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By combining the effects of defect engineering, band convergence, and carrier concentration tuning, we successfully suppress the lattice thermal conductivity to ultra-low 0.35 W m−1 K−1 and realize one of the highest ZT values of 1.75 at 833 K.

The need for cognition has much promise in predicting academic success. This study examined the relationship between the need for cognition and the personality traits of openness to experience and conscientiousness. The goal was to show that openness to experience and conscientiousness were significant predictors of the need for cognition, while finding which one has stronger predictive power. The data was collected from 300 American users of the website Amazon Mechanical Turk who completed the study online in exchange for monetary compensation. The participants were composed of 154 males and 145 females, and one individual with unreported gender. The participants ranged from 20 years of age to 71 years of age, with an average age of 37.4. The need for cognition was measured using the Need for Cognition Scale. The two personality traits were measured using the Ten-Item Personality Inventory. The results of the study indicated that openness to experience was a stronger predictor of the need for cognition and predicted more variance in the need for cognition.

Thermoelectric technology is an effective strategy to convert low–grade waste heat to electrical energy directly. Thermoelectric generators (TEGs) have been extensively studied in various waste heat scenarios, such as vehicle exhaust, metal casting processes and more. However, industrial pipelines also possess high levels of heat and wide distribution, yet there is limited research on TEGs for use in these pipes. The challenge in designing a TEG lies in the heat collector, which is complicated by the distinct structural differences between pipe and plate–shaped TEMs. Ultimately, we propose an arch bridge–shaped heat collector for the pipe to recover wasted thermal energy. The effects of some key factors, such as topology of TEMs, heat source temperature, cooling water temperature and velocity, on the generating performance are studied. The TEG achieved a temperature difference of 65.98 °C across the two ends of the TEM, resulting in an output power of 17.89 W at an open–circuit voltage of 133.35 V. This provides evidence that the designed heat collector is a feasible solution for recovering waste heat from pipes using TEG technology. This work provides reliable experimental data and efficient design for the application of TEGs in industrial pipes.

A nano h-BN composite realizes a better thermoelectric performance of ZTmax = 1.3 at 375 K and significantly improves the compressive strength to 8.8 MPa in zone-melted Bi2Te3-based materials.

Zone-melted Bi2Te3-based alloys are the only commercially available thermoelectric (TE) materials, but they suffer from mediocre figure of merit (ZT) values and brittleness. In this work, we prepared Bi0.48Sb1.52Te3 sintered samples using a hot-pressing method and added tiny AgCuTe to improve the comprehensive properties. Because the carrier concentration is boosted by the AgCuTe addition, the bipolar effect at higher temperature is explicitly suppressed and the power factor is also improved in a broad temperature scope. Simultaneously, κlat is mostly diminished by the introduced phonon scattering centers comprising point defects, dislocations, and grain boundaries. Consequently, we achieved a ZTmax of 1.25 at 350 K and its average ZTave of 1.1 from 300 to 500 K in the (Bi0.48Sb1.52Te3 + 3 wt % Te) + 0.12 wt % AgCuTe sample. Composed of this sample and commercial Bi2Te2.5Se0.5, the fabricated TE module manifests a maximum power output density of 0.31 W cm-2 (Tcold = 300 K and Thot = 500 K). This work suggests that AgCuTe-doped Bi0.48Sb1.52Te3 is promising for recovering low-grade thermal energy near room temperature.

CREBBP, in short CBP, has been reported to be involved in tumorigenesis in various cancers, but its role in ovarian cancer remains largely unexplored. In our study, survival analysis of CBP in patients with ovarian cancer was conducted using the Kaplan-Meier Plotter database, then we utilized specific shRNA targeting CREBBP to block the expression of CBP, and detected its effect on cell proliferation and chemo-sensitivity in ovarian cancer cells. The results showed that high expression of CBP was correlated with poor prognosis in ovarian cancer patients. CREBBP knockdown in ovarian cancer cells significantly inhibited tumor proliferation both in vitro and in vivo. Moreover, CREBBP knockdown promoted chemo-sensitivity in ovarian cancer cells. Mechanism research further demonstrated that CREBBP knockdown attenuated unfolded protein response (UPR), which was mediated by PERK/ATF4/STC2 signaling pathway. Our research linked CBP and UPR in ovarian cancer and may provide new strategies for the clinical treatment of ovarian cancer.

Bismuth telluride alloys have dominated the industrial application of thermoelectric cooling, but the relatively poor mechanical performance of commercial zone-melting material seriously limits the device integration and stability. Here, we exhibit synergistically enhanced thermoelectric and mechanical performances of sintered Bi0.48Sb1.52Te3-AgSbSe2 composites. It is found that the increased hole concentration improves the S2σ to 40 μW cm-1 K-2 at room temperature, and the emerged various defects effectively suppress the κl to 0.57 W m-1 K-1 at 350 K. All effects harvest a highest ZT = 1.2 at 350 K along with an average ZT = 1.0 between 300-500 K in the x = 0.2 sample. Notably, AgSbSe2 addition not only optimizes the thermoelectric properties, but also enhances the mechanical performance with a Vickers hardness of 0.75 GPa. Furthermore, the isotropy of thermoelectric properties is also observably promoted by solid-phase reaction combined with high-energy ball milling and hot pressing. Our study reveals a viable strategy to improve the comprehensive performance of sintered bismuth telluride materials.

Bismuth telluride has been the only commercial thermoelectric candidate, but the n-type sintered material lags well behind the p-type one in the zT value, which severely limits the further development of thermoelectrics. Here, we report a promising technique named hot-stacked deformation to effectively improve the thermoelectric properties of n-type Bi2Te2.79Se0.21 + 0.067 wt % BiCl3 materials based on zone-melting ingots. It is found that a high grain alignment is maintained during the plastic deformation and the carrier concentration is properly optimized owing to the donor-like effect, leading to an enhanced power factor. Moreover, the lattice thermal conductivity is obviously suppressed due to the emerged phonon scattering centers of dense grain boundaries and dislocations. These effects synergistically yield a maximum zT value of 1.38 and an average zTave of 1.18 between 300 and 500 K in the hot-stacked deformed sample, which is approximately 42% higher than those of the zone-melting ingots.

Bismuth telluride alloys are the only commercialized thermoelectric materials, which have successfully realized the practical applications of active cooling and waste heat harvesting near room temp...

Dysregulated immune responses have now been recognized as an essential stimulator of ulcerative colitis (UC). Neutrophil extracellular traps (NET) were reported as the potential factor in sustaining mucosal inflammation in UC. NET formation further induces antineutrophil cytoplasm autoantibodies (ANCA) that serve as a biomarker in determining the severity of UC, which have a long half-life due to neonatal Fc receptor (FcRn)-mediated recycling. This study aimed to explore the role of the ANCA-NET cycle in UC and evaluate the potential of targeting FcRn in UC treatment. Dextran sodium sulfate-induced mice and rat models were used in this study. anti-rat FcRn monoclonal antibodies were used to block FcRn function in vivo. Disease activity index (DAI) and histopathological score (HS) were estimated to characterize the inflammation severity of UC. Serum concentrations of IgG, ANCA, TNF-α, IL-1β and CRP were measured using specific ELISA kits. Colonic NET-associated protein (NAP) expression was determined by western blotting. Serum ANCA and colonic NAPs showed a positive correlation that varied with changes in serum inflammation-related indexes (IRI; including TNF-α, IL-1β, and CRP) and DAI and HS in mice with UC. Blockade of FcRn significantly reduced serum ANCA levels and colonic NAP expression and effectively decreased serum IRIs, DAI, and HS in rats with UC. Especially during the inflammation recurrence period, blockade of FcRn exerted even better therapeutic effects in rats with UC than salazosulfapyridine. Our results show that anti-FcRn therapy has benefits in UC treatment through reduced colonic NET formation by accelerating serum ANCA clearance.

Seebeck coefficient describes the temperature gradient induced voltage in thermoelectrics. Usually, to obtain a high Seebeck coefficient within a wide temperature range is difficult, as it is limited by the Goldsmid-Sharp relationship. In this work, the thermoelectric performance of PbSe-AgSbSe2 alloy is optimized by SbCl3 doping. Interestingly, the observed Seebeck coefficient hardly varies as temperature increases from 300 K to 830 K, and its absolute value is at a high level more than 250 μV K-1. By measuring the Hall effect, the anomalous Seebeck coefficient is attributed to the strongly temperature-dependent carrier concentration, which increases from 0.38 × 1019 cm-3 at 300 K to 3.91 × 1019 cm-3 at 830 K. Besides the high Seebeck coefficient, the alloyed compounds exhibit the very low thermal conductivity down to 0.59 W·m-1K-1 at 830 K. Finally, a peak ZT reaches 1.12 at 830 K. It is predicted that the performance of alloys could be further improved by enhancing the carrier concentration.

Retrosynthetic analysis is a canonical technique for planning the synthesis route of organic molecules in drug discovery and development. In this technique, the screening of synthetic tree branches requires accurate forward reaction prediction, but existing software is far from completing this step independently. Previous studies attempted to apply a neural network to forward reaction prediction, but the accuracy was not satisfying. Through using the Edit Vector-based description and extended-connectivity fingerprints to transform the reaction into a vector, this study focuses on the update of the neural network to improve the template-based forward reaction prediction. Hard-threshold activation and the target propagation algorithm are implemented by introducing mixed convex-combinatorial optimization. Comparative tests were conducted to explore the optimal hyperparameter set. Using 15,000 experimental reaction data extracted from granted United States patents, the proposed hard-threshold neural network was systematically trained and tested. The results demonstrated that a higher prediction accuracy was obtained than that for the traditional neural network with backpropagation algorithm. Some successfully predicted reaction examples are also briefly illustrated.

Thermoelectric generator (TEG) has important applications in automotive exhaust waste heat recovery. The Back propagation neural network (BP) can predict the electrical generating performance of TEG efficiently and accurately due to its advantage of being good at handing nonlinear data. However, BP algorithm is easy to fall into local optimum, and its training data usually have deviation since the data are obtained through the simulation software. Both of the problems will reduce the prediction accuracy. In order to further improve the prediction accuracy of BP algorithm, we use the genetic algorithm (GA) to optimize BP neural network by selection, crossover, and mutation operation. Meanwhile, we create a TEG for the heat waste recovery of automotive exhaust and test 84 groups of experimental data set to train the GA−BP prediction model to avoid the deviation caused by the simulation software. The results show that the prediction accuracy of the GA−BP model is better than that of the BP model. For the predicted values of output power and output voltage, the mean absolute percentage error (MAPE) increased to 2.83% and 2.28%, respectively, and the mean square error (MSE) is much smaller than the value before optimization, and the correlation coefficient (R2) of the network model is greater than 0.99.

Zone-melted Bi

Pharmaceutical excipients (PEs) are substances included in drug formulations. Recent studies have revealed that some PEs can affect the activity of metabolic enzymes and drug transporters, however, the effects of PEs on CYP2C8 and its interaction potential with drugs remain unclear. In this study, we evaluated the effects of Tween 80 and EL−35 on CYP2C8 in vitro and further investigated their impacts on the PK of paclitaxel (PTX) in rats after single or multiple doses. The in vitro study indicated that Tween 80 and EL−35 inhibited CYP2C8 activity in human and rat liver microsomes. EL−35 also decreased the expression of CYP2C8 in HepG2 cells. In the in vivo study, Tween 80 did not alter the PK of PTX after single or multiple doses, whereas EL−35 administered for 14 days significantly increased the AUC and MRT of PTX. Further analysis indicated that multiple-dose EL−35 reduced the expression of Cyp2c22 and production of 6-OH-PTX in the rat liver. Our study suggested that short-term exposure to both PEs did not affect the PK of PTX in rats, but multiple doses of EL−35 increased the AUC and MRT of PTX by downregulating the hepatic expression of Cyp2c22. Such effects should be taken into consideration during drug formulation and administration.

The layered chalcogenide SnSe has attracted great interest for its remarkable ZT records. Here, we report the excellent thermoelectric performance of n-type SnSe single crystals by alloying with PbBr2, where a maximum ZT of 2.1 at 770 K is achieved along the out-of-plane direction. Interestingly, we observed a sharp drop of the carrier mobility at PbBr2 content x = 3%, which terminates the continuous increase of ZT from x = 0.5% to x = 2%. It is shown that the anomalous decrease is due to the evolution of the Fermi surface driven by the enlargement of the out-of-plane axis. When 1% Sn is substituted by Ge, the restoration of the Fermi surface increases the ZT for the x = 3% sample by 200%. This study reveals the crucial role of the Fermi-surface dynamics in n-type SnSe, and the consequent strategy is confirmed to be highly efficient in the optimization of thermoelectric performance.

As an attractive lead-free thermoelectric candidate, GeTe-based materials have been intensively studied in recent years. However, the ZT value of pristine GeTe is limited around unit owing to the excessive hole concentration by intrinsic Ge vacancies. In this work, we report the synergistic enhancement of thermoelectric properties in rhombohedral GeTe by Bi–Zn codoping. It is found that Bi doping can effectively optimize the carrier concentration. Density functional calculations demonstrated that both Zn doping and the reduced c/a ratio by Bi doping could promote valence band convergence and Seebeck coefficient enhancement. Furthermore, lattice thermal conductivity is also significantly suppressed due to the Bi–Zn codoping introduced phonon scattering centers including point defects, Ge nano-precipitates, herringbone domains, twin boundaries, concentrated stress and density dislocations in the matrix. Consequently, a peak ZT of 2.0 at 700 K and a ZTave of 1.35 from 400 to 800 K are realized in Ge0.9Bi0.06Zn0.04Te.

Tin selenide (SnSe) is a promising thermoelectric material because of its advantageous electronic structure and low thermal conductivity. In this work, n-type polycrystalline SnSe0.95 doped with a new dopant NbCl5 was prepared using vacuum melting and hot-pressing (HP) methods, which resulted in a textured microstructure and anisotropic thermoelectric performance. Several state-of-the-art characterization studies via XRD, SEM, and XPS were conducted to analyze the crystal phase, microstructure, and composition of the samples. The TEM observation showed that large amounts of dislocations and nanocrystalline grains existed in our polycrystalline SnSe0.95, which resulted in lower thermal conductivity and better mechanical performance compared to previous reports. The electrical transport measurements along the parallel and perpendicular directions to the HP pressure revealed that the scattering behavior of charge carriers was complex and had a profound effect on the overall thermoelectric properties. Finally, a maximum ZT value of 1.22 at 790 K was attained in the 0.5% NbCl5-doped SnSe0.95 sample, which exceeds most of the n-type polycrystalline SnSe systems doped with other halides.

Bismuth telluride alloys have dominated the industrial application of thermoelectric cooling, but the relatively poor mechanical performance of commercial zone-melting material seriously limits the device integration and stability. Here, we exhibit synergistically enhanced thermoelectric and mechanical performances of sintered Bi

Bismuth telluride has been the only commercial thermoelectric candidate, but the n-type sintered material lags well behind the p-type one in the

Phonon engineering is a core stratagem to improve the thermoelectric performance, and multi-scale defects are expected to scatter a broad range of phonons and compress the lattice thermal conductivity. Here, we demonstrate obviously enhanced thermoelectric properties in Bi0.48Sb1.52Te3 alloy by a hot-pressing texture method along the axial direction of a zone-melted ingot. It is found that a plastic deformation of grain refinement and rearrangement occurs during the textured pressing process. Although the obtained power factor is slightly decreased, a large amount of grain boundaries emerges in the textured samples and dense dislocations are observed around the boundaries and inside the grains. These additional phonon scattering centers can effectively scatter the low- and mid-frequency phonons, and the corresponding lattice thermal conductivity is significantly reduced to only 50% of that of zone-melted samples. Consequently, the maximum figure of merit (ZT) reaches 1.44 at 330 K and the average ZT (300-380 K) reaches 1.38. This study suggests that the simple hot-pressing texture technique is a promising method to significantly optimize the cooling capacity of Bi0.48Sb1.52Te3-based thermoelectric refrigeration.

Recently, Mg3Sb2 attracted much research interest due to its competitive thermoelectric performance of ZT = 1.7 observed in n-type materials at 700 K. On the other hand, the thermoelectric performance of p-type Mg3Sb2 is found to be limited (ZT < 0.7) by the low power factor, originating in the less degenerate valence valleys. In this paper, we report a systematic theoretic investigation on the thermoelectric properties of Mg3Sb2 by using band structure and transport calculations. Starting with the careful analysis of the band structure, the characteristics of the valence and conduction bands are clarified. By raising the concept of crystal field screening, a scheme to increase the degeneracy of valence valleys is proposed. The expected band convergence is numerically confirmed in Ba-doped p-type Mg3Sb2, where a significantly improved ZT = 1.2 at 800 K is predicted. This study provides an applicable scheme for improving the thermoelectric performance of Mg3Sb2, and also it enriches the concept of band engineering for thermoelectrics.

Band engineering is an important experimental approach to increase the thermopower of thermoelectric materials, whereas the underlying mechanism has been barely clarified. In PbTe and SnTe, the effective dopants for band engineering, such as Sr, Mn, Cd, and Eu, seem to be randomly distributed on the periodic table. By constructing an analysis model from density functional calculations, the varied experimental observations are arranged into a unified phase diagram as a function of a single variable: the s orbital energy level. Consequently, several neglected effective dopants in previous studies are naturally identified. The analysis method is further applied to GeTe and GeSe, and two kinds of band engineering are theoretically suggested. In this study, the proposed method for electronic structure analysis enables us to design the band engineering directly from the periodic table, which we hope will encourage and accelerate more experimental and theoretical research studies in the thermoelectric field.

Polycrystalline Sn1−xCuxSe samples have been prepared using hot pressing to study the Cu doping effect on carrier concentration in SnSe. Different from Ag, Cu doping decreases the carrier concentration of SnSe at room temperature. The carrier concentration of Cu doped samples increases obviously with temperature, becomes larger than the pristine sample above 523 K, and approaches the values of Na doped SnSe at 773 K. The enhanced carrier concentration leads to better electrical conductivity, resulting in higher power factors at high temperatures. Due to carrier optimization by Cu, a peak ZT of 0.66 is achieved in Sn0.98Cu0.02Se at 813 K.