Predaceous water beetles (Coleoptera, Hydradephaga) of the Lake St Lucia system, South Africa: biodiversity, community ecology and conservation implications

Water beetles are one of the dominant macroinvertebrate groups in inland waters and are excellent ecological indicators, reflecting both the diversity and composition of the wider aquatic community. The predaceous water beetles (Hydradephaga) make up around one-third of known aquatic Coleoptera and, as predators, are a key group in the functioning of many aquatic habitats. Despite being relatively well-known taxonomically, ecological studies of these insects in tropical and subtropical systems remain rare. A dedicated survey of the hydradephagan beetles of the Lake St Lucia wetlands (South Africa) was undertaken between 2013 and 2015, providing the first biodiversity census for this important aquatic group in the iSimangaliso Wetland Park, a UNESCO World Heritage Site within the Maputaland biodiversity hotspot. A total of 32 sites covering the entire spectrum of waterbody types were sampled over the course of three collecting trips. The Lake St Lucia wetlands support at least 68 species of Hydradephaga, a very high level of diversity comparing favourably with other hotspots on the African continent and elsewhere in the world and a number of taxa are reported for South Africa for the first time. This beetle assemblage is dominated by relatively widespread Afrotropical taxa, with few locally endemic species, supporting earlier observations that hotspots of species richness and centres of endemism are not always coincident. Although there was no significant difference in the number of species supported by the various waterbody types sampled, sites with the highest species richness were mostly temporary depression wetlands. This contrasts markedly with the distribution of other taxa in the same system, such as molluscs and dragonflies, which are most diverse in permanent waters. Our study is the first to highlight the importance of temporary depression wetlands and emphasises the need to maintain a variety of wetland habitats for aquatic conservation in this biodiverse region

História, sociologia e análise do poder

This text discusses the relationship between History and Sociology in contemporary sociological literature, especially in Michel Foucault and Pierre Bourdieu. It argues that the concept of power as understood by both French authors demands, methodologically speaking, the collaboration between the sociological approach and historical analysis. Key words: History, Sociology, Power.Este texto discute a relação entre história e sociologia na produção sociológica contemporânea, notadamente em autores como Michel Foucault e Pierre Bourdieu. O artigo defende que o conceito de poder tal como elaborado por esses dois autores exige, metodologicamente falando, a colaboração entre a abordagem sociológica e a análise histórica. Palavras-chave: História, Sociologia, poder

Laser cleaning of diagnostic mirrors from tokamak-like carbon contaminants

This paper presents a laboratory-scale experimental investigation of laser cleaning of diagnostic First Mirrors (FMs). Redeposition of contaminants sputtered from tokamak first wall onto FMs surface could dramatically decrease their reflectivity in an unacceptable way for the functioning of the plasma diagnostic systems. Laser cleaning is a promising solution to tackle this issue. In this work, pulsed laser deposition was exploited to produce rhodium films functional as FMs and to deposit onto them carbon contaminants with tailored features, resembling those found in tokamaks. The same laser system was also used to perform laser cleaning experiments by means of a sample handling procedure that allows to clean some cm(2) in few minutes. The cleaning effectiveness was evaluated in terms of specular reflectivity recovery and mirror surface integrity. The effect of different laser wavelengths (lambda = 1064, 266 nm) on the cleaning process is also addressed

Sculpting neurotransmission during synaptic development by 2D nanostructured interfaces

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First records of Gastrotricha from South Africa, with description of a new species of Halichaetonotus (Chaetonotida, Chaetonotidae)

During a survey of the biota of the St. Lucia Estuary in the iSimangaliso Wetland Park, South Africa, a number of Gastrotricha were found among samples of meiofauna. Fresh, marine sediment yielded several specimens belonging to a total of seven species. Of these, two are already known from other regions (i.e., Dactylopodola australiensis and Heteroxenotrichula squamosa), one is described as new to science (Halichaetonotussanctaeluciae sp. n.), while the remaining four (Pseudostomella sp., Halichaetonotus sp.1, Halichaetonotus sp. 2, Xenotrichula sp.) require further collections and analysis, in order to establish the extent of their affiliation to species already described. General appearance, shape of hydrofoil scale and the occurrenceof three long spines on the dorsal side make the new species most closely related to H. australis and H. marivagus. The key differences from these taxa and between Halichaetonotus sanctaeluciae sp. n. and H. aculifer are discussed

Magnetic resonance imaging assessment of lipomatous soft-tissue tumors

Aim: To establish the accuracy of magnetic resonance imaging (MRI) in distinguishing between benign and malignant lipomatous tumors; to evaluate the reproducibility of the MRI interpretation assessing the agreement between judgments of two radiologists with the same experience in soft-tissue sarcomas; to identify an association among MRI findings (size, depth, septa, nodules, signal homogeneity) and nature of the lesion. Materials and Methods: A total of 54 patients (28 men and 26 women), with a mean age of 56 (range=27-84) were included years. All subjects followed-up by the Multidisciplinary Sarcoma Group. The following MRI findings were judged in a blind study by two radiologists: Size, localization, septa, nodules and signal homogeneity. A diagnostic indication was then given from among lipoma, atypical lipomatous tumour (ALT) and liposarcoma. Accuracy in distinguishing between benign and malignant lesions, and between lipoma and ALT (Fisher's exact test), inter-operator agreement (Cohen's kappa), association of MRI findings and malignancy of the lesion (Fisher's exact test and odds ratio) were evaluated. Results: The inter-operator agreement was complete (100%). The agreement between diagnostic hypothesis and histological diagnosis was statistically significant (p<0.05). Among the radiological findings taken into account, only septa and signal homogeneity were significantly associated with the malignancy of the lesion (p<0.05). Conclusion: MRI could be helpful in distinguishing lipomatous tumors, allowing biopsy to be avoided in some cases (negative predictive value=100%)

Menstrual pattern and menstrual disorders among adolescents: an update of the Italian data.

Abstract Background The most striking event in the whole process of female puberty is the onset of menstruation. To our knowledge, no large population-based studies have been performed on the topic of menstrual health among Italian adolescents in recent years. The aims of this study were to produce up-to-date information on the menstrual pattern of Italian girls attending secondary school, and to estimate the prevalence of menstrual cycle abnormalities in this population. Methods This was a cross-sectional study on a population-based sample of Italian adolescents aged 13–21 years attending secondary school. Only girls who had already started menstruating were requested to participate. Information was collected by means of a questionnaire that included items on the girls’ demographic details, anthropometrics, smoking and drinking habits, use of contraceptive pills, and socioeconomic status. The questions on the girls’ menstrual pattern concerned their age at menarche, duration of the most recent menstruation intervals (35 days, variable), average days of bleeding (6 days), and any menstrual problems and their frequency. Results A total of 6,924 questionnaires were administered and 4,992 (71%) were returned. One hundred girls failed to report their date of birth, so 4,892 subjects were analyzed. The girls’ mean age was 17.1 years (SD ±1.4); their mean age at menarche was 12.4 (±1.3) years, median 12.4 years (95%CI 12.3–12.5). In our sample population, 3.0% (95%CI 2.5%-3.4%) of the girls had menstruation intervals of less than 21 days, while it was more than 35 days in 3.4% (95%CI 2.9%-3.9%). About 9% of the girls (95%CI 7.7%-9.4%) said the length of their menstruation interval was currently irregular. Short bleeding periods (6 days) in 19% (95%CI 17.9%-20.1%). Menstruation-related abdominal pain was reported by about 56% of our sample. About 6.2% of the girls (95%CI 5.4%-7.0%) were suffering from dysmenorrhea. Conclusions In conclusion, to the best of our knowledge, this is one of the largest studies on menstrual patterns and menstrual disorders among Italian adolescent girls. Adolescent girls referring persistent oligomenorrhoea, in first two years from menarche, had a higher risk for developing a persistent menstrual irregularity. They had longer bleeding periods (>6 days) and this has practical implications because it makes these adolescents potentially more susceptible to iron deficiency anemia. Clinicians need to identify menstrual abnormalities as early as possible in order to minimize their possible consequences and sequelae, and to promote proper health information. We recommend that adolescents should be encouraged to chart their menstrual frequency and regularity prospectively from the menarche onwards.</p