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Premovement inhibition can protect motor actions from interference by response‐irrelevant sensory stimulation
No full textShortly before movement initiation, the corticospinal system undergoes a transient suppression. This phenomenon has been observed across a range of motor tasks, suggesting that it may be an obligatory component of movement preparation. We probed whether this was also the case when the urgency to perform a motor action was high, in a situation where little time was available to engage in preparatory processes. We controlled the urgency of an impending motor action by increasing or decreasing the foreperiod duration in an anticipatory timing task. Transcranial magnetic stimulation (TMS; experiment 1) or a loud acoustic stimulus (LAS; experiment 2) were used to examine how corticospinal and subcortical excitability were modulated during motor preparation. Preparatory inhibition of the corticospinal tract was absent when movement urgency was high, though motor actions were initiated on time. In contrast, subcortical circuits were progressively inhibited as the time to prepare increased. Interestingly, movement force and vigour were reduced by both TMS and the LAS when movement urgency was high, and enhanced when movement urgency was low. These findings indicate that preparatory inhibition may not be an obligatory component of motor preparation. The behavioural effects we observed in the absence of preparatory inhibition were induced by both TMS and the LAS, suggesting that accessory sensory stimulation may disrupt motor output when such stimulation is presented in the absence of preparatory inhibition. We conclude that preparatory inhibition may be an adaptive strategy which can serve to protect the prepared motor action from external interference
The complete mitochondrial genome of the Australian ghost bat Macroderma gigas
Get PDFThe Ghost bat Macroderma gigas is a monotypic bat species that is endemic to northern Australia and named on the basis of the large size of its partially conjoined ears. It is the only carnivorous bat found in Australia and its conservation status is currently listed as Vulnerable. Here, we describe the complete mitochondrial genome of M. gigas and compare it to other vertebrates. The M. gigas circularized mitogenome was 16,661 bp and contained 13 protein-coding genes, two rRNA genes, 22 tRNAs and a control region (D-loop) of 1228 bp. Phylogenetic analysis of available entire mitogenomes reveals that Macroderma gigas is most closely related to the Indian false vampire bat Megaderma lyra in the family Megadermatidae (false vampire bats)
Tilapia from most of the sources in Bangladesh are safe for human consumption: A Hazard Index (HI) based study on heavy metals
No full textThe present study was conducted to determine the variations of heavy metal (Cu, Pb, Ni, Cr, Cd, and Zn) bioaccumulation in edible muscles among the wild, pond-, gher- and cage-cultured tilapia, followed by risk assessment in humans caused by consumption of the contaminated fish. A total of 120 fishes from four different aquatic environments were collected, and the heavy metal levels were analyzed using an atomic absorption spectrophotometer (AAS). The result found the highest Zn concentration in all tilapia samples; however, the Ni was below the detection limit. The average concentrations of metals were found as Zn > Pb > Cr > Cu in wild tilapia, Zn > Pb > Cr > Cu > Cd in pond-cultured tilapia, Zn > Pb > Cr > Cd in gher-cultured tilapia, and Zn > Cd > Cr > Pb > Cu in cage-cultured tilapia. The estimated daily intake (EDI) value was lower than the maximum tolerable daily intake value, and target hazard quotient (THQ) and hazard index (HI) for adults, adolescent, and children was < 1 for wild and cultured tilapia, indicating that tilapia is safe for human consumption. However, high HI of Pb and Cd might be alarming and need further investigation in the near future
Fungal Planet description sheets: 1182–1283
Get PDFNovel species of fungi described in this study include those from various countries as follows: Algeria, Phaeoacremonium adelophialidum from Vitis vinifera. Antarctica, Comoclathris antarctica from soil. Australia, Coniochaeta salicifolia as endophyte from healthy leaves of Geijera salicifolia, Eremothecium peggii in fruit of Citrus australis, Microdochium ratticaudae from stem of Sporobolus natalensis, Neocelosporium corymbiae on stems of Corymbia variegata, Phytophthora kelmanii from rhizosphere soil of Ptilotus pyramidatus, Pseudosydowia backhousiae on living leaves of Backhousia citriodora, Pseudosydowia indoor oopillyensis, Pseudosydowia louisecottisiae and Pseudosydowia queenslandica on living leaves of Eucalyptus sp. Brazil, Absidia montepascoalis from soil. Chile, Ilyonectria zarorii from soil under Maytenus boaria. Costa Rica, Colletotrichum filicis from an unidentified fern. Croatia, Mollisia endogranulata on deteriorated hardwood. Czech Republic, Arcopilus navicularis from tea bag with fruit tea, Neosetophoma buxi as endophyte from Buxus sempervirens, Xerochrysium bohemicum on surface of biscuits with chocolate glaze and filled with jam. France, Entoloma cyaneobasale on basic to calcareous soil, Fusarium aconidiale from Triticum aestivum, Fusarium juglandicola from buds of Juglans regia. Germany, Tetraploa endophytica as endophyte from Microthlaspi perfoliatum roots. India, Castanediella ambae on leaves of Mangifera indica, Lactifluus kanadii on soil under Castanopsis sp., Penicillium uttarakhandense from soil. Italy, Penicillium ferraniaense from compost. Namibia, Bezerromyces gobabebensis on leaves of unidentified succulent, Cladosporium stipagrostidicola on leaves of Stipagrostis sp., Cymostachys euphorbiae on leaves of Euphorbia sp., Deniquelata hypolithi from hypolith under a rock, Hysterobrevium walvisbayicola on leaves of unidentified tree, Knufia hypolithi and Knufia walvisbayicola from hypolith under a rock, Lapidomyces stipagrostidicola on leaves of Stipagrostis sp., Nothophaeotheca mirabibensis (incl. Nothophaeotheca gen. nov.) on persistent inflorescence remains of Blepharis obmitrata, Paramyrothecium salvadorae on twigs of Salvadora persica, Preussia procaviicola on dung of Procavia sp., Sordaria equicola on zebra dung, Volutella salvadorae on stems of Salvadora persica. Netherlands, Entoloma ammophilum on sandy soil, Entoloma pseudocruentatum on nutrient poor(acid)soil, Entoloma pudens on plant debris, amongst grasses. New Zealand, Amorocoelophoma neoregeliae from leaf spots of Neoregelia sp., Aquilomyces metrosideri and Septoriella callistemonis from stem discolouration and leaf spots of Metrosideros sp., Cadophora neoregeliae from leaf spots of Neoregelia sp., Flexuomyces asteliae (incl. Flexuomyces gen. nov.) and Mollisia asteliae from leaf spots of Astelia chathamica, Ophioceras freycinetiae from leaf spots of Freycinetia banksii, Phaeosphaeria caricis-sectae from leaf spots of Carex secta. Norway, Cuphophyllus flavipesoides on soil in semi-natural grassland, Entoloma coracis on soil in calcareous Pinus and Tilia forests, Entoloma cyaneolilacinum on soil semi-natural grasslands, Inocybe norvegica on gravelly soil. Pakistan, Butyriboletus parachinarensis on soil in association with Quercus baloot. Poland, Hyalodendriella bialowiezensis on debris beneath fallen bark of Norway spruce Picea abies. Russia, Bolbitius sibiricus on a moss covered rotting trunk of Populus tremula, Crepidotus wasseri on debris of Populus tremula, Entoloma isborscanum on soil on calcareous grasslands, Entoloma subcoracis on soil in subalpine grasslands, Hydropus lecythiocystis on rotted wood of Betula pendula, Meruliopsis faginea on fallen dead branches of Fagus orientalis, Metschnikowia taurica from fruits of Ziziphus jujube, Suillus praetermissus on soil, Teunia lichenophila as endophyte from Cladonia rangiferina. Slovakia, Hygrocybe fulgens on mowed grassland, Pleuroflammula pannonica from corticated branches of Quercus sp. South Africa, Acrodontium burrowsianum on leaves of unidentified Poaceae, Castanediella senegaliae on dead pods of Senegalia ataxacantha, Cladophialophora behniae on leaves of Behnia sp., Colletotrichum cliviigenum on leaves of Clivia sp., Diatrype dalbergiae on bark of Dalbergia armata, Falcocladium heteropyxidicola on leaves of Heteropyxis canescens, Lapidomyces aloidendricola as epiphyte on brown stem of Aloidendron dichotomum, Lasionectria sansevieriae and Phaeosphaeriopsis sansevieriae on leaves of Sansevieria hyacinthoides, Lylea dalbergiae on Diatrype dalbergiae on bark of Dalbergia armata, Neochaetothyrina syzygii (incl. Neochaetothyrina gen. nov.) on leaves of Syzygium chordatum, Nothophaeomoniella ekebergiae (incl. Nothophaeomoniella gen. nov.) on leaves of Ekebergia pterophylla, Paracymostachys euphorbiae (incl. Paracymostachys gen. nov.)on leaf litter of Euphorbia ingens, Paramycosphaerella pterocarpi on leaves of Pterocarpus angolensis, Paramycosphaerella syzygii on leaf litter of Syzygium chordatum, Parateichospora phoenicicola (incl. Parateichospora gen. nov.)on leaves of Phoenix reclinata, Seiridium syzygii on twigs of Syzygium chordatum, Setophoma syzygii on leaves of Syzygium sp., Starmerella xylocopis from larval feed of an Afrotropical bee Xylocopa caffra, Teratosphaeria combreti on leaf litter of Combretum kraussii, Teratosphaericola leucadendri on leaves of Leucadendron sp., Toxicocladosporium pterocarpi on pods of Pterocarpus angolensis. Spain, Cortinarius bonachei with Quercus ilex in calcareus soils, Cortinarius brunneovolvatus under Quercus ilex subsp. ballota in calcareous soil, Extremopsis radicicola (incl. Extremopsis gen. nov.) from root-associated soil in a wet heathland, Russula quintanensis on acidic soils, Tubaria vulcanica on volcanic lapilii material, Tuber zambonelliae in calcareus soil. Sweden, Elaphomyces borealis on soil under Pinus sylvestris and Betula pubescens. Tanzania, Curvularia tanzanica on inflorescence of Cyperus aromaticus. Thailand, Simplicillium niveum on Ophiocordyceps camponoti-leonardi on under side of unidentified dicotyledonous leaf. USA, Calonectria californiensis on leaves of Umbellularia californica, Exophiala spartinae from surface sterilised roots of Spartina alterniflora, Neophaeococcomyces oklahomaensis from outside wall of alcohol distillery. Vietnam, Fistulinella aurantioflava on soil. Morphological and culture characteristics are supported by DNA barcodes
Environmental DNA provides higher resolution assessment of riverine biodiversity and ecosystem function via spatio-temporal nestedness and turnover partitioning
Get PDFRapidly assessing biodiversity is essential for environmental monitoring; however, traditional approaches are limited in the scope needed for most ecological systems. Environmental DNA (eDNA) based assessment offers enhanced scope for assessing biodiversity, while also increasing sampling efficiency and reducing processing time, compared to traditional methods. Here we investigated the effects of landuse and seasonality on headwater community richness and functional diversity, via spatio-temporal dynamics, using both eDNA and traditional sampling. We found that eDNA provided greater resolution in assessing biodiversity dynamics in time and space, compared to traditional sampling. Community richness was seasonally linked, peaking in spring and summer, with temporal turnover having a greater effect on community composition compared to localized nestedness. Overall, our assessment of ecosystem function shows that community formation is driven by regional resource availability, implying regional management requirements should be considered. Our findings show that eDNA based ecological assessment is a powerful, rapid and effective assessment strategy that enables complex spatio-temporal studies of community diversity and ecosystem function, previously infeasible using traditional methods
Generation of a novel SARS-CoV-2 sub-genomic RNA due to the R203K/G204R variant in nucleocapsid: homologous recombination has potential to change SARS-CoV-2 at both protein and RNA level
Get PDFBackground Genetic variations across the SARS-CoV-2 genome may influence transmissibility of the virus and the host’s anti-viral immune response, in turn affecting the frequency of variants over-time. In this study, we examined the adjacent amino acid polymorphisms in the nucleocapsid (R203K/G204R) of SARS-CoV-2 that arose on the background of the spike D614G change and describe how strains harboring these changes became dominant circulating strains globally.
Methods Deep sequencing data of SARS-CoV-2 from public databases and from clinical samples were analyzed to identify and map genetic variants and sub-genomic RNA transcripts across the genome.
Results Sequence analysis suggests that the three adjacent nucleotide changes that result in the K203/R204 variant have arisen by homologous recombination from the core sequence (CS) of the leader transcription-regulating sequence (TRS) rather than by stepwise mutation. The resulting sequence changes generate a novel sub-genomic RNA transcript for the C-terminal dimerization domain of nucleocapsid. Deep sequencing data from 981 clinical samples confirmed the presence of the novel TRS-CS-dimerization domain RNA in individuals with the K203/R204 variant. Quantification of sub-genomic RNA indicates that viruses with the K203/R204 variant may also have increased expression of sub-genomic RNA from other open reading frames.
Conclusions The finding that homologous recombination from the TRS may have occurred since the introduction of SARS-CoV-2 in humans resulting in both coding changes and novel sub-genomic RNA transcripts suggests this as a mechanism for diversification and adaptation within its new host
Residents' perceptions toward socio-cultural issues in regional tourism development in Anambra and Enugu States of Southeastern Nigeria
Get PDFResearch on residents’ perceptions of the socio-cultural issues in tourism development in Southeastern Nigeria are limited. Drawing from collaboration and responsible tourism frameworks, this thesis explores residents’ perceptions of tourism impacts; the resources that could be harnessed; and how to support the responsible development of tourism in the region. Southeastern Nigeria is home to the Igbo tribe, comprising Abia, Anambra, Ebonyi, Enugu and Imo. The thesis focuses on selected clans in Anambra and Enugu States. The discussions are presented from an emic perspective because I am a member of the Igbo society, have acquired western knowledge and am involved in tourism education.
This research adopts a qualitative design, and takes an ethnographic approach to understand how participants construct knowledge about socio-cultural issues associated with regional tourism development. Using a purposive sampling technique targeted at people in key positions 216 tourism stakeholders including traditional rulers, men, women and youth representatives, chief priests, security agents and tourism officials were identified to take part in interviews and focus group discussions. Data were analyzed using qualitative content analysis.
The analysis identified five categories that influenced residents’ perceptions of tourism issues (governance, tourism, religion, community and culture/gender-related attributes). The results showed that whilst tourism is in the exploratory stage, it remains a perceived strategy for community development and cultural revival. The findings also indicated that neo-colonialism, Christianity and culture influence how residents perceived tourism in the area. Some strategies are discussed for addressing the challenges, such as glocalization, decentralizing tourism planning and genuine stakeholder collaboration.
The results highlighted issues and strategies that could inform developers on gaining and improving residents’ perceptions in the region. The study confirmed that residents’ perceptions are influenced by destination-specific factors, such as neo-colonialism, the newness of tourism, religion and culture in the Igbo society. Further research is needed to highlight other factors that influence how residents perceive tourism impacts.
Keywords: Tourism development, Southeastern Nigeria, socio-cultural impacts, responsible tourism, stakeholder collaboration, community participatio
A rare capture of two Japanese rubyfish (Erythrocles schlegelii) (Richardson, 1846) off southern Western Australia, including their otolith characteristics and age
No full textDue to advances in fish-finding equipment and vessel capabilities, commercial and recreational fishers are now regularly accessing deep waters off the edge of the continental shelf and catching fish species that are rarely encountered in shallower waters or that have not previously been caught. This study details the capture of two Japanese rubyfish (Erythrocles schlegelii) in deep, offshore waters on the south coast of Western Australia, and in waters further south than previously encountered. This study also provides the first age estimates from counts of growth (opaque) zones in sectioned sagittal otoliths. The estimated ages of 8 years for both individuals, one female and the other male, are much lower than what would have been expected based on age estimates for this species derived from scales undertaken in an earlier study. Understanding the biological characteristics of these deepwater fish species will assist in future management of these resources
Swordplay: Lord Mountbatten, Count Terauchi and the Japanese surrender in Southeast Asia
No full textField Marshal Count Terauchi’s personal surrender of swords to Admiral Lord Louis Mountbatten in November 1945 highlights some of the complexities related to the Japanese surrender in Southeast Asia. Japanese swords served as important symbols for both their owners and the Allies. Mountbatten’s determination to dispossess the Japanese of their swords reflected his views on Japan’s militarism and a desire to impress upon soldiers their subservience to British authority when most had not been directly defeated in battle. On the other hand, Mountbatten was constrained by the huge area placed under his command, the lack of resources at his disposal and rising nationalist resistance. In these circumstances, Mountbatten sought the co-operation of surrendered Japanese personnel in British interests. The issue of surrendering Japanese swords underlines Mountbatten’s conflicting objectives and Count Terauchi’s efforts to manipulate the situation
Feasibility assessment of Kian-I mobile robot for autonomous navigation
No full textA two-wheeled mobile robot, namely Kian-I, is designed and prototyped in this research. The Kian-I is comparable with Khepera-IV in terms of dimensional specifications, mounted sensors, and performance capabilities and can be used for educational purposes and cost-effective experimental tests. A motion control architecture is designed for Kian-I in this study to facilitate accurate navigation for the robot in an immersive environment. The implemented control structure consists of two main components of the path recommender system and trajectory tracking controller. Given partial knowledge about the operation field, the path recommender system adopts B-spline curves and particle swarm optimization algorithm to determine a collision-free path curve with translational velocity constraint. The provided optimal reference path feeds into the trajectory tracking controller enabling Kian-I to navigate autonomously in the operating field. The trajectory tracking module eliminates the error between the desired path and the followed trajectory through controlling the wheels’ velocity. To assess the feasibility of the proposed control architecture, the performance of Kian-I robot in autonomous navigation from any arbitrary initial pose to a target of interest is evaluated through numerous simulation and experimental studies. The experimental results demonstrate the functional capacities and performance of the prototyped robot to be used as a benchmark for investigation and verification of various mobile robot algorithms in the laboratory environment