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Facial characteristics can serve as a cue for judgements of multiple human traits, from maternal tendencies, overall fertility to sexual openness. In this study, we tested previously found fluctuations in facial shape throughout the menstrual cycle. With methods more robust than those formerly used (larger sample size and detailed hormonal assessments determining the timing of the ovulation), we did not find significant changes in either of the three facial measurements conducted: symmetry, averageness and sexual dimorphism (all F ≤ 0.78, all partial η2 ≤ 0.01, all p ≥ 0.542). After narrowing the sample to cycles that had a higher probability of being ovulatory (based on daily measurements of luteinizing hormone and oestradiol), the results remained non-significant (all F ≤ 1.20, all partial η2 ≤ 0.03, all p ≥ 0.315). Our results (i) suggest that the previously found increased facial attractiveness of women in the most fertile phase of the menstrual cycle is not driven by changes in facial shape, but might instead stem from other changes in facial appearance, such as a more attractive skin tone; and (ii) underline the importance of replication of studies with new methods. [ABSTRACT FROM AUTHOR]

Although under investigation for more than two decades, a common agreement on the occurrence of cyclical shifts in women’s masculinity and symmetry preferences is still missing. Such shifts are considered to be an important feature of sexual selection as they supposedly direct women’s attention towards cues for “good genes” (e.g. masculinity and symmetry) during times when probability of conception is the highest. Multiple studies have, however, failed to find these shifts. We attempt to address this lack of agreement analysing a sample of 110 healthy women, using intra-participant design and repeated measurements of oestradiol and LH during the cycle. To ensure the reliable detection of increased conception probability, both LH- based ovulation tests and multiple oestradiol measurements were used. We found no significant differences between women’s preferences during different cycle phases for either body or facial masculinity, or for facial symmetry. Differences remained non-significant after controlling for participants’ sexual openness, relationship status, and self-judged attractiveness. We suggest that putative cyclical shifts in preferences for cues for good genes are either very small (impossible to be tracked even with a relatively large sample) or they are far more complex than previously assumed, and further studies accounting for more confounding variables should be undertaken. [ABSTRACT FROM AUTHOR]

The feather back, Notopterus notopterus is an important food fish. Its ovary is an extremely dynamic organ and the oocytes present an asynchronous development. Variations in ovary weight, GSI, diameter of oocytes were studied in different months of the year in this fish. Different developmental stages of female germ cells were identified on the basis of histological and ultrastructural characteristics in the ovary of N. notopterus (Pallas). In the present investigation the oocyte development of N. notopterus was divided into five stages (oogonia, perinucleolar oocyte, cortical alveolus, yolk granules stage and mature oocyte). The cytophysiological features like vitellogenesis, chorion formation and atresia of some follicles were also studied in the present investigation. The seasonal changes in the ovary have been described according to the variations in gonadosomatic index and the cytological changes of the female germ line cells. [ABSTRACT FROM AUTHOR]

The questions of ecology and taphonomy of radiolarians are reviewed and reexamined. In Recent oceans and seas, the major part of the “radiolarian rain” (dead individuals) comes from the layer of the water column which is not deeper than 500 m; therefore, the bottom radiolarian thanatocenoses and taphocenoses are formed in all oceanic zones, including the coastal and central oligotrophic regions of oceans. However, radiolarians should not be regarded as indicators of exclusively deepwater oceanic conditions. The crucial moments in the evolution of radiolarians at the major Phanerozoic boundaries are recognized. A dynamic model of cyclic development of radiolarians in the Phanerozoic is proposed and four phases and nine stages in their evolution are recognized. The absence of an outburst of radiolarian biodiversity in the Holocene is shown. Many great extinctions of radiolarians occurred at the boundaries between seasons of galactic years. [ABSTRACT FROM AUTHOR]

The Peel-Harvey Estuary in south-western Australia became so eutrophic in the 1970s and 1980s that a radical approach was adopted in order to increase tidal exchange between this estuary and the ocean and thereby flush greater volumes of nutrients out to sea. This involved constructing a deep artificial (Dawesville) channel between the estuary and the ocean, at a location ca. 15 km south of the shallower and natural (Mandurah) channel. Samples of fish larvae were collected monthly throughout 1997 to determine whether the characteristics of the ichthyoplankton on flood and ebb tides differed within and between channels and whether they underwent the same types of intra-annual changes in the two channels. In both channels, the number of species and concentration of larvae were both significantly greater on flood than ebb tides and the species composition differed significantly between tides. The concentrations of larvae were at their greatest, by far, between early spring and early autumn. Flood and ebb tides in both channels were dominated by the goby Favonigobius lateralis, which was transported out on ebb tides as preflexion larvae and subsequently brought back on flood tides as postflexion larvae. The larvae of Hyperlophus vittatus, Pseudorhombus jenynsii and Rhabdosargus sarba, which spawn outside the estuary, were far more abundant on flood than ebb tides, whereas the reverse pertained with Atherinosoma elongata, Apogon rueppellii and Pseudogobius olorum, which spawn within the estuary. In contrast to the situation with the diversity and concentration of larvae, the species composition on both flood and ebb tides differed significantly between channels. However, the latter differences were small and mainly due to relatively greater numbers of larval F. lateralis on ebb tides in the Mandurah Channel and the very occasional occurrence of reef species on flood tides in the Dawesville Channel. During the year, the species composition underwent cyclical changes on both tides and in both channels, due to out of phase sequential monthly changes in the concentrations of certain species. [Copyright &y& Elsevier]

Summary In mammals hair growth is cyclical; however, the factors that regulate the hair growth cycle are still poorly understood. The recent development of methods for culturing hair follicles in vitro has proved an important tool to investigate many aspects of the regulation of hair follicle growth. At present, however, these models are based on the culture of anagen hair follicles and have only partially been used to address the cyclical nature of hair growth. In this study we have made use of the fact that in rodents the hair growth cycle is synchronized, well characterized, and relatively short. We have isolated vibrissa follicles from 12 d old rats and confirmed by histology that these follicles are in the anagen stage of their first hair growth cycle. We have then maintained these follicles in vitro, on Gelfoam supports, for up to 23 d (35 d of age) and compared their histology with in vivo follicles from equivalent age littermates. We observed that 12 d old follicles maintained in vitro for up to 23 d show changes in morphology that suggest that cultured rat vibrissa follicles retain cyclical activity in vitro. Cyclical changes in hair follicle morphology were only seen in follicles maintained on gelfoam supports and moreover, hair follicle size appears to be a key feature in determining the ability of the follicle to cycle in vitro. All follicles that showed cyclical changes in vitro, however, appeared to remain blocked in pro-anagen. These data suggest that the vibrissa follicle is a in vitro good model system with which to investigate hair cycle control. J Invest Dermatol 115:1152–1155 2000. [ABSTRACT FROM AUTHOR]