Conducting polymers are potential candidates for thermoelectric (TE) applications owing to their low thermal conductivity, non-toxicity and low cost. However, the coil conformation and random aggregation of polymer chains usually degrade electrical transport properties, thus deteriorating TE performance. In this work, we fabricated poly(3-hexylthiophene) (P3HT) films with highly oriented morphology using 1,3,5-trichlorobenzene (TCB), an organic small-molecule, as a template for polymer epitaxy under a temperature gradient crystallization process. The resulting P3HT molecules, which were confirmed to be highly anisotropic by a combination of scanning electron microscopy, atomic force microscopy, polarizing microscope, polarized Raman spectroscopy, and two-dimensional-grazing incidence X-ray diffraction (GIXRD) analysis, not only markedly reduced the conjugated defects along the polymer backbone, but also effectively increased the degree of electron delocalization. These combined phenomena produced an efficient, 1D path for carrier movement and therefore resulted in enhanced carrier mobility in the TCB-treated P3HT films. The maximum values of the electrical conductivity and Seebeck coefficient were 320 S cm À1 and 269 μV K À1 , respectively. Consequently, the maximum TE power factor and ZT value at 365 K reached 62.4 μW mK À2 and 0.1, respectively, in the parallel direction of the TCB-treated P3HT film. To the best of our knowledge, these are the highest values reported for pure P3HT TE materials. The method of using organic small-molecule epitaxy to generate highly anisotropic polymer films is expected to be valid for many conducting polymers.

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The formation of pre-metastatic niche is a key step in the metastatic burden. The pluripotent factor Lin28B is frequently expressed in breast tumors and is particularly upregulated in the triple negative breast cancer subtype. Here, we demonstrate that Lin28B promotes lung metastasis of breast cancer by building an immune-suppressive pre-metastatic niche. Lin28B enables neutrophil recruitment and N2 conversion. The N2 neutrophils are then essential for immune suppression in pre-metastatic lung by PD-L2 up-regulation and a dysregulated cytokine milieu. We also identify that breast cancer-released exosomes with low let-7s are a prerequisite for Lin28B-induced immune suppression. Moreover, Lin28B-induced breast cancer stem cells are the main sources of low-let-7s exosomes. Clinical data further verify that high Lin28B and low let-7s in tumors are both indicators for poor prognosis and lung metastasis in breast cancer patients. Together, these data reveal a mechanism by which Lin28B directs the formation of an immune-suppressive pre-metastatic niche.

Background Recently, it has been found that the gut microbiota may affect the development of lung cancer through the “gut‐lung axis.” To investigate this relationship, we performed this study to determine whether the gut microbiota in non‐small‐cell lung cancer (NSCLC) patients is different from that in healthy adults. Methods Quantitative PCR (qPCR) was used to detect the expression levels of eight gut butyrate‐producing bacteria in healthy adults and NSCLC patients. We enrolled 30 patients with NSCLC and 30 subjects from 100 healthy adults after matching for age and sex. Results Compared to healthy adults, most of the gut butyrate‐producing bacteria in NSCLC patients were significantly decreased; these included Faecalibacterium prausnitzii , Clostridium leptum , Clostridial cluster I , Ruminococcus spp., Clostridial Cluster XIVa , and Roseburia spp. Among the gut butyrate‐producing bacteria, we analyzed Clostridial cluster IV and Eubacterium rectale were not decreased in NSCLC patients. Conclusions We conclude that NSCLC patients had gut butyrate‐producing bacteria dysbiosis. Further studies should be performed to investigate the underlying mechanisms of how these specific bacteria affect lung cancer progression and prognosis.

The presence of whale sharks Rhincodon typus were recorded around Shib Habil, a small, coastal reef off the Red Sea coast of Saudi Arabia, from 2010 to 2015. A total of 267 suitable photographs resulting in the identification of 136 individuals, were documented from 305 encounters. Sharks were divided evenly between the sexes with no evidence of temporal or spatial segregation. All individuals were immature based on size estimates and, for males, juvenile clasper morphology. Scars were reported for 57% of R. typus with 15% showing evidence of propeller trauma. Estimates of population size and patterns of residency were calculated by modelling the lagged identification rate. Multiple models were run simultaneously and compared using the Akaike information criterion. An open population model was found to best represent the data and estimates a daily abundance between 15 and 34 R. typus during the aggregation season, with local residence times ranging from 4 to 44 days. Residence times away from Shib Habil range from 15 to 156 days with a permanent emigration-death rate between 0·07 and 0·58 individuals year(-1) . These results are broadly similar to those from other aggregations of R. typus, although the observed sexual parity and integration found at this site is unique for the species and needs further study.

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Advances in metal–organic frameworks (MOFs) are stimulating interest in water‐evaporation induced electricity generation. Establishing design principles for desirable MOFs and revealing the structure‐activity relationship is essential to development of this field. Around this key issue, herein the concept of “hierarchical oriented MOFs” is proposed and the Cu(BDC‐OH) MOFs are organized into hierarchical oriented assemblies by successively using methods of hydrolysis, anion exchange reaction, and heteroepitaxy growth. It is discovered that this hierarchical oriented Cu(BDC‐OH) assemblies‐based generator containing long‐ranged ordered microporous channels exhibits a voltage of 0.6 V and electricity output of 1.56 nW cm–2 in the natural state of water evaporation. Finite element analysis and density functional calculation elucidate that hierarchical oriented structure of Cu(BDC‐OH) MOFs with certain surface charge density have an “aggregation effect,” dominating the final output voltages. This work not only offers valuable theoretical guidance for exploring self‐assembly of MOFs superstructures and water‐evaporation induced electricity generation, but also may open interesting perspectives for understanding some fundamental questions about structure‐activity relationship in MOFs materials science.

Beyond carbon nanotubes and graphene, we conduct a proof-of-principle study by using semiconducting graphdiyne (GDY) to fabricate high-performance n-type organic–inorganic flexible thermoelectric composites.