Movements and social behaviour of the opossum, Trichosurus vulpecula KERR, in a mixed scrub, bush and pasture habitat

The movements of Australian brush-tailed opossums, Trichosurus vulpecula, were studied in a mixed bush, scrub, and pasture habitat on Banks Peninsula by live-trapping and spotlighting over a period of six months from February to July 1971. Thirty-four opossums were marked. Estimates of the size of ranges in the pasture (0.8 ha males; 0.3 ha females) were smaller than those found elsewhere, probably because of the restricted habitat. Range sizes of animals resident in the bush were considerably altered by their movements" to seasonal food sources in the pasture. Male opossums did not hold territories as described in some studies. In this mixed habitat opossums may move between scrub, bush and pasture to obtain food and shelter

Assessment of casting filling by modeling surface entrainment events using CFD

The reliability of cast components is dependent on the quality of the casting process. During this highly transient filling phase the prevention of free surface turbulence and consequential oxide entrainment is critical to ensure the mechanical integrity of the component. Past research has highlighted a number of events that lead to entrainment of surface oxides. Using FLOW-3D, flow structures that result in surface entrainment events have been simulated and an algorithm developed that allows entrainment and defect motion to be tracked. This enables prediction of the quantity and motion of oxide film generated from each event. The algorithm was tested experimentally and compared to experimental data from previously published work. A quantitative criterion is proposed to assess the damage of each type of event. Complete running systems have also been studied to understand how they could be assessed for quality of filling based on the flows within them

Organizational Innovation in Russian Agriculture: The Emergence of "New Agricultural Operators" and Its Consequences

After almost a decade of downsizing, Russian agriculture has been steadily growing since the end of 90's against the background of deep organizational changes and innovations. The traditional collective farming segment is the key target and subject of innovations. Outside investors and operators have acquired control over farm assets from the primary nominal owners and possessors. As a result, exceptionally large commercial farm operations - "agroholdings" - are being created. Both inside and outside innovators are introducing organizational changes such as vertical integration, custom and contract farming, land leasing, machinery sharing and others. The paper discusses size, scope and character of the ongoing innovations and their short and long-term consequences.agroholdings, contract and custom farming, new agricultural operators, integration, Industrial Organization,

The modelling of oxide film entrainment in casting systems using computational modelling

As Campbell stated in 2006, “the use of entrainment models to optimise filling systems designs for castings has huge commercial potential that has so far being neglected by modellers”. In this paper a methodology using computational modelling to define entraining events and track the entrained oxide films is presented. Research has shown that these oxide films present within the casting volume are highly detrimental to casting integrity, thus their entrainment during mould filling is especially undesirable. The method developed for the modelling of oxide entrainment has been validated against previously published data by Green and Campbell (1994) [31]. The validation shows good quantitative correlation with experimental data. However there is scope for further development which has the potential to both improve the accuracy and further validate the technique

Psychosocial risk and protective factors associated with perpetration of gender-based violence in a community sample of men in rural KwaZulu-Natal, South Africa

Background. Rates of gender-based violence (GBV) in South Africa (SA) are among the highest in the world. In societies where social ideals of masculinity encourage male dominance and control over women, gender power imbalances contribute to male perpetration and women’s vulnerability. The drivers that cause men to perpetrate GBV and those that lead to HIV overlap and interact in multiple and complex ways. Multiple risk and protective factors for GBV perpetration by males operate interdependently at a number of levels; at the individual level, these include chronic anxiety and depression, which have been shown to lead to risky sexual behaviours.Objectives. (i) To examine psychosocial risk factors (symptoms of anxiety and depression) as well as protective factors (social support and self-esteem) as self-reported by a cohort of males in rural KwaZulu-Natal (KZN) Province, SA; and (ii) to determine whether there are differences in anxiety, depression, social support and self-esteem between perpetrators and non-perpetrators.Methods. A cross-sectional study using quasi-probability cluster sampling of 13 of 28 wards in Harry Gwala District, KZN. Participants were then randomly chosen from each ward proportionate to size.Results. The participants were relatively young (median age 22 years); over half were schoolgoers, and 91.3% had never married. Over 43% of the sample reported clinical levels of anxiety and depressive symptoms on the Brief Symptom Inventory. Rates of GBV perpetration were 60.9%, 23.6% and 10.0% for psychological abuse, non-sexual physical violence and sexual violence, respectively. GBV perpetration was associated with higher depression, higher anxiety, lower self-esteem and lower social support.Conclusions. Interventions to address GBV need to take modifiable individual-level factors into account

Priprava i vrednovanje matriksnog agensa na bazi ispagule za kontrolirano oslobađanje

The objective of the present investigation was to prepare and evaluate an ispaghula husk based directly compressible (DC) adjuvant that can be used as matrixing agent using an agglomeration technique. Addition of hydroxylpropyl methylcellulose was found necessary to improve cohesion. Lactose (X1), calcium hydrogen phosphate diydrate (X2) and Avicel PH101 (X3), used along with ispaghula in preparation of agglomerates, were selected as three independent variables in a simplex lattice design affecting compressional and dissolution characteristics of the drug from the DC adjuvant. The agglomerates were evaluated for their flow properties. Tablets were prepared using 70% agglomerates and 30% acetaminophen, a poorly compressible drug, and were subjected to the in vitro drug release study. Amounts of the drug released at the end of 60 min (Y60), 300 min (Y300) and 480 min (Y480) were selected as dependent variables in a simplex lattice design. Batch IH05 that contained lactose and calcium hydrogen phosphate dihydrate in a 1:2 ratio could control the release for 12 hours and thus form the basis for twice-a-day dosing.Cilj rada bio je priprava i vrednovanje pomoćne tvari za izravnu kompresiju dobivene iz ljuski ispagule, primjenjive u izradi pripravaka metodom aglomeracije. Dodatak hidroksipropil metilceluloze bio je neophodan za povećanje kohezije. U pripravi aglomerata s ispagulom upotrebljeni su laktoza (X1), kalcijev hidrogenfosfat dihidrat (X2) i Avicel PH101 (X3). U eksperimentalnom dizajnu (simplex lattice design) te tri tvari izabrane su kao nezavisne varijable. Proučavan je njihov utjecaj na kompresibilnost i oslobađanje ljekovite tvari iz pripravka dobivenih izravnom kompresijom te svojstva tečnosti aglomerata. Tako dobiveni aglomerati upotrebljeni su za pripravu tableta teško kompresibilne tvari acetaminofena (omjer aglomerata i ljekovite tvari 7:3). Količine oslobođene tvari in vitro pri kraju 60 min (Y60), 300 min (Y300) i 480 min (Y480) bils su zavisne varijable. Iz pripravka IH05 koji sadrži laktozu i kalcijev hidrogenfosfat dihidrat u omjeru 1:2 kontrolirano se oslobađa ljekovita tvar tijekom 12 sati, što je dobar temelj za doziranje dva puta dnevno

Quantifying cancer epithelial-mesenchymal plasticity and its association with stemness and immune response

Cancer cells can acquire a spectrum of stable hybrid epithelial/mesenchymal (E/M) states during epithelial-mesenchymal transition (EMT). Cells in these hybrid E/M phenotypes often combine epithelial and mesenchymal features and tend to migrate collectively commonly as small clusters. Such collectively migrating cancer cells play a pivotal role in seeding metastases and their presence in cancer patients indicates an adverse prognostic factor. Moreover, cancer cells in hybrid E/M phenotypes tend to be more associated with stemness which endows them with tumor-initiation ability and therapy resistance. Most recently, cells undergoing EMT have been shown to promote immune suppression for better survival. A systematic understanding of the emergence of hybrid E/M phenotypes and the connection of EMT with stemness and immune suppression would contribute to more effective therapeutic strategies. In this review, we first discuss recent efforts combining theoretical and experimental approaches to elucidate mechanisms underlying EMT multi-stability (i.e. the existence of multiple stable phenotypes during EMT) and the properties of hybrid E/M phenotypes. Following we discuss non-cell-autonomous regulation of EMT by cell cooperation and extracellular matrix. Afterwards, we discuss various metrics that can be used to quantify EMT spectrum. We further describe possible mechanisms underlying the formation of clusters of circulating tumor cells. Last but not least, we summarize recent systems biology analysis of the role of EMT in the acquisition of stemness and immune suppression.Comment: 50 pages, 6 figure

Cercarial Transformation and in vitro Cultivation of Schistosoma mansoni Schistosomules

Schistosome parasites are the causative agents of schistosomiasis, a chronically debilitating disease that affects over 200 million people globally and ranks second to malaria among parasitic diseases in terms of public health and socio-economic impact (1-4). Schistosome parasites are trematode worms with a complex life cycle interchanging between a parasitic life in molluscan and mammalian hosts with intervening free-swimming stages. Briefly, free-swimming cercariae infect a mammalian host by penetrating the skin with the aid of secreted proteases, during which time the cercariae lose their tails, transforming into schistosomules. The schistosomules must now evade the host immune system, develop a gut for digestion of red blood cells, and migrate though the lungs and portal circulation en route to their final destination in the hepatic portal system and eventually the mesenteric veins (for S. mansoni) where male and female worms pair and mate, producing hundreds of eggs daily. Some of the eggs are excreted from the body into fresh water, where the eggs hatch into free-swimming miracidia (5-10). The miracidia infect specific snail species and transform into mother and daughter sporocysts, which in turn, produce infective cercariae, completing the life cycle. Unfortunately, the entire schistosome life cycle cannot be cultured in vitro, but infective cercariae can be transformed into schistosomules, and the schistosomules can be cultured for weeks for the analysis of schistosome development in vitro or microarray analysis. In this protocol, we provide a visual description of cercarial transformation and in vitro culturing of schistosomules. We shed infectious cercariae from the snail host Biomphalaria glabrata and manually transform them into schistosomules by detaching their tails using an emulsifying double-ended needle. The in vitro cercarial transformation and schistosomules culture techniques described avoid the use of a mammalian host, which simplifies visualization of schistosomes and facilitates the collection of the parasite for experimental analysis. in vitro transformation and culturing techniques of schistosomes have been done for years (11, 12), but no visual protocols have been developed that are available to the entire community