The aim of this study was to investigate whether there is an association between antenatal mood state (depression and anxiety) and psychological adjustment to pregnancy. Participants were first-time, low obstetric risk mothers at a Sydney teaching hospital who completed self-report questionnaires measuring depression, anxiety, thoughts about motherhood and self as mother and relationship with the fetus. Higher symptom levels of antenatal anxiety were related to less optimal maternal-fetal quality of attachment, more negative attitudes towards motherhood and the self as mother. Similar trends were found for symptoms of depression, however depression was not significantly related to psychological adjustment to pregnancy variables. The significance of anxiety in the current study highlights the importance of considering anxiety in the psychological adjustment to pregnancy, as well as the in the context of perinatal mental health more generally. Implications of these findings for intervention are also briefly discussed.

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A collation of post-embryonic durations for freshwater and marine calanoid, cyclopoid and harpacticoid copepods is provided, and examined for patterns and conformities which may be of predictive value. Most of the analysis concerns calanoids. Only the genus Acartia exhibits evidence of equal stage duration (isochronality). Accordingly, isochronal development must be rejected as a general pattern in copepods -with various implications to the study of their production. Conversely, relative stage durations are surprisingly comparable in a wide range of copepods across a broad range of temperatures and food levels. A loose consistency is evident among copepod species generally, (interspec@ equiproportionality), but within given genera, a striking regularity, here termed intergeneric equiproportionality (IGE) is evident.Patterns of IGE are consistent with selectively adaptive life-history traits, and IGE thus offers predictive prospects which are of both quantitative and qualitative (heuristic) value. Empirical support which exists for IGE among marine calanoids suggests that in contrast to isochronality and interspecific equiproportionality, IGE is indeed a real, and ultimately quantifiable feature of copepod development.Within calanoids, the ratio of total copepodid to total naupliar duration (DclDn) appears independent of temperature, shows little relationship to adult body mass, but is inversely related to food supply, markedly so in freshwater forms. In this context, changes in the ratio are attributable largely to influences of food supply upon copepodid development times : naupliar durations appear relatively independent of food concentrations during development. Considerably higher DclDn ratios in freshwater than in marine calanoids conceivably arise from selective influences of different nutritional conditions and size-selective predation pressures in freshwater and marine environments. In the generally high predation environment of freshwaters, acceleration of naupliar development potentially reduces the vulnerability of these smaller stages to size-selective tactile predation, while larger copepodid instars are able to reduce the opposing size-selective influences of visual planktivores by virtue of their escape responses to suction attack. Within the spectrum of copepod life histories and development schedules, ecologically consistent trends of this nature await formal recognition. The present recognition of IGE is a modest initiative in this quest.Both naupliar and copepodid durations are inverse monotonic functions of temperature. Several mathematical expressions which account for this temperature-duration response are provided. The response envelope is much tighter for naupliar than copepodid durations. Predictability of temperatureduration responses accordingly declines ontogenetically from egg to naupliar to copepodid stages.

In view of its fundamental and pervasive influences and impacts on organism physiology and ecology, body size is recognized as a key component of evolutionary fitness and serves as the cornerstone of a seminal contribution in freshwater zooplankton ecology-the Size Efficiency Hypothesis (SEH) of Brooks & Dodson (Science 150:28-35, 1965). While the roles and implications of body size in predation and competition-central tenets of the SEH-have been widely considered and reviewed, no broader integrated synthesis exists of the collective array of body size determinants and their implications in the ecology in crustacean zooplankton-a numerically and functionally dominant group of aquatic organisms. Focusing on planktonic Cladocera and Copepoda in inland waters, in particular, we provide a wide-ranging overview of the direct and/or indirect effects of environmental conditions, consumable resources and biotic interactions that independently and/or collectively influence the phenotypic expression of body size (particularly as length), both within and between species. Some indirect ultimate evolutionary consequences of body size are considered, and we identify some controversies and unresolved issues related to this biologically crucial trait. While by no means exhaustive, our overview reveals a complex nexus of extrinsic proximate abiotic and biotic factors and interactions that influence body size, the phenotypic expression of which in natural systems commonly reflects contrasting outcomes related to conflicting direct and/or indirect selective pressures. In general, however, body size (both interand intra specifically) declines with rising temperature and increases with rising food supply (depending on its quality), although both temperature and food supply exert contrary influences on particular taxa (or life history stages) under certain environmental circumstances. Predation undoubtedly has an overriding influence on body size selection. Depending on its mechanistic basis (visual, tactile or both in tandem), it selectively favours either small or large body size, both within (adults vs. juveniles) and between prey species, which are accordingly often 'size-trapped' between contrasting selective pressures, with consequent indirect effects. The bioenergetics of fundamental physiological processes undoubtedly set constraints on body size and serve as the primary determinant. However, within such

A mechanistic understanding of the pathology of psychiatric disorders has been hampered by extensive heterogeneity in biology, symptoms, and behavior within diagnostic categories that are defined subjectively. We investigated whether leveraging individual differences in information-processing impairments in patients with post-traumatic stress disorder (PTSD) could reveal phenotypes within the disorder. We found that a subgroup of patients with PTSD from two independent cohorts displayed both aberrant functional connectivity within the ventral attention network (VAN) as revealed by functional magnetic resonance imaging (fMRI) neuroimaging and impaired verbal memory on a word list learning task. This combined phenotype was not associated with differences in symptoms or comorbidities, but nonetheless could be used to predict a poor response to psychotherapy, the best-validated treatment for PTSD. Using concurrent focal noninvasive transcranial magnetic stimulation and electroencephalography, we then identified alterations in neural signal flow in the VAN that were evoked by direct stimulation of that network. These alterations were associated with individual differences in functional fMRI connectivity within the VAN. Our findings define specific neurobiological mechanisms in a subgroup of patients with PTSD that could contribute to the poor response to psychotherapy.

1. Changes in zoopiankton composition and abundance in Lake le Roux, a turbid subtropical reservoir on the Orange River in South Africa, were correlated with changes in water transparency (related to suspended sediment levels) during a 7 year field study. Results of radiotracer studies of the effect of mineral turbidity on zooplankton feeding rates whieh potentially influence competitive ability, and thus community structure, are reported here.2. Feeding rates of five zooplankters were very variable, but consistently declined with rising turbidity: rates of decline differed between species. A regression estimate of the critical turbidity threshold at which food intake matched the estimated respiratory need was derived for each species. This yielded the following 'turbidity-tolerance" ranking: Moina hrachiata Jurine > Metadiaptomus meridiantis (van Douwe) > Dapluua gihba Methuen > D. barbata Weltner > D. longispina O. F. Muller. The consistency between this ranking and one based upon abundance-transparency relationships in the field study suggests that community structure is related to differential feeding capabilities, although other influences are not exeluded.3. Tests on D. gibba and M. meridianus failed to reveal any detectable feeding rate saturation (incipient limiting food level) below I.2mg r'C. The relative reduction in feeding rates at elevated turbidity was nearly 3 times greater for the daphnid than the copepod over a range of food concentrations, and considerably reduces the competitive ability of this (and other) daphnids. The turbidity tolerance disparity between Moina and the daphnids demonstrates a more complex situation than a simple copepod/cladoceran dichotomy. These findings and their implieations are discussed in relation to wider features of zooplankton ecology.

1. The abundance and composition of entomostracan zooplankton were studied between 1977 and 1984 in relation to abiotic and biotic conditions in Lake le Roux (LLR), a large silt-laden reservoir on the Orange River formed in 1976. The community consisted of Meladiaptomus meridianus, Lovenuta excellens (Calanoida), Daphnia gibha, D. burbata, D. longispina and Moina brachiata (Cladocera), and various Cyclopoida.2. Zooplankton biomass varied seasonally from winter lows below 50mgm~^ dry wt at temperatures of 9-10°C to summer peaks generally above 1000mgm"" at 21-23°C. It correlated strongly and positively with prevailing water temperature and transparency but only weakly with chlorophyll concentration.3. Mean annual zooplankton biomass, which varied four-fold (97-408 mgm"*^) in 7 years, increased with annual mean transparency (23-75 cm Secchi depth) and especially with summer heat content (33-230 degree-days above 20°C) which was itself positively correlated with transparency.4. Daphnid species showed most annual variation in abundance. Large forms (D. gibbu and D. bcirtmta) were scarce or absent in two years of very low transparency and low planktivore abundance. The smaller D. longispina developed once during clearer conditions when more fish were present. Copepod biomass also varied inversely with turbidity, but was not as severely reduced at high turbidities. 5. Smallmouth yellowfish {Barbus aeneus: Cyprinidae) is the principal planktivore and candidate fishery species in LLR. It feeds selectively on Lovenuta and large daphnids. Catches and growth rates of yellowfish varied directly with the abundance of zooplankton, particularly large food forms, and with water transparency. High turbidity and associated food limitation seems to reduce standing stocks especially of the daphnid zooplankton more than the effects of fish predation.

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