Transport of Sub-micron Aerosols in Bifurcations

The convective-diffusive transport of sub-micron aerosols in an oscillatory laminar flow within a 2-D single bifurcation is studied, using order-of-magnitude analysis and numerical simulation using a commercial software (FEMLAB®). Based on the similarity between momentum and mass transfer equations, various transient mass transport regimes are classified and scaled according to Strouhal and beta numbers. Results show that the mass transfer rate is highest at the carinal ridge and there is a phase-shift in diffusive transport time if the beta number is greater than one. It is also shown that diffusive mass transfer becomes independent of the oscillating outer flow if the Strouhal number is greater than one.

Proceedings of the Ninth Annual Conference of the British Association for Biological Anthropology and Osteoarchaeology, Department of Archaeology, University of Reading

The Proceedings of the Ninth Annual Conference of the British Association for Biological Anthropology and Osteoarchaeology (BABAO) held at the University of Reading in 2007. Contents: 1) A life course perspective of growing up in medieval London: evidence of sub-adult health from St Mary Spital (London) (Rebecca Redfern and Don Walker); 2) Preservation of non-adult long bones from an almshouse cemetery in the United States dating to the late nineteenth to the early twentieth centuries (Colleen Milligan, Jessica Zotcavage and Norman Sullivan); 3) Childhood oral health: dental palaeopathology of Kellis 2, Dakhleh, Egypt. A preliminary investigation (Stephanie Shukrum and JE Molto); 4) Skeletal manifestation of non-adult scurvy from early medieval Northumbria: the Black Gate cemetery, Newcastle-upon-Tyne (Diana Mahoney-Swales and Pia Nystrom); 5) Infantile cortical hyperostosis: cases, causes and contradictions (Mary Lewis and Rebecca Gowland); 6) Biological Anthropology Tuberculosis of the hip in the Victorian Britain (Benjamin Clarke and Piers Mitchell); 7) The re-analysis of Iron Age human skeletal material from Winnall Down (Justine Tracey); 8) Can we estimate post-mortem interval from an individual body part? A field study using sus scrofa (Branka Franicevec and Robert Pastor); 9) The expression of asymmetry in hand bones from the medieval cemetery at Écija, Spain (Lisa Cashmore and Sonia Zakrezewski); 10) Returning remains: a curator’s view (Quinton Carroll); 11) Authority and decision making over British human remains: issues and challenges (Piotr Bienkowski and Malcolm Chapman); 12) Ethical dimensions of reburial, retention and repatriation of archaeological human remains: a British perspective (Simon Mays and Martin Smith); 13) The problem of provenace: inaccuracies, changes and misconceptions (Margaret Clegg); 14) Native American human remains in UK collections: implications of NAGPRA to consultation, repatriation, and policy development (Myra J Giesen); 15) Repatriation – a view from the receiving end: New Zealand (Nancy Tayles).

Application of auto regressive models of wavelet sub-bands for classifying Terahertz pulse measurements

This paper presents an approach for automatic classification of pulsed Terahertz (THz), or T-ray, signals highlighting their potential in biomedical, pharmaceutical and security applications. T-ray classification systems supply a wealth of information about test samples and make possible the discrimination of heterogeneous layers within an object. In this paper, a novel technique involving the use of Auto Regressive (AR) and Auto Regressive Moving Average (ARMA) models on the wavelet transforms of measured T-ray pulse data is presented. Two example applications are examined - the classi. cation of normal human bone (NHB) osteoblasts against human osteosarcoma (HOS) cells and the identification of six different powder samples. A variety of model types and orders are used to generate descriptive features for subsequent classification. Wavelet-based de-noising with soft threshold shrinkage is applied to the measured T-ray signals prior to modeling. For classi. cation, a simple Mahalanobis distance classi. er is used. After feature extraction, classi. cation accuracy for cancerous and normal cell types is 93%, whereas for powders, it is 98%.

Using learning networks to understand complex systems: a case study of biological, geophysical and social research in the Amazon

Developing high-quality scientific research will be most effective if research communities with diverse skills and interests are able to share information and knowledge, are aware of the major challenges across disciplines, and can exploit economies of scale to provide robust answers and better inform policy. We evaluate opportunities and challenges facing the development of a more interactive research environment by developing an interdisciplinary synthesis of research on a single geographic region. We focus on the Amazon as it is of enormous regional and global environmental importance and faces a highly uncertain future. To take stock of existing knowledge and provide a framework for analysis we present a set of mini-reviews from fourteen different areas of research, encompassing taxonomy, biodiversity, biogeography, vegetation dynamics, landscape ecology, earth-atmosphere interactions, ecosystem processes, fire, deforestation dynamics, hydrology, hunting, conservation planning, livelihoods, and payments for ecosystem services. Each review highlights the current state of knowledge and identifies research priorities, including major challenges and opportunities. We show that while substantial progress is being made across many areas of scientific research, our understanding of specific issues is often dependent on knowledge from other disciplines. Accelerating the acquisition of reliable and contextualized knowledge about the fate of complex pristine and modified ecosystems is partly dependent on our ability to exploit economies of scale in shared resources and technical expertise, recognise and make explicit interconnections and feedbacks among sub-disciplines, increase the temporal and spatial scale of existing studies, and improve the dissemination of scientific findings to policy makers and society at large. Enhancing interaction among research efforts is vital if we are to make the most of limited funds and overcome the challenges posed by addressing large-scale interdisciplinary questions. Bringing together a diverse scientific community with a single geographic focus can help increase awareness of research questions both within and among disciplines, and reveal the opportunities that may exist for advancing acquisition of reliable knowledge. This approach could be useful for a variety of globally important scientific questions.

Terahertz spectroscopy and imaging at the nanoscale for biological and security applications

The chemical specificity of terahertz spectroscopy, when combined with techniques for sub-wavelength sensing, is giving new understanding of processes occurring at the nanometre scale in biological systems and offers the potential for single molecule detection of chemical and biological agents and explosives. In addition, terahertz techniques are enabling the exploration of the fundamental behaviour of light when it interacts with nanoscale optical structures, and are being used to measure ultrafast carrier dynamics, transport and localisation in nanostructures. This chapter will explain how terahertz scale modelling can be used to explore the fundamental physics of nano-optics, it will discuss the terahertz spectroscopy of nanomaterials, terahertz near-field microscopy and other sub-wavelength techniques, and summarise recent developments in the terahertz spectroscopy and imaging of biological systems at the nanoscale. The potential of using these techniques for security applications will be considered.

Cultural phylogeography of the Bantu Languages of sub-Saharan Africa

There is disagreement about the routes taken by populations speaking Bantu languages as they expanded to cover much of sub-Saharan Africa. Here, we build phylogenetic trees of Bantu languages and map them onto geographical space in order to assess the likely pathway of expansion and test between dispersal scenarios. The results clearly support a scenario in which groups first moved south through the rainforest from a homeland somewhere near the Nigeria–Cameroon border. Emerging on the south side of the rainforest, one branch moved south and west. Another branch moved towards the Great Lakes, eventually giving rise to the monophyletic clade of East Bantu languages that inhabit East and Southeastern Africa. These phylogenies also reveal information about more general processes involved in the diversification of human populations into distinct ethnolinguistic groups. Our study reveals that Bantu languages show a latitudinal gradient in covering greater areas with increasing distance from the equator. Analyses suggest that this pattern reflects a true ecological relationship rather than merely being an artefact of shared history. The study shows how a phylogeographic approach can address questions relating to the specific histories of certain groups, as well as general cultural evolutionary processes.

Upland streamwater nitrate dynamics across decadal to sub-daily timescales: a case study of Plynlimon, Wales

Streamwater nitrate dynamics in the River Hafren, Plynlimon, mid-Wales were investigated over decadal to sub-daily timescales using a range of statistical techniques. Long-term data were derived from weekly grab samples (1984–2010) and high-frequency data from 7-hourly samples (2007–2009) both measured at two sites: a headwater stream draining moorland and a downstream site below plantation forest. This study is one of the first to analyse upland streamwater nitrate dynamics across such a wide range of timescales and report on the principal mechanisms identified. The data analysis provided no clear evidence that the long-term decline in streamwater nitrate concentrations was related to a decline in atmospheric deposition alone, because nitrogen deposition first increased and then decreased during the study period. Increased streamwater temperature and denitrification may also have contributed to the decline in stream nitrate concentrations, the former through increased N uptake rates and the latter resultant from increased dissolved organic carbon concentrations. Strong seasonal cycles, with concentration minimums in the summer, were driven by seasonal flow minimums and seasonal biological activity enhancing nitrate uptake. Complex diurnal dynamics were observed, with seasonal changes in phase and amplitude of the cycling, and the diurnal dynamics were variable along the river. At the moorland site, a regular daily cycle, with minimum concentrations in the early afternoon, corresponding with peak air temperatures, indicated the importance of instream biological processing. At the downstream site, the diurnal dynamics were a composite signal, resultant from advection, dispersion and nitrate processing in the soils of the lower catchment. The diurnal streamwater nitrate dynamics were also affected by drought conditions. Enhanced diurnal cycling in Spring 2007 was attributed to increased nitrate availability in the post-drought period as well as low flow rates and high temperatures over this period. The combination of high-frequency short-term measurements and long-term monitoring provides a powerful tool for increasing understanding of the controls of element fluxes and concentrations in surface waters.

Simple method for sub-diffraction resolution imaging of cellular structures on standard confocal microscopes by three-photon absorption of quantum dots

This study describes a simple technique that improves a recently developed 3D sub-diffraction imaging method based on three-photon absorption of commercially available quantum dots. The method combines imaging of biological samples via tri-exciton generation in quantum dots with deconvolution and spectral multiplexing, resulting in a novel approach for multi-color imaging of even thick biological samples at a 1.4 to 1.9-fold better spatial resolution. This approach is realized on a conventional confocal microscope equipped with standard continuous-wave lasers. We demonstrate the potential of multi-color tri-exciton imaging of quantum dots combined with deconvolution on viral vesicles in lentivirally transduced cells as well as intermediate filaments in three-dimensional clusters of mouse-derived neural stem cells (neurospheres) and dense microtubuli arrays in myotubes formed by stacks of differentiated C2C12 myoblasts.

The lethal and sub-lethal consequences of entomopathogenic nematode infestation and exposure for adult pine weevils, Hylobius abietis (Coleoptera: Curculionidae)

Entomopathogenic nematodes (EPN) frequently kill their host within 1–2 days, and interest in EPN focuses mainly on their lethality. However, insects may take longer to die, or may fail to die despite being infected, but little is known about the effects of EPN infection on insects, other than death. Here we investigate both lethal and sub-lethal effects of infection by two EPN species, Steinernema carpocapsae and Heterorhabditis downesi, on adults of the large pine weevil, Hylobius abietis. Following 12 h nematode–weevil contact in peat, S. carpocapsae killed a significantly higher proportion of weevils (87–93%) than H. downesi (43–57%) at all concentrations tested. Less than 10% of weevils were dead within 2 days, and weevils continued to die for up to 10 days after exposure (LT50 of 3 days or more). In a separate experiment, live weevils dissected 6 days after a 24 h exposure to nematodes on filter paper harbored encapsulated and dead nematodes, showing that weevils could defend themselves against infection. Some live weevils also harbored live nematodes 6 days after they had been removed from the nematode infested medium. Feeding by weevils was not affected by infection with, or exposure to, either species of EPN. We discuss these results in relation to the use of EPN in biological control against H. abietis.

A tellurium-based cathepsin B inhibitor: Molecular structure, modelling, molecular docking and biological evaluation

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Possible involvement of A<sub>1sub> receptors in the inhibition of gonadotropin secretion induced by adenosine in rat hemipituitaries in vitro

We investigated the participation of A<sub>1sub> or A<sub>2sub> receptors in the gonadotrope and their role in the regulation of LH and FSH secretion in adult rat hemipituitary preparations, using adenosine analogues. A dose-dependent inhibition of LH and FSH secretion was observed after the administration of graded doses of the R-isomer of phenylisopropyladenosine (R-PIA; 1 nM, 10 nM, 100 nM, 1 µM and 10 µM). The effect of R-PIA (10 nM) was blocked by the addition of 8-cyclopentyltheophylline (CPT), a selective A<sub>1sub> adenosine receptor antagonist, at the dose of 1 µM. The addition of an A<sub>2sub> receptor-specific agonist, 5-N-methylcarboxamidoadenosine (MECA), at the doses of 1 nM to 1 µM had no significant effect on LH or FSH secretion, suggesting the absence of this receptor subtype in the gonadotrope. However, a sharp inhibition of the basal secretion of these gonadotropins was observed after the administration of 10 µM MECA. This effect mimicked the inhibition induced by R-PIA, supporting the hypothesis of the presence of A<sub>1sub> receptors in the gonadotrope. R-PIA (1 nM to 1 µM) also inhibited the secretion of LH and FSH induced by phospholipase C (0.5 IU/ml) in a dose-dependent manner. These results suggest the presence of A<sub>1sub> receptors and the absence of A<sub>2sub> receptors in the gonadotrope. It is possible that the inhibition of LH and FSH secretion resulting from the activation of A<sub>1sub> receptors may have occurred independently of the increase in membrane phosphoinositide synthesis.

Adenosine A<sub>1sub> receptor-mediated inhibition of in vitro prolactin secretion from the rat anterior pituitary

In previous studies, we demonstrated biphasic purinergic effects on prolactin (PRL) secretion stimulated by an adenosine A<sub>2sub> agonist. In the present study, we investigated the role of the activation of adenosine A<sub>1sub> receptors by (R)-N6-(2-phenylisopropyl)adenosine (R-PIA) at the pituitary level in in vitro PRL secretion. Hemipituitaries (one per cuvette in five replicates) from adult male rats were incubated. Administration of R-PIA (0.001, 0.01, 0.1, 1, and 10 µM) induced a reduction of PRL secretion into the medium in a U-shaped dose-response curve. The maximal reduction was obtained with 0.1 µM R-PIA (mean ± SEM, 36.01 ± 5.53 ng/mg tissue weight (t.w.)) treatment compared to control (264.56 ± 15.46 ng/mg t.w.). R-PIA inhibition (0.01 µM = 141.97 ± 15.79 vs control = 244.77 ± 13.79 ng/mg t.w.) of PRL release was blocked by 1 µM cyclopentyltheophylline, a specific A<sub>1sub> receptor antagonist (1 µM = 212.360 ± 26.560 ng/mg t.w.), whereas cyclopentyltheophylline alone (0.01, 0.1, 1 µM) had no effect. R-PIA (0.001, 0.01, 0.1, 1 µM) produced inhibition of PRL secretion stimulated by both phospholipase C (0.5 IU/mL; 977.44 ± 76.17 ng/mg t.w.) and dibutyryl cAMP (1 mM; 415.93 ± 37.66 ng/mg t.w.) with nadir established at the dose of 0.1 µM (225.55 ± 71.42 and 201.9 ± 19.08 ng/mg t.w., respectively). Similarly, R-PIA (0.01 µM) decreased (242.00 ± 24.00 ng/mg t.w.) the PRL secretion stimulated by cholera toxin (0.5 mg/mL; 1050.00 ± 70.00 ng/mg t.w.). In contrast, R-PIA had no effect (468.00 ± 34.00 ng/mg t.w.) on PRL secretion stimulation by pertussis toxin (0.5 mg/mL; 430.00 ± 26.00 ng/mg t.w.). These results suggest that inhibition of PRL secretion after A<sub>1sub> receptor activation by R-PIA is mediated by a Gi protein-dependent mechanism.

Antioxidant capacity and biological activity of essential oil and methanol extract of Conobea scoparioides (Cham. & Schltdl.) Benth

Os óleos essenciais da planta sub-aquática Conobea scoparioides (fresca e previamente seca) apresentaram rendimentos de 3,4 e 3,3%, respectivamente. Os principais constituintes identificados foram o éter metílico do timol (39,6 e 47,7%), timol (40,0 e 26,4%), α-felandreno (12,1 e 14,3%) e p-cimeno (1,5 e 1,7%), totalizando mais de 90% nos referidos óleos. A concentração de seqüestro do radical DPPH (CE50) dos óleos e extrato foi de 46,7 ± 3,6 µg mL^-1 para a planta fresca (CsO-f), de 56,1 ± 2,4 µg mL^-1 para a planta seca (CsO-d), e de 23,0 ± 2,2 µg mL^-1 para o extrato metanólico (CsE-d). O valor do extrato é comparável ao BHT (19,8 ± 0,5 µg mL^-1), usado como padrão antioxidante. O valor médio dos óleos é duas vezes menor, mas igualmente importante como agente antioxidante. O teor de Fenólicos Totais (TP, 124,6 ± 8,7 mg GAE per g) e o Trolox Equivalente (TEAC, 144,1 ± 4,9 mg TE per g) do extrato metanólico confirmaram a significativa atividade antioxidante de C. scoparioides. Da mesma forma, nos bioensaios com larva de camarão (Artemia salina) o valor médio da concentração letal dos óleos (CL<sub>50sub>, 7,7 ± 0,3 µg mL^-1) foi dez vezes maior que no extrato metanólico (CL<sub>50sub>, 77,6 ± 7,1 µg mL^-1) mostrando importante atividade biológica.

Antioxidant capacity and biological activity of essential oil and methanol extract of Hyptis crenata Pohl ex Benth

O óleo essencial das folhas e ramos finos frescos e secos de Hyptis crenata forneceu os seguintes rendimentos, 1,4% e 0,9%. Os constituintes voláteis principais foram α-pineno (22,0%; 19,5%), 1,8-cineol (17,6%; 23,2%), β-pineno (17,0%: 13,8%), cânfora (4,7%; 11,6%), limoneno (5,4%; 4,4%) e γ-terpineno (3,5%; 2,4%), totalizando mais de 70% nos óleos. A atividade de seqüestro do radical DPPH para o extrato metanólico (CE<sub>50sub>, 16,7 + 0,4 µg/mL) foi comparável ao do BHT (19,8 ± 0,5 µg/mL) mostrando uma significante atividade antioxidante. Os óleos apresentaram baixa atividade. O teor de fenólicos totais (TP, 373,0 + 15,9 mg GAE/g) e equivalente trolox (TEAC, 226,8 + 0,5 mg TE/g) confirmaram a atividade antioxidante do extrato metanólico, que pode ser atribuída à presença de compostos fenólicos polares. No teste com larvas de camarão as concentrações letais para o óleo e extrato metanólico foram 6,7 + 0,2 µg/mL e 13,0 + 3,7 µg/mL, respectivamente, fornecendo importante evidência de suas atividade biológicas.

Variação temporal do efluxo de dióxido de carbono CO<sub>2sub> do solo em sistemas agroflorestais com palma de óleo (Elaeis guineensis) na Amazônia Oriental

A região amazônica tem sido submetida a contínuo desflorestamento e expansão do uso da terra, para a implantação de atividades como pecuária, exploração madeireira, agricultura, mineração e urbanização. A queima e a decomposição da biomassa da floresta liberam gases que contribuem para o efeito estufa, como o dióxido de carbono (CO<sub>2sub>). Nesse contexto, surge o interesse em avaliar a dinâmica do efluxo de CO<sub>2sub> do solo na Amazônia, em especial em sistemas agroflorestais de palma de óleo (Elaeis guineensis), visto o destaque da produção dessa cultura no estado do Pará, que teve uma razoável expansão, transformando o estado do Pará em um dos maiores plantadores e produtores do país. Este trabalho teve como objetivo investigar a dinâmica do efluxo de CO<sub>2sub> do solo em sistemas agroflorestais onde a palma de óleo é a cultura principal, na escala temporal e os fatores bióticos e abióticos que influenciam diretamente neste processo. Foram quantificados os carbono da biomassa microbiana do solo, carbono total do solo, respiração microbiana do solo, raízes finas do solo e zona de influência das espécies; e os fatores abióticos: umidade e temperatura do solo, em dois sistemas agroflorestais de cultivo de palma de óleo, o sistema adubadeiras e o sistema biodiverso. As medições foram feitas nos períodos seco e no chuvoso. Os resultados mostraram que o maior efluxo de CO<sub>2sub> do solo ocorreu no período chuvoso, provavelmente devido à maior atividade microbiana nesse período influenciada por fatores climáticos aliados a fatores bióticos. O sistema biodiverso apresentou maior efluxo de CO<sub>2sub> do solo do que o sistema adubadeiras, provavelmente devido à maior atividade biológica no solo nesse sistema. O efluxo de CO<sub>2sub> do solo não mostrou correlação forte com as variáveis testadas. Pôde-se concluir que o efluxo de CO<sub>2sub> do solo sofreu influencia apenas da sazonalidade climática. O fato da área de plantio ser muito jovem pode ser um fator determinante para que não tenha sido encontrada relação mais forte da respiração do solo com as variáveis analisadas.