The rational design of crystalline solids by self-organization of multiple molecular components is one of the interesting subjects in supramolecular chemistry, as it allows a defined spatial arrangement of the components and the formation of a diverse range of three-dimensional structures with unique functions.[1] In particular, the combination of organic compounds and inorganic metal clusters is interesting owing to their inherently different natures and possible synergetic effects in the crystal lattice. Polyoxometalates, anionic early transition metal oxide clusters, are attractive inorganic building blocks because of their discrete structures and notable acid/base, redox, and photochemical properties, which lead to a vast range of applications.[2, 3] Herein we report two porous hybrids assembled from a Keggin polyoxotungstate sodium salt (Na 3 PW 12 O 40 ) and calix[4]arene derivatives (1, 2) by host-guest interaction between the organic hosts and the sodium ion. [4] We also demonstrate the guest-sorption capabilities of these porous materials.Solutions of 1 in CHCl 3 and Na 3 PW 12 O 40 in MeOH were mixed and allowed to stand at room temperature to give single crystals of the 3:1 assembly [1-Na] 3 [PW 12 O 40 ] (3). X-ray crystallographic studies revealed the formation of an infinite ionic crystal with a cubic crystal system, which contained a head-to-tail columnar array of the 1-Na + complexes as a fundamental component. As shown in Figure 1 a, the columns propagate in three directions along the a, b, and c axes and are stacked alternately in orthogonal configurations to generate a three-dimensional gridlike framework, which serves as a scaffold for the a- [PW 12 O 40 ] 3À anions. One anion is surrounded by six 1-Na + units, whereby no bonding interactions between sodium and cluster oxygen atoms are observed (Figure 1 b).[5] The side faces of each calix[4]arene unit are involved in weak intermolecular interactions with the anions (e.g., van der Waals forces).[6] Packing of the cationic and anionic components in this manner leaves micropores as the residual space. As shown in Figure 1 a and c, cavities with sizes of about 6 9 are created between four calix[4]arene units, which extend along the a axis to form channels. Channels are Figure 1. Crystal structure of 3 with solvent molecules omitted. a) A view of the packing structure along the a axis illustrating orthogonal stacking of the 1-Na + columns running along the a, b, and c axes. b) Octahedral orientation of 1-Na + units around a cluster anion. c) A cross section of the microchannel viewed along the a axis. The black lines in (a) indicate the unit cell, and the dotted lines the microchannels.

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Spermatogenesis in a parthenogenetic type of P. westermani (Kerbert 1878) called P. pulmonalis (Baelz 1880) throughout this study, was observed by light microscopy (LM), scanning (SEM), and transmission (TEM) electron microscopy. During spermatogenesis, most of the cells became degenerated or malformed as a result of aberrations during spermatogenesis. Vacuolated cells were often found in the testicular lumen. In some nuclei of spermatocytes, synaptonemal complexes were formed and this indicated that some pairing of homologous chromosomes did occur, but only rarely. Cytophores in some rosettes were broken down into small fragments and the cells separated from each other. Norman spermatozoa were very rarely found in the testis and never in the seminal receptacle, where egg and vitelline cells were present instead. Throughout spermatogenesis, Golgi complexes, mitochondria, ribosomes, and endoplasmic reticulum were not abundant, and this suggested that cell activities and protein synthesis were greatly reduced.