A 212-nt long RNA structure in the Tobacco necrosis virus-D RNA genome is resistant to Xrn degradation

Plus-strand RNA viruses can accumulate viral RNA degradation products during infections. Some of these decay intermediates are generated by the cytosolic 5′-to-3′ exoribonuclease Xrn1 (mammals and yeast) or Xrn4 (plants) and are formed when the enzyme stalls on substrate RNAs upon encountering inhibitory RNA structures. Many Xrn-generated RNAs correspond to 3′-terminal segments within the 3′-UTR of viral genomes and perform important functions during infections. Here we have investigated a 3′-terminal small viral RNA (svRNA) generated by Xrn during infections with Tobacco necrosis virus-D (family Tombusviridae). Our results indicate that (i) unlike known stalling RNA structures that are compact and modular, the TNV-D structure encompasses the entire 212 nt of the svRNA and is not functionally transposable, (ii) at least two tertiary interactions within the RNA structure are required for effective Xrn blocking and (iii) most of the svRNA generated in infections is derived from viral polymerase-generated subgenomic mRNA1. In vitro and in vivo analyses allowed for inferences on roles for the svRNA. Our findings provide a new and distinct addition to the growing list of Xrn-resistant viral RNAs and stalling structures found associated with different plant and animal RNA viruses.York University Librarie

Temporal artery biopsies: Are we taking long enough specimens?

Mesura 4,40 x 1,10 x 1,10 metres.Arnau Mascort, EusebiPla general de l'escultura a plaça Catalunya .Elogi a la navegació, fou realitzada amb pedra de Montjuïc, la figura mesura 2,90 x 1,08 x 0,90 metres

Diversity and richness of ant species in a lowland wet forest reserve in Sri Lanka

Sinharaja Forest Reserve (SFR) represents one of the largest remaining stands of mixed dipterocarp forest in southwestern Sri Lanka. It is characterised by high floral and faunal endemicity and is gazetted as a World Heritage Site. Research was undertaken to study the ground-dwelling ants in the SFR using pitfall traps and leaf litter extraction. The collection was carried out in disturbed and undisturbed primary forest, old selectively-logged forest (30 years old) and periphery forest (agricultural buffer zone) along a small elevation gradient (200 m – 700 m). A total of 173 species and morphospecies in 11 subfamilies and 54 genera were caught. Pheidole and Tetramorium were the most speciose genera, with 19 and 18 species respectively; Cerapachys followed with 12 species. These results demonstrate the high diversity of litter dwelling ant species in the SFR. There were no significant differences in species richness between sites within the forest. Future studies should analyse species assemblages in each forest type in relation to forest structure and environmental parameters to further understand the distribution of ant species across this unique and complex forest

A new species of Neocaeculus (Acari: Prostigmata: Caeculidae) from Barrow island, Western Australia, with a checklist of world Caeculidae

Neocaeculus imperfectus new species is described from material collected on Barrow Island, Western Australia. Keys to genera and Australasian species of Caeculidae are provided, and the relationship between the genera Neocaeculus and Microcaeculus is discussed. A checklist of species for Caeculidae is provided

Why the Utilization of E-Government Services is Poor? – A study with the Citizens in Colombo Municipal Council Area in Sri Lanka

One of the most important elements of an e-Government system is the interaction between users and e-Government systems, specifically the adoption and utilization by those users, who are the main target of such systems. However, even after taken numerous efforts to develop an e-service system in Sri Lanka, its utilization and adoption are still at a very poor level. It indicates as the rate of online submission of applications is 1.16% and for license/ permits it is 0.18%. Thus, this research aims to investigate, analyze and understand the key factors that influence users’ adoption and utilization of two e-Government services: e-Vehicle revenue license and e-Police clearance certificate in Sri Lanka with a holistic approach. The conceptual framework was developed by studying the Technology Acceptance Model (TAM) and Web Trust models and theories related to technology acceptance and usage, in conjunction with a review of e-Government adoption and utilization literature. The study population was the Colombo Municipal Council area with 561,314 individuals. A random sample of 203 chief occupants was selected and the response rate was 96.5%. Respondents’ demographic details, educational qualifications, internet experience, e-Government usage and as well as preferences when obtaining e-Government services were included.  The results showed significant (5% level) moderate positive relationships among utilization and “usefulness”, “ease of use”, “trust in the internet” and “trust in the Government”. Moreover, “usefulness” (β=0.445) and “trust of the government” (β=0.379) were found to be the significant (5% level) influential factors in adoption and utilization with model adequacy at 36.5%. Similar to the literature, the findings ensure that when the usefulness and the trust are at a higher level, the adoption and utilization also be at a higher level. The-  challenges for citizen-centered e-Government applications were identified as a lack of users’ trust in the internet service providers, level of security standards, quality of e-Government systems, reluctance to share, exchange, and store their personal information specially the financial information in the online platform. However, the positive factor is the citizens perceive and experience e-Government systems as simple to use and useful. Further, they intend to accept and use it. Based on the interviews held with the uses, implementing simple and useful e-services and e-transactions, enhancing the reliability of the services, improving the accessibility options of the implemented e-services and e-transactions, and increasing the awareness of implemented e-services and their benefits were highlighted as their suggestions to develop the existing e-Government systems and services in Sri Lanka. The most important fact emphasized here is the implementation of a one-stop e-Government portal for all the services. Actions taken to enhance the digital literacy of the citizens from their school level will be benefited to successful adoption and utilization of e-services in Sri Lanka

A revision of the ant genus Probolomyrmex (Hymenoptera: Formicidae: Proceratiinae) in Australia and Melanesia

Five species of the rarely encountered ant genus Probolomyrmex are known from Australia and Papua New Guinea, four of which are described here for the first time. Two species belong to the greavesi species-group (P. greavesi, P. latalongus sp. n.)while three belong to the longinodus species-group (P. aliundus sp. n., P. newguinensis sp. n., P. simplex sp. n.). The genus is now known to occur broadly across northern Australia and P. newguinensis and P. simplex are the first species of the genus described from Papua New Guinea. A key to Australian and Melanesian species is provided

Sequencing the ant fauna of a small island: Can metagenomic analysis enable faster identification for routine ant surveys?

All known ant species from a small Western Australian island were subjected to DNA barcoding of the CO1 gene, with a view to using the database to identify ants by Next Generation Sequencing in subsequent, routine surveys. A further aim was to evaluate whether the data could be used to see if any new species had arrived on the island since the total fauna had been inventoried. Of the 125 unique ant species then known from the island, 72 were successfully barcoded. Those that were refractory to amplification were largely the result of sample age and/or contamination. Following this base-line barcoding, ants were sampled from 14 regular sampling sites and ant sequences were obtained from the bulked ‘metagenomic soup’. Prior to doing this, a parataxonomist had identified all ant species in the samples and returned them to the ‘soup’. Successful identification for each site varied from 38% (Sites 12 and 27) to 100% of species (Site 10). Comparison of the number of species recovered with the number of sequences obtained from each sample showed a positive correlation between the two variables. When a site had >1,000 sequences, the average recovery rate was 79%, which is in contrast to the lowest four recovery rates (Site samples 12, 22, 26 and 27), which had fewer than 440 amplicon sequences. The ability to detect individuals that occur at low frequencies is also important. We analysed each site individually to determine if a species was detected and how that related to the proportion of individuals in the pooled sample. Where a species was present at <4% of the total sample, it was only detected 10% of the time, indicating that adequate sequencing depth is critical to species recovery. We conclude that this technique was only partially successful in replacing conventional taxonomy and that it could have limited ability to detect incursions unless the new arrival is abundant. Current barcoding is no longer limited to the CO1 gene and other genes are characterised for identification of intractable groups where CO1 does not provide appropriate levels of resolution

Assessing factors influencing the spatial distribution of species diversity in ground dwelling ant assemblages in lowland, wet forest of southwest Sri Lanka

Tropical forests of the world are fast disappearing and there is a race to understand patterns of species distribution in space and time. Studying species distributions can provide better frameworks for conservation of these ecologically important patches of floral and faunal diversity. The island of Sri Lanka is a well known harbour of unique and highly threatened biodiversity. Tropical lowland forest is remnant in the south-west of the island now mainly existing in small patches. While most are small disturbed fragments, Sinharaja Forest Reserve represents one of the largest remaining patches of this important ecosystem. As a UNESCO World Heritage Site and a Man and Biosphere Reserve, it has a dual role as a conservation area and a historically important resource forest. While the distribution of vegetation diversity has been well documented, analyses of invertebrate species distributions are lacking. This thesis investigated a key arthropod group, ground dwelling ants, in relation to environmental gradients within the forest. Cumulative results demonstrate the high diversity of the forest patch. In an area representing less than half the reserve, over 173 ground dwelling ant species were found in distinct assemblages throughout the forest. Since the forest is located upon a series of parallel ridges, ant species distribution was first analysed in terms of this small elevation change. Species richness declined over a vertical incline from 430 m to 660 m, highlighting a possible small-scale, mountain mass effect. This section of the reserve is also characterised by a patch of once-logged forest (30 years previously). A study was undertaken to investigate whether there were residual effects of selective logging on the reserve.Significant differences between species assemblages in once-logged forest and unlogged forest add to growing evidence that selectively logged forests continue to remain distinct from unlogged forest even after decades of regeneration. Ant distribution was then analysed for their relationship with habitat heterogeneity and tree species distribution. Long-term research on tree species in the SFR has demonstrated a close relationship to habitat complexity. Ant species appear to respond more to the structural heterogeneity of the vegetation than to actual topographic variation within the forest. From a conservation perspective, maintaining the integrity of this highly diverse forest is imperative. The impact of anthropogenic land uses surrounding the forest was investigated in terms of ant assemblages along the forest edges. Significant differences were found between assemblages within the edges bordered by different matrix types. Even relatively large forest remnants can be affected by the surrounding matrix land uses and encouraging the growth of structurally similar vegetation and maintaining low disturbance along the borders should attenuate the effect of the edge. Overall, the highly heterogeneous distribution of ant assemblages within the SFR demonstrates the potential for other small patches to be harbours of further species diversity. Future research should be undertaken to assess the diversity and distribution of ant species within this region and encourage the protection of this remnant diversity

Investigation of the association between dietary fibre, protein and fat with Manganese content in food

Manganese deficiency may cause severe health disorders and is becoming prevalent in societies that are rapidly urbanising. Determining the Manganese contents and its relationship with the intake of protein, fibre and fats is important; which may allow people to select Manganese rich foods based on their major macronutrients. A cross-sectional study including detailed dietary assessment for two weeks, followed by proximate analysis of regularly consumed diets was conducted using 1200 adults from three different social segments as; lecturers/teachers (400), managerial employees in the private sector (400), and houses wives (400). Each social segment was assumed to elicit different lifestyles and different daily Manganese and Macronutrient intake levels. Most frequently consumed food items by them and their respective portion sizes were identified. Those were prepared using mostly practiced cooking methods and chemically analysed for proximate compositions of fat, protein, dietary fibre and Manganese contents. Regression and general liner models were used to estimate the association between protein, fibre and fat intake and Mn levels. The average daily protein, fibre and fat intakes were 53.51, 36.85 and 41.85 grams respectively. The average Manganese intake was 1.87 grams. There were significantly negative association between dietary Manganese levels and fat intake (ß=-0.041, p \u3c 0.00). Increased dietary fat intake was associated with low levels of Manganese (ß=-0.041, p \u3c 0.00) for all social segments. Higher protein (ß=0.019, p=0.01) or fibre intake (ß=0.013 p=0.002) reduced the risk of Manganese deficiency. Overall, dietary Manganese elicited a positive correlation with proteins and fibre in foods, but a negative correlation with dietary fat. © 2020 Asian Journal of Agriculture and Biology

Tombusvirids Avoid and Exploit a Plant Exoribonuclease

Tombusviridae is a family of plus-strand RNA plant viruses that contain single-stranded RNA genomes with no 5' cap or 3' poly(A) tail. The 5' cap is an essential post-transcriptional modification that increases the stability of mRNA molecules, by protecting them from 5'-to-3' exoribonuclease decay. The lack of this modification in this virus family raised the question of how these viruses protect their vulnerable genomic 5' ends from nuclease attack during infections. Carnation Italian ringspot virus (CIRV) from the genus Tombusvirus, family Tombusviridae, has a plus-strand RNA genome with a structured 5' untranslated region that I hypothesized could serve as a protective substitute for the 5' cap. Results from my in vitro and in vivo studies with CIRV showed that the higher-order RNA structure at the 5' end of its genome was able to effectively prevent access of a 5'-to-3' exoribonuclease (Xrn), thereby protecting it from being degraded by Xrn during infections. In a second related study, I investigated a small viral RNA (svRNA) that accumulated in infections with another member of the family Tombusviridae, Tobacco necrosis virus-D (TNV-D; genus Betanecrovirus). In this case, I hypothesized that the svRNA represented a stable degradation product that could be functionally relevant to successful TNV-D infections. Through in vitro and in vivo analyses of TNV-D, I determined that the svRNA was indeed generated from incomplete digestion of the TNV-D genome by Xrn, and that its accumulation was beneficial in infections. Collectively, these findings extend and broaden our knowledge of the roles of novel viral RNA structures in facilitating successful viral infections by either evading (CIRV) or exploiting (TNV-D) the activity of the cellular exoribonuclease, Xrn