14 research outputs found
Interactions between subjective memory complaint and objective cognitive deficit on memory performances
Background
Subjective memory complaint (SMCs) is a common trait amongst older population. The subjective cognition about their memory could depend on objective cognition. The aim of the current study was to examine the interaction between subjective memory cognition (i.e., SMC) and objective cognition on cognitive functions in participants from older generation.
Methods
A total of 219 patients, 181 normal control (NC) patients and 38 patients with mild cognitive impairment (MCI), were examined through standardized and comprehensive clinical evaluation and neuropsychological assessment. The Subjective Memory Complaints Questionnaire was used to assess SMCs along with five cognitive tasks were used to evaluate cognitive decline over following areas: verbal memory, visuospatial memory, attention, fluency, and language.
Results
The results of 2 × 2 two-way analysis of variance (ANOVA) showed that there were significant interactions between SMCs and cognitive status (NC, MCI) on memory performances. NC with SMCs showed significantly lower performance in verbal memory and visuospatial memory compared to NCs without SMCs. Conversely, no effect was observed in the MCI group.
Conclusion
There are interactions between subjective cognition (i.e., SMC) and objective cognition (i.e., cognitive status) on memory performances in older adults. The roles of SMCs on memory performances should be interpreted with older adults objective cognitive status.This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. NRF-2017R1D1A1A02018479). This funding source had no role in the design of this study and will not have any role during its execution,
analyses, interpretation of the data, or decision to submit result
Effects of seasonal variations on sediment-plume streaks from dredging operations
When mixtures of aggregates and water dredged from the seabed are discharged at the surface into the adjacent water from a barge, coarse sediments sink immediately and fine sediments are suspended forming a plume. Recently, elongated plumes of fine sediment were observed by satellites near a dredging location on the continental shelf. Such plume streaks were longer in certain conditions with seasonality than expected or reported previously. Therefore, the present work studied the appearance of sediment plume with field measurements and numerical simulations and explains the seasonally varying restoring force and thicknesses of the surface mixed layer resulting from the vertical density distribution near the surface, along with mixing by hydrodynamic process. The resulting mixtures, after vertical restoring and mixing with the surroundings, determine the horizontal transport of suspended sediments. A numerical model successfully reproduced and explained the results from field measurements and satellite images along with the seasonal variations
Ontogeny-dependent effects of elevated CO2 and watering frequency on interaction between Aristolochia contorta and its herbivores
Effects of environmental change on plants can differ due to sequential changes in their life-history strategies (i.e., ontogenetic variations). The fitness of herbivorous insects by physiological changes of the host plant could be affected depending on their diet breadth. However, little is known regarding the combinational effects of plant ontogeny and climate change on plant-herbivore interactions. This study examined the plant ontogeny-dependent effects of climate change on the interaction between a host plant (Aristolochia contorta), its specialist herbivore (Sericinus montela), and a generalist herbivore (Spodoptera exigua). Plants were grown under a factorial design of two distinct CO2 concentrations (ambient, 400 ppm; elevated, 560 ppm) and two watering frequencies (control, once a week; increased, twice a week). Plant ontogeny ameliorated the effects of climate change by altering its defensive traits, where nutrient-related factors were cumulatively affected by climate change. Herbivore performance was assessed at three different plant ontogenetic stages (1st-year juvenile, 1st-year senescence, and 2nd-year juvenile). Elevated CO2 levels reduced the growth and survival of the specialist herbivore, whereas increased watering frequency partially alleviated this reduced performance. Generalist herbivore performance slightly increased under elevated CO2 levels with progressing ontogenetic stages. The effects of climate change, both elevated CO2 and increased watering frequency were weaker in 2nd-year juveniles than in 1st-year juveniles. Elevated CO2 levels detrimentally affected the nutritional quality of A. contorta leaves. The effects of climate change on both specialist and generalist herbivore performance differed as plant ontogenetic stage proceeded. Increased growth rates and survival of the generalist herbivore at the latter ontogenetic stage might negatively affect the population dynamics of a specialist herbivore. This study suggests that biases are possible when the plant herbivore interaction under a changing environment is predicted from a singular plant ontogenetic stage.N
Effects of Irradiation on Brain Tumors Using MR-Based Electrical Conductivity Imaging
Ionizing radiation delivers sufficient energy inside the human body to create ions, which kills cancerous tissues either by damaging the DNA directly or by creating charged particles that can damage the DNA. Recent magnetic resonance (MR)-based conductivity imaging shows higher sensitivity than other MR techniques for evaluating the responses of normal tissues immediately after irradiation. However, it is still necessary to verify the responses of cancer tissues to irradiation by conductivity imaging for it to become a reliable tool in evaluating therapeutic effects in clinical practice. In this study, we applied MR-based conductivity imaging to mouse brain tumors to evaluate the responses in irradiated and non-irradiated tissues during the peri-irradiation period. Absolute conductivities of brain tissues were measured to quantify the irradiation effects, and the percentage changes were determined to estimate the degree of response. The conductivity of brain tissues with irradiation was higher than that without irradiation for all tissue types. The percentage changes of tumor tissues with irradiation were clearly different than those without irradiation. The measured conductivity and percentage changes between tumor rims and cores to irradiation were clearly distinguished. The contrast of the conductivity images following irradiation may reflect the response to the changes in cellularity and the amounts of electrolytes in tumor tissues
Comparaison des echantillonnages aleatoires et stratifies pour la mesure de la biomasse sur pied d'un parcours herbeux a Oryza longistaminata des plaines d'inondation du Niger
Etude comparative de divers protocoles de mesure de la biomasse aerienne du tapis herbace pour inventorier le potentiel fourrager des parcours a Oryza longistaminata des plaines d'inondation du Niger proche de Moura et de ses abords saheliens a l'aide d'une comparaison de deux modes d'echantillonage aleatoire et stratifie
Cold and hypoxia induce aquatic leaf development in <i>R</i>. <i>trichophyllus</i>.
<p>(A) Heterophylly induced by cold and hypoxia. 1 week-old seedlings after germination on the MS media were transferred to cold chamber (4°C) for 1 month or hypoxia chamber (1% O<sub>2</sub>) for 2 weeks. The column Room Temp is a control at 22°C with 20% O<sub>2</sub>. (B and C) Gene expression analyses of <i>KAN</i> genes (B), and <i>HD-ZIPIII</i> genes (C) in the leaves after cold for 1 month and hypoxia for 2 weeks treated. *<i>P</i> < 0.05; **<i>P</i> < 0.01 (unpaired Student’s <i>t</i>-test).</p
Transcriptome analysis of aquatic vs terrestrial plants of <i>R</i>. <i>trichophyllus</i>.
<p>(A) Venn diagram of differentially expressed transcripts with two fold changes for three independent experiments. Numbers are up- or down-regulated genes in aquatic plants compared to terrestrial plants. (B) Diagram for large ontology categories showing up-regulation in aquatic plants by BinGo software. Number of genes is represented by relative size of circles that belong to each gene ontology term. (C) Relative expression of genes affiliated to four developmental GO terms for terrestrial vs aquatic plants of <i>R</i>. <i>trichophyllus</i>. Up-regulated genes are painted with red and down-regulated genes are painted with blue. (D) Diagram of up-regulated genes in aquatic plants for ontology categories of plant hormone response genes by the BinGo software. The seedlings, 1 week-old after germination, were transferred to terrestrial or aquatic condition for 10 days. Upper parts of seedlings including leaves and shoot apexes were harvested for RNA sequencing.</p
Heterophyllic leaf developments depending on environments are shown in <i>R</i>. <i>trichophyllus</i> but not in sister species, <i>R</i>. <i>sceleratus</i>.
<p>Seedling morphologies and microscopic images of <i>R</i>. <i>trichophyllus</i> (A) and <i>R</i>. <i>sceleratus</i> (B) grown under aerial vs aquatic environments. Seeds of <i>R</i>. <i>trichophyllus</i> or <i>R</i>. <i>sceleratus</i> were germinated on solid MS media for 1 week, then transferred to aerial or aquatic environments. The true leaves produced at 7 days after transference were used for analysis. (<i>a-d</i>) terrestrial and (<i>e-h</i>) aquatic/submerged plants, (<i>b</i>, <i>c</i>) cell shapes of terrestrial leaves and (<i>f</i>, <i>g</i>) those of aquatic/submerged leaves, (<i>d</i>) vasculature of terrestrial and (<i>h</i>) that of aquatic leaves. (<i>i-k</i>) Statistical analyses of leaf indices (<i>i</i>), stomatal densities (<i>j</i>), and number of vessel elements (<i>k</i>) in terrestrial and aquatic/submerged leaves. Data are collected from 24 individual samples and presented as means ± SD from three biological replicates. Black arrowheads denote stomata and white arrowheads denote individual vessel element.</p
Effects of ethylene and ABA signalings on the promoter activation of leaf polarity genes and genes critical for stomata and vascular developments.
<p>(A and B) Luminescence analysis of <i>proRtKANa</i>::<i>LUC</i> when added with ACC, an ethylene precursor, or ABA in protoplast solution (A), control; without chemical treatment, and when cotransfected with <i>CFP-RtEIN3</i> in protoplasts (B), control; cotransfected with <i>CFP</i> construct. (C) Effects of <i>CFP-RtEIN3</i> transfection on the relative expressions of endogenous <i>KAN</i> genes in protoplasts, control; transfected with <i>CFP</i> construct. (D and E) Luminescence analysis of <i>proHD-ZIPIIIa</i>::<i>LUC</i> when added with ACC or ABA in protoplast solution (D), control; without chemical treatment, and when cotransfected with <i>CFP-RtABI3</i> in protoplasts (E), control; cotransfected with CFP construct. (F) Effects of <i>CFP-RtABI3</i> transfection on the relative expressions of endogenous <i>HD-ZIPIII</i> genes in protoplasts, control; transfected with <i>CFP</i> construct. (G) Relative transcript levels of <i>RtSTO</i> and <i>RtVDN7</i>, encoding critical regulators of stomata and vascular developments, when transfected with <i>Rt-EIN3</i>, <i>Rt-ABI3</i>, and <i>RtHD-ZIPIIIa</i> fused with <i>CFP</i> coding sequence. Control; transfected with <i>CFP</i> construct. (H) Comparison of transcript levels of <i>RtSTO</i> and <i>RtVND7</i> between terrestrial and aquatic leaves of <i>R</i>. <i>trichophyllus</i>. *<i>P</i> < 0.05; **<i>P</i> < 0.01; ***<i>P</i> < 0.001 (unpaired Student’s <i>t</i>-test).</p