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We report the synthesis and characterization of a Si-based ternary semiconductor Mg$_3$Si$_2$Te$_6$, which exhibits a quasi-two-dimensional structure, where the trigonal Mg$_2$Si$_2$Te$_6$ layers are separated by Mg ions. Ultraviolet-visible absorption spectroscopy and density functional theory calculations were performed to investigate the electronic structure. The experimentally determined direct band gap is 1.39 eV, consistent with the value of the density function theory calculations. Our results reveal that Mg$_3$Si$_2$Te$_6$ is a direct gap semiconductor with a relatively narrow gap, which is a potential candidate for infrared optoelectronic devices., 5 pages, 5 figures

We report the synthesis and characterization of RbNi$_2$Se$_2$, an analog of the iron chalcogenide superconductor Rb$_x$Fe$_2$Se$_2$, via transport, angle resolved photoemission spectroscopy, and density functional theory calculations. A superconducting transition at $T_{c}$ = 1.20 K is identified. In normal state, RbNi$_2$Se$_2$ shows paramagnetic and Fermi liquid behaviors. A large Sommerfeld coefficient yields a heavy effective electron mass of $m^{*}\approx6m_{e}$. In the superconducting state, zero-field electronic specific-heat data $C_{es}$ can be described by a two-gap BCS model, indicating that RbNi$_2$Se$_2$ is a multi-gap superconductor. Our density functional theory calculations and angle resolved photoemission spectroscopy measurements demonstrate that RbNi$_2$Se$_2$ exhibits relatively weak correlations and multi-band characteristics, consistent with the multi-gap superconductivity., 7 pages, 4 figures

We report high pressure studies on the C-type antiferromagnetic semiconductor EuTe2 up to 36.0 GPa. A structural transition from the I4/mcm to C2/m space group is identified at ~16 GPa. Superconductivity is discovered above ~5 GPa in both the I4/mcm and C2/m space groups. In the low-pressure phase (< 16 GPa), the antiferromagnetic transition temperature is enhanced with increasing pressure due to the enhanced magnetic exchange interactions. Magnetoresistance measurements indicate an interplay between the local moments of Eu2+ and the conduction electrons of Te 5p orbits. The upper critical field of the superconductivity is well above the Pauli limit. Across the structural transition to the high-pressure phase (> 16 GPa), EuTe2 becomes nonmagnetic and the superconducting transition temperature evolves smoothly with the upper critical field below the Pauli limit. Therefore, the high upper critical field of EuTe2 in the low-pressure phase is due to the exchange field compensation effect of the Eu magnetic order and the superconductivity in both structures may arise in the framework of the BCS theory., 11 pages,5 figures with 8 pages supplementary

We report a comprehensive high-pressure study, up to 21.1 GPa, on the antiferromagnetic topological insulator EuSn2As2 achieved through synchrotron X-ray diffraction, Raman scattering, electrical resistance, magnetic resistance, and Hall transport measurements in combination with first-principles calculations. The Neel temperatures determined from resistance are increased from (24±1) to (77±8) K under pressure, which is a result of enhanced magnetic exchange couplings between Eu2+ ions yielded by our first-principles calculations. The negative magnetoresistance of EuSn2As2 persists to higher temperatures accordingly. However, the enhancement of the observed Neel temperatures deviates from the calculations above 10.0 GPa. In addition, the magnitude of the magnetoresistance, Hall coefficients, and charge carrier densities show abrupt changes between 6.9 and 10.0 GPa. The abrupt changes likely originate from a pressure-induced valence change of Eu ions from a divalent state to a divalent and trivalent mixed state or are related to the structural transition revealed by Raman scattering measurements. Our results provide insight into magnetism variation in EuSn2As2 and similar antiferromagnetic topological insulators under pressure.

We report experimental studies of a series of BaFe(2)S(3–x)Se(x) (0 ⩽ x ⩽ 3) single crystals and powder specimens using x-ray diffraction, neutron-diffraction, muon-spin-relaxation, and electrical transport measurements. A structural transformation from Cmcm (BaFe(2)S(3)) to Pnma (BaFe(2)Se(3)) was identified around x = 0.7 – 1. Neutron-diffraction measurements on the samples with x = 0.2, 0.4, and 0.7 reveal that the Néel temperature of the stripe antiferromagnetic order is gradually suppressed from ~120 to 85 K, while the magnitude of the ordered Fe(2+) moments shows very little variation. Similarly, the block antiferromagnetic order in BaFe(2)Se(3) remains robust for 1.5 ⩽ x ⩽ 3 with negligible variation in the ordered moment and a slight decrease of the Néel temperature from 250 K (x = 3) to 225 K (x = 1.5). The sample with x = 1 near the Cmcm and Pnma border shows coexisting, two-dimensional, short-range stripe- and block-type antiferromagnetic correlations. The system remains insulating for all x, but the thermal activation gap shows an abrupt increase when traversing the boundary from the Cmcm stripe phase to the Pnma block phase. The results demonstrate that the crystal structure, magnetic order, and electronic properties are strongly coupled in the BaFe(2)S(3–x)Se(x) system.

BackgroundThis meta-analysis of prospective observational studies and randomized controlled trials (RCTs) was carried out to explore the association between selenium and the risk of cardiovascular disease (CVD) and all-cause mortality.Methods and Study DesignWe searched the PubMed, EMBASE and Web of Science database for eligible studies which included the relationship between selenium and the outcomes of interest. 25 prospective observational studies and 9 RCTs were included in our meta-analysis.ResultsThe observational studies showed that there was a significant inverse association between serum selenium and the risk of CVD (RR: 0.78; 95% CI: 0.68–0.89), coronary heart disease (CHD) (RR: 0.75; 95% CI: 0.58–0.95) and all-cause mortality (RR: 0.77; 95% CI: 0.71–0.84). We also found a significant inverse association between selenium supplements and the risk of total CVD (RR: 0.78; 95% CI: 0.62–0.98) and all-cause mortality (RR: 0.81; 95% CI: 0.65-1.00) in RCTs studies.ConclusionsOur meta-analysis found a significant inverse association between selenium and CVD, CHD, and all-cause mortality in prospective observational studies and RCTs, which indicate the selenium has protective effect in cardiovascular disease and all-cause mortality.

Layered structural materials have been a fertile playground to investigate mechanisms of fundamental physics and explore potential applications. Here, we report investigations on ferromagnetic van der Waals $\mathrm{Cr}\mathrm{Si}{\mathrm{Te}}_{3}$ via high-pressure synchrotron x-ray diffraction, electrical resistance, and magnetoresistance measurements. Under compression, $\mathrm{Cr}\mathrm{Si}{\mathrm{Te}}_{3}$ undergoes an insulator-metal transition and a structural transition at $\ensuremath{\sim}7.5$ GPa. Concomitantly with the structural transition, the magnetoresistance changes sign, the negative Hall coefficient increases dramatically, and superconductivity emerges at 3 K. The superconductivity persists up to the highest measured pressure of 47.1 GPa with a maximum ${T}_{c}\ensuremath{\approx}$ 4.5 K at $\ensuremath{\sim}30$ GPa. Our results suggest that $\mathrm{Cr}\mathrm{Si}{\mathrm{Te}}_{3}$ is paramagnetic in the pressure range of superconductivity. The discoveries of superconductivity and magnetic transition in ferromagnetic $\mathrm{Cr}\mathrm{Si}{\mathrm{Te}}_{3}$ under pressure provide new perspectives to explore the interplay between superconductivity and magnetism in Cr-based two-dimensional van der Waals materials.

We report studies of the magnetic properties of a staggered stacked triangular lattice ${\mathrm{Ba}}_{2}\mathrm{Mn}\mathrm{Te}{\mathrm{O}}_{6}$ using magnetic susceptibility, specific heat, neutron powder diffraction, inelastic neutron scattering measurements, and first-principles density functional theory calculations. Neutron diffraction measurements reveal ${\mathrm{Ba}}_{2}\mathrm{Mn}\mathrm{Te}{\mathrm{O}}_{6}$ to be antiferromagnetically ordered with a propagation vector $\mathbit{k}=(0.5,0.5,0)$ and N\'eel transition temperature of ${T}_{\text{N}}\ensuremath{\approx}20$ K. The dominant interaction derived from the Curie-Weiss fitting to the inverse DC susceptibility is antiferromagnetic. Modeling of the inelastic neutron scattering data with linear spin wave theory yielded magnetic exchange interactions for the nearest intralayer, nearest interlayer, and next-nearest interlayer of ${J}_{1}=0.27(3)$, meV ${J}_{2}=0.27(3)$ meV, and ${J}_{3}=\ensuremath{-}0.05(1)$ meV, respectively, and a small value of easy-axis anisotropy of ${D}_{zz}=\ensuremath{-}0.01$ meV. We derive a magnetic phase diagram that reveals a collinear stripe-type antiferromagnetic order that is stabilized by the competition between ${J}_{1},\phantom{\rule{4pt}{0ex}}{J}_{2}$, and ${J}_{3}$.

We report experimental studies of a series of BaFe2S3-x Se x (0 ⩽ x ⩽ 3) single crystals and powder specimens using x-ray diffraction, neutron-diffraction, muon-spin-relaxation, and electrical transport measurements. A structural transformation from Cmcm (BaFe2S3) to Pnma (BaFe2Se3) was identified around x = 0.7 - 1. Neutron-diffraction measurements on the samples with x = 0.2, 0.4, and 0.7 reveal that the Neel temperature of the stripe antiferromagnetic order is gradually suppressed from ~120 to 85 K, while the magnitude of the ordered Fe2+ moments shows very little variation. Similarly, the block antiferromagnetic order in BaFe2Se3 remains robust for 1.5 ⩽ x ⩽ 3 with negligible variation in the ordered moment and a slight decrease of the Neel temperature from 250 K (x = 3) to 225 K (x = 1.5). The sample with x = 1 near the Cmcm and Pnma border shows coexisting, two-dimensional, short-range stripe- and block-type antiferromagnetic correlations. The system remains insulating for all x, but the thermal activation gap shows an abrupt increase when traversing the boundary from the Cmcm stripe phase to the Pnma block phase. The results demonstrate that the crystal structure, magnetic order, and electronic properties are strongly coupled in the BaFe2S3-x Se x system.

We report a comprehensive study of the spin ladder compound ${\mathrm{BaFe}}_{2}{\mathrm{S}}_{2.5}{\mathrm{Se}}_{0.5}$ using neutron diffraction, inelastic neutron scattering, high pressure synchrotron diffraction, and high pressure transport techniques. We find that ${\mathrm{BaFe}}_{2}{\mathrm{S}}_{2.5}{\mathrm{Se}}_{0.5}$ possesses the same $Cmcm$ structure and stripe antiferromagnetic order as does ${\mathrm{BaFe}}_{2}{\mathrm{S}}_{3}$, but with a reduced N\'eel temperature of ${T}_{N}=98$ K compared to 120 K for the undoped system, and a slightly increased ordered moment of $1.40\phantom{\rule{0.16em}{0ex}}{\ensuremath{\mu}}_{B}$ per iron. The low-energy spin excitations in ${\mathrm{BaFe}}_{2}{\mathrm{S}}_{2.5}{\mathrm{Se}}_{0.5}$ are likewise similar to those observed in ${\mathrm{BaFe}}_{2}{\mathrm{S}}_{3}$. However, unlike the reports of superconductivity in ${\mathrm{BaFe}}_{2}{\mathrm{S}}_{3}$ below ${T}_{c}\ensuremath{\sim}14$ K under pressures of 10 GPa or more, we observe no superconductivity in ${\mathrm{BaFe}}_{2}{\mathrm{S}}_{2.5}{\mathrm{Se}}_{0.5}$ at any pressure up to 19.7 GPa. In contrast, the resistivity exhibits an upturn at low temperature under pressure. Furthermore, we show that additional high-quality samples of ${\mathrm{BaFe}}_{2}{\mathrm{S}}_{3}$ synthesized for this study likewise fail to become superconducting under pressure, instead displaying a similar upturn in resistivity at low temperature. These results demonstrate that microscopic, sample-specific details play an important role in determining the ultimate electronic ground state in this spin ladder system. We suggest that the upturn in resistivity at low temperature in both ${\mathrm{BaFe}}_{2}{\mathrm{S}}_{3}$ and ${\mathrm{BaFe}}_{2}{\mathrm{S}}_{2.5}{\mathrm{Se}}_{0.5}$ may result from Anderson localization induced by S vacancies and random Se substitutions, enhanced by the quasi-one-dimensional ladder structure.

Several studies have reported a conflicting association between vitamin D deficiency, vitamin D receptor (VDR) polymorphism, and the risk of cardiovascular disease (CVD). We hypothesized that serum 25(OH)D concentrations and single nucleotide polymorphisms (SNPs) of the VDR were associated with and increased risk of CVD. A total of 2378 adults residing in rural parts of China participated in this study. Ultimately, 1142 individuals, including 638 CVD patients and 504 control subjects were included in the study. Logistic regression and restricted cubic spines regression were used to determine the correlation between 25(OH)D and the risk of CVD. Allele frequency and genotype distribution were analyzed between CVD patients and control subjects, and haplotype analysis was used to evaluate the combined effect of VDR SNPs on CVD pathogenesis. In the adjusted model, the odds ratio (95% confidence interval (CI)) of the CVD in the sufficient vitamin D group was 0.76 (0.60–0.96)when compared with the vitamin D deficient group. At 25(OH)D doses of less than 20 ng/mL, there was a dose–response relationship between 25(OH)D and CVD risk. Moreover, the rs3847987 SNP was associated with fasting plasma glucose (FPG) and triglyceride (TG) in CVD patients. In all models, there was a significant association between rs2189480 and CVD, especially in females and those aged ≥55 years. In these groups, rs3847987 SNPs were significantly different, especially in females. Compared with the ACA haplotype, the AAA and CCA haplotypes were associated with increased risk of CVD. In conclusion, our results suggested that serum 25(OH)D levels and VDR SNPs are closely related with CVD pathogenesis.

Background A low serum vitamin D concentration is associated with an increased risk of type 2 diabetes mellitus (T2DM). Recently, several single nucleotid polymorphisms (SNPs) have been identified which influence vitamin D levels. If a causal relationship exists between vitamin D concentrations and T2DM, one would expect a similar association between the newly identified SNPs and T2DM risk. Therefore, this study investigated the association between four SNPs of cytochrome P450 family 2, subfamily R, peptide 1 (CYP2R1) gene, serum 25(OH)D3 levels and T2DM. Methods Three hundred and ninety-seven patients with confirmed T2DM, as well as 397 age- and gender-matched controls were enrolled in this case-control study. Genotyping was performed by TaqMan probe assays. Kruskal-Wallis one-way analysis and muitiple logistic regression analysis were performed to identify the possible risk genotype for vitamin D levels and T2DM, respectively. Generalized multifactor dimensionality reduction (GMDR) was used to analyze the gene-gene and gene-environment interactions. Results The serum 25(OH)D3 levels were significant lower in the T2DM group. Significant differences were observed between patients and controls in terms of the genotype distributions of rs1993116 (P = 0.048) and rs10766197 (P = 0.024). Similarly, rs1993116 and rs10766197 polymorphisms were found to be significantly associated with T2DM risk. AG + GG genotype carriers of the rs1993116 and rs10766197 polymorphisms could have an increased risk of developing T2DM compared with AA carriers, the OR and 95% CI were 1.64 (1.09–2.46) and 1.76 (1.18–2.65), respectively. However, none of the tested SNPs were independently associated with serum 25(OH)D3 levels (P > 0.059). Gene-gene and gene-environment interaction analyses indicated that rs12794714-rs10766197 and rs12794714-vitamin D deficiency (VDD) models successfully predicted T2DM risk (P Conclusions Rs1993116 and rs10766197 polymorphisms of CYP2R1 gene may be novel genetic markers for T2DM in China. Given the lack of association between SNPs and serum 25(OH)D3 levels, well-designed future studies should be conducted with larger sample sizes in rural areas of China.

Objective: Recent studies have found that selenium (Se) levels were associated with the risk of Parkinson’s disease (PD), but the results were contradictory. Therefore, this meta-analysis was condu...

Background The effect of vitamin D supplementation on blood pressure has been explored in previous meta-analyses, but whether the association is causal in the general population is still unknown. We evaluated the association comprehensively and quantitatively. Methods We searched PubMed and Embase for relevant cohort studies and randomized controlled trials (RCTs). We used a 2-step generalized least-squares method to assess the dose-response association of circulating 25-hydroxyvitamin D (25[OH]D) and hypertension and a fixed-effects model to pool the weighted mean differences (WMDs) and corresponding 95% confidence intervals (95% CIs) of blood pressure across RCTs. Results We identified 11 cohort studies and 27 RCTs, with 43,320 and 3,810 participants, respectively. The dose-response relationship between circulating 25(OH)D levels and hypertension risk was approximately L-shaped (Pnonlinearity = .04), suggesting that the risk of hypertension increased substantially below 75 nmol/L as 25(OH)D decreased, but it remained significant over the range of 75-130 nmol/L. However, pooled results of RCTs showed that there was no significant reduction in systolic blood pressure (WMD, -0.00 mm Hg; 95% CI, -0.71 to 0.71) or diastolic blood pressure (WMD, 0.19 mm Hg; 95% CI, -0.29 to 0.67) after vitamin D intervention. Conclusions The results of this meta-analysis indicate that supplementation with vitamin D does not lower blood pressure in the general population. RCTs with long-term interventions and a sufficient number of participants who have low levels of vitamin D are needed to validate these findings.

We report neutron diffraction studies of FeS single crystals obtained from Rb(x)Fe(2−y)S(2) single crystals via a hydrothermal method. While no [Formula: see text] iron vacancy order or block antiferromagnetic order typical of Rb(x)Fe(2−y)S(2) is found in our samples, we observe C-type short-range antiferromagnetic order with moments pointed along the c axis hosted by a different phase of FeS with an expanded interlayer spacing. The Néel temperature for this magnetic order is determined to be 170 ± 4 K. Our finding of a variant FeS structure hosting this C-type antiferromagnetic order demonstrates that the known FeS phase synthesized in this method is in the vicinity of a magnetically ordered ground state, providing insights into understanding a variety of phenomena observed in FeS and the related FeSe(1−x)S(x) iron chalcogenide system.

Hydrothermal synthesis is described of layered lithium iron selenide hydroxides Li1-xFex(OH)Fe1-ySe (x ~ 0.2; 0.02 < y < 0.15) with a wide range of iron site vacancy concentrations in the iron selenide layers. This iron vacancy concentration is revealed as the only significant compositional variable and as the key parameter controlling the crystal structure and the electronic properties. Single crystal X-ray diffraction, neutron powder diffraction and X-ray absorption spectroscopy measurements are used to demonstrate that superconductivity at temperatures as high as 40 K is observed in the hydrothermally synthesised samples when the iron vacancy concentration is low (y < 0.05) and when the iron oxidation state is reduced slightly below +2, while samples with a higher vacancy concentration and a correspondingly higher iron oxidation state are not superconducting. The importance of combining a low iron oxidation state with a low vacancy concentration in the iron selenide layers is emphasised by the demonstration that reductive post-synthetic lithiation of the samples turns on superconductivity with critical temperatures exceeding 40 K by displacing iron atoms from the Li1-xFex(OH) reservoir layer to fill vacancies in the selenide layer, 7 pages supplementary material available from Journal, Inorganic Chemistry 2015

We report the synthesis and characterization of a rare-earth dichalcogenide EuTe$_2$. An antiferromagnetic transition was found at T$_M$ = 11 K. The antiferromagnetic order can be tuned by an applied magnetic field to access a first-order spin flop transition and a spin flip transition. These transitions are associated with a giant negative magnetoresistance with a value of nearly 100\%. Heat capacity measurements reveal strong electronic correlations and a reduced magnetic entropy. Furthermore, density functional theory calculations demonstrate that the electrons near the Fermi surface mainly originate from the Te 5$p$ orbitals and the magnetism is dominated by localized electrons from the Eu 4$f$ orbitals. These results suggest that both the RKKY and Kondo interactions between the local moments and itinerant electrons play crucial roles in the magnetism and large negative magnetoresistance of EuTe$_2$., Comment: 7 pages, 6 figures

Previous studies have suggested that vitamin D is associated with cardiovascular disease (CVD), however, the relationship between vitamin D levels and CVD risk is still unclear. The purpose of this study was to assess the relationship of serum concentration of 25-hydroxyvitamin D (25(OH)D) with CVD in rural residents of Henan province of China. Basic information and medical history were gathered through face-to-face surveys from July 2013 to August 2015, and biochemical indicators were gathered in a laboratory setting. Logistic and restricted cubic splines regression analyses were used to estimate odd ratios (ORs) and 95% confidence intervals (95%CI) of CVD. A total of 1078 participants were included, the mean serum 25(OH)D concentration was determined to be 25 ± 18 ng/ml, with 54.45% of the participants presenting vitamin D deficiency [25(OH)D < 20 ng/mL]. Moreover, the prevalence of CVD was 59.28% in the vitamin D deficient group, which was higher than in the insufficient (48.55%) and sufficient groups (52.78%). After adjusting for potential confounders, compared with the deficient group, the ORs (95%CI) of CVDs were 0.68 (0.50, 0.91) in the insufficient group and 0.81 (0.56, 1.16) in the sufficient group. A nonlinear (U-shaped) association was observed between the risk of CVD and 25(OH)D concentration. Further research suggested that the risk of CVD was higher in males than in females. In conclusion, a U-shape association between serum levels of 25(OH)D and the risk of CVD was identified in our study, suggesting a nonlinear relationship between vitamin D with the prevalence of CVD.

Table S1. Allele and genotype frequencies of VDR polymorphism and risk of overweight and obesity. Table S2. Allele and genotype frequencies of VDR polymorphism and risk of abdominal obesity (DOCX 20 kb)

Pterostilbene (PTE) is a natural dimethylated analog of resveratrol, which exerts antioxidative, hypolipidemic and hypoglycemic effects; however, the underlying mechanism is not yet clear. In this study, we evaluated the effects of PTE on diabetic rats and clarified the underlying mechanism. Diabetes was induced in rats by streptozotocin (STZ) and a high-sugar and high-fat diet. Rats were then treated with PTE (20, 40 and 80 mg/kg/d) for 8 weeks. Oral glucose tolerance test (OGTT) was performed to measure the glycometabolism of the diabetic rats at the end of the treatment. Fasting blood glucose (FBG), fasting insulin (FINS) and lipid profile were determined using an automatic biochemistry analyzer and serum inflammatory factors were analyzed by enzyme-linked immunosorbent assay. Serum superoxide dismutase (SOD) and malondialdehyde (MDA) were also analyzed by spectrophotometry to evaluate the anti-oxidant effects. The expression of proteins of PPARγ and PI3K/Akt signaling pathway related proteins in adipose tissue of the diabetic rats was analyzed by Western blotting. PTE treatment significantly reduced weight loss, FBG, insulin resistance, serum lipid levels and inflammatory factors. PTE treatment also inhibited oxidative stress by decreasing MDA expression and increasing SOD expression. Simultaneously, PTE treatment significantly ameliorated morphological impairment of the pancreas in diabetic rats. Furthermore, PTE treatment significantly increased the protein expression of PPARγ, PI3K, p-Akt, GLUT4 and IRS-1 in adipose tissues of diabetic rats. This study suggests that PTE can exert antidiabetic effects via the PI3K/Akt signaling pathway.

A low serum vitamin D concentration is associated with an increased risk of type 2 diabetes mellitus (T2DM). Recently, several single nucleotid polymorphisms (SNPs) have been identified which influence vitamin D levels. If a causal relationship exists between vitamin D concentrations and T2DM, one would expect a similar association between the newly identified SNPs and T2DM risk. Therefore, this study investigated the association between four SNPs of cytochrome P450 family 2, subfamily R, peptide 1 (CYP2R1) gene, serum 25(OH)DThree hundred and ninety-seven patients with confirmed T2DM, as well as 397 age- and gender-matched controls were enrolled in this case-control study. Genotyping was performed by TaqMan probe assays. Kruskal-Wallis one-way analysis and muitiple logistic regression analysis were performed to identify the possible risk genotype for vitamin D levels and T2DM, respectively. Generalized multifactor dimensionality reduction (GMDR) was used to analyze the gene-gene and gene-environment interactions.The serum 25(OH)DRs1993116 and rs10766197 polymorphisms of CYP2R1 gene may be novel genetic markers for T2DM in China. Given the lack of association between SNPs and serum 25(OH)D

Object To investigate the effects of sulforaphane (SFN) and vitamin E (VE) on spatial learning and memory ability and oxidative damage of hippocampus in lead-exposed mice at lactation. Methods A total of 18 adult Kunming mice, all 12 female mice were divided into two groups by body weight randomly, 10 mice drank water containing 0.2% lead acetate at lactation, the other 2 mice drank lead free deionized water named as the normal group. Then, they were mated at a 1:2 ratio of male to female. After weaning, the pups were divided into 5 groups by weight randomly (10 each group): normal saline (NS) group, corn oil (CO) group, SFN group, VE group and SFN + VE group. They were subject to gavage daily for four weeks. Gavage doses of SFN and VE were 25 mg/kg and 30 IU/kg respectively. Meanwhile, 10 pups of the normal group were selected randomly as the control (C) group. The C group was normally raised for 4 weeks. The spatial learning and memory ability of them were evaluated by the Morris water maze test, and the lead level in the blood was determined by polarography. Superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in hippocampus were measured by the kits. Results Compared with the NS and CO groups, the lead level in the blood of SFN and SFN + VE group had a significant decrease. In water maze test, the mice treated with SFN or/and VE performed better than mice of the NS and CO groups. In addition, a remarkable decrease in MDA level was found in mice treated with SFN or/and VE than those in NS and CO groups. What’s more, there was no statistical distinction of SOD activity in SFN group than that of NS group. SOD activity significantly increased was observed in VE and SFN + VE groups than that of CO group. Conclusion Sulforaphane and vitamin E could ameliorate cognitive decline and oxidative damage in pups with lead exposure at lactation from maternal milk.

The magnetic properties attributed to the hydroxide layer of ${\mathrm{Li}}_{1\ensuremath{-}x}{\mathrm{Fe}}_{x}(\mathrm{OH}){\mathrm{Fe}}_{1\ensuremath{-}y}\mathrm{Se}$ have been elucidated by the study of superconducting and nonsuperconducting members of this family of compounds. Both ac magnetometry and muon spin relaxation measurements of nonsuperconductors find a magnetic state existing below $\ensuremath{\approx}10$ K which exhibits slow relaxation of magnetization. This magnetic state is accompanied by a low-temperature heat capacity anomaly present in both superconducting and nonsuperconducting variants suggesting that the magnetism persists into the superconducting state. The estimated value of magnetic moment present within the hydroxide layer supports a picture of a glassy magnetic state, probably comprising clusters of iron ions of varying cluster sizes distributed within the lithium hydroxide layer.