"O rg a n ic Superconductors" by T ishiguro and K Y am aji is a recent publication in the w e ll-k n o w n "S pringer Series in S o lid State S cien ces". Chapter 6 is on DMET and MDT-TTF superconductors. DMET is a hybrid between TMTSF and ET molecular groups and hence interesting. Superconduc tivity in MDT-TTF is more interesting as it is a cross between tw o apparently non-superconducting groups TTF and BMDT-TTF. Chapter 1 is on DHIT salts. These superconductors are ir-anion molecules white the earlier ones have been rr-cation molecules. The authors are involved, along w ith th e ir colleagues a t th e KyotoThe mechanism of superconductivity in organic materials, which is yet to be decided from among a few possible mechanisms, is expertly documented in Chapters. Outline of BCS theory, s-, p-, d-pairings and singlet and triplet superconductivity are given w ith notes on Little's models of 1964 and 1983. Next the possibility of superconductivity from spin fluctuations in (TMTSF)*X, for example, is reviewed. That this mechanism is hotly debated for explaining high T, superconductivity has also been noted by the authors. They next explain 9

Endometriosis is characterized by ectopic endometrial-like epithelium and stroma, of which molecular characteristics remain to be fully elucidated. We sequenced 107 ovarian endometriotic and 82 normal uterine endometrial epithelium samples isolated by laser microdissection. In both endometriotic and normal epithelium samples, numerous somatic mutations were identified within genes frequently mutated in endometriosis-associated ovarian cancers. KRAS is frequently mutated in endometriotic epithelium, with a higher mutant allele frequency (MAF) accompanied by arm-level allelic imbalances. Analyses of MAF, combined with multiregional sequencing, illuminated spatiotemporal evolution of the endometriosis and uterine endometrium genomes. We sequenced 109 single endometrial glands and found that each gland carried distinct cancer-associated mutations, demonstrating the heterogeneity of the genomic architecture of endometrial epithelium. Remarkable increases in MAF of mutations in cancer-associated genes in endometriotic epithelium suggest retrograde flow of endometrial cells already harboring cancer-associated mutations, with selective advantages at ectopic sites, leading to the development of endometriosis.

Recently, many types of in vitro 3‐D culture systems have been developed to recapitulate the in vivo growth conditions of cancer. The cancer 3‐D culture methods aim to preserve the biological characteristics of original tumors better than conventional 2‐D monolayer cultures, and include tumor‐derived organoids, tumor‐derived spheroids, organotypic multicellular spheroids, and multicellular tumor spheroids. The 3‐D culture methods differ in terms of cancer cell sources, protocols for cell handling, and the required time intervals. Tumor‐derived spheroids are unique because they are purposed for the enrichment of cancer stem cells (CSCs) or cells with stem cell‐related characteristics. These spheroids are grown as floating spheres and have been used as surrogate systems to evaluate the CSC‐related characteristics of solid tumors in vitro. Because eradication of CSCs is likely to be of clinical importance due to their association with the malignant nature of cancer cells, such as tumorigenicity or chemoresistance, the investigation of tumor‐derived spheroids may provide invaluable clues to fight against cancer. Spheroid cultures have been established from cancers including glioma, breast, colon, ovary, and prostate cancers, and their biological and biochemical characteristics have been investigated by many research groups. In addition to the investigation of CSCs, tumor‐derived spheroids may prove to be instrumental for a high‐throughput screening platform or for the cultivation of CSC‐related tumor cells found in the circulation or body fluids.

The temperature (T) dependent dc conductivity (s DC) (down to 20 mK) and dielectric function at optical frequencies (0.002-6 eV) and 6.5 GHz are used to probe the inhomogeneous disorder-driven insulator-metal transition in conducting polymers. A correlation between large low T s DC and the presence to low T of a small fraction of the carrier density delocalized with long transport times (.10 213 s) indicates that metallic s DC is due to only a small fraction of the charge carriers. The achievable s DC for these systems when the entire charge carrier density participates is estimated to surpass that of copper. [S0031-9007(97)03024-X]

We investigated the behavior of the spin-triplet superconductor Sr2RuO4 ( T(c) approximately 1.5 K) under the magnetic fields parallel to the quasi-two-dimensional plane. The upper critical field H(c2) exhibits a clear fourfold anisotropy of about 3% at 0.35 K. Furthermore, we detected an additional transition feature below H(c2) in both the ac susceptibility and the specific heat. These second-transition features as well as the pronounced in-plane H(c2) anisotropy disappear above 0.8 K or under intentional field misalignment of less than 1 degrees. Most of these characteristics are consistent with the predicted emergence of the second superconducting phase with a line-node gap.

We studied the specific heat and thermal conductivity of the spin-triplet superconductor Sr2RuO4 at low temperatures and under oriented magnetic fields H. We have resolved a double peak structure of the superconducting transition under magnetic field for the first time, which provides thermodynamic evidence for the existence of multiple superconducting phases. We also found a clear limiting of the upper critical field Hc2 for the field direction parallel to the RuO2 plane only within ±2 • . The limiting of Hc2 occurs in the same H − T domain of the second superconducting phase; we suggest that the two phenomena are of the same physical origin.

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The thermal conductivity κ of the quasi-two-dimensional (Q2D) organic superconductor λ-(BETS)2GaCl4 was studied in the magnetic field H applied parallel to the Q2D plane. The phase diagram determined from this bulk measurement shows notable dependence on the sample quality. In dirty samples the upper critical field Hc2 is consistent with the Pauli paramagnetic limiting, and a sharp change is observed in κ(H) at H c2 . In contrast in clean samples Hc2(T ) shows no saturation towards low temperatures and the feature in κ(H) is replaced by two slope changes reminiscent of second-order transitions. The peculiarity was observed below ∼0.33Tc and disappeared on field inclination to the plane when the orbital suppression of superconductivity became dominant. This behavior is consistent with the formation of a superconducting state with spatially modulated order parameter in clean samples.