Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
5,037
result(s) for
"sap"
Sort by:
Reduced Vitamin D Levels are Associated with Stroke-Associated Pneumonia in Patients with Acute Ischemic Stroke
Stroke-associated pneumonia (SAP) is a common complication in patients with acute ischemic stroke (AIS). This study explored the potential relationship between serum vitamin D levels and SAP.
This study recruited 863 consecutive AIS patients. In-hospital SAP was defined as a complication that occurred after stroke, during hospitalization, that was confirmed radiographically. Serum vitamin D levels were measured within 24 hrs of admission and the patients were divided into vitamin D sufficient (>50 nmol/L), insufficient (25-50 nmol/L), and deficient (<25 nmol/L) groups.
In this study, 102 (11.8%) patients were diagnosed with SAP. Compared to the patients without SAP, patients with SAP had significantly lower vitamin D levels (P = 0.023). The incidence of SAP was significantly higher in patients with vitamin D deficiency than in those with vitamin D insufficiency or sufficiency (21.2% vs 16.2% & 9.5%, P = 0.006). After adjusting for confounders, vitamin D deficiency and insufficiency were independently associated with SAP (OR = 3.034, 95% CI = 1.207-7.625, P = 0.018; OR = 1.921, 95% CI = 1.204-3.066, P = 0.006, respectively). In multiple-adjusted spline regression, vitamin D levels showed a linear association with the risk of SAP (P < 0.001 for linearity).
Reduced vitamin D is a potential risk factor of in-hospital SAP, which can help clinicians identify high-risk SAP patients.
Journal Article
Mechanisms of Alignment in Feeding Aphids on the Plant Stem
Aphids are observed on various plant species, with most aphids feeding downward on stems. In this study, I studied the variations in feeding postures of aphids and their mechanisms. My field observations revealed that the majority of individuals from most species fed facing downward, or more precisely, towards the roots. Exceptions included Indomegoura indica on the scapes of Hemerocallis spp., which were aligned with their head facing the sky. Next, I investigated how plant orientation affects three aphid species, Macrosiphoniella yomogifoliae, Megoura crassicauda and I. indica with different body alignments on upright immature stems. On the stems of the inverted plants, the number of Ma. yomogifoliae and Me. crassicauda in the upward position (head facing the root of the plant) was significantly greater than that in the downward position (head facing the shoot apex of the plant). If their posture is affected by gravity or by certain advantages of the headstand posture, Ma. yomogifoliae and Me. crassicauda are expected to align in a consistent direction, regardless of the orientation of the plant. This suggests that plant cues influence their posture. In contrast, the majority of I. indica were aligned with the head facing the sky on the scape, regardless of Hemerocallis's direction. This result indicates that the feeding posture of I. indica is affected by gravity and/or aphid's intrinsic factors. Therefore, this study provides a new perspective on the factors influencing aphid feeding posture preferences. This study provides the first evidence of a common feeding posture among most aphid species affected by plant cues, rather than gravity and other intrinsic factors. Also, I gained a unique insight into Indomegoura indica as they were exceptionally aligned with the head towards the sky on the stem of the upward plant and did not share the preference for orientation on the stem with the majority of aphid species.
Journal Article
Proteomic changes in the xylem sap of Brassica napus under cadmium stress and functional validation
Background
The xylem sap of vascular plants primarily transports water and mineral nutrients from the roots to the shoots and also transports heavy metals such as cadmium (Cd). Proteomic changes in xylem sap is an important mechanism for detoxifying Cd by plants. However, it is unclear how proteins in xylem sap respond to Cd. Here, we investigated the effects of Cd stress on the xylem sap proteome of
Brassica napus
using a label-free shotgun proteomic approach to elucidate plant response mechanisms to Cd toxicity.
Results
We identified and quantified 672 proteins; 67% were predicted to be secretory, and 11% (73 proteins) were unique to Cd-treated samples. Cd stress caused statistically significant and biologically relevant abundance changes in 28 xylem sap proteins. Among these proteins, the metabolic pathways that were most affected were related to cell wall modifications, stress/oxidoreductases, and lipid and protein metabolism. We functionally validated a plant defensin-like protein, BnPDFL, which belongs to the stress/oxidoreductase category, that was unique to the Cd-treated samples and played a positive role in Cd tolerance. Subcellular localization analysis revealed that BnPDFL is cell wall-localized. In vitro Cd-binding assays revealed that BnPDFL has Cd-chelating activity.
BnPDFL
heterologous overexpression significantly enhanced Cd tolerance in
E. coli
and
Arabidopsis
. Functional disruption of
Arabidopsis
plant defensin genes
AtPDF2.3
and
AtPDF2.2
, which are mainly expressed in root vascular bundles, significantly decreased Cd tolerance.
Conclusions
Several xylem sap proteins in
Brassica napus
are differentially induced in response to Cd treatment, and plant defensin plays a positive role in Cd tolerance.
Journal Article
Quantification of uncertainties in conifer sap flow measured with the thermal dissipation method
Trees play a key role in the global hydrological cycle and measurements performed with the thermal dissipation method (TDM) have been crucial in providing whole-tree water-use estimates. Yet, different data processing to calculate whole-tree water use encapsulates uncertainties that have not been systematically assessed.
We quantified uncertainties in conifer sap flux density (F
d) and stand water use caused by commonly applied methods for deriving zero-flow conditions, dampening and sensor calibration. Their contribution has been assessed using a stem segment calibration experiment and 4 yr of TDM measurements in Picea abies and Larix decidua growing in contrasting environments. Uncertainties were then projected on TDM data from different conifers across the northern hemisphere.
Commonly applied methods mostly underestimated absolute F
d. Lacking a site- and species-specific calibrations reduced our stand water-use measurements by 37% and induced uncertainty in northern hemisphere F
d. Additionally, although the interdaily variability was maintained, disregarding dampening and/or applying zero-flow conditions that ignored night-time water use reduced the correlation between environment and F
d.
The presented ensemble of calibration curves and proposed dampening correction, together with the systematic quantification of data-processing uncertainties, provide crucial steps in improving whole-tree water-use estimates across spatial and temporal scales.
Journal Article
SAP S/4HANA finance : an introduction
\"What will your financial transformation look like? This introduction to SAP S/4HANA Finance shows you next-generation finance in the new suite: financial accounting, management accounting, risk management, financial planning, and more. Consider how each process works in SAP S/4HANA, and explore the SAP Fiori apps that help you meet today's business user and reporting requirements. From previewing project planning to navigating deployment options, take your first steps toward financial transformation!\"-- Provided by publisher.
Book
Shade-induced reduction of stem nonstructural carbohydrates increases xylem vulnerability to embolism and impedes hydraulic recovery in Populus nigra
• Nonstructural carbohydrates (NSCs) have been suggested to affect xylem transport under fluctuating water availability, but conclusive evidence is still lacking. We tested the effect of shade-induced NSC depletion on xylem vulnerability to embolism and hydraulic recovery on Populus nigra saplings.
• Vulnerability was assessed in light-exposed (L) and shaded (S) plants with the hydraulic method, and in vivo with the optical method and X-ray micro-computed tomography. Plants were stressed to 80% loss of hydraulic conductance (PLC) and re-irrigated to check for possible recovery. We measured PLC, bark and wood NSC content, as well as xylem sap pH, surface tension (γ
sap) and sugar concentration, before, during and after drought.
• Shading induced depletion of stem NSC (mainly starch) reserves. All methods converged in indicating higher xylem vulnerability in S than in L plants. This difference was not explained by xylem vessel and pit anatomy or by γ
sap. Shading impeded sap acidification and sugar accumulation during drought in S plants and prevented hydraulic recovery, which was observed in L plants.
• Our results highlight the importance of stem NSCs to sustain xylem hydraulic functioning during drought and suggest that light and/or adequate stem NSC thresholds are required to trigger xylem sap chemical changes involved in embolism recovery.
Journal Article