Flotation separation of molybdenite and talc using tragacanth gum as depressant and potassium butyl xanthate as collector

Tragacanth gum(TG)was explored as a depressant to realize the flotation separation of molybdenite and talc.The flotation experiments indicated that when using potassium butyl xanthate(PBX)as a collector,molybdenite showed excellent floatability while talc was completely depressed by TG,thus realizing the flotation separation of the two minerals.X-ray photoelectron spectroscopy(XPS)analysis results showed that TG was adsorbed on molybdenite surface via chemisorption.The results of contact angle measurement,Fourier transform infrared(FTIR)spectroscopy,and time-of-flight secondary ion mass spectrometry(ToF-SIMS)indicated that the pre-adsorption of TG on molybdenite could not hinder the further chemisorption of PBX on molybdenite.Because PBX has no collecting ability on talc,the flotation separation of molybdenite and talc came true using PBX to collect molybdenite and TG to depress talc.

Infant cholestasis patient with a novel missense mutation in the AKR1D1 gene successfully treated by early adequate supplementation with chenodeoxycholic acid: A case report and review of the literature

Steroid 5β-reductase [aldo-keto reductase family 1 member D1(AKR1D1)] is essential for bile acid biosynthesis. Bile acid deficiency caused by genetic defects in AKR1D1 leads to life-threatening neonatal hepatitis and cholestasis. There is still limited experience regarding the treatment of this disease. We describe an infant who presented with hyperbilirubinemia and coagulopathy but normal bile acid and γ-glutamyltransferase. Gene analysis was performed using genomic DNA from peripheral lymphocytes from the patient, his parents, and his elder brother. The patient was compound heterozygous for c.919C>T in exon 8 and exhibited a loss of heterozygosity of the AKR1D1 gene, which led to an amino acid substitution of arginine by cysteine at amino acid position 307(p.R307C). Based on these mutations, the patient was confirmed to have primary 5β-reductase deficiency. Ursodeoxycholic acid(UDCA) treatment did not have any effect on the patient. However, when we changed to chenodeoxycholic acid(CDCA) treatment, his symptoms and laboratory tests gradually improved. It is therefore crucial to supplement with an adequate dose of CDCA early to improve clinical symptoms and to normalize laboratory tests.

Current carrying states in the disordered quantum anomalous Hall effect

In a quantum Hall effect,flat Landau levels may be broadened by disorder.However,it has been found that in the thermodynamic limit,all extended(or current carrying)states shrink to one single energy value within each Landau level.On the other hand,a quantum anomalous Hall effect consists of dispersive bands with finite widths.We numerically investigate the picture of current carrying states in this case.With size scaling,the spectrum width of these states in each bulk band still shrinks to a single energy value in the thermodynamic limit,in a power law way.The magnitude of the scaling exponent at the intermediate disorder is close to that in the quantum Hall effects.The number of current carrying states obeys similar scaling rules,so that the density of states of current carrying states is finite.Other states in the bulk band are localized and may contribute to the formation of a topological Anderson insulator.

Spin-down and emission variations for PSR J0742-2822

PSR J0742-2822 is known for its quasi-periodic changes in the observed pulse profile and spindown rate.In this paper,we analyzed 13 years of timing data obtained with the Nanshan 25-m radio telescope and the Parkes 64-m radio telescope.We found that the average values of the spin-down rate((v))of this pulsar changed in four different states.We investigated the correlation between v and W50,and ascertained that the correlation changed in different states.Moreover,not all the changes in states and correlation can be associated with glitch activities.We examined the long term evolution ofγ-ray flux(0.1-300 GeV)and the pulse profiles corresponding to the four different states using Fermi-LAT Pass8(P8 R3)data from 2008 August 5 to 2019 October 1.We did not detect a significant change inγ-ray flux or the pulse profile.Our results suggest that the connection between pulsar rotation and emission is more complex than previously reported for this pulsar.

Size-controllable synthesis and high-performance formic acid oxidation of polycrystalline Pd nanoparticles

A facile approach was developed for the synthesis of polycrystalline palladium nanoparticles(Pd NPs)by using tannic acid(TA) as green reagent and stabilizer in a 30 ℃ water bath. The size of Pd NPs can be tuned in a range of 10–60 nm simply by adjusting the concentration of Pd precursor. The catalytic activity and stability of the as-obtained Pd NPs toward formic acid oxidation were analyzed. It is found that these Pd NPs with different sizes exhibit size-dependent and enhanced formic acid oxidation performance compared to the commercial Pd black catalyst. It should be noted that the Pd catalysts with an average size of 24 nm demonstrate the best catalytic activity and stability among the other prepared Pd NPs, which can be ascribed to its larger electrochemical surface area(ECSA)and polycrystalline structure with defects.

Long interpregnancy interval and adverse perinatal outcomes: a retrospective cohort study

We conducted a retrospective cohort study of 9,552 women experiencing their second delivery between 2014 and 2016 at the International Peace Maternity and Child Health Hospital to investigate the association between the interpregnancy interval(IPI)and adverse perinatal outcomes. With the 12–23-mon IPI as the reference category, logistic regression analyzes were used to examine associations between different IPIs(<12, 12–23, 24–59, 60–119, and ≥120 mon) and perinatal outcomes(gestational diabetes mellitus, premature membrane rupture, gestational hypertension, preterm birth, low birth weight, and macrosomia).Compared with the 12–23-mon IPI category, women with longer IPIs had a higher risk of adverse perinatal outcomes, and those with an IPI ≥120 mon had the highest risk of gestational diabetes mellitus and premature membrane rupture(adjusted odds ratio(OR) 1.76, 95% confidence interval(CI) 1.32–2.35 and adjusted OR 2.03, 95% CI 1.53–2.67, respectively). These results indicate that a longer IPI is associated with a higher risk of adverse perinatal outcomes and an IPI of ≥120 mon appears to be independently associated with a higher risk of gestational diabetes mellitus and premature membrane rupture.

The applied research of simultaneous image acquisition of T2-weighted imaging(T2WI)and diffusion-weighted imaging(DWI)in the assessment of patients with prostate cancer

We aimed to evaluate the feasibility of simultaneous image acquisition of multiple instantaneous switchable scan(MISS)for prostate magnetic resonance imaging(MRI)on 3T.Fifty-three patients were scanned with MRI due to suspected prostate cancer.Twenty-eight of them got histological results.First,two readers assessed the structure delineation and image quality based on images of conventional T2-weighted imaging(T2WI)and diffusion-weighted imaging(DWI)(CTD).Second,two readers identified the index lesion together,and then,reader one evaluated the contrast of index lesion on T2WI and signal ratio on apparent diffusion coefficient map.Third,they assigned Prostate Imaging Reporting and Data System(PI-RADS)score in consensus for the index lesion.After 4 weeks,the images of MISS were reviewed by the same readers following the same process.Finally,two readers gave preference for image interpretation,respectively.Kappa coefficient,Wilcoxon signed-rank test,paired-sample t-test,Bland-Altman analysis,and receiver operating characteristic(ROC)analysis were used for statistical analysis.The acquisition time of CTD was 6 min and 10 st while the acquisition time of MISS was 4 min and 30 s.Interobserver agreements for image evaluation were k=0.65 and k=0.80 for CTD and MISS,respectively.MISS-T2WI showed better delineation for seminal vesicles than CTD-T2WI(reader 1:P<0.001,reader 2:P=0.001).The index lesion demonstrated higher contrast in MISS-T2WI(P<0.001).The FI-RADS scores based on CTD and MISS exhibited high ability in predicting clinically significant cancer(area under curve[AUC]=0.828 vs 0.854).Readers preferred to use MISS in 41.5%-47.2%of cases.MISS showed comparable performance to conventional technique with less acquisition time.