beetles or to the hindgut extracts of beetles which had shown interaction. Female and male T. minor and T. yunnanensis hindguts contained 0.19, 0.09, 0.22, and 0.05 ng/individual of (-)-trans-verbenol, respectively; following interaction with additional beetles, this increased to 16.74-292.71 ng/individual in T. minor females. Mean concentration of verbenone detected in the hindguts of female/male individuals of T. minor and T. yunnanensis under natural conditions were 0.16, 0.06, 0.03, and 0.05 ng/individual, respectively, but these correspondingly increased to 5.90, 2.43, 0.06, and 0.19 ng/individual after exposure to additional insects. In T. yunnanensis, the amounts of detectable (-)-trans-verbenol and verbenone extracted from hindguts were lower than those from T. minor. The levels of cis-verbenol and (-)-trans-verbenol most attractive to walking T. yunnanensis and T. minor were 0.1 and 1.0 ng/μl, respectively. Verbenone was not attractive at any of the concentrations tested. The addition of verbenone to cis-verbenol or (-)-trans-verbenol reduced the attraction responses. We conclude that the (-)-trans-verbenol produced by these two pine shoot beetles is attractive at low concentrations and repellant at high concentrations, thereby fostering intraspecific competition. Verbenone is produced to prevent overcrowding via interspecific inhibition, and to expel beetles during shoot-feeding.

Determination of the Pseudoscalar Decay Constant f_{D_{s}^{+}} via D_{s}^{+}→μ^{+}ν_{μ}

Using a 3.19  fb^{-1} data sample collected at an e^{+}e^{-} center-of-mass energy of E_{cm}=4.178  GeV with the BESIII detector, we measure the branching fraction of the leptonic decay D_{s}^{+}→μ^{+}ν_{μ} to be B_{D_{s}^{+}→μ^{+}ν_{μ}}=(5.49±0.16_{stat}±0.15_{syst})×10^{-3}. Combining our branching fraction with the masses of the D_{s}^{+} and μ^{+} and the lifetime of the D_{s}^{+}, we determine f_{D_{s}^{+}}|V_{cs}|=246.2±3.6_{stat}±3.5_{syst}  MeV. Using the c→s quark mixing matrix element |V_{cs}| determined from a global standard model fit, we evaluate the D_{s}^{+} decay constant f_{D_{s}^{+}}=252.9±3.7_{stat}±3.6_{syst}  MeV. Alternatively, using the value of f_{D_{s}^{+}} calculated by lattice quantum chromodynamics, we find |V_{cs}|=0.985±0.014_{stat}±0.014_{syst}. These values of B_{D_{s}^{+}→μ^{+}ν_{μ}}, f_{D_{s}^{+}}|V_{cs}|, f_{D_{s}^{+}} and |V_{cs}| are each the most precise results to date.

First Measurement of the Form Factors in D_{s}^{+}→K^{0}e^{+}ν_{e} and D_{s}^{+}→K^{*0}e^{+}ν_{e} Decays

We report on new measurements of Cabibbo-suppressed semileptonic D_{s}^{+} decays using 3.19  fb^{-1} of e^{+}e^{-} annihilation data sample collected at a center-of-mass energy of 4.178 GeV with the BESIII detector at the BEPCII collider. Our results include branching fractions B(D_{s}^{+}→K^{0}e^{+}ν_{e})=[3.25±0.38(stat)±0.16(syst)]×10^{-3} and B(D_{s}^{+}→K^{*0}e^{+}ν_{e})=[2.37±0.26(stat)±0.20(syst)]×10^{-3}, which are much improved relative to previous measurements, and the first measurements of the hadronic form-factor parameters for these decays. For D_{s}^{+}→K^{0}e^{+}ν_{e}, we obtain f_{+}(0)=0.720±0.084(stat)±0.013(syst), and for D_{s}^{+}→K^{*0}e^{+}ν_{e}, we find form-factor ratios r_{V}=V(0)/A_{1}(0)=1.67±0.34(stat)±0.16(syst) and r_{2}=A_{2}(0)/A_{1}(0)=0.77±0.28(stat)±0.07(syst).

Observation of D^{+}→f_{0}(500)e^{+}ν_{e} and Improved Measurements of D→ρe^{+}ν_{e}

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} recorded by the BESIII detector at a center-of-mass energy of 3.773 GeV, we present an analysis of the decays D^{0}→π^{-}π^{0}e^{+}ν_{e} and D^{+}→π^{-}π^{+}e^{+}ν_{e}. By performing a partial wave analysis, the π^{+}π^{-} S-wave contribution to D^{+}→π^{-}π^{+}e^{+}ν_{e} is observed to be (25.7±1.6±1.1)% with a statistical significance greater than 10σ, besides the dominant P-wave contribution. This is the first observation of the S-wave contribution. We measure the branching fractions B(D^{0}→ρ^{-}e^{+}ν_{e})=(1.445±0.058±0.039)×10^{-3}, B(D^{+}→ρ^{0}e^{+}ν_{e})=(1.860±0.070±0.061)×10^{-3}, and B(D^{+}→f_{0}(500)e^{+}ν_{e},f_{0}(500)→π^{+}π^{-})=(6.30±0.43±0.32)×10^{-4}. An upper limit of B(D^{+}→f_{0}(980)e^{+}ν_{e},f_{0}(980)→π^{+}π^{-})<2.8×10^{-5} is set at the 90% confidence level. We also obtain the hadronic form factor ratios of D→ρe^{+}ν_{e} at q^{2}=0 assuming the single-pole dominance parametrization: r_{V}={[V(0)]/[A_{1}(0)]}=1.695±0.083±0.051, r_{2}={[A_{2}(0)]/[A_{1}(0)]}=0.845±0.056±0.039.

The prevalence of depressive symptoms in 'left-behind children' in China: a meta-analysis of comparative studies and epidemiological surveys

BACKGROUND

Depressive symptoms are common in 'left-behind children (LBC)' in China, but their prevalence estimates have been inconsistent. This comprehensive meta-analysis examined the pooled prevalence of depressive symptoms in LBC in China and its associated factors.

METHODS

Two investigators systematically and independently searched both English (PubMed, PsycINFO, and EMBASE) and Chinese (WanFang Database, CNKI, and SinoMed) databases. Comparative and epidemiological studies reporting the prevalence of depressive symptoms and associated relevant information were included. The prevalence of depressive symptoms was pooled using the random-effects model.

RESULTS

A total of 39 studies covering 31,663 LBC and 20,049 non-LBC controls were included in the meta-analysis. The figures of pooled prevalence of depressive symptoms in LBC and non-LBC were 30.7% and 22.8%, respectively. Subgroup analyses revealed that the use of different scales was significantly associated with the prevalence of depressive symptoms. Compared with non-LBC, LBC were more likely to suffer from depressive symptoms (OR = 1.7, 95% CI: 1.4-1.9).

CONCLUSIONS

This meta-analysis confirmed that the prevalence of depressive symptoms in LBC is common in China. In order to reduce the risk of depressive symptoms in this vulnerable segment of the population, the development of screening and therapeutic interventions is urgently needed.

Study of the D^{0}→K^{-}μ^{+}ν_{μ} Dynamics and Test of Lepton Flavor Universality with D^{0}→K^{-}ℓ^{+}ν_{ℓ} Decays

Using e^{+}e^{-} annihilation data of 2.93  fb^{-1} collected at center-of-mass energy sqrt[s]=3.773  GeV with the BESIII detector, we measure the absolute branching fraction of D^{0}→K^{-}μ^{+}ν_{μ} with significantly improved precision: B_{D^{0}→K^{-}μ^{+}ν_{μ}}=(3.413±0.019_{stat}±0.035_{syst})%. Combining with our previous measurement of B_{D^{0}→K^{-}e^{+}ν_{e}}, the ratio of the two branching fractions is determined to be B_{D^{0}→K^{-}μ^{+}ν_{μ}}/B_{D^{0}→K^{-}e^{+}ν_{e}}=0.974±0.007_{stat}±0.012_{syst}, which agrees with the theoretical expectation of lepton flavor universality within the uncertainty. A study of the ratio of the two branching fractions in different four-momentum transfer regions is also performed, and no evidence for lepton flavor universality violation is found with current statistics. Taking inputs from global fit in the standard model and lattice quantum chromodynamics separately, we determine f_{+}^{K}(0)=0.7327±0.0039_{stat}±0.0030_{syst} and |V_{cs}|=0.955±0.005_{stat}±0.004_{syst}±0.024_{LQCD}.

Observation of the Semileptonic Decay D^{0}→a_{0}(980)^{-}e^{+}ν_{e} and Evidence for D^{+}→a_{0}(980)^{0}e^{+}ν_{e}

Using an e^{+}e^{-} collision data sample of 2.93  fb^{-1} collected at a center-of-mass energy of 3.773 GeV by the BESIII detector at BEPCII, we report the observation of D^{0}→a_{0}(980)^{-}e^{+}ν_{e} and evidence for D^{+}→a_{0}(980)^{0}e^{+}ν_{e} with significances of 6.4σ and 2.9σ, respectively. The absolute branching fractions are determined to be B(D^{0}→a_{0}(980)^{-}e^{+}ν_{e})×B(a_{0}(980)^{-}→ηπ^{-})=[1.33_{-0.29}^{+0.33}(stat)±0.09(syst)]×10^{-4} and B(D^{+}→a_{0}(980)^{0}e^{+}ν_{e})×B(a_{0}(980)^{0}→ηπ^{0})=[1.66_{-0.66}^{+0.81}(stat)±0.11(syst)]×10^{-4}. This is the first time the a_{0}(980) meson has been measured in a D^{0} semileptonic decay, which would open one more interesting page in the investigation of the nature of the puzzling a_{0}(980) states.

[Study on diffusion kurtosis imaging in hyperacute phase of mild traumatic brain injury]

Objective: To explore the changes of cerebral white matter in the hyperacute period (<24 h) patients with mild traumatic brain injury (mTBI) by diffusion kurtosis imaging(DKI) technique. Methods: A total of 52 patients with mTBI were included in this study, collected in Emergency Department of Affiliated Hospital of Hangzhou Normal University from May 2016 to June 2017. Twenty-one healthy controls were recruited at the mean time(gender, age and years of education were matched with the patients). DKI data were acquired with 3.0 T scanners.The FSL software was used to preprocess the DKI data, and the white matter abnormalities were detected by tract-based spatial statistics (TBSS). Results: There were no statistical differences in gender, age and years of education between mTBI patients and healthy controls (P=0.427, P=0.235, P=0.165). The values of MK of the body of corpus callosum (BCC), the genu of corpus callosum (GCC), the splenium of corpus callosum (SCC), the bilateral anterior limb of interbal capsule (ALIP), the right posterior limb of internal capsule (PLIC_R), the bilateral anterior corona radiate (ACR), the bilateral posterior corona radiate (PCR), the bilateral superior corona radiate (SCR), the left inferior fronto-occipital fasciculus (IFOF_L)and the bilateral superior longitudinal fasciculus (SLF) were lower in mTBI patients((1.095±0.080), (1.130±0.066), (1.160±0.080), (1.135±0.077), (1.108±0.076), (1.203±0.069), (1.073±0.056), (1.052±0.055), (1.170±0.055), (1.149±0.050), (1.028±0.056), (1.051±0.059), (0.868±0.060), (1.194±0.048), (1.183±0.054) mm(2)/s) than those in healthy controls((1.153±0.054), (1.184±0.057), (1.215±0.068), (1.181±0.053), (1.163±0.062), (1.258±0.041), (1.115±0.037), (1.096±0.049), (1.210±0.040), (1.190±0.049), (1.063±0.042), (1.087±0.057), (0.913±0.063), (1.236±0.047), (1.214±0.038) mm(2)/s)(P<0.01). However, there were no statistical differences in fractional anisotropy (FA) between groups (P>0.01). Conclusion: DKI technology is more sensitive in detecting cerebral white matter abnormalities in patients with hyperacute mTBI which routine MRI findings was normal.

Molecular cloning and characterization of a gonadotropin-releasing hormone receptor homolog in the Chinese mitten crab, Eriocheir sinensis

As an essential mediator in the Gonadotropin-releasing hormone (GnRH) signaling pathway, GnRH receptor (GnRHR) coupled to GnRH, plays an important role in activating the downstream pathway after stimulating a series of cascades to regulate reproduction. To detect the existence of GnRHR and potential GnRH signaling pathway, we cloned and characterized GnRHR in the Chinese mitten crab, Eriocheir sinensis (named EsGnRHR). The full-length EsGnRHR cDNA is 2038 bp in length, including an open reading frame (ORF) of 1566 bp, a 57 bp 5'-untranslated region (5'-UTR) and a 415 bp 3'-UTR. Prediction of transmembrane domains in protein sequence revealed that the EsGnRHR protein contained seven hydrophobic transmembrane regions (TMs). Reverse transcription PCR revealed that EsGnRHR was mainly expressed in the thoracic nerve group and ovary, and weakly distributed in the testis and brain. In situ hybridization further demonstrated that EsGnRHR mRNA was localized at the protocerebrum and deutocerebrum. In the ovary and testis, the hybridization signal was dominantly at the earlier developmental stages. The signal was mainly localized in the cytoplasm cell in the ovary, and in the epithelium cell in the testis. During the different stages of gonadal development, EsGnRHR displayed increasing trends in both female and male when analyzed by quantitative real-time PCR, suggesting that EsGnRHR was involved in controlling gonadal development. Our study provides important information for further research on the molecular mechanisms underlying crab development.

Time-resolved photoion imaging spectroscopy: Determining energy distribution in multiphoton absorption experiments

We propose an approach to determine the excitation energy distribution due to multiphoton absorption in the case of excited systems following decays to produce different ion species. This approach is based on the measurement of the time-resolved photoion position spectrum by using velocity map imaging spectrometry and an unfocused laser beam with a low fluence and homogeneous profile. Such a measurement allows us to identify the species and the origin of each ion detected and to depict the energy distribution using a pure Poisson's equation involving only one variable which is proportional to the absolute photon absorption cross section. A cascade decay model is used to build direct connections between the energy distribution and the probability to detect each ionic species. Comparison between experiments and simulations permits the energy distribution and accordingly the absolute photon absorption cross section to be determined. This approach is illustrated using C₆₀ as an example. It may therefore be extended to a wide variety of molecules and clusters having decay mechanisms similar to those of fullerene molecules.

KRAS and BRAF mutations in serum exosomes from patients with colorectal cancer in a Chinese population

The efficacy of epidermal growth factor receptor- targeted therapy is significantly associated with Kirsten rat sarcoma viral oncogene homolog (KRAS) and B-raf serine/threonine kinase proto-oncogene (BRAF) mutation in patients with colorectal cancer (CRC), for which the standard gene testing is currently performed using tumor tissue DNA. The aim of the present study was to compare the presence of KRAS and BRAF mutations in the serum exosome and primary tumor tissue from patients with CRC. Genomic DNA were extracted from the tumor tissues of 35 patients with histologically-confirmed CRC and exosomal mRNA were obtained from peripheral blood, which were collected from the corresponding patients prior to surgery. Three mutations in the KRAS gene (codons 12, 13 and 61) and a mutation in the BRAF gene (codon 600) were detected using a polymerase chain reaction-based sequencing method and their presence were compared between tumor tissues and the matched serum exosomes. The KRAS mutation rates in tumor tissues and the matched serum exosomes were 57.6 and 42.4%, respectively, which was not significantly different (P=0.063). The detection rate of the BRAF mutation was 24.2 and 18.2% in tumor tissues and the matched serum exosomes, respectively, and there was no significant difference (P=0.500). The patients with CRC that had a KRAS mutation of codon 12 in exon 2 in their tumor tissues and serum exosomes were significantly older compared with those without this mutation (tumor tissue, P=0.002; serum exosome, P=0.022). The sensitivity of KRAS and BRAF mutation detection using exosomal mRNA was 73.7 and 75%, respectively. The specificity of the detected mutations exhibited an efficiency of 100%, and the total consistency rate was 94.9 and 93.9% for KRAS and BRAF mutations, respectively. These results suggested that serum exosomal mRNA may be used as a novel source for the rapid and non-invasive genotyping of patients with CRC.

Hydrothermal synthesis and structural characterization of metal-organic frameworks based on new tetradentate ligands

The hydrothermal reaction of two new tetradentate ligands with different metal salts of cadmium nitrate, zinc chloride, cobalt nitrate and deprotonated terephthalic acid (H2tp), isophthalic acid (H2ip), 4,4'-oxybisbenzoic acid (H2obba) in H2O/DMF or H2O/methanol gave three metal-organic frameworks (MOFs): {[Zn2(L1)(tp)(formate)2]·H2O}n (), {[Cd2(L2)(ip)2]·2H2O}n (), {[Co2(L2)(obba)2]}n () (L1 = 1,2-bis {2,6-bis [(1H-imidazol-1-yl) methyl]-4-methylphenoxy} ethane, L2 = 1,3-bis {2,6-bis [(1H-imidazol-1-yl) methyl]-4-methylphenoxy} propane). The structures of the frameworks are established by single-crystal X-ray diffraction. Compound is a three-dimensional (3D) framework with a 2-fold interpenetrated form, which exhibits a 2-nodal (3,4)-connected fsh-3,4-P21/c net with a {8(3)}2{8(5)·10} topology. Compound has a 2-nodal (4,8)-connected 3D framework where the dinuclear cadmium cluster secondary building units (SBUs) assemble with isophthalate and ligand L2 to construct a rare topological type sqc22 net with a {3(2)·5(4)}{3(4)·4(4)·5(10)·6(10)} topology. Whereas, Compound can be extended to a 2D interlocked (4,4)-connected 4,4 L28 net with the point symbol {4·6(4)·8}2{4(2)·6(4)}. L1 and L2 are tetradentate ligands with diverse linkers and display different coordination modes. In addition, the thermal stability and photochemical properties of the frameworks are also investigated.