Descriptions of two Copidognathus halacarid mites (Acari, Halacaridae) from Zanzibar, Tanzania

Two halacarid species of the genus Copidognathus (Acari, Halacaridae) collected from the east coast of Unguja, Zanzibar, Tanzania, are described. Copidognathus matemwensis sp. nov. is characterized by an anterodorsal plate with 3 areolae, posterior dorsal plate with 2 costae, pair of ventromedial areolae between lateral and posterior setae on anterior epimeral plate, areolae present on lateral side of anterior half of genitoanal plate tending to join the areolae laterally to the genital opening area, rostrum elongate, tibiae I and II each with 1 denticulate process proximoventrally. The male of Copidognathus corallorum (Trouessart, 1899) is reported for the first time and described; leg morphology for C. corallorum is provided

Impacts of residential relocation on stress, coping and quality of life among older persons in Hong Kong

Residential relocation could potentially be injurious to older persons. Indeed, much of the research literature in Western societies points out that involuntary residential relocation may exert undesirable impacts on older persons’ lives. Those impacts could be even greater if the relocation was forced upon the individual one person. Therefore, the purpose of this research is to investigate the impacts of involuntary residential relocation on older persons’ quality of life, stress and coping in Hong Kong. From a review of the literature, it was hypothesized that there will be perceived stress during and after the process of residential relocation, and satisfaction with relocation arrangement and quality of elderly life are related. This research method adopted was a one-shot group pretest-posttest experimental design with a panel study, having the dual purposes of explanation and description. Structured and semi-structured questionnaires were used to collect quantitative data and qualitative data in order to test the hypotheses, and provide subsequent policy information for the service and care providers. A total of 85 and 74 older persons were interviewed in the pretest (male=19 and female=66) and the posttest (male=15 and female=59) respectively. They were recruited from two public housing estates: Valley Road Estate and Ho Man Tin Estate, and almost all of them were finally relocated to Ho Man Tin South, effectively a relatively short-distance intra-urban relocation. Most of the hypotheses of the study could be supported. The findings indicate that the respondents perceived stress from the relocation and associated financial strains from the costs. The greatest stress they faced was the processes before the actual move. Moreover, the results also revealed that their quality of life, both in the pretest and posttest studies, was statistically and significantly correlated to their stress, coping strategies and satisfaction with the existing housing. In addition, more than half of the respondents expressed the view that the non-government organizations gave them the greatest help or assistance in this stressful life event. Nonetheless, the respondents showed that they experienced higher levels of stress and lower satisfaction with new estate after the move in spite of the objectivity better living conditions. They also indicated that they had a lower quality of life and poorer coping strategies after the move. Thus, it appears that residential relocation is not generally favorable for successful ageing. Furthermore, the female respondents and older persons who lived alone reported that they experienced more problems in the move than other respondents. The older residents from Valley Road Estate had greater satisfaction with the new housing than those from Ho Man Tin Estate perhaps because their residential environmental improvement were greater, offsetting some stresses of the move. Last but not least, some constructive suggestions were offered to all players, including the Housing Authority, the NGOs, the older persons and their families

Turn-by-Turn Imaging of the Transverse Beam Profile in PEP-II

During injection or instability, the transverse profile of an individual bunch in a storage ring can change significantly in a few turns. However, most synchrotron-light imaging techniques are not designed for this time scale. We have developed a novel diagnostic that enhances the utility of a fast gated camera by adding, inexpensively, some features of a dual-axis streak camera, in order to watch the turn-by-turn evolution of the transverse profile, in both x and y. The beam's elliptical profile is reshaped using cylindrical lenses to form a tall and narrow ellipse—essentially the projection of the full ellipse onto one transverse axis. We do this projection twice, by splitting the beam into two paths at different heights, and rotating the ellipse by 90° on one path. A rapidly rotating mirror scans these vertical “pencils” of light horizontally across the photocathode of the camera, which is gated for 3 ns on every Nth ring turn. A single readout of the camera captures 100 images, looking like a stroboscopic photograph of a moving object. We have observed the capture of injected charge into a bunch and the rapid change of beam size at the onset of a fast instability

Autochthony and isotopic niches of benthic fauna at shallow-water hydrothermal vents

The food webs of shallow-water hydrothermal vents are supported by chemosynthetic and photosynthetic autotrophs. However, the relative importance of these two basal resources for benthic consumers and its changes along the physicochemical gradient caused by vent plumes are unknown. We used stable carbon and nitrogen isotopes (i.e., delta C-13 and delta N-15) and Bayesian mixing models to quantify the dietary contribution of basal resources to the benthic fauna at the shallow-water vents around Kueishan Island, Taiwan. Our results indicated that the food chains and consumer production at the shallow-water vents were mainly driven by photoautotrophs (total algal contribution: 26-54%) and zooplankton (19-34%) rather than by chemosynthetic production (total contribution: 14-26%). Intraspecific differences in the trophic support and isotopic niche of the benthic consumers along the physicochemical gradient were also evident. For instance, sea anemone Anthopleura sp. exhibited the greatest reliance on chemosynthetic bacteria (26%) and photoautotrophs (66%) near the vent openings, but zooplankton was its main diet in regions 150-300 m (32-49%) and 300-700 m (32-78%) away from the vent mouths. The vent-induced physicochemical gradient structures not only the community but also the trophic support and isotopic niche of vent consumers

Metamorphosis in balanomorphan, pedunculated, and parasitic barnacles:a video-based analysis

Cypris metamorphosis was followed using video microscopy in four species of cirripeds representing the suspension-feeding pedunculated and sessile Thoracica and the parasitic Rhizocephala. Cirripede metamorphosis involves one or more highly complex molts that mark the change from a free cypris larva to an attached suspension feeder (Thoracica) or an endoparasite (Rhizocephala). The cyprids and juveniles are so different in morphology that they are functionally incompatible. The drastic reorganization of the body implicated in the process can therefore only commence after the cyprid has irreversibly cemented itself to a substratum. In both Megabalanus rosa and Lepas, the settled cyprid first passes through a quiescent period of tissue reorganization, in which the body is raised into a position vertical to the substratum. In Lepas, this is followed by extension of the peduncle. In both Lepas and M. rosa, the juvenile must free itself from the cypris cuticle by an active process before it can extend the cirri for suspension feeding. In M. rosa, the juvenile performs intensely pulsating movements that result in shedding of the cypris carapace ∼8 h after settlement. Lepas sp. sheds the cypris cuticle ∼2 days after settlement due to contractile movements of the peduncle. In Lepas anserifera, the juvenile actively breaks through the cypris carapace, which can thereafter remain for several days without impeding cirral feeding. Formation of the shell plates begins after 1-2 days under the cyprid carapace in Lepas. In M. rosa, the free juvenile retains its very thin cuticle and flexible shape for some time, and shell plates do not appear until sometime after shedding of the cypris cuticles. In Sacculina carcini, the cypris settles at the base of a seta on the host crab and remains quiescent and aligned at an angle of ∼60° to the crab’s cuticle. The metamorphosis involves two molts, resulting in the formation of an elongated kentrogon stage with a hollow injection stylet. Due to the orientation of the cyprid, the stylet points directly towards the base of the crab’s seta. Approximately 60 h after settlement the stylet penetrates down one of the cyprid antennules and into the crab. Almost immediately afterwards the unsegmented vermigon stage, preformed in the kentrogon, passes down through the hollow stylet and into the crab’s hemocoel in a process lasting only 30 s. In S. carcini, the carapace can remain around the metamorphosing individual without impeding the process

Chapter 7 Review: Effects of Microplastic on Zooplankton Survival and Sublethal Responses

Microplastics (MPs) are a prolific contaminant in aquatic ecosystems across the globe. Zooplankton (including holoplankton and meroplankton) play vital ecological roles in marine and freshwater ecosystems and have been shown to readily consume MPs. The present review uses 88 pieces of published literature to examine and compare the effects of MPs on survival, growth, development, feeding rate, swimming speed, reproduction, organ damage and gene expression of different groups of zooplankton including copepods, daphnids, brine shrimp, euphausids, rotifers and the larvae of fishes, sea urchins, molluscs, barnacles, decapods and ascidians. Among the groups studied, daphnids and copepods are the most sensitive to MPs, with their feeding rate and fecundity significantly decreased at environmentally relevant MP concentrations. This might adversely affect daphnids and copepods populations in the long term. In contrast, molluscs, barnacles, brine shrimp and euphausids appear to be more tolerant to MPs. No clear impacts on survival, development time, growth or feeding rate can be observed in these zooplankton groups at any of the MP concentrations tested, suggesting that these groups might become more dominant with prolonged exposure to MP pollution. Leachates derived from MPs can induce severe abnormality in bivalve and sea urchin embryos. MPs have prominent effects on survival and fecundity of F1 offspring in bivalves, copepods and daphnids, indicating that MPs could incite transgenerational effects and drastically affect sustainability in zooplankton populations

A Terbium Chlorobismuthate(III) Double Salt: Synthesis, Structure, and Photophysical Properties

We report on the structure and luminescence of a double salt trivalent rare earth ion acceptor, Tb3+, with octahedral [BiCl6]3– donor clusters. The novel TbBiCl6·14H2O (1) was prepared from aqueous BiOCl and TbCl3·6H2O. The crystal structure of compound 1 exhibits isolated [BiCl6]3– and [Tb(OH2)8]3+ clusters. Luminescence data show energy transfer from octahedral chlorobismuthate(III) clusters to rare earth metal ions. Density Functional Theory (DFT) calculations show distinctly different emission pathways at high and low excitation energies