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Cells replicate and segregate their DNA with precision. Previous studies showed that these regulated cell-cycle processes were present in the last eukaryotic common ancestor and that their core molecular parts are conserved across eukaryotes. However, some metamonad parasites have secondarily lost components of the DNA processing and segregation apparatuses. To clarify the evolutionary history of these systems in these unusual eukaryotes, we generated a genome assembly for the free-living metamonad Carpediemonas membranifera and carried out a comparative genomics analysis. Here, we show that parasitic and free-living metamonads harbor an incomplete set of proteins for processing and segregating DNA. Unexpectedly, Carpediemonas species are further streamlined, lacking the origin recognition complex, Cdc6 and most structural kinetochore subunits. Carpediemonas species are thus the first known eukaryotes that appear to lack this suite of conserved complexes, suggesting that they likely rely on yet-to-be-discovered or alternative mechanisms to carry out these fundamental processes.

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© 2017 The International Society of Protistologists.Recent advances in molecular technology have revolutionized research on all aspects of the biology of organisms, including ciliates, and created unprecedented opportunities for pursuing a more integrative approach to investigations of biodiversity. However, this goal is complicated by large gaps and inconsistencies that still exist in the foundation of basic information about biodiversity of ciliates. The present paper reviews issues relating to the taxonomy of ciliates and presents specific recommendations for best practice in the observation and documentation of their biodiversity. This effort stems from a workshop that explored ways to implement six Grand Challenges proposed by the International Research Coordination Network for Biodiversity of Ciliates (IRCN-BC). As part of its commitment to strengthening the knowledge base that supports research on biodiversity of ciliates, the IRCN-BC proposes to populate The Ciliate Guide, an online database, with biodiversity-related data and metadata to create a resource that will facilitate accurate taxonomic identifications and promote sharing of data.

Morphology of Cothurnia salina n. sp. (Figs. 1, 2; Table 1) Diagnosis. Body elongated columnar, in vivo 80–98 × 12–19 µm; lorica barrel-shaped, with aboral part heavily thickened; stalk extremely short, with approximately ½ of its length within the lorica; macronucleus wormlike, longitudinally oriented; single contractile vacuole ventrally located; pellicle conspicuously striated, with 62–73 transverse and parallel striations between peristome and aboral trochal band, 32–38 between aboral trochal band and scopula; infundibular polykinety 3 (P3) consisting of two rows of kinetosomes, which are equal in length, parallel to each other and terminate adstomally between P1 and P2. Type location. Muping Salt Factory, Yantai, China (37°25'33.80"N, 121°45'14.20"E). Type material. A slide (registration number 11102201 –01) containing the holotype specimen (protargol preparation, marked by ink circle) and a paratype slide with protargol-stained specimens (registration number 11102201 –02) have been deposited in the Laboratory of Protozoology, Ocean University of China. Etymology. The specific epithet salina refers to the special hypersaline habitat of the new species. Description. Solitary, with slender, cylindroid cell body measuring 80–98 × 12–19 µm (Fig. 1 A, 2A, D, E); body widest at the peristomial lip and not constricted below it (Fig. 1 A, 2A, E). Peristomial lip lacks medial infolding and measures 21–27 µm in diameter. Pellicular striae visible above ×400 magnification (Fig. 2 E), with 62–73 striations from peristome to aboral trochal band and 32–38 from aboral trochal band to scopula (Table 1). Cytoplasm colorless or slightly grayish, usually containing several food vacuoles (diameter 5–10 µm) located in center of body. Single contractile vacuole located adorally, beneath peristomial lip and near ventral wall of infundibulum (Fig. 1 A, 2D). Macronucleus slender, cylindroid, longitudinally oriented (Fig. 1 A, 2F, G); micronucleus not observed. Lorica colorless, transparent, truncate pyriform, measuring 62–74 × 30–35 µm and aperture diameter of 21–30 µm. Aboral part of lorica thickened; wall 3 µm thick. Stalk 10 µm long, with approximately ½ of length exterior to lorica wall. Oral infraciliature as shown in Fig. 1 E, 2H. Haplokinety and polykinety make approximately one and one-half circuits together around peristome before entering infundibulum. Haplokinety and polykinety parallel to one another on peristome, diverging within infundibulum to lie on opposite walls (Fig. 1 E). Three infundibular polykineties (P1–3), with P1 and P2 consisting of three rows of kinetosomes and P3 of two rows. Adstomal ends of rows in P1 terminate at different levels, with inner row slightly shortened; P2 terminates adstomally above adstomal ends of P1 and P3, with row 3 not merging with P1 abstomally and significantly divergent from other two rows abstomally (Fig. 1 E). Rows of P3 parallel and equal in length, terminating adstomally at point approximately midway between adstomal ends of P2 and P1 (Fig. 1 E). Germinal kinety runs parallel to haplokinety in abstomal half of infundibulum (Fig. 1 E). Aboral trochal band consisting of series of dikinetids encircling cell at point 2/3 of distance from peristome to scopula (Fig. 2 E). Phylogenetic analysis based on SSU rRNA sequences (Fig. 3). The SSU rRNA gene sequence of Cothurnia salina (GenBank accession number KT956998) is 1,629 bp long and has a GC content of 43.09%. The sequence of C. salina differs from that of C. annulata (KU363275) by 38 nucleotides (sequence identity 97.4%); C. sp. 0 924 (KU363268) by 69 nucleotides (sequence identity 95.2%). Topologies of BI and ML trees were basically congruent, and thus, only the topology of the BI tree is presented in Fig. 3, with support values from both analyses indicated on branches. In both BI and ML trees, C. salina n. sp. clustered in the family Vaginicolidae as expected. C. salina n. sp. clustered with C. annulata with full support (1.00 BI, 100% ML) and these two species are sisters to the species C. sp. 0 924 with moderate support (0.80 BI, 57% ML). All data based on specimens in vivo. Abbreviations: Min, minimum; Max, maximum; Mean, arithmetic mean; SD, standard deviation; CV, coefficient of variation (%); n, number of individuals investigated.

Morphology of Cothurnia salina n. sp. (Figs. 1, 2; Table 1) Diagnosis. Body elongated columnar, in vivo 80���98 �� 12���19 ��m; lorica barrel-shaped, with aboral part heavily thickened; stalk extremely short, with approximately �� of its length within the lorica; macronucleus wormlike, longitudinally oriented; single contractile vacuole ventrally located; pellicle conspicuously striated, with 62���73 transverse and parallel striations between peristome and aboral trochal band, 32���38 between aboral trochal band and scopula; infundibular polykinety 3 (P3) consisting of two rows of kinetosomes, which are equal in length, parallel to each other and terminate adstomally between P1 and P2. Type location. Muping Salt Factory, Yantai, China (37��25'33.80"N, 121��45'14.20"E). Type material. A slide (registration number 11102201 ���01) containing the holotype specimen (protargol preparation, marked by ink circle) and a paratype slide with protargol-stained specimens (registration number 11102201 ���02) have been deposited in the Laboratory of Protozoology, Ocean University of China. Etymology. The specific epithet salina refers to the special hypersaline habitat of the new species. Description. Solitary, with slender, cylindroid cell body measuring 80���98 �� 12���19 ��m (Fig. 1 A, 2A, D, E); body widest at the peristomial lip and not constricted below it (Fig. 1 A, 2A, E). Peristomial lip lacks medial infolding and measures 21���27 ��m in diameter. Pellicular striae visible above ��400 magnification (Fig. 2 E), with 62���73 striations from peristome to aboral trochal band and 32���38 from aboral trochal band to scopula (Table 1). Cytoplasm colorless or slightly grayish, usually containing several food vacuoles (diameter 5���10 ��m) located in center of body. Single contractile vacuole located adorally, beneath peristomial lip and near ventral wall of infundibulum (Fig. 1 A, 2D). Macronucleus slender, cylindroid, longitudinally oriented (Fig. 1 A, 2F, G); micronucleus not observed. Lorica colorless, transparent, truncate pyriform, measuring 62���74 �� 30���35 ��m and aperture diameter of 21���30 ��m. Aboral part of lorica thickened; wall 3 ��m thick. Stalk 10 ��m long, with approximately �� of length exterior to lorica wall. Oral infraciliature as shown in Fig. 1 E, 2H. Haplokinety and polykinety make approximately one and one-half circuits together around peristome before entering infundibulum. Haplokinety and polykinety parallel to one another on peristome, diverging within infundibulum to lie on opposite walls (Fig. 1 E). Three infundibular polykineties (P1���3), with P1 and P2 consisting of three rows of kinetosomes and P3 of two rows. Adstomal ends of rows in P1 terminate at different levels, with inner row slightly shortened; P2 terminates adstomally above adstomal ends of P1 and P3, with row 3 not merging with P1 abstomally and significantly divergent from other two rows abstomally (Fig. 1 E). Rows of P3 parallel and equal in length, terminating adstomally at point approximately midway between adstomal ends of P2 and P1 (Fig. 1 E). Germinal kinety runs parallel to haplokinety in abstomal half of infundibulum (Fig. 1 E). Aboral trochal band consisting of series of dikinetids encircling cell at point 2/3 of distance from peristome to scopula (Fig. 2 E). Phylogenetic analysis based on SSU rRNA sequences (Fig. 3). The SSU rRNA gene sequence of Cothurnia salina (GenBank accession number KT956998) is 1,629 bp long and has a GC content of 43.09%. The sequence of C. salina differs from that of C. annulata (KU363275) by 38 nucleotides (sequence identity 97.4%); C. sp. 0 924 (KU363268) by 69 nucleotides (sequence identity 95.2%). Topologies of BI and ML trees were basically congruent, and thus, only the topology of the BI tree is presented in Fig. 3, with support values from both analyses indicated on branches. In both BI and ML trees, C. salina n. sp. clustered in the family Vaginicolidae as expected. C. salina n. sp. clustered with C. annulata with full support (1.00 BI, 100% ML) and these two species are sisters to the species C. sp. 0 924 with moderate support (0.80 BI, 57% ML). All data based on specimens in vivo. Abbreviations: Min, minimum; Max, maximum; Mean, arithmetic mean; SD, standard deviation; CV, coefficient of variation (%); n, number of individuals investigated., Published as part of Zhuang, Yuan, Clamp, John C., Yi, Zhenzhen & Ji, Daode, 2016, A new Peritrich Ciliate from a Hypersaline Habitat in Northern China, pp. 179-186 in Zootaxa 4169 (1) on pages 180-184, DOI: 10.11646/zootaxa.4169.1.10, http://zenodo.org/record/257123

The divisional process and systematic position of the marine scuticociliate Dexiotrichides pangi are studied. Based on both stomatogenetic data and 18S rDNA gene sequences, the phylogeny and morphogenetic characteristics of this taxon, and of other related genera, are analyzed and discussed. Both the divisionary events and the molecular biological data indicate that this species/genus, together with certain other genera in the Dexiotricha-complex, occupies an intermediate position between the tetrahymenids and the “typical” scuticociliate∼ which suggests that the Dexiotricha-like taxa should be excluded from the “true” scuticociliates. As a further contribution, the process of stomatogenesis in D. pangi can be summarized as follows: (1) The oral primordia in the opisthe are formed only by the proliferation of basal bodies in the scutica field, which subsequently develop into three membranelles, while the new paroral membrane seems to be generated by the sub-anterior portion of somatic kinety 1 (t...

This thesis examines the dynamics of employments relations in state-owned enterprises in China based on monographs produced in the Shanghai branches of two companies. In particular, it is intended to discuss the impact of transformations in the public sector from reforms in the 1980s. These reforms led to truly distinguish the interests of labor from those of management. In this sense, they paved the way for the emergence of a system of employments relations. This thesis focuses on the analysis of human resource policies in these companies, which were marked by increasing independence from the public authorities, the changing role of the union in this context, and the collective action of workers in the context of restructuring and uncertainty about the future of the company.; Cette thèse examine la dynamique des relations professionnelles dans les entreprises publiques en Chine, à partir de deux monographies réalisées dans des établissements situés à Shanghai. Elle s’interroge notamment aux conséquences des transformations du secteur public dans le prolongement des réformes engagées dans les années 1980. Ces réformes conduisent à distinguer véritablement les intérêts des salariés de ceux des directions d’entreprise. En ce sens, elles ouvrent la voie à l’émergence d’un système de relations professionnelles. Elle s’attache à l’analyse des politiques du personnel dans ces entreprises, marquées par une autonomisation croissante à l’égard des autorités publiques, à la transformation du rôle du syndicat dans ce contexte et à l’action collective des salariés notamment dans le contexte de restructurations et d’incertitude sur l’avenir de l’entreprise.

This article is a study of the specificity of labor conflicts in contemporary Chinese public enterprises. Its analysis is based on comparison of two cases : a purely public enterprise and a joint-venture with a multinational group. The employee mobilizations studied here reveal significant evolution since the major restructuring of the 1990s. Labor law is no longer simply a tool in the service of business policy ; it has become a resource used by employees to express their own interests. In open collective conflicts, it is seized upon in support of mobilization but it also allows for more individual strategies of mobility faced with what employees perceive as incoherent managerial policies. The discussion draws upon the classic exit/voice categories developed by Albert Hirschman to analyze the spectrum of mobilization, which ranges from open collective conflict to individual mobility.

Yi, Zhenzhen, Song, Weibo, Stoeck, Thorsten, Al-Rasheid, Khaled A. S., Al-Khedhairy, Abdulaziz A., Gong, Jun, Ma, Hongwei, Chen, Zigui (2009): Phylogenetic analyses suggest that Psammomitra (Ciliophora, Urostylida) should represent an urostylid family, based on small subunit rRNA and alpha-tubulin gene sequence information. Zoological Journal of the Linnean Society 157 (2): 227-236, DOI: 10.1111/j.1096-3642.2008.00524.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00524.x

Funder: Canadian Institutes of Health Research (Grant: FRN-142349) Natural Sciences and Engineering Research Council of Canada (Grant: RGPIN 05871-2014), Cells replicate and segregate their DNA with precision. Previous studies showed that these regulated cell-cycle processes were present in the last eukaryotic common ancestor and that their core molecular parts are conserved across eukaryotes. However, some metamonad parasites have secondarily lost components of the DNA processing and segregation apparatuses. To clarify the evolutionary history of these systems in these unusual eukaryotes, we generated a genome assembly for the free-living metamonad Carpediemonas membranifera and carried out a comparative genomics analysis. Here, we show that parasitic and free-living metamonads harbor an incomplete set of proteins for processing and segregating DNA. Unexpectedly, Carpediemonas species are further streamlined, lacking the origin recognition complex, Cdc6 and most structural kinetochore subunits. Carpediemonas species are thus the first known eukaryotes that appear to lack this suite of conserved complexes, suggesting that they likely rely on yet-to-be-discovered or alternative mechanisms to carry out these fundamental processes.