Deforestation affects freshwater assemblages since aquatic organisms are dependent on the structure of the riparian vegetation. To investigate the responses of riffle beetles (Elmidae) to ...deforestation, this study assessed the structure of riffle beetle assemblages found in streams running through a large and well-preserved semi-deciduous Atlantic Forest remnant in Southern Brazil and in nearby deforested areas. Additionally, the effects of different substrate types (litter and stone) on the assemblages were assessed. Riffle beetle assemblages showed a remarkably distinct structure between forested and deforested areas. Lower abundance occurred in deforested streams. Indicator genera of forested streams were detected (e.g.,Macrelmis and Microcylloepus), while a generalist genus (Heterelmis) predominated in deforested streams. Substrate type did not affect the composition of riffle beetle genera, although higher abundance was found in litter. Our results are likely associated with changes in the vegetation type and levels and quality of allochthonous material input between forested (native and higher levels) and deforested (exotic and lower levels) streams, which are directly linked to the feeding habits of riffle beetles. Thus, our study reveals an interesting potential of riffle beetles as indicators of stream ecological integrity in semi-deciduous areas of the Atlantic Forest biome.
The effects of forest conversion to agricultural land uses on assemblages of aquatic insects were analyzed in subtropical streams. Organisms and environmental variables were collected in six ...low-order streams: three streams located in a forested area, and three in areas converted to agricultural land uses. We expected that the aquatic insects’ assemblage attributes would be significantly affected by forest conversion, as well as by environmental variables. Streams in converted areas presented lower species richness, abundance and proportion of sensitive insect taxa. The ANOSIM test evidenced strong difference in EPT assemblage structure between streams of forested and converted areas. The ISA test evidenced several EPT genera with high specificity to streams in forested areas and only one genus related to streams in converted areas. Thus, the impacts of the conversion of forested area to agricultural land uses have significantly affected the EPT assemblages, while environmental variables were not affected. We suggest that the effects detected can be influenced by two processes related to vegetation cover: i) lower input of allochthonous material, andii) increased input of fine sediments in streams draining converted areas.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Children from mothers with HIV-related psychosis are frequently raised in challenging contexts, yet the extent to which these children grow up in insecure or disordered attachment relationships is ...unknown. Using the Strange Situation Procedure the distribution of attachment relationships of children from mothers with HIV and psychosis (n = 45) was compared with children from mothers with HIV without psychosis (n = 41). No significant differences in the distributions were found between the two groups and attachment was not associated with specific psychotic symptomatology. Security of attachment was associated with more people providing the mother with emotional support, but only in the psychosis group. Disordered attachment (24%) was more often found in the total sample than in studies with other normal and high risk populations. Recommendations were made for future research about factors facilitating resilience in the children and on interventions increasing emotional support for affected mothers.
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BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Parkinson's disease (PD) is characterized by difficulty with the timing of movements. Data collected using the synchronization-continuation paradigm, an established motor timing paradigm, have ...produced varying results but with most studies finding impairment. Some of this inconsistency comes from variation in the medication state tested, in the inter-stimulus intervals (ISI) selected, and in changeable focus on either the synchronization (tapping in time with a tone) or continuation (maintaining the rhythm in the absence of the tone) phase. We sought to re-visit the paradigm by testing across four groups of participants: healthy controls, medication naïve de novo PD patients, and treated PD patients both "on" and "off" dopaminergic medication. Four finger tapping intervals (ISI) were used: 250, 500, 1000, and 2000 ms. Categorical predictors (group, ISI, and phase) were used to predict accuracy and variability using a linear mixed model. Accuracy was defined as the relative error of a tap, and variability as the deviation of the participant's tap from group predicted relative error. Our primary finding is that the treated PD group (PD patients "on" and "off" dopaminergic therapy) showed a significantly different pattern of accuracy compared to the de novo group and the healthy controls at the 250-ms interval. At this interval, the treated PD patients performed "ahead" of the beat whilst the other groups performed "behind" the beat. We speculate that this "hastening" relates to the clinical phenomenon of motor festination. Across all groups, variability was smallest for both phases at the 500-ms interval, suggesting an innate preference for finger tapping within this range. Tapping variability for the two phases became increasingly divergent at the longer intervals, with worse performance in the continuation phase. The data suggest that patients with PD can be best discriminated from healthy controls on measures of motor timing accuracy, rather than variability.
Three closely related models for two-layered beams in which slip can occur at the interface are described. In the first, beam layers are modelled under the assumptions of Timoshenko beam theory. ...Along the interface, an adhesive layer of negligible thickness bonds the surfaces so that a small amount of slip is possible. Friction is assumed to be proportional to the rate of slip. The second is obtained from the first by letting the shear stiffness of each beam tend to infinity. The third is obtained from the second by assuming that the moment of inertia parameter is negligible. In the last case, an analog of the Euler–Bernoulli beam is obtained which exhibits frequency proportional damping characteristics. The three models are compared, both numerically and analytically, and found to be in close agreement for low frequency motions. Optimal damping rates are calculated for these low frequency motions.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The Born and Rytov approximations, widely used for solving scattering problems, are of limited utility for low‐frequency electromagnetic scattering in geophysical applications where conductivity can ...vary over many orders of magnitude. We present four new, relatively simple nonlinear estimators that can be used for rapid electromagnetic modeling. The first, termed the static localized nonlinear approximation, is designed specifically to correct the magnitude of the electric field internal to the scatterer. The second, termed the localized nonlinear approximation, improves the estimate of the phase of the scattered field and includes some of the cross‐polarization effects due to full wave scattering. Two further new estimators, based on the Rytov transformation (the localized nonlinear Rytov and the static localized nonlinear Rytov approximations) are designed to further improve the estimation of the phase of the scattered field, especially at high frequency and for larger size scatterers. Although these approximations are nonlinear functions in conductivity, they are generally much faster to compute than the full forward problem, and are almost as efficient as the Born or Rytov approximations. Moreover, the enhanced accuracy of the new estimators has made us optimistic about their application to low‐frequency three‐dimensional inverse problems in electromagnetics. The approximations developed in this paper will also be applicable to fields such as quantum mechanics, optics, ultrasonics, and seismology.
Inventories provide information on the state of biodiversity at a site or for a geographic region. Species inventories are the basis for systematic study and critical to ecology, biogeography and ...identification of biological indicators and key species. They also provide key information for assessments of environmental change, for natural resource conservation or recovery of degraded ecosystems. Thus, inventories play a key role in planning strategies for conservation and sustainable use. This study aimed to inventory the fauna of water beetles, larvae and adults, in two mountainous regions in the state of São Paulo, in Serra da Mantiqueira (Parque Estadual de Campos do Jordão and Pindamonhangaba region) and in Serra do Mar (Santa Virgínia and Picinguaba Divisions) as well as to generate information about the habitats used by the different genera recorded. Specimens were collected in lotic and lentic systems, between the years 2005 to 2010. In total 14,492 specimens were collected and 16 families and 50 genera of Coleoptera were identified. This study in mountainous regions showed a significant portion of the faunal composition of South America and the state of São Paulo. The composition of the fauna, in terms of richness and abundance by family, indicated the predominance of Elmidae, followed by Hydrophilidae and Dytiscidae. Despite the diversity found, the results of estimated richness indicated the need for additional sampling effort for both regions, since the curves of estimated richness did not reach an asymptote, suggesting that new species can be found in future surveys.
Massively open online courses (MOOCs) have received a great deal of attention, but little research exists on how they might fit into the existing system of higher education. We studied the impacts on ...learning outcomes of hybrid courses redesigned using online materials from MOOCs created on the Coursera platform and digital materials created by the Open Learning Initiative (OLI), relative to existing versions of the same courses. We found that student performance was about the same in both sections, as measured by pass rates and scores on common assessments. This finding held across a variety of disciplines and subgroups of students. We found no evidence supporting the worry that disadvantaged or academically underprepared students were harmed by taking hybrid courses with reduced class time. Despite the similar student outcomes produced by the two course formats, students in the hybrid sections reported considerably lower satisfaction with their experience.
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BFBNIB, DOBA, INZLJ, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, ZRSKP
Gilbert et al. conclude that evidence from the Open Science Collaboration's Reproducibility Project: Psychology indicates high reproducibility, given the study methodology. Their very optimistic ...assessment is limited by statistical misconceptions and by causal inferences from selectively interpreted, correlational data. Using the Reproducibility Project: Psychology data, both optimistic and pessimistic conclusions about reproducibility are possible, and neither are yet warranted.
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BFBNIB, NMLJ, NUK, ODKLJ, PNG, SAZU, UL, UM, UPUK
In 2010, 30% of South African women who were pregnant had HIV. In addition to possible loss of their mother in the future, children may also be affected by the secondary symptoms of AIDS. Psychotic ...symptoms are one such consequence that might disrupt the attachment relationship with children. This study was aimed to examine the published evidence on the linkages between HIV, psychosis and parenting. Databases were searched for studies on HIV/AIDS, psychosis and parenting; 51 relevant empirical studies were reliably identified and coded. No study simultaneously linked HIV/AIDS, psychosis and parenting. Twenty-three studies reported on the links between HIV infection and parenting, yielding various protective and risk factors, but not psychosis. Thirteen studies reported on the links between HIV and psychosis, with psychosis being a secondary outcome of later stages of AIDS, a side effect of medication or a comorbid disease because of common risk factors. Fourteen studies reported associations between psychosis and parenting. The impact of HIV infection of mothers on their parenting is beginning to be understood, but many underlying factors are still unknown. Psychosis appears to be a potent, but overlooked factor in supporting families affected by HIV/AIDS.
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