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Prostate cancer (PCa) is an age-related malignancy with a high incidence and mortality rate due to lack of efficacy drugs for its therapy in late castration-resistant stage. Sirtuin 2 (SIRT2), a NADData of SIRT2 expression were extracted from TCGA cohort and GSE54460 cohort. Realtime quantitative PCR and immunohistochemistry were employed to analyze the expression of SIRT2 in PCa tissues. Cell counting Kit-8 assay, lentiviral transduction, flow cytometry, transwell experiments, western blot and metabolomic analysis were performed to explore the functions of SIRT2.SIRT2 exhibited increased expression in castration-resistant prostate cancer (CRPC) and neuroendocrine prostate cancer (NEPC). Overexpression of SIRT2 promoted cell proliferation, the proportion of S phase, migration and invasion, and reduced apoptosis rate. The increased phosphorylated ERK1/2 indicated the regulation of SIRT2 to cell proliferation, migration and invasion through activation of ERK1/2 pathway. Furthermore, SIRT2 affected cell metabolic profile and induces lactosylceramide production through upregulation of B4GALT5, which further contributes cell migration and invasion.Our data suggested that SIRT2 is overexpressed in CRPC and NEPC and could promote cell growth and migration through activating ERK1/2 pathway and inducing lactosylceramide production, indicating that SIRT2 has the potential to be a new target for the treatment of PCa.

Background Several studies have shown that social security would reduce health inequalities. However, little was known about the relationship between long-term care insurance and health inequality. We aimed to evaluate the impact of long-term care insurance on health status and health inequality in older adults using a nationally representative cohort. Methods Based on four waves of data from the China Health and Retirement Longitudinal Study (CHARLS 2011, 2013, 2015 and 2018), we used the staggered difference in difference (DID) design with the order probit regression models and the concentration index approach as well as decomposition analysis to assess the contribution of long-term care insurance towards residents’ health status and health inequality in older adults aged ≥65 y. We further used the semi-parametric DID model for robustness testing. Results Long-term care insurance demonstrated its role, improving self-assessed health in the study population (βcoefficient: 0.090, 95% CI 0.087 to 0.092, p Conclusions The findings implied that long-term care insurance has widened the health inequality while improving health status in older adults. Additional investment in more comprehensive insurance coverage and increased accessibility to enhance implementation of long-term care insurance is warranted to close the gap.

Objective Opioid-sparing anesthesia reduces intraoperative use of opioids and reduced adverse postoperative events. The present study investigated the effect of esketamine-based opioid-sparing anesthesia on total laparoscopic hysterectomy patients' recovery. Methods Ninety patients undergoing total laparoscopic hysterectomy were randomly assigned to esketamine-based group (group K) or opioid-based group (group C). Patients, surgeons, and postoperative medical staff were blinded to group allocation. Due to the different drug administration protocols by groups, the anesthesiologist couldn't be blinded. The QoR-40 and VAS were used to measure recovery quality. Postoperative adverse events, perioperative opioid consumption, and intraoperative hemodynamics were secondary endpoints. Results The patients in both groups had comparable baseline characteristics. QoR-40 scores were higher in group K than in group C on postoperative day 1(160.91 ± 9.11 vs 151.47 ± 8.35, respectively; mean difference 9.44 [95%CI: 5.78–13.11]; P P P P

Background Knowing the spatiotemporal pattern of the early geographic spread of coronavirus disease 2019 (COVID-19) would inform the preparedness for a possible recurrence of COVID-19. Methods We ascertained the number of confirmed cases during the early spread of COVID-19 during the Wuhan outbreak in 2020 and the Nanjing outbreak in 2021. Results We observed a speeding-up pattern of geographic spread, in particular to cities of no particular orientation then outflowing to commercial cities during the first month of both the Wuhan and Nanjing outbreaks. Conclusion Re-emergence of COVID-19 indicates it is becoming endemic, with new outbreaks and a risk of increased transmission remaining a challenge to local public health institutions. Social distancing and lockdowns should continue in response to any potential widespread and focal outbreaks.

Histone methylation, as an essential pattern of posttranslational modifications, contributes to multiple cancer-related biological processes. Dysregulation of histone methylation is now considered a biomarker for cancer prognosis. This study investigated and evaluated the potential role of four histone lysine trimethylation markers as biomarkers for esophageal squamous cell carcinoma (ESCC) prognosis. Tissue arrays were made from 135 paraffin-embedded ESCC samples and examined for histone markers by immunohistochemistry, and 10 pairs of cancer and noncancerous mucosa tissues from ESCC patients were investigated with Western blot. Chi-squared test, Kaplan–Meier analysis with log-rank test, and Cox proportional hazard trend analyses were performed to assess the prognostic values of the markers. Histone 3 lysine 4 trimethylation (H3K4me3), histone 3 lysine 9 trimethylation (H3K9me3), and histone 4 lysine 20 trimethylation (H4K20me3), but not histone 3 lysine 36 trimethylation (H3K36me3), showed stronger immunostaining signals in tumor tissues than in the corresponding adjacent non-neoplastic mucosa tissues. The expression patterns of H3K36me3, H3K9me3, and H4K20me3 correlated with tumor infiltrating depth, lymph node involvement, and pTNM stage. Low-scoring H3K9me3 and H4K20me3 predicted better prognosis, while H3K36me3 manifested the opposite trend. Poor prognosis occurred in ESCC patients with expression patterns of high levels of H3K9me3, high levels of H4K20me3, and low levels of H3K36me3 expression. H3K9me3, H4K20me3, and H3K36me3 showed a close relationship with clinical features and were considered independent risk factors for survival of ESCC patients. The combination of H3K9me3, H4K20me3, and H3K36me3 expression, rather than the expression of a single histone marker, is believed to further enhance evaluations of ESCC prognosis and management.

Aim: To investigate hypoxia-inducible factor-1α (HIF-1α) and histone methylation markers as potential indicators of prognosis in esophageal squamous cell carcinoma (ESCC). Patients & methods: The prognostic value of HIF-1α and histone methylation markers levels was analyzed using Kaplan–Meier survival analysis. Results: HIF-1α protein expression was higher in ESCC tumors than in paracancerous tissues. Histone H3 Lys9 trimethylation (H3K9me3), histone H3 Lys27 trimethylation (H3K27me3), histone H3 Lys4 trimethylation (H3K4me3) and histone H4 Lys20 trimethylation (H4K20me3) were significantly upregulated in ESCC tissues. HIF-1α was only positively correlated with H3K9me3 and H3K4me3 expression. Kaplan–Meier analysis indicated that H3K9me3, H3K27me3, H4K20me3 and histone H3 Lys36 trimethylation (H3K36me3) were independent indicators of prognosis for ESCC. Conclusion: This study identified a pattern of epigenetic methylation markers and HIF-1α expression in ESCC, and their combined evaluation might improve survival prediction for ESCC patients.

While several functional and structural changes occur in large-scale brain networks in autism spectrum disorder (ASD), reduced interhemispheric resting-state functional connectivity (rsFC) between homotopic regions may be of particular importance as a biomarker. ASD is an early-onset developmental disorder and neural alterations are often age-dependent. Although there is some evidence for homotopic interhemispheric rsFC alterations in language processing regions in ASD children, wider analyses using large data sets have not been performed. The present study, therefore, conducted a voxel-based homotopic interhemispheric rsFC analysis in 146 ASD and 175 typically developing children under-age 10 and examined associations with symptom severity in the autism brain imaging data exchange data sets. Given the role of corpus callosum (CC) in interhemispheric connectivity and reported CC volume changes in ASD we additionally examined whether there were parallel volumetric changes. Results demonstrated decreased homotopic rsFC in ASD children in the posterior cingulate cortex (PCC) and precuneus of the default mode network, the precentral gyrus of the mirror neuron system, and the caudate of the reward system. Homotopic rsFC of the PCC was associated with symptom severity. Furthermore, although no significant CC volume changes were found in ASD children, there was a significant negative correlation between the anterior CC volumes and homotopic rsFC strengths in the caudate. The present study shows that a reduced pattern of homotopic interhemispheric rsFC in ASD adults/adolescents is already present in children of 5-10 years old and further supports their potential use as a general ASD biomarker. LAY SUMMARY: Homotopic interhemispheric functional connectivity plays an important role in synchronizing activity between the two hemispheres and is altered in adults and adolescents with autism spectrum disorder (ASD). In the present study focused on children with ASD, we have observed a similar pattern of decreased homotopic connectivity, suggesting that alterations in homotopic interhemispheric connectivity may occur early in ASD and be a useful general biomarker across ages.

Increasing studies showed that long-noncoding RNAs (lncRNAs) play important roles in the biological processes, including cancer initiation and progression. However, little is known about the exact role and regulation mechanism of lncRNA UCA1 during the progression of gastric cancer (GC). In this study, we found that UCA1 was aberrantly elevated in gastric cancer tissues, and was significantly associated with lymph node metastasis and TNM stage. In vivo and in vitro, enforced UCA1 level promoted cell migration and invasion of GC cell. Depleted UCA1 expression level attenuated the ability of cell migration and invasion in GC. And then, we detected that expression level of ZEB2, a transcription factor related to tumor metastasis, was regulated by UCA1 in GC cells. miR-203 targets and suppresses to ZEB2 expression. Furthermore, we found that UCA1 could directly interact with miR-203 and lead to the release of miR-203-targeted transcripts ZEB2. Herein, we revealed the novel mechanism of UCA1 on regulating metastasis-related gene by sponge regulatory axis during GC metastasis. Our findings indicated that UCA1 plays a critical role in metastatic GC by mediating sponge regulatory axis miR-203/ZEB2. To explore function of UCA1-miR-203-ZEB2 axis may provide an informative biomarker of malignancy and a highly selective anti-GC therapeutic target.

Long noncoding RNA (lncRNA) has been implicated in cancer, but little is known about the role of lncRNAs as regulators of tumor metastasis. In the present study, we demonstrate that lncRNA TRERNA1 acts like an enhancer of SNAI1 to promote cell invasion and migration and to contribute to metastasis of gastric cancer (GC). TRERNA1 is significantly unregulated in GCs and GC cell lines. Increased TRERNA1 is positively correlated with lymph node metastasis of GCs. RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP) assays revealed that TRERNA1 functions as a scaffold to recruit EZH2 to epigenetically silence epithelial-mesenchymal transition marker CDH1 by H3K27me3 of its promoter region. TRERNA1 knockdown markedly reduced GC cell migration, invasion, tumorigenicity, and metastasis. Depletion of TRERNA1 reduced cell metastasis of GCs in vivo. Taken together, our findings indicated that TRERNA1 serves as a critical effector in GC progression by regulating CDH1 at the transcription level. It is implied that TRERNA1/CDH1 is a new potential target for GC therapy. Keywords: TRERNA1, SNAI1, metastasis, gastric cancer, CDH1

Occlusion relationship reasoning demands closed contour to express the object, and orientation of each contour pixel to describe the order relationship between objects. Current CNN-based methods neglect two critical issues of the task: (1) simultaneous existence of the relevance and distinction for the two elements, i.e, occlusion edge and occlusion orientation; and (2) inadequate exploration to the orientation features. For the reasons above, we propose the Occlusion-shared and Feature-separated Network (OFNet). On one hand, considering the relevance between edge and orientation, two sub-networks are designed to share the occlusion cue. On the other hand, the whole network is split into two paths to learn the high-level semantic features separately. Moreover, a contextual feature for orientation prediction is extracted, which represents the bilateral cue of the foreground and background areas. The bilateral cue is then fused with the occlusion cue to precisely locate the object regions. Finally, a stripe convolution is designed to further aggregate features from surrounding scenes of the occlusion edge. The proposed OFNet remarkably advances the state-of-the-art approaches on PIOD and BSDS ownership dataset. The source code is available at https://github.com/buptlr/OFNet., Comment: Accepted by ICCV 2019. Code and pretrained model are available at https://github.com/buptlr/OFNet

Background: Esophageal cancer (EC) is the fourth most commonly diagnosed cancer in males and the fifth in females in China. Dysregulation methylation of histone is now considered a biomarker for cancer prognosis. Methods: In this study, we focused on exploring the expression patterns of two repressor histone methylation marks, H3K9 dimethylation (H3K9me2) and H3K27 trimethylation (H3K27me3), to provide potential biomarkers for diagnosis and therapies in esophageal squamous cell carcinoma (ESCC). Results: After analyzing the relationship between the expression pattern of H3K27me3 and the clinic-pathological features of ESCC tissues, we found that upregulated H3K27me3 correlated with advanced T stage and N stage. A multivariate Cox regression analysis showed H3K27me3 expression, T stage and N stage were all independent factors for the poor prognosis of ESCC. Therefore, H3K27me3 can be considered an independent factor for predicting the prognosis of ESCC. Conclusions: Chromatin remodeling, especially the methylation of H3, plays a vital role in ESCC development and is a potential therapeutic target.

For tiny obstacle discovery in a monocular image, edge is a fundamental visual element. Nevertheless, because of various reasons, e.g., noise and similar color distribution with background, it is still difficult to detect the edges of tiny obstacles at long distance. In this paper, we propose an obstacle-aware discovery method to recover the missing contours of these obstacles, which helps to obtain obstacle proposals as much as possible. First, by using visual cues in monocular images, several multi-layer regions are elaborately inferred to reveal the distances from the camera. Second, several novel obstacle-aware occlusion edge maps are constructed to well capture the contours of tiny obstacles, which combines cues from each layer. Third, to ensure the existence of the tiny obstacle proposals, the maps from all layers are used for proposals extraction. Finally, based on these proposals containing tiny obstacles, a novel obstacle-aware regressor is proposed to generate an obstacle occupied probability map with high confidence. The convincing experimental results with comparisons on the Lost and Found dataset demonstrate the effectiveness of our approach, achieving around 9.5% improvement on the accuracy than FPHT and PHT, it even gets comparable performance to MergeNet. Moreover, our method outperforms the state-of-the-art algorithms and significantly improves the discovery ability for tiny obstacles at long distance., Accepted to 2019 International Conference on Robotics and Automation (ICRA)

A core challenge of thermoelectric research is decoupling the otherwise inversely interdependent properties electrical conductivity, thermopower, and lattice thermal conductivity offering synergistic effects. Herein, we present a systematic study in which we have substituted Lanthanum into the Zn-site in β-Zn4Sb3 compound. We observed that La-substitution not only simultaneously enhances electrical conductivity and thermopower over a wide temperature range but also substantially reduces the lattice thermal conductivity. These synergistic effects of La-substitution are discussed in terms of the substitution-induced variation in carrier concentration and effective mass as well as stronger phonon scattering by point defects. As a result, a ∼30% increase of the power factor and a ∼23% reduction in the lattice thermal conductivity led to a state-of-the-art ZT ∼1.3 at 648 K for the bulk sample of β-La0.01Zn3.99Sb3.

Compositing is proven to be effective in enhancing thermoelectric performance. The present paper illustrates the thermoelectric study of CoSb3–yWTe2 meso-composites between 300 K and 575 K, where y denotes the weight percentage of WTe2 (y = 0, 3, 6, 9 and 12). Micro-sized WTe2 grains were randomly embedded in the nano-sized unfilled CoSb3 host matrix. We found that the electrical conductivity of CoSb3–yWTe2 composites was markedly increased in a systematic trend with increasing WTe2 content. The enhancement of the electrical conductivity has been attributed to the locally percolated highly conductive WTe2 pellets along with better electrical connections between grains as a result of increased packing density. Meanwhile, the pronounced bipolar peak of pristine CoSb3 was quickly suppressed upon the addition of WTe2. The n-type thermopower of CoSb3–yWTe2 composites became nearly linear between 300 K and 575 K, and the magnitude of thermopower decreased with increasing WTe2 content. The power factor is markedly enhanced up to 59 times that of the pristine CoSb3 upon compositing. The dimensionless thermoelectric figure-of-merit zT value of 0.78 is attained at 575 K, which promises practical applications for the unfilled CoSb3 composites.

No thermoelectric material would have attained its best performance without defects. The electrical resistivity, Seebeck coefficient, and thermal conductivity in their totality are manifestations of charge flow, phonon flow, and their interplay mediated by defects. We herein focus on the role of 0-D defects (dopants, vacancies, interstitials, and antisites), 1-D defects (dislocations), 2-D defects (grain boundaries), and 3-D defects (nanoinclusions) in a benchmark thermoelectric material Bi2Te3. The results give new insights into developing higher performance thermoelectric materials via defect engineering.

The thermal properties of yttrium-stabilized lithium zirconate phosphate [LZP: Li1+x+yYxZr2−x(PO4)3 with x = 0.15, −0.2 ≤ y ≤ 0.4 and with x = 0.0, y = 0.0] are presented over a wide temperature range from 30 to 973 K, elucidating the interplay between structural phase transformations and thermal properties in a solid state superionic conducting material. At room temperature, the thermal conductivity decreases by more than 75% as the stoichiometry is changed from lithium deficient to excess and increases with increasing temperature, indicative of defect-mediated transport in the spark plasma sintered materials. The phase transformations and their stabilities are examined by x-ray diffraction and differential scanning calorimetry and indicate that the Y3+ substitution of Zr4+ is effective in stabilizing the ionically conductive rhombohedral phase over the entire temperature range measured, the mechanism of which is found through ab initio theoretical calculations. These insights into thermal transport of LZP superionic conductors are valuable as they may be generally applicable for predicting material stability and thermal management in the ceramic electrolyte of future all-solid-state-battery devices.

The thermoelectric properties of spark plasma sintered, ball-milled, p-type Si80Ge20-(NaBH4)x (x = 0.7,1.7 and 2.7), and Si80Ge20B1.7-y-(NaBH4)y (y = 0.2 and 0.7) samples have been investigated from 30 K to 1100 K. These samples were prepared by spark plasma sintering of an admixture of Si, Ge, B and NaBH4 powders. In particular, the degasing process during the spark plasma sintering process, the combined results of X-ray powder diffraction, Raman spectroscopy, Hall coefficient, electrical resistivity, and Seebeck coefficient measurements indicated that NaBH4 decomposed into Na, B, Na2B29, and H2 during the spark plasma sintering process, Na and B were doped into the SiGe lattice, resulting in favorable changes in the carrier concentration and the power factor. In addition, the ball milling process and the formation of Na2B29 nanoparticles resulted in stronger grain boundary scattering of heat-carrying phonons, leading to a reduced lattice thermal conductivity. As a result, a significant improvement in the figure of merit ZT (60%) was attained in p-type Si80Ge20-(NaBH4)1.7 and Si80Ge20-B1.5(NaBH4)0.7 at 1100 K as compared to the p-type B-doped Si80Ge20 material used in the NASA’s radioactive thermoelectric generators. This single-step “doping-nanostructuring” procedure can possibly be applied to other thermoelectric materials.

Cancer cell invasion and metastasis are the leading causes of the high mortality rates in patients with malignant tumors. There is accumulating evidence to indicate that dysregulated long non‑coding RNAs (lncRNAs) may be involved in the progression of tumor invasion and metastasis. However, the regulatory mechanisms of the aberrant expression of lncRNAs remain largely unknown, although the roles of lncRNAs as drivers of tumor suppressive and oncogenic functions have appeared in prevalent cancer types in recent years. In the present study, we identified that the transcription factor, activating enhancer‑binding protein 4 (TFAP4), acts as a key modulator of translation regulatory long non‑coding RNA 1(TRERNA1), which has been proven to promote the invasion and metastasis of gastric cancer (GC) cells. We revealed that TRERNA1 was upregulated in gastric carcinogenesis and promoted cell migration and invasion in GC. Using bioinformatics analysis, we observed that there were several potential binding sites of TFAP4 in the promoter region of TRERNA1. The knockdown of TFAP4 significantly reduced the expression level of TRERNA1, whereas the ectopic expression of TFAP4 significantly increased the expression level of TRERNA1 in GC cell lines. Dual luciferase reporter assay combined with chromatin immunoprecipitation (ChIP) revealed that TFAP4 specifically regulated the transcriptional activity of TRERNA1 by binding to the E‑box motifs in the TRERNA1 promoter. In addition, there was a positive correlation between the TFAP4 and TRERNA1 expression level in clinical GC cases, which also indicated that TFAP4 can directly modulate the expression of TRERNA1. In the present study, we provide a novel potential therapeutic target and strategy for GC.

Over the past decade, the open frame (``cagey'') structure of $\mathrm{CoS}{\mathrm{b}}_{3}$ skutterudite has invited intensive filling studies with various rare-earth elements for delivering state-of-the-art midtemperature thermoelectric performance. To rationalize previously reported experimental results and provide new insight into the underexplored roles of La fillers and Sb vacancies, ab initio density functional theory studies, along with semiclassical Boltzmann transport theory calculations, are performed for pristine $\mathrm{CoS}{\mathrm{b}}_{3}$ of different lattice settings and La-filled $\mathrm{CoS}{\mathrm{b}}_{3}$ with and without Sb's mono- and divacancy defects. The effects of spin-orbit coupling (SOC), partial La filling, Sb vacancy defects, and spin polarization on the electronic and thermoelectric properties are systematically examined. The SOC shows minor effects on the electronic and thermoelectric properties of $\mathrm{CoS}{\mathrm{b}}_{3}$. The peculiar quasi-Dirac band in the pristine $\mathrm{CoS}{\mathrm{b}}_{3}$ largely survives La filling but not Sb vacancies, which instead introduce dispersive bands in the band gap region. The non-spin-polarized and spin-polarized solutions of La-filled $\mathrm{CoS}{\mathrm{b}}_{3}$ are nearly degenerate. Importantly, the band structure, density of states, and Fermi surface of the latter are significantly spin polarized, giving rise to spin-dependent thermoelectric properties. Seebeck coefficients directly calculated as a function of chemical potential are interpreted in connection with the electronic structures. Temperature-dependent Seebeck coefficients derived for the experimentally studied materials agree well with available experimental data. Seebeck coefficients obtained as a function of charge carrier concentration corroborate the thermoelectrically favorable role at high filling fractions played by the Fermi electron pockets associated with the degenerate valleys in the conduction bands, and also point toward a similar role of the Fermi hole pockets associated with the degenerate hills in the valence bands. These results serve to advance the understanding of $\mathrm{CoS}{\mathrm{b}}_{3}$ skutterudite, a class of materials with important fundamental and application implications for thermoelectrics and spintronics.

The single-filled skutterudite Yb0.2Co4Sb12 has been long known as a promising bulk thermoelectric material. In this work, we adopted a melting–milling–hot pressing procedure to prepare nanocomposites that consist of a micrometer-grained Yb0.2Co4Sb12 matrix and well-dispersed AgSbTe2 nanoinclusions on the matrix grain boundaries. Different weight percentages of AgSbTe2 inclusions were added to optimize the thermoelectric performance. We found that the addition of AgSbTe2 nanoinclusions systematically and simultaneously optimized the otherwise adversely inter-dependent electrical conductivity, Seebeck coefficient and thermal conductivity. In particular, the significantly enhanced carrier mobility led to a ∼3-fold reduction of the electrical resistivity. Meanwhile the absolute value of Seebeck coefficient was enhanced via the energy filtering effect at the matrix–nanoinclusion interfaces. Moreover there is a topological crossover of the AgSbTe2 inclusions from isolated nanoparticles to a nano-plating or nano-coating between 6 wt% and 8 wt% of nanoinclusions. Above the crossover, further addition of nanoinclusions degraded the Seebeck coefficient and the electrical conductivity. Meanwhile, the addition of nanoinclusions generally reduced the lattice thermal conductivity. As a result, the power factor of the 6 wt% sample was ∼7 times larger than that of the nanoinclusion-free sample, yielding a room temperature figure of merit ZT ∼ 0.51.

A series of Ta1+x Se2 (0.00 ≤ x ≤ 0.12) samples was prepared and characterized by x-ray powder diffraction, resistance, magnetization and specific heat measurements. Based on the fitting of the diffraction patterns, we found that Ta1+x Se2 has two randomly stacked structures with distinct stacking units: 2Hb and 3R slabs when x ≤ 0.06 and single TaSe2 layers with Ta atoms in trigonal prismatic coordination with Se when x > 0.06. The superconducting critical temperatures (T c) of the Ta1+x Se2 samples can be significantly enhanced from 0.14 K for pure TaSe2 to above 2 K in the Ta-rich samples with both structures. The maximum T c of 3.2 K was obtained in Ta1.06Se2. The remarkable enhancement of T c in Ta1+x Se2 originates from the enhancement of N(E F) and λ.

In order to investigate the phonon scattering mechanisms in double-filled skutterudites, the low-temperature lattice thermal conductivities of In0.1Yb y Co4Sb12 were measured and analyzed based on the Debye model. The eingenmode frequencies of In and Yb were obtained from low-temperature specific heat capacity analysis. It is found that filling these two types of guest atoms with different eingenmode frequencies into the voids in skutterudites could introduce strong point defect and resonant scattering to lattice phonons, thus lead to significant decrease in the lattice thermal conductivity.

It has been demonstrated that InSb nanoinclusions, which are formed in situ, can simultaneously improve all three individual thermoelectric properties of the n-type half-Heusler compound (Ti,Zr,Hf)(Co,Ni)Sb (Xie WJ, He J, Zhu S, Su XL, Wang SY, Holgate T, et al. Acta Mater 2010;58:4795). In the present work, the same approach is adopted to the p-type half-Heusler compound Ti(Co,Fe)Sb. The results of resistivity, Seebeck coefficient, thermal conductivity and Hall coefficient measurements indicate that the combined high-mobility electron injection, low energy electron filtering and boundary scattering, again, lead to a simultaneous improvement in all three individual thermoelectric properties: enhanced Seebeck coefficient and electrical conductivity as well as reduced lattice thermal conductivity. A figure of merit of ZT ≈ 0.33 was attained at 900 K for the sample containing 1.0 at.% InSb nanoinclusions, a ∼450% improvement over the nanoinclusion-free sample. This represents a rare case that the same nanostructuring approach works successfully for both p-type and n-type thermoelectric materials of the same class, hence pointing to a promising materials design route for higher-performance half-Heusler materials in the future and hopefully will realize similar improvement in thermoelectric devices based on such half-Heusler alloys.

Polycrystalline samples of nickel intercalated (0–5%) TiSe 2 were attempted via solid-state reaction in evacuated quartz tubes followed by densification using a spark plasma sintering process. X-ray diffraction data indicated that mixed NiSe 2 and TiSe 2 phases were present after initial synthesis by solid-state reaction, but a pure TiSe 2 phase was present after the spark plasma sintering. While EPMA data reveals the stoichiometry to be near 1:1.8 (Ti:Se) for all samples, comparisons of the measured bulk densities to the theoretical densities suggest that the off stoichiometry is a result of the co-intercalation of both Ni and Ti rather than Se vacancies. Due to the presence of excess Ti (0.085–0.130 per formula) in the van der Waals gap of all the samples, the sensitive electron–hole balance is offset by the additional Ti-3d electrons, leading to an increase in the thermopower ( n -type) over pristine, stoichiometric TiSe 2 . The effects of the co-intercalation of both Ni and Ti in TiSe 2 on the structural, thermal, and electrical properties are discussed herein.