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n-type Mg3Sb2-based materials have become a top candidate for efficient thermoelectric applications within 300–700 K, due to its high band degeneracy, inherently high carrier mobility and low lattice thermal conductivity, as well as its advantages of less toxicity and abundance. Existing works showed that Mg3Bi2-alloying largely help ensure the exceptional performance, leaving a key issue to be uncovered on the primary mechanisms favoring or limiting the thermoelectric performance of Mg3Sb2-xBix alloys. Here we focus on the alloy composition dependent transport properties at various temperatures, with a large volume of experimental data. It is revealed that, with increasing x, the reduction in both inertial mass and lattice thermal conductivity is significantly beneficial, but the closure in band gap leads to a strong compensation due to the bipolar effect. Such a compromise between band structure and phonon scattering results in optimal Mg3Bi2-alloying concentrations to be about 50%–75% at 300 K, 50%–60% at 450 K and 50% at 600 K, which successfully guiding this work to realize extraordinary thermoelectric figure of merit at these temperatures.

Over the past years, thermoelectric Mg3Sb2 alloys particularly in n-type conduction, have attracted increasing attentions for thermoelectric applications, due to the multivalley conduction band, abundance of constituents, and less toxicity. However, the high vapor pressure, causticity of Mg, and the high melting point of Mg3Sb2 tend to cause the inclusion in the materials of boundary phases and defects that affect the transport properties. In this work, a utilization of tantalum-sealing for melting enables n-type Mg3Sb2 alloys to show a substantially higher mobility than ever reported, which can be attributed to the purification of phases and to the coarse grains. Importantly, the inherently high mobility successfully enables the thermoelectric figure of merit in optimal compositions to be highly competitive to that of commercially available n-type Bi2Te3 alloys and to be higher than that of other known n-type thermoelectrics at 300-500 K. This work reveals Mg3Sb2 alloys as a top candidate for near-room-temperature thermoelectric applications.

BackgroundAs the most common chronic disease, hypertension is an important high-risk factor for cardiovascular and cerebrovascular diseases and vascular events. Previous studies have found that acupuncture has the effect of lowering blood pressure, but there is currently a lack of real-world research evidence for acupuncture to lower blood pressure.ObjectiveTo evaluate the blood pressure control effect of Huoxue Sanfeng acupuncture on hospitalized patients with cerebral infarction and hypertension in the real world.MethodsPatients with cerebral infarction and hypertension meeting the inclusion and exclusion criteria in the acupuncture ward of First Teaching Hospital of Tianjin University of Traditional Chinese Medicine from January 2014 to April 2020 were selected. There were 10 781 patiens who met the inclusion and exclusion criteria. According to whether the Huoxue Sanfeng acupuncture method was applied during hospitalization, the patients were divided into basic treatment group (n=10 424) and Huoxue Sanfeng group (n=357) . The propensity score matching (PSM) was used to obtain a new sample with balanced covariates between groups, and the linear mixed effects model was used to compare the average daily blood pressure and morning blood pressure of the two groups in the new sample, which was used to evaluate the effect of Huoxue Sanfeng acupuncture in controlling blood pressure.ResultsThere was no statistically significant difference in gender, age, coronary heart disease, diabetes, atrial fibrillation, the levels of HCY, TC, TG, LDL, and Cr levels before matching (P>0.05) , while the levels of HDL and Ur in basic treatment group were higher than those in the Huoxue Sanfeng group (P0.05) . The results of the linear mixed effect model showed that the average systolic blood pressure in the Huoxue Sanfeng group was lower than the basic treatment group (P=0.002) ; the average level of diastolic blood pressure in the Huoxue Sanfenggroup and the basic treatment group was not statistically significant difference (P=0.083) ; there was no interaction between treatment methods and hospital admission time (P=0.532, P=0.775) . The results of the mixed effect model showed that after the intervention of different treatments, the systolic blood pressure in theHuoxue Sanfenggroup was lower than the basic treatment group in the morning (P=0.012) ; the morning diastolic blood pressure of the Huoxue Sanfenggroup and the basic treatment group was not statistically significant difference (P=0.539) ; there was no interaction between the treatment method and hospital admission time (P=0.974, P=0.985) .ConclusionHuoxue Sanfeng acupuncture can further control the daily average systolic blood pressure and early morning systolic blood pressure in hospitalized patients with cerebral infarction and hypertension.

Some rare earth elements are occupational and environmental toxicants and can cause organ and systemic damage; therefore, they have attracted global attention. Neodymium oxide (Nd2O3) is a rare earth element that is refined and significantly utilized in China. The long noncoding RNA (lncRNA) H19 is encoded by the H19/IGF2 imprinted gene cluster located on human chromosome 11p15.5. H19 has become a research focus due to its ectopic expression leading to the promotion of fibrosis. However, the mechanisms by which it causes pulmonary fibrosis are elusive. This investigation indicates that biologically active Nd2O3 increases H19, SNIP1, and c-myc, decreases miR-29a-3p, accelerates macrophage M2 polarization, and causes pulmonary fibrosis in mice lung tissues. In macrophage-differentiated THP-1 cells, Nd2O3 (25 μg/ml) enhanced H19, SNIP1, and c-myc, reduced miR-29a-3p, accelerated macrophages M2 polarization, and stimulated fibrogenic cytokine (TGF-β1) secretion. Furthermore, the coculturing of Nd2O3-treated macrophage-differentiated THP-1 cells. And human embryonic lung fibroblast cells activated lung fibroblast, which increases the levels of collagen I, α-SMA, p-Smad2/3, and Smad4, whereas H19 knockdown or miR-29a-3p upregulation in macrophages had opposite effects. Moreover, it was revealed that H19/miR-29a-3p/SNIP1/c-myc regulatory axis is involved in pulmonary fibrosis induced by Nd2O3. Therefore, this study provides new molecular insights into the mechanism of pulmonary fibrosis by Nd2O3. [ABSTRACT FROM AUTHOR]