Decrease In Tc Research Articles

Effects of Antioxidants (Micronutrients) with Metformin in type 2 Diabetic patients

Objectives: This study aims to investigate the effect of antioxidants (Micronutrients) with Metformin on the levels of sugar and lipids in type 2 diabetic patients. Methods: The study has been conducted on 32 persons having the disease of type 2 diabetes. The patients were divided randomly into two groups labeled as B and C. All patients in each group have been taking metformin and additional specific treatment has been provided to group B. The samples have been collected before taking medicine (Antioxidants) and after three months of taking it. Blood samples were collected after 12 hours of overnight fasting where blood samples were drawn before and after a meal from the patients to measure levels of the sugar and lipids. The method that has been used for doing these investigations is Kit Spinreact. The results were analyzed statistically. Results: A significant decrease in FBS, PPBS, HbA1c, TC, TG, LDL and VLDL has been observed whereas the results showed increasing significance in HDL level in the patients of group B which received antioxidants (Muvit Gold) and Metformin compared to group C which received Metformin only. In conclusion, the results indicate that daily consumption of supplementary antioxidants (micronutrient) with Metformin leads to improving the level of blood glucose and lipids in patients with Type 2 diabetes and reducing the risk of complications. Hence, the dose of combining micronutrient with metformin can be used in the treatment of Type 2 diabetes by maintaining good glycemic control.

The influence of heating on the carbon isotope composition, organic geochemistry and petrology of coal from the Upper Silesian Coal Basin (Poland): An experimental and field study

The impact of natural intra-deposit heating on the δ13C signature, organic geochemistry, and petrology of coal and coal-bearing rocks characterised by various degrees of coalification and palaeoenvironments in the Upper Silesian Coal Basin, Poland, is elaborated. Reconstruction of palaeofire performed by heating experiments up to 400 °C in open and semi-closed systems with different heating regimes confirms the crucial significance of temperature and oxygen access. In open-system heating, released 13C-depleted gases enrich residue coke in 13C compared to raw coal. Petrological examinations did not show the impact of palaeofires on the maceral properties of coal. However, the carried-out experiment caused the formation of devolatilisation pores, rounded edges, cracks, pale rims, as well as higher reflectance and paler colour that was what was expected. Extractable compounds become highly depleted, and low-weight organic compounds nearly absent. Relatively high contents of combustion-formed PAHs are an indicator of open-system heating. In semi-closed systems, the final total isotopic composition was almost unchanged as no components are carried away though changes in petrography and geochemistry occur. Increased extract yields reflect the release of bitumen from closed pores and partial pyrolysis of organic matter. Depletion of lighter n-alkane compounds, total carbon TC and volatiles decrease, and variable values of various alkyl aromatic hydrocarbon ratios are also indicative of semi-closed heating. Coal seams suspected of intra-deposit heating show geochemical and isotopic features similar to semi-closed- rather than open-system heating, and their δ13C signatures and organic geochemistry did not respond strongly during laboratory re-heating.

Structure evolution and enhanced electrical performance for BiScO3–Bi(Ni1/2Zr1/2)O3–PbTiO3 solid solutions near the morphotropic phase boundary

In this work, the Bi(Me)O3–PbTiO3-type (1-x-y)BiScO3-xBi(Ni1/2Zr1/2)O3-yPbTiO3 (BS-xBNZ-yPT) ternary piezoelectric ceramics have been prepared with x ≤ 0.075 by the traditional solid-state reaction methods. For compositions with x > 0.100, the Curie temperature (Tc) will reduce below 400 °C. X-ray powder diffraction results demonstrate the system a single perovskite phase structure. Analyzed the phase structure evolutions, it can be found the MPB of this BS-xBNZ-yPT ternary solid solutions shifts to the low PT content regions with the increasing BNZ content. Dielectric diffuse behaviour in this system may result from the production of polar nanodomains by the introduction of BNZ. The piezoelectric performance is enhanced with only a little decrease in Tc by the introduction of small content BNZ. The most promising composition BS-0.025BNZ-0.635PT exhibits the piezoelectric constant d33 of 480 pC/N, planar electromechanical coupling coefficients kp of 58.2%, and Curie temperature Tc of 439 °C, respectively. The unipolar strain was found up to 0.233% with the small strain hysteresis of 11.4%. All these properties together with the good thermal stability indicate the BS-xBNZ-yPT ceramics potential candidates for high temperature piezoelectric actuator application.

EFFECT OF CONTINUOUS POSITIVE AIRWAY PRESSURE TREATMENT ON GLYCEMIC AND LIPID PROFILES IN PATIENTS WITH OBSTRUCTIVE SLEEP APNEA: A SYSTEMATIC REVIEW AND META-ANALYSIS

Objective: Continuous Positive Airway Pressure (CPAP) is the main therapy for obstructive sleep apnea (OSA); nevertheless, uncertainty remains about the effectiveness of CPAP not only in controlling OSA-related hypertension, but also in improving the metabolic dysregulation that characterizes OSA patients. This meta-analysis of randomized controlled trials (RCTs) aimed to investigate whether CPAP, compared to other control treatments (sham CPAP, oral placebo or standard care), could improve glucose metabolism (fasting plasma glucose [FPG] or glycated haemoglobin or fasting plasma insulin [FPI] or homeostasis model assessment [HOMA] of insulin resistance [IR]) and/or lipid metabolism (total, HDL, LDL-cholesterol or triglycerides) in OSA patients. Design and method: Relevant papers were searched in three different databases (MEDLINE, EMBASE and Web of Science) from inception to 31st Dec 2018 through specific search terms and selection criteria. Results: From 2,289 articles, 26 RCTs were included. Regarding glycemic metabolism, neither FPG nor glycated haemoglobin were reduced by CPAP. However, patients on CPAP showed an improvement in insulin sensitivity, as witnessed by a significant reduction of FPI (Standardized difference in means [SDM] = 0.205 [95%CI, 0.07–0.339], p = 0.003) and HOMA IR (SDM = 0.176 [95%CI, 0.056–0.296], p = 0.004). In sensitivity analysis the favourable effects of CPAP were maintained in prediabetic/type 2 diabetic patients and in those presenting an apnoea-hypopnea index > 30 events/h. Regarding lipid metabolism, OSA patients treated with CPAP showed a significant reduction in total cholesterol (TC; SDM = 0.138 [95%CI, 0.034–0.242], p = 0.009). In subgroups analysis, greater adherence to CPAP along with severe nocturnal oxygen desaturations at baseline (SpO2-nadir < 77%) was associated with a significant decrease of TC. Furthermore, dividing the primary studies according to the median TC at baseline (198 mg/dL), the positive effects of CPAP were maintained only in those that presented a TC above the median. Conversely, CPAP did not modify triglycerides, HDL- and LDL-cholesterol. Conclusions: CPAP treatment significantly improves insulin sensitivity and reduces TC in OSA patients but with a low effect size. The effectiveness of CPAP is higher in patients with greater CPAP usage, and with a greater number of apnoeic events and oxygen desaturations at baseline. Concerning TC, patients presenting higher levels at baseline benefit the most from CPAP.

Nominal Effect of Mg Intercalation on the Superconducting Properties of 2H-NbSe2.

2H-NbSe2 is a phonon-mediated, Fermi-surface topology-dependent multiband superconductor with an incommensurate charge-density wave (CDW) that coexists at a local level with superconductivity. Usually, the intercalation in 2H-NbSe2 enriches the CDW, enhances the c-axis lattice parameter, and distorts the Fermi surface, which result in a decrease in the superconducting transition temperature (Tc). The rate of decrease of Tc depends on the electronic structure, size, valence, magnetic nature, and electronegativity of the intercalating species. Herein, we report an unusual effect of Mg intercalation on the superconductivity of 2H-MgxNbSe2 (x = 0.0, 0.02, 0.06, 0.08, 0.10, and 0.12) synthesized by a high-temperature solid-state reaction method. Unlike other s- and p-block elements/species as intercalants (Rb, Sn, Ga, and Al) that have a sharp detrimental effect on the Tc of 2H-NbSe2 within 1-5% of intercalation, Mg is found to be an exception. Upon Mg intercalation up to x = 0.06, no remarkable changes in Tc as compared to the parent 2H-NbSe2 (Tc ∼ 6.7 K) are observed, and further intercalation results in a small decrease in Tc (for x = 0.12, Tc = 6.2 K). From heat-capacity measurements, it is inferred that superconducting Mg-intercalated 2H-NbSe2 exhibits strong electron-phonon coupling. Electronic structure calculations on two s-block element intercalated compounds of formula M0.125NbSe2 (M = Mg, Rb) show that Rb s-, p-, and d-states completely overlap with the Nb d states, while the Mg s states lie in a low-energy region as compared to Nb d states, indicating a weak interaction between the intercalant and the Nb sublattice in Mg0.125NbSe2 as compared to Rb0.125NbSe2. These results suggest that the electronic states of the Nb network in 2H-NbSe2 are least altered with Mg intercalation, which could be one of the reasons for the minimal effect on the Tc with intercalation.

Mendelian Randomization Highlights the Causal Role of Normal Thyroid Function on Blood Lipid Profiles.

The association between thyroid function and dyslipidemia has been well documented in observational studies. However, observational studies are prone to confounding, making it difficult to conduct causal inference. We performed a 2-sample bidirectional Mendelian randomization (MR) using summary statistics from large-scale genome-wide association studies of thyroid stimulating hormone (TSH), free T4 (FT4), and blood lipids. We chose the inverse variance-weighted (IVW) method for the main analysis, and consolidated results through various sensitivity analyses involving 6 different MR methods under different model specifications. We further conducted genetic correlation analysis and colocalization analysis to deeply reflect the causality. The IVW method showed per 1 SD increase in normal TSH was significantly associated with a 0.048 SD increase in total cholesterol (TC; P < 0.001) and a 0.032 SD increase in low-density lipoprotein cholesterol (LDL; P = 0.021). A 1 SD increase in normal FT4 was significantly associated with a 0.056 SD decrease in TC (P = 0.014) and a 0.072 SD decrease in LDL (P = 0.009). Neither TSH nor FT4 showed causal associations with high-density lipoprotein cholesterol and triglycerides. No significant causal effect of blood lipids on normal TSH or FT4 can be detected. All results were largely consistent when using several alternative MR methods, and were reconfirmed by both genetic correlation analysis and colocalization analysis. Our study suggested that, even within reference range, higher TSH or lower FT4 are causally associated with increased TC and LDL, whereas no reverse causal association can be found.

Pressure-induced structural transition and huge enhancement of superconducting properties of single-crystal Fe0.99Ni0.01Se0.5Te0.5 unconventional superconductor

We report high-pressure structural studies (52 GPa) at room temperature combined with magnetic [(M(T):1GPa] and electrical resistivity [(ρ(T):0-21GPa)] measurements down to 2 K on Fe0.99Ni0.01Se0.5Te0.5 superconductor using designer diamond anvils (D-DAC) pressure cell. The M(T) data show huge enhancement of superconducting transition temperature (Tc) from 8.62 to 14.8 K (1 GPa) and ρ(T) reveal maximum enhancement of Tc ~ 30.5 K at 3 GPa (dTc/dP = ~ 7.19 K/GPa) followed by moderate decrease of Tc up to 19 K at 7.5 GPa, and further increasing pressure Tc gets vanished at 10.6 GPa. The reduction of Tc due to the occurrence of structural transition that is likely associated with possible reduction of charge carriers in the density of states in Fermi surface. The high-pressure XRD measurement shows tetragonal phase exists up to 7 GPa, followed by mixed phase which is visible between 7.5 GPa and 14.5 GPa. The structural transformation occurs at 15 GPa from tetragonal (P4/nmm) to NiAs -type hexagonal phase (P63/mmc) and it is stable up to 52 GPa, confirmed from the equation of state (EOS) and it can be correlated with variation of Tc under pressure for Fe0.99Ni0.01Se0.5Te0.5 chalcogenide superconductors.

Application of Molecular Hydrogen in Heart Surgery under Cardiopulmonary Bypass.

The aim of this work was to study the effect of molecular hydrogen on oxidative processes in cardiac surgery patients with acquired valve heart disease applied during surgery under cardiopulmonary bypass (CPB).Materials and Methods.The study involved 20 patients (16 men and 4 women) with acquired heart valve disease who were operated on under CPB. Two groups of patients were formed. In group 1 (n=11), anesthesia included inhalations of molecular hydrogen, which was supplied to the breathing circuit of the ventilator at a concentration of 1.5–2.0% immediately after tracheal intubation and throughout the operation. In group 2 (n=9), inhalation of molecular hydrogen was not performed. Blood sampling was taken at 4 stages: immediately after anesthesia induction, before CPB and after its termination, and also one day after the operation. The intensity of the processes of lipid peroxidation was evaluated by the level of diene (DC) and triene (TC) conjugates, Schiff bases (SB).Results.In the patients of group 1, the arterial blood samples showed a decrease in the level of TC and SB, as compared to the first stage of the study, before the initiation of CPB and one day after the operation. An increase in the level of DC and TC was detected after the termination of CPB (p<0.05). In the venous blood samples, an increase in the level of DC was noted before the initiation of CPB, which was restored by the third stage of the study (p<0.05). At the same time, after the termination of CPB, a tendency towards a decrease in TC and SB was observed, which persisted one day after the operation.In the patients of group 2, an increase in the concentration of SB in the arterial blood samples was recorded during the study as compared to the first stage. The level of TC and SB in the venous blood samples increased one day after the operation.Conclusion.Intraoperative inhalation of molecular hydrogen leads to a decrease in the oxidative stress manifestation, it being most pronounced one day after the operation. This suggests that molecular hydrogen can be used in cardiac surgery as an effective and safe antioxidant.

Superconducting properties of GdxPb1−xMo6S8 (x = 0.5, 0.7, 0.9) compounds

For the first time, the temperature dependences of the electrical resistivity ρ(T) were studied in GdxPb1−xMo6S8 (x = 0.5, 0.7, 0.9) compounds in the temperature range 4–18 K and magnetic fields up to 14 T. It is shown that the superconducting transition temperature values Tc decrease from 14.6 K for a compound with x = 0.5 to 11.8 K for x = 0.9. Experimental dependences Hc2(T) were plotted and it was found that the theoretical dependence Hc2(T) within the microscopic theory of Werthamer-Helfand-Hohenberg poorly describes the experimental data for the Gd0.9Pb0.1Mo6S8 compound. At the same time, the fit of Hc2(T) within the Ginzburg-Landau theory is in good agreement with the experimental results for all the studied samples. An explanation of the dependence Hc2(T) of the studied samples from the gadolinium concentration was proposed. The differential resistance for the Gd0.5Pb0.5Mo6S8–Ag heterocontact with resistance RPC ≈ 2.6 Ω was obtained for 2.6 K using point-contact Andreev reflection spectroscopy. As a result, the superconducting gap for Gd0.5Pb0.5Mo6S8 was estimated for the first time to be Δ ≈ 1.95 meV at 2.6 K. The resulting ratio was 2Δ/kTc ≈ 3.02, which is lower than the Bardeen–Cooper–Schrieffer value of 3.52 for conventional weakly coupled superconductors.

Internal and External Pressure Effects on Superconductivity in FeTexSe1-x (x = 0.46, 0.54) Single Crystals

We have synthesized and studied the transport properties of FeTexSe1-x (x = 0.4, 0.46, 0.5, 0.54, and 0.58) single crystals grown by slow cooling method and found a sharp increase of Tc up to x = 0.46 followed by a moderate decrease of Tc up to x = 0.58. We present the temperature dependence of electrical resistivity under various pressures up to ~ 2.5 GPa, and the pressure dependence of Tc shows positive pressure coefficients of ~ 2.7 K/GPa and ~ 3.33 K/GPa for x = 0.46 and x = 0.54, respectively, up to 2 GPa followed by a decreasing trend with marginal variation of Tc with negative pressure coefficients of − 0.602 K GPa−1 (x = 0.46) and − 0.7 K GPa−1 (x = 0.54) at maximum pressure of 2.5 GPa. Furthermore, both normal state resistivity and activation energy decrease sharply, and it suggests that the reduction of net electron-phonon scattering and densities of states (DOS) at the Fermi surface with application of pressure leads to enhancement of metallic behavior in FeSe systems.

Anomalous Charge Density Wave State Evolution and Dome-Like Superconductivity in CuIr &lt;sub&gt;2&lt;/sub&gt;Te &lt;sub&gt;4-X&lt;/sub&gt;Se &lt;sub&gt;x&lt;/sub&gt;

The interplay between superconductivity (SC) and the charge density wave (CDW)-like order in CuIr2Te4 is systematically explored through Se substitution for Te site through the powder X-ray diffraction (PXRD), magnetic susceptibility, resistivity measurements and heat capacity. CuIr2Te4-XSex (0 ≤ x ≤ 0.5) compounds retain the same structure as the host CuIr2Te4. The unit cell parameters a and c decrease linearly with increasing Se content. Tc exhibits a weak dome-like variation as substituting Te by Se with the maximum Tc = 2.83 K for x = 0.1 followed by suppression in Tc and simultaneous decrease of the superconducting volume fraction. Unexpectedly, the CDW-like transition (TCDW) is suppressed with lower Se doping (0.025 ≤ x ≤ 0.2) but re-emerge at higher doping (0.25 ≤ x ≤ 0.5). We propose that it arises from the disorder effect by chemical doping. The lower and the upper critical field and these compounds are also addressed.

Magnetic properties of La0.55CaxSr0.45−xMnO3 perovskite manganite

Conventional solid-state reaction technique was used to prepare the studied samples La0.55CaxSr0.45−xMnO3 (x = 0.0, 0.1, 0.2). Their structural and magnetic properties have been investigated to find the effect of calcium doping on the D.C. and A.C. magnetic properties of the compounds. Room temperature XRD investigations confirm rhombohedral structure with space group R-3c for all the samples. Lattice parameter is found to decrease with increase in Ca(x) content. Microstructure was examined from the images taken by Scanning Electron Microscopy (SEM) and chemical compositions were determined by an energy dispersive X-ray diffractometer (EDX). The zero-field cooled (ZFC) and field cooled (FC) DC magnetization measurements reveal paramagnetic (PM) to ferromagnetic (FM) transition in them upon cooling through their Curie temperature (TC). But the FM state coexists with the residual canted anti-ferromagnetic state rather than a pure FM state in the samples. The TC values are dependent on Ca(x) content of the samples. Moreover, XRD analysis and EDX data reveals the presence of Mn deficiency in the studied samples. Presence of minor secondary Mn3O4 phase creates this deficiency resulting a significant decrease in TC and strongly influences the magnetic properties. The values of A.C. permeability (μʹ) also depend on Ca(x) content as well as grain size that can be explained by Globus equation. However, μʹ values of the samples remain almost constant over a wide range of frequency which indicates the compositional stability of the perovskites. The magnetic modulus demonstrates the dynamics of their A.C. permeability by screening out the stray/any other effects in them. The Nyquist plots of magnetic modulus of the samples show the type of their magnetic relaxation.

Тепловые и магнитокалорические свойства манганитов La-=SUB=-0.7-=/SUB=-Sr-=SUB=-0.3-x-=/SUB=-Ba-=SUB=-x-=/SUB=-MnO-=SUB=-3-=/SUB=-

The results of a study of the effect of partial substitution of Sr2+ ions by Ba2+ ions on the thermophysical and magnetocaloric properties of manganite La0.7Sr0.3-xBaxMnO3 (x = 0; 0.02; 0.05 and 0.10) in the temperature range 100-400 K and in a magnetic field up to 1.8 T. It is shown that such a substitution leads to a significant decrease in TC. In the behaviour of the thermal diffusivity (T) and thermal conductivity (T) near TС, minima were found that are associated with both the scattering of phonons by local distortions of the crystal lattice and by spin fluctuations. The absolute values of thermal conductivity decrease with an increase in the disorder parameter. The magnetocaloric effect exhibits a weak dependence on the substitution level (x).

Magnetic doping effects on the superconductivity of Y1-xMxBa2Cu3O7-δ (M = Fe, Co, Ni)

The discovery of superconductivity in copper oxide compounds has attracted considerable attention over the past three decades. The high transition temperature (Tc) in these compounds, exhibiting proximity to an antiferromagnetic order in their phase diagrams, remains one of the main areas of research. It is believed that magnetic fluctuations provide substance for the exotic superconductivity observed in these compounds. The present study attempts to introduce Fe, Co and Ni magnetic impurities into the superconducting cuprate YBa2Cu3O7-δ with the aim of exploring the Tc behavior. The solid-state synthesis method is exploited to prepare fully oxygenated Y1-xMxBa2Cu3O7-δ (Y1-xMx-123) (M = Co, Fe, Ni) samples with low levels of doping (0.00000 ≤ x ≤ 0.03000). Systematic measurements are then employed to assess the synthesized samples using AC magnetic susceptibility, electrical resistivity and X-ray diffraction (XRD). The measurements revealed an increase in Tc as a result of magnetic substitution for Y. However, the study of non-magnetic dopings on the fully oxygenated Y1-xM'xBa2Cu3O7-δ (Y1-xM'x-123) (M' = Ca, Sr) samples showed a decrease in Tc. Quantitative XRD analysis further suggested that the internal pressure could have minor effects on the increase in Tc. The normal state resistivity vs temperature showed a linear profile, confirming that the samples are at an optimal doping of the carrier concentration.

Universal proximity effects in hybrid superconductor–linker molecule–nanoparticle systems: The effect of molecular chirality

The superconductor proximity effect in systems comprising metallic nanoparticles (NPs) and molecules (NP/molecule/superconductor heterostructure) is an intriguing phenomenon that gives rise to important questions, from both fundamental and applicative perspectives, about the nature of Andreev reflections in nanoscale NPs and molecules and the interplay between the different energy scales, which remain hotly debated. In recent studies of such systems, a unique proximity effect was observed, manifested by an enhancement, rather than reduction, of the superconductor critical temperature, TC, which can be related to higher order Andreev reflections of Cooper pairs that couple through the organic molecule linkers. In the present study, we investigate the proximity effect in such hybrid systems, using two types of superconducting films (Nb0.17Re0.83 and Nb), coupled Au or Ag NPs, via chiral or non-chiral molecule linkers. Non-chiral linkers lead to an enhancement of TC after NP attachment, in agreement with previous results, while chiral linkers cause a decrease in TC following NP adsorption. The results with chiral linkers can be explained by the following possible factors: the magnetic-like behavior that chiral molecules exhibit owing to their spin-filtering properties, which should enhance pair breaking, and strong spin–orbit coupling at the linker/NP interface that affects Andreev reflections between the superconductor and the NP and acts to reduce TC within a two-band model we discuss. The insight gained from this work into the interaction between chiral molecules and superconductors is of importance for applications in chiral-based superconducting spintronics.

Antidiabetic Activity of &lt;i&gt;Anemarrhena asphodeloides&lt;/i&gt; Bge. Polysaccharides

The present study was aimed to investigate the anti-diabetic activity of Anemarrhena asphodeloides Bge. Polysaccharides (AAP). Wistar rats were injected with streptozotocin(STZ)to induce diabetes. The APP was prepared at first. After the rats were orally administered for 28 days, related biochemical indicator were determined. AAP was composed of mannose, galacturonic acid, galactose, glucose and xylose in the molar ratio of 12:8.1:2.7:1.3:1 with the average molecular weight of 52.4 kDa. After treatment with AAP (100 and 200 mg·kg-1) for 28 days there was a significant decrease in blood glucose, SGPT, SGOT, ALP, TC, TG, LDL, BUN and significant increase in body weight, fasting serum insulin, pancreatic insulin and HDL. The activities of SOD and CAT in liver and kidneys also increased. The results of the experiments showed that AAP exerted significant anti-diabetic activity.

Tailoring Superconductivity in Large-Area Single-Layer NbSe2 via Self-Assembled Molecular Adlayers.

Two-dimensional transition metal dichalcogenides (TMDs) represent an ideal testbench for the search of materials by design, because their optoelectronic properties can be manipulated through surface engineering and molecular functionalization. However, the impact of molecules on intrinsic physical properties of TMDs, such as superconductivity, remains largely unexplored. In this work, the critical temperature (TC) of large-area NbSe2 monolayers is manipulated, employing ultrathin molecular adlayers. Spectroscopic evidence indicates that aligned molecular dipoles within the self-assembled layers act as a fixed gate terminal, collectively generating a macroscopic electrostatic field on NbSe2. This results in an ∼55% increase and a 70% decrease in TC depending on the electric field polarity, which is controlled via molecular selection. The reported functionalization, which improves the air stability of NbSe2, is efficient, practical, up-scalable, and suited to functionalize large-area TMDs. Our results indicate the potential of hybrid 2D materials as a novel platform for tunable superconductivity.

Tunable structural and magnetic properties of NiAs-type MnxSb (1.00[formula omitted]x[formula omitted]1.30) compounds

Mn-based alloys can exhibit a variety of magnetic properties related to their tunable exchange interactions. In this work, structural and magnetic properties of hexagonal NiAs-type MnxSb (1.00≤x≤1.30) compounds are studied with a combination of X-ray diffraction, neutron diffraction, and magnetic measurements. It is found that the magnetization, Curie temperature, and magnetocrystalline anisotropy of MnxSb compounds can be tuned by controlling Mn concentration and doping at interstitial (2d) sites. With increasing Mn concentration, magnetic moments of Mn atoms decrease and deviate gradually from the ab-plane to the c-axis for 1.20≤x≤1.22 at room temperature, which leads to a decrease of the Curie temperature Tc and the spin reorientation temperature TSR. By doping with nonmagnetic elements, a substantial room-temperature magnetocaloric effect without magnetic hysteresis was achieved for Mn1.12Zr0.1Sb compound, which is highly beneficial to the practical magnetic refrigeration application.

The effects of magnesium and vitamin E co-supplementation on some cardiovascular risk factors: A meta-analysis.

Growing attention has been paid to use the combination of magnesium and vitamin E, which might improve metabolic profiles in patients with metabolic diseases. Consequently, we conducted a meta-analysis of published randomized controlled trials (RCTs) to systematically analyze the effects of magnesium and vitamin E co-supplementation on some cardiovascular risk factors in patients with metabolic disorders. We searched the National Library of PubMed, Scopus, Web of Science, the Cochrane library and Embase databases for studies published before February 2020 and included controlled trials in which used mentioned intervention. Finally, we extracted 4 trials satisfying our selection criteria. Two reviewers selected studies independently of each other and if they disagreed, was asked a third reviewer. The risk of bias of individual studies was assessed using the Cochrane Collaboration risk of bias tool. Data were pooled using the random-effects method and were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI). A total of 4 studies meet the eligibility criteria. 119 individuals allocated to intervention and 118 participants allocated to control group. Our meta-analysis indicated that the co-supplementation with magnesium and vitamin E resulted in a significant decrease in FPG, Insulin, HOMA-IR, TG, TC, and LDL-C in comparison with placebo. The co-supplementation with magnesium and vitamin E had no significant effects on the body weight, BMI, and HDL. However, there were no significant heterogeneity for all of the variables except for FPG (I2=56.0%, P=0.103) and TG (I2=80.7%, P=0.006). Our meta-analysis indicated that the co-supplementation with magnesium and vitamin E resulted in a significant decrease in FPG, Insulin, HOMA-IR, TG, LDL-C. Moreover, no significant effects on the body weight, BMI and HDL were observed. However, the glycemic-improving properties of magnesium and vitamin E co-supplementation were small and may not reach clinical importance.

Magnetic Properties of Eu8GaxGe46−x (Nominal x = 16, 14, and 12) Type-I Clathrates

Melt-spinning technique can widen the range of Ga content in Eu8GaxGe46−x type-I clathrate. In this paper, it was used to obtain Eu8GaxGe46−x with nominal 16 ≥ x ≥ 10. Three samples with nominal x = 16, 14, and 12 are discussed in detail. Their actual Ga contents detected by EDS are 14.3, 13.4, and 11.5, which is a relatively wide range that has not been reported before. The decrease of Ga content results in the decrease of lattice parameter a. Moreover, a huge decline of the ferromagnetic transition temperature TC is observed. It is 34.7 K, 27.0 K, and 20.0 K for Eu8GaxGe46−x with nominal x =16, 14, and 12, respectively. However, the saturation magnetic moment μsat and effective magnetic moment μeff are not greatly affected by the change of Ga content. The decrease of TC is mainly attributed to the decrease of molecular field coefficient λ, which can be calculated by fitting the relation curve between exchange mean field Hexch and magnetization M. The fitted λ values are 0.25, 0.18, and 0.16 for samples with nominal x = 16, 14, and 12. Because the decrease of TC is beneficial to the increase of magnetic entropy change, the maximum value of magnetic entropy change ( $$ - \Delta S_{{_{\text{M}} }}^{ \text{max} } $$ ) around TC when $$ \Delta H $$ = 3 T increases from 6.0 to 7.0 J/(kg K) as x decreases from 16 to 12.