Publications by authors named "Jenna Ross"

Article Synopsis
  • Two new strains of ammonia-oxidising archaea were isolated from acidic soils in the UK and China, showing over 99% genetic similarity but distinct physiological features.
  • Both strains, Nd1 and Nd2, are non-motile chemolithotrophs that oxidize ammonia to gain energy, but cannot use urea as an ammonia source.
  • The strains were classified into a new genus, with Nd1 and Nd2 designated as type strains for new species, alongside the proposal of a new family and order.
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Article Synopsis
  • Species that move north due to human-induced changes likely face less diverse communities, which might lead to less competition and predation, allowing them more opportunities in their new habitats.
  • The study focused on oak gall wasps, particularly Neuroterus saltatorius, across a range from northern California to Vancouver Island, identifying 23 types of wasps and examining how their diversity followed a latitudinal gradient.
  • Results showed that diversity of gall wasps decreased at higher latitudes, with fewer interactions observed among wasps in northern areas, suggesting that these low diversity settings could provide a competitive advantage for expanding species.
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Terrestrial gastropod molluscs (slugs and snails) (Mollusca: Gastropoda) cause significant crop damage around the world. There is no formal approach for differentiating between slugs and snails; however, an organism is usually considered a slug when there is no external shell, or when the shell is small in comparison to the body, and a snail when there is a large external shell. Although snails are an important pest of many crops, this review focuses on slug pests and their nonchemical control measures.

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Biological control (biocontrol) as a component of pest management strategies reduces reliance on synthetic chemicals, and seemingly offers a natural approach that minimizes environmental impact. However, introducing a new organism to new environments as a classical biocontrol agent can have broad and unanticipated biodiversity effects and conservation consequences. Nematodes are currently used in a variety of commercial biocontrol applications, including the use of Phasmarhabditis hermaphrodita as an agent targeting pest slug and snail species.

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Baitchain is a novel molluscicide system that consists of metaldehyde pellets arranged on a cord and is designed to be tied around the base of tree trunks and act as a physical and chemical control method for molluscs. In this study, Baitchain is tested in a South African apple orchard and compared with traditional metaldehyde pellets (Sluggit) applied to the soil surface to determine the efficacy of the products against the brown garden snail, (Helicidae). The products were applied at two different concentrations, including 15 g/kg (Baitchain 15 and Sluggit 15) and 40 g/kg (Baitchain 40 and Sluggit 40) metaldehyde, and the products were either applied on their own, or in combination.

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During a survey for mollusc-associated nematodes in South Africa, a new Phasmarhabditis species was isolated from the invasive slug, Deroceras reticulatum, collected from a nursery near George in the Western Cape province. The nematode was identified using a combination of morphological, morphometric, molecular, and phylogenetic techniques. The new species, P.

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Aims: During pregnancy, there is a significant increase in heart rate (HR) potentially associated with an increased risk of arrhythmias or exacerbation of pre-existing cardiac conditions endangering both mother and foetus. Calcium homeostasis plays an important role in regulating automaticity of the sinoatrial node (SAN); however, its contribution to the accelerated HR during pregnancy remains unknown.

Methods And Results: Using murine SAN cells, we showed that pregnancy increased L-type Ca2+ current (ICaL) and CaV1.

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Angiostoma norvegicum n. sp. (Angiostomatidae) is described from the oesophagus, crop and the buccal mass of five species of slugs of the family Arionidae, Arion vulgaris (Moquin-Tandon), Arion ater (L.

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Studies of the distribution of ammonia oxidising archaea (AOA) and bacteria (AOB) suggest distinct ecological niches characterised by ammonia concentration and pH, arising through differences in substrate affinity and ammonia tolerance. AOA form five distinct phylogenetic clades, one of which, the 'Nitrososphaera sister cluster', has no cultivated isolate. A representative of this cluster, named 'Candidatus Nitrosocosmicus franklandus', was isolated from a pH 7.

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Aims: Liver kinase B1 (LKB1) is a protein kinase that activates the metabolic regulator AMP-activated protein kinase (AMPK) and other related kinases. Deletion of LKB1 in mice leads to cardiomyopathy and atrial fibrillation (AF). However, the specific role of the LKB1 pathway in early atrial biology remains unknown.

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Autotrophic ammonia oxidation is performed by two distinct groups of microorganisms: ammonia-oxidising archaea (AOA) and ammonia-oxidising bacteria (AOB). AOA outnumber their bacterial counterparts in many soils, at times by several orders of magnitude, but relatively little is known of their physiology due to the lack of cultivated isolates. Although a number of AOA have been cultivated from soil, Nitrososphaera viennensis was the sole terrestrial AOA in pure culture and requires pyruvate for growth in the laboratory.

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Background: Pregnancy is associated with a faster heart rate (HR), which is a risk factor for arrhythmias. However, the underlying mechanisms for this increased HR are poorly understood. Therefore, this study was performed to gain mechanistic insight into the pregnancy-induced increase in HR.

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Sex differences in responses to myocardial ischemia have been described, but whether cardiomyocyte function is influenced by sex in the setting of ischemia and reperfusion has not been elucidated. This study compared contractions and intracellular Ca(2+) in isolated ventricular myocytes exposed to ischemia and reperfusion. Cells were isolated from anesthetized 3-month-old male and female Fischer 344 rats, paced at 4 Hz (37°C), exposed to simulated ischemia (20 mins) and reperfused.

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Angiostoma margaretae n. sp. (Angiostomatidae) is described from the oesophagus of the slug Milax gagates Draparnaud collected near Caledon in the Western Cape Province of South Africa.

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Components of excitation-contraction (E-C) coupling were compared in ventricular myocytes isolated from 3-mo-old male and female rats. Ca(2+) concentrations (fura-2) and cell shortening (edge detector) were measured simultaneously (37 degrees C). Membrane potential and ionic currents were measured with microelectrodes.

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Terrestrial molluscs are diverse and are infected by many nematodes. We propose a phylogeny of slug-parasitic nematodes using 18S rRNA gene sequences from nematodes isolated from slugs collected from six countries. Eight species, representing six families of nematodes were identified and trees inferred placed them within four (I, III, IV and V) out of the five clades of Nematoda, indicating multiple origins of slug parasitism.

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We investigated whether beta-adrenoceptor stimulation exacerbates detrimental effects of ischemia and reperfusion on electrical and contractile function and on intracellular Ca(2+) homeostasis in isolated guinea pig ventricular myocytes. Myocytes were exposed to 20 min of simulated ischemia (37 degrees C) in the absence or presence of isoproterenol (10 nM, applied prior to and during ischemia) and reperfused with Tyrode's solution for 30 min. Unloaded cell shortening, Ca(2+) transients (fura-2), and cell viability were recorded at 5 min intervals in field-stimulated cells (2 Hz).

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