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OBJECTIVE: This study aimed to quantitatively analyze the calculi components of upper urinary tract calculi and to explore the relationship between calculus components, demographic characteristics, and underlying diseases. PATIENTS AND METHODS: Clinical data of 1,495 patients with upper urinary tract calculi were retrospectively collected. The calculi were divided into simple calcium oxalate, calcium oxalate mixed, calcium phosphate mixed, uric acid, magnesium ammonium phosphate, and other components. Statistical software SPSS 22.0 was used to analyze the differences between the stone compositions and various factors. The influencing factors (p < 0.05) were analyzed using multiple logistic regression analysis. RESULTS: Among 1,495 patients with upper urinary tract calculi, simple calcium oxalate calculi were the most common component (39.7%), followed by calcium oxalate mixed calculi (30.4%), uric acid calculi (13.6%), calcium phosphate mixed calculi (10.4%), magnesium ammonium phosphate calculi (5.8%) and other component calculi (0.1%). Univariate analysis revealed statistically significant differences in stone composition according to gender, age, and hyperuricemia (p < 0.05). Multiple logistic regression analysis showed that compared to men, the odds ratio (OR) values of calcium oxalate mixed stones, calcium phosphate mixed stones, and magnesium ammonium phosphate stones in women were 1.61, 2.50, and 4.17, respectively (p < 0.001). Compared with elderly patients, the OR values of calcium phosphate mixed stones in young and middle-aged patients were 3.14 and 2.70, respectively (p < 0.05). CONCLUSIONS: Patients with different stone components had different demographic characteristics, and stone components were significantly different between gender and age. Calcium oxalate mixed stones were more common in females, and calcium phosphate mixed stones and magnesium ammonium phosphate stones were more common in females, young patients, and middle-aged patients. [ABSTRACT FROM AUTHOR]

The angular distributions of 12C + 90,92,94,96Zr elastic scattering were measured with the Q3D magnetic spectrometer at the HI-13 tandem accelerator, Beijing. The real part of optical potential were extracted by analysing these angular distributions. The analysis enable us to avoid the influence of Coulomb effect and to observe the dependence of optical potential on the nuclear properties. With the deduced potential parameters, the experimental elastic scattering angular distributions can be reproduced very well. Formulas to infer global heavy-ion potential parameters were obtained then by analyzing the extracted optical potential parameters. The formulas can be used widely in heavy-ion nuclear reactions.

In order to investigate the possible influence of metallic environment on the alpha decay process, we have measured the Sm activities in the hosts of metal samarium and SmO . The Sm half-life was found to be (1.06±0.01)×10 y in metal samarium and (1.07±0.01)×10 y in SmO , respectively. No significant change has been observed within the experimental uncertainty. The absolute half-life presented here is consistent with the recommended value. [ABSTRACT FROM AUTHOR]

The angular distribution of the 2H ( 6He,7Li n reaction was measured with a secondary 6He beam of 36.4MeV for the first time. The proton spectroscopic factor of 7Li ground state was extracted to be 0.42±0.06 by normalizing the calculational differential cross-sections with the distorted-wave Born approximation to the experimental data. It was discussed that the uncertainty of extracted spectroscopic factors from the one-nucleon transfer reactions induced by deuteron might be reduced by determining the volume integrals of imaginary optical potentials precisely. [ABSTRACT FROM AUTHOR]

Electronic structures of single crystalline black phosphorus were studied by state-of-the-art angle-resolved photoemission spectroscopy (ARPES). Through high resolution photon energy dependence measurements, the band dispersions along out-of-plane and in-plane directions are experimentally determined. The electrons were found to be more localized in the ab plane than is predicted in calculations. Beside the kz-dispersive bulk bands, a surface resonant state is also observed in the momentum space. Our results strongly suggest that more details need to be considered to fully understand the electronic properties of black phosphorus theoretically. [ABSTRACT FROM AUTHOR]

The proton decay of53Com(3174.1 keV, 19/2-) was investigated via the fragmentation of a 58Ni primary beam. The proton-decay energy was determined with an improved precision to be 1558(8) keV. With this new result and the mass of 53Com, the 52Fe mass excess was derived to be - 48330(8)keV, which is in good agreement with the AMEI2 value. A new recommended value of - 48331.6(49) keV is given. [ABSTRACT FROM AUTHOR]

The angular distributions of the 12C(11B,11B)12C and 12C(11B,12C)11B reactions have been measured at an incident energy of 50 MeV by using the high resolution Q3D magnetic spectrometer of the HI-13 tandem accelerator at China Institute of Atomic Energy, Beijing. The optical potential parameters of the 11B + 12C system are determined by fitting the angular distribution of the elastic scattering and then used to predict the cross sections of the elastic transfer reaction leading to the ground state in l 2C based on distorted-wave Born approximation (DWBA) analysis. Taking into account the interference between the elastic scattering and the elastic transfer processes, the proton spectroscopic factor of the, 12C ground state is extracted to be 2.15 ± 0.23 by constraining the geometrical parameters r0 and a using the rms radius of the valence proton in the 12C ground state. [ABSTRACT FROM AUTHOR]

All the 16F levels are unbound by proton emission. To date the four low-lying 16F levels below 1 MeV have been experimentally identified with well established spin-parity values and excitation energies with an accuracy of 4 - 6 keV. However, there are still considerable discrepancies in their level widths. The present work aims to explore these level widths through an independent method. The angular distributions of the 15N(7Li,6Li)16N reaction leading to the first four states in 16N were measured using a high-precision Q3D magnetic spectrograph. The neutron spectroscopic factors and the asymptotic normalization coefficients for these states in 16N were then derived based on distorted wave Born approximation analysis. The proton widths of the four low-lying resonant states in 16F were obtained according to charge symmetry of strong interaction. [ABSTRACT FROM AUTHOR]

Background: Fluorine is a key element for nucleosynthetic studies since it is extremely sensitive to the physical conditions within stars. The astrophysical site to produce fluorine is suggested to be asymptotic giant branch stars. In these stars the 15N(n,γ)16N reaction could affect the abundance of fluorine by competing with 15N(α,γ)F19. Purpose: The 15N(n,γ)16N reaction rate depends directly on the neutron spectroscopic factors of the low-lying states in 16N. Shell model calculations and two previous measurements of the (d,p) reaction yielded the spectroscopic factors with a discrepancy by a factor of ~2. The present work aims to explore these neutron spectroscopic factors through an independent transfer reaction and to determine the stellar rate of the 15N(n,γ)16N reaction. Methods: The angular distributions of the 15N(Li7,Li6)16N reaction populating the ground state and the first three excited states in 16N are measured using a Q3D magnetic spectrograph and are used to derive the spectroscopic factors of these states based on distorted wave Born approximation analysis. Results: The spectroscopic factors of these four states are extracted to be 0.96 ± 0.09, 0.69 ± 0.09, 0.84 ± 0.08, and 0.65 ± 0.08, respectively. Based on the new spectroscopic factors we derive the 15N(n,γ)16N reaction rate. Conclusions: The accuracy and precision of the spectroscopic factors are enhanced due to the first application of high-precision magnetic spectrograph for resolving the closely spaced 16N levels which cannot be achieved in most recent measurements. The present result demonstrates that two levels corresponding to neutron transfers to the 2s1/2 orbit in 16N are not good single-particle levels although 15N is a closed neutron-shell nucleus. This finding is contrary to the shell model expectation. The present work also provides an independent examination to shed some light on the existing discrepancies in the spectroscopic factors and the 15N(n,γ)16N rate. [ABSTRACT FROM AUTHOR]

The 13C(9Be,8Li)14N angular distribution was measured with a 9Be beam of 40 MeV. The proton spectroscopic factor of the 9Be ground state was extracted to be 0.73 ± 0.15 by the normalization of the calculated differential cross sections with the distorted-wave Born approximation (DWBA) to the experimental data. The spectroscopic factor was compared to existing theoretical and experimental values. [ABSTRACT FROM AUTHOR]

The evolution of massive stars with very low-metallicities depends critically on the amount of CNO nuclides which they produce. The 12N(p, γ)130 reaction is an important branching point in the rap processes, which are believed to be alternative paths to the slow 3a process for producing CNO seed nuclei and thus could change the fate of massive stars. In the present work, the angular distribution of the 2H(12N, 130)n proton transfer reaction at Ec.m. = 8.4 MeV has been measured for the first time. Based on the Johnson-Soper approach, the square of the asymptotic normalization coefficient (ANC) for the virtual decay of 13Og s. --> 12N 4- p was extracted to be 3.92 ± 1.47 fm-' from the measured angular distribution and utilized to compute the direct component in the 12N(p, γ)130 reaction. The direct astrophysical S factor at zero energy was then found to be 0.39 ±0.15 keV b. By considering the direct capture into the ground state of 130, the resonant capture via the first excited state of 130 and their interference, we determined the total astrophysical S factors and rates of the 12N(p, γ130 reaction. The new rate is two orders of magnitude slower than that from the REACLIB compilation. Our reaction network calculations with the present rate imply that 12N(p, γ)130 will only compete successfully with the ß+ decay of 12N at higher (~2 orders of magnitude) densities than initially predicted. [ABSTRACT FROM AUTHOR]

The reaction sequence of 3He(α,γ)7Be(α,γ)11C(p,γ)12N to CNO could be an alterative way of 3α →12C to convert 3He into CNO. It may become important in some specific environments, such as in a very massive star with low metallicity. Whether it is significant depends on the reactions involved, one of the important reactions is the 11C p-capture competing with its β + decay. The S factor for the 11C(p,γ)12N direct capture was obtained in our previous work. This work is to update the reaction rate by adding uncertainty and fitting with the Thielemann format. With the new rate, nucleosynthesis simulations are performed to study the bridge of the p-p chains to CNO through the above sequence. [Copyright &y& Elsevier]

The relative γ-decay probability ratios of the neutron resonance states in 94Zr and 92Zr populated via two-neutron transfer reactions, 92Zr(18O,16O)94Zr and 90Zr(18O,16O)92Zr, have been measured to test the validity of the surrogate ratio method (SRM) in determining the (n, γ) reaction cross section. The cross sections of the 93Zr(n,γ)94Zr reaction are derived from the experimentally obtained ratios and the cross sections of the 91Zr(n,γ)92Zr reaction in the equivalent neutron energy range of En=0-8MeV. The deduced cross sections of 93Zr(n,γ)94Zr reaction agree with the directly measured ones in the low-energy region, and with the evaluated ENDF/B-VII.1 data at higher energies of En>3MeV. The agreement supports the concept of the SRM method to indirectly determine the (n,γ) reaction cross sections. [ABSTRACT FROM AUTHOR]

Objective: To analyze the ultrasonic manifestations, clinical features, high risk factors and key points of pregnancy management in prenatal diagnosis of umbilical artery thrombosis (UAT). Methods: The data of 31 pregnant women of UAT diagnosed by prenatal ultrasonography and confirmed after birth from July 2017 to July 2022 at the Women's Hospital, Zhejiang University School of Medicine were retrospectively analyzed, including the maternal characteristics, pregnancy outcomes and fetal complications. In addition, the baseline data and pregnancy outcomes were compared in 21 patients who continued pregnancy after diagnosis of UAT. Of the 21 UAT cases that continued pregnancy, 10 cases were treated with low molecular weight heparin (LMWH; LMWH treatment group), while the other 11 patients had expectant treatment(expectant treatment group). Results: The age of the 31 pregnant women was (30.2±4.7) years, of which 5 cases (16%,5/31) were advanced age pregnant women. The gestational age at diagnosis was (32.9±4.0) weeks, and the gestational age at termination of pregnancy was (35.6±2.9) weeks. In 31 fetuses with UAT, 15 cases (48%) had fetal distress, 11 cases (35%) had fetal growth restriction, and 3 cases (10%) had intrauterine stillbirth. There were 28 cases of live births, including 26 cases by cesarean section and 2 cases by vaginal delivery. There were also 3 stillbirths, all delivered vaginally. Four neonates had mild asphyxia and two newborns had severe asphyxia. Among the 31 cases, 10 cases were terminated immediately after diagnosis, the gestational age at diagnosis was (35.9±2.9) weeks. Another 21 pregnancies continued, and their gestational age at diagnosis was (31.4±3.7) weeks. The median prolonged gestational age in LMWH treatment group was 7.9 weeks (4.6-9.4 weeks), and all were live births. The median prolonged gestational age in the expectant treatment group was 0.6 weeks (0.0-1.0 weeks), and 2 cases were stillbirths. There was a statistically significant difference in prolonged gestational age ( P =0.002). Conclusions: Ultrasound is the preferred method for prenatal detection of UAT. Clinicians need to be vigilant for UAT when a newly identified single umbilical artery is detected by ultrasound in the second or third trimesters. The decision to continue or terminate the pregnancy depends on the gestational age and the condition of fetus. Attention should be paid to fetal movements as the pregnancy continues. The treatment of LMWH as soon as possible after diagnosis of UAT may improve the pregnancy outcome.

Objective: To investigate the effect of apoptosis-associated protein kinase-like 1 (DAPL1) hypomethylation on prognosis of lung cancer patients with epidermal growth factor receptor gene exon 19 deletion (EGFR Del19) mutation. Methods: The clinicopathological data of lung cancer patients in databases of genomic data sharing (GDC) TCGA lung adenocarcinoma, TCGA lung adenocarcinoma, and TCGA lung cancer were collected to analyze the effect of DAPL1 methylation level on the prognosis of patients with EGFR Del19 mutation. Linear regression model was used for correlation analysis, Kaplan-Meier method was used to draw the survival curve, and the difference of survival curve between the two groups was tested by Log rank. Results: In GDC TCGA lung adenocarcinoma, TCGA lung adenocarcinoma and TCGA lung cancer databases, the 5-year survival rates of lung cancer patients with high DAPL1 expression (31.9%, 27.5% and 33.0%, respectively) were higher than those with low DAPL1 expression (11.0%, 11.6% and 13.8%, respectively). The differences were statistically significant ( P =0.006, 0.028 and 0.025, respectively). The median expression levels of DAPL1 in patients with EGFR Del19 mutation (12.8, 2.75 and 2.9, respectively) were higher than those in patients with other EGFR mutations (11.6, 1.75 and 1.8, respectively, P <0.05). In TCGA lung adenocarcinoma and TCGA lung cancer database, the 5-year survival rate of lung cancer patients with lower DAPL1 methylation levels (22.4% and 16.4%, respectively) were higher than those of lung cancer patients with higher DAPL1 methylation levels (15.1% and 14.2%, respectively), with statistical significance ( P <0.05). The expression level of DAPL1 was positively correlated with the EGFR mutant subtype ( r =0.909, P <0.05), and negatively correlated with DNA methylation ( r =-0.891, P <0.05). The expression of DAPL1 in lung cancer patients was regulated by DNA methylation, which affected the prognosis of lung cancer patients. Conclusion: High DAPL1 expression, or hypomethylation, is associated with lung cancer EGFR Del19 mutation subtype, and DAPL1 hypomethylated lung cancer patients have longer overall survival.

Measurements of food consumption of randomly selected families and fluorine levels in food and beverages were used to calculate the fluorine intake of Tibetan people living in nomadic or semi-nomadic areas of the region and regularly consuming brick tea both as a beverage and in food. The fluorine intake of these groups (children 5.49-7.62 mg day; adults 10.43-14.48 mg/day) was much higher than that of members of a Han population living in the region (children 1.44 mg/day; adults 2.54 mg/day). The amounts of fluorine consumed by the Tibetan inhabitants are at least twice the WHO suggested limit (2 mg/day). Tea plants are rich in fluorine, and the highest levels are found in older leaves which are used to make brick tea. We conclude that brick tea is the major source of fluorine intake by the Tibetan population studied.