Publications by authors named "Cousins A"

Phosphoenolpyruvate (PEP) carboxylase (PEPC) has an anaplerotic role in central plant metabolism but also initiates the carbon concentrating mechanism during C photosynthesis. The C PEPC has different binding affinities (K) for PEP (K) and HCO (K), and allosteric regulation by glucose-6-phosphate (G6-P) compared to non-photosynthetic isoforms. These differences are linked to specific changes in amino acids within PEPC.

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  • The measurement of leaf water use efficiency (WUEi) can be tricky, but analyzing leaf carbon isotope composition (δ13Cleaf) offers a promising method for large-scale screening of this trait in plants.
  • In C4 plants, the complex relationship between δ13Cleaf and WUEi is due to CO2-concentrating mechanisms, yet genetic variation in δ13Cleaf exists among different C4 species.
  • By studying two specific recombinant inbred lines of maize with different δ13Cleaf values, researchers found that faster stomatal responses to CO2 and light changes led to better WUEi, highlighting the importance of stomatal kinetics in enhancing water use efficiency.
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Consumers often cite cognitive improvements as reasons for making dietary changes or using dietary supplements, a motivation that if leveraged could greatly enhance public health. However, rarely is it considered whether standardized cognitive tests that are used in nutrition research are aligned to outcomes of interest to the consumer. This knowledge gap presents a challenge to the scientific substantiation of nutrition-based cognitive health benefits.

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  • Leaf plastids are crucial for photosynthesis and other metabolic processes in plants, and understanding their functions is linked to studying their size and volume.
  • Researchers developed three microscopy techniques to measure the in situ volumes of chloroplasts, using chlorophyll fluorescence, a CFP marker, and serial block-face scanning electron microscopy.
  • The study found that average volumes for mesophyll chloroplasts and guard cell plastids were 93 μm and 18 μm respectively, with chlorophyll fluorescence proving to be a reliable method for volume measurement, especially for labs lacking advanced equipment.
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  • The study investigates the two PEPC genes in two C4 grasses, Panicum miliaceum and Echinochloa colona, which typically possess one highly expressed PEPC gene that facilitates the carbon-concentrating mechanism in C4 photosynthesis.
  • Researchers synthesized coding sequences for the PEPC proteins from both grasses, performed point mutations, and analyzed their kinetic properties using advanced techniques.
  • Results showed that PEPCs in P. miliaceum were highly similar and had similar kinetic properties, whereas the PEPCs in E. colona had notable differences, particularly in how they responded to allosteric regulators, suggesting evolutionary variations.
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Cell wall properties play a major role in determining photosynthetic carbon uptake and water use through their impact on mesophyll conductance (CO2 diffusion from substomatal cavities into photosynthetic mesophyll cells) and leaf hydraulic conductance (water movement from xylem, through leaf tissue, to stomata). Consequently, modification of cell wall (CW) properties might help improve photosynthesis and crop water use efficiency (WUE). We tested this using 2 independent transgenic rice (Oryza sativa) lines overexpressing the rice OsAT10 gene (encoding a "BAHD" CoA acyltransferase), which alters CW hydroxycinnamic acid content (more para-coumaric acid and less ferulic acid).

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  • Measurements of oxygen isotope enrichment (Δ O) in leaf water help us understand how leaf structure and function affect water transport.
  • The study compares Δ O measurements in two mutant plant types under different light and humidity conditions to observe how cell wall properties impact water movement.
  • Findings reveal that the cell wall composition and stomatal density significantly affect Δ O, suggesting that stable isotopes can enhance models of water transport in plants.
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Background: Gastrectomy with extended (D2) lymphadenectomy is considered standard of care for gastric cancer to provide the best possible outcomes and pathologic staging. However, D2 gastrectomy is a technically demanding operation and reported to be associated with increased complications and mortality. Application of sentinel lymph node (SLN) concept in gastric cancer has the potential to reduce patient morbidity; however, SLN techniques are not established for gastrectomy, in part due to lack of practical tracers.

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Experiments were carried out to determine whether, as with other mollusks that have been studied, the snail, , can absorb, esterify and store vertebrate steroids that are present in the water. We also carried out experiments to determine whether neural tissues of the snail could be immunohistochemically stained with an antibody to human aromatase (a key enzyme that catalyzes the conversion of testosterone [T] to 17β-estradiol [E]); and, if so, to determine the significance of such staining. Previous studies on other mollusks have reported such staining and have proposed this as decisive evidence that mollusks have the same steroid synthesis pathway as vertebrates.

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Background: Sentinel lymph node biopsy (SLNB) is a staging procedure dependent on accurate mapping of draining lymphatics via tracers. Robot-assisted SLNB enables access to multiple neck levels with a single incision and intraoperative fluorescence guidance to the SLN.

Methods: Lymphatic mapping in swine was done using a magnetic tracer and fluorescent dye, injected into the tongue.

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Mesophyll CO conductance (g ) in C species responds to short-term (minutes) changes in environment potentially due to changes in leaf anatomical and biochemical properties and measurement artefacts. Compared with C species, there is less information on g responses to short-term changes in environmental conditions such as partial pressure of CO (pCO ) across diverse C species and the potential determinants of these responses. Using 16 C grasses we investigated the response of g to short-term changes in pCO and its relationship with leaf anatomy and biochemistry.

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In recent years, researchers have attempted to improve photosynthesis by introducing components from cyanobacterial and algal CO2-concentrating mechanisms (CCMs) into terrestrial C3 plants. For these attempts to succeed, we need to understand the CCM components in more detail, especially carbonic anhydrase (CA) and bicarbonate (HCO3−) transporters. Heterologous complementation systems capable of detecting carbonic anhydrase activity (i.

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In C4 plants, the pyruvate (Pyr), phosphate dikinase regulatory protein (PDRP) regulates the activity of the C4 pathway enzyme Pyr, phosphate dikinase (PPDK) in a light-/dark-dependent manner. The importance of this regulatory action to C4 pathway function and overall C4 photosynthesis is unknown. To resolve this question, we assessed in vivo PPDK phospho-regulation and whole leaf photophysiology in a CRISPR-Cas9 PDRP knockout (KO) mutant of the NADP-ME C4 grass green millet (Setaria viridis).

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Environmental variability poses a major challenge to any field study. Researchers attempt to mitigate this challenge through replication. Thus, the ability to detect experimental signals is determined by the degree of replication and the amount of environmental variation, noise, within the experimental system.

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Drought resiliency strategies combine developmental, physiological, cellular, and molecular mechanisms. Here, we compare drought responses in two resilient spring wheat ( genotypes: a well-studied drought-resilient Drysdale and a resilient genotype from the US Pacific North-West Hollis. While both genotypes utilize higher water use efficiency through the reduction of stomatal conductance, other mechanisms differ.

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Sentinel lymph node biopsy in cancers of the head and neck offers demonstrated clinical and diagnostic value, but adoption is limited by concerns about the detrimental consequence to survival of false negative results in a highly curable setting. The aim of this study was to demonstrate potential to overcome this via application of a novel mannose-labeled magnetic iron oxide tracer. In a large animal model, preoperative imaging and intraoperative magnetometer detection were used to identify magnetic lymph nodes.

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Unlabelled: Caregivers of individuals with ASD can experience various practical, psychological, and social demands and need effective ways of coping to ameliorate the negative effects of caregiving. Numerous coping strategies are available, but the literature shows that caregivers can still struggle to cope, suggesting that interventions to support coping efforts could be beneficial. The MRC framework advocates the systematic development and evaluation of interventions, and this study was conducted to inform the future development of a self-help Positive Reappraisal Coping Intervention (PRCI) for these caregivers.

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Article Synopsis
  • Carbonic anhydrase (CA) plays a crucial role in C4 photosynthesis by converting dissolved CO into bicarbonate, which is then used in the carbon-concentrating mechanism (CCM).
  • A study found that maize plants lacking two main types of CA (ca1ca2 double mutant) had significantly reduced CA activity but showed little difference in growth under normal CO levels, suggesting other factors might compensate.
  • Further experiments removing a third CA (CA8) from these plants led to almost complete loss of CA activity, resulting in poor photosynthetic performance and dependence on higher CO levels, indicating insufficient CA activity for effective C4 CCM function.
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This study investigated the application of a recurrent neural network for optimising pharmacological treatment for depression. A clinical dataset of 458 participants from specialist and community psychiatric services in Australia, New Zealand and Japan were extracted from an existing custom-built, web-based tool called . This data, which included baseline and self-completed reviews, was used to train and refine a novel algorithm which was a fully connected network feature extractor and long short-term memory algorithm was firstly trained in isolation and then integrated and annealed using slow learning rates due to the low dimensionality of the data.

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Previous toxicokinetic studies have shown that mussels ( spp.) can readily absorb the three main mammalian sex steroids, estradiol (E), testosterone (T) and progesterone (P) from water. They also have a strong ability to store E and the 5α-reduced metabolites of T and P in the form of fatty acid esters.

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The CO2-concentrating mechanism (CCM) in C4 plants is initiated by the uptake of bicarbonate (HCO3-) via phosphoenolpyruvate carboxylase (PEPC). Generation of HCO3- for PEPC is determined by the interaction between mesophyll CO2 conductance and the hydration of CO2 to HCO3- by carbonic anhydrase (CA). Genetic reduction of CA was previously shown not to limit C4 photosynthesis under ambient atmospheric partial pressures of CO2 (pCO2).

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With increased demand on freshwater resources for agriculture, it is imperative that more water-use efficient crops are developed. Leaf stable carbon isotope composition, δ13C, is a proxy for transpiration efficiency and a possible tool for breeders, but the underlying mechanisms effecting δ13C in C4 plants are not known. It has been suggested that differences in specific leaf area (SLA), which potentially reflects variation in internal CO2 diffusion, can impact leaf δ13C.

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B-cell acute lymphoblastic leukemia (B-ALL) occurs most commonly in children, whereas chronic myeloid leukemia is more frequent in adults. The myeloid bias of hematopoiesis in elderly individuals has been considered causative, but the age of the bone marrow microenvironment (BMM) may be contributory. Using various murine models of B-ALL in young vs old mice, we recapitulated B-ALL preponderance in children vs adults.

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The engineering of C photosynthetic activity into the C plant rice has the potential to nearly double rice yields. To engineer a two-cell photosynthetic system in rice, the rice bundle sheath (BS) must be rewired to enhance photosynthetic capacity. Here, we show that BS chloroplast biogenesis is enhanced when the transcriptional activator, Oryza sativa Cytokinin GATA transcription factor 1 (OsCGA1), is driven by a vascular specific promoter.

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