857 research outputs found
Bacterial Leaf Nodule Symbiosis in Flowering Plants
Bacterial leaf nodule symbiosis within angiosperms is a less known phenomenon compared to the well-documented legume root-Rhizobium symbiosis and certainly deserved much more scientific attention. Leaf nodules associated with bacteria was first recognized in Pavetta (Rubiaceae) in early twentieth century. Further survey added other members of Rubiaceae, Primulaceae, Dioscoreaceae, and Styracaceae to the short list of plants with specialized bacteria-containing structure in aerial part of plants. The actual role of the bacteria has been questioned by several researchers, mostly due to the problems associated with the identities of these unculturable bacteria. Many progresses have been achieved provided with molecular phylogenetic analysis and also genomic data of the bacteria. Recent evidence from genomic sequences showed the symbiotic bacteria may serve as a defense role in Primulaceae and Rubiaceae, and may increase stress tolerance in Dioscoreaceae. In this article, we reviewed the current knowledge of the bacterial leaf nodule symbiosis in angiosperm. Future research and applications were also discussed
Performance Assessment of ChatGPT vs Bard in Detecting Alzheimer's Dementia
Large language models (LLMs) find increasing applications in many fields.
Here, three LLM chatbots (ChatGPT-3.5, ChatGPT-4 and Bard) are assessed - in
their current form, as publicly available - for their ability to recognize
Alzheimer's Dementia (AD) and Cognitively Normal (CN) individuals using textual
input derived from spontaneous speech recordings. Zero-shot learning approach
is used at two levels of independent queries, with the second query
(chain-of-thought prompting) eliciting more detailed than the first. Each LLM
chatbot's performance is evaluated on the prediction generated in terms of
accuracy, sensitivity, specificity, precision and F1 score. LLM chatbots
generated three-class outcome ("AD", "CN", or "Unsure"). When positively
identifying AD, Bard produced highest true-positives (89% recall) and highest
F1 score (71%), but tended to misidentify CN as AD, with high confidence (low
"Unsure" rates); for positively identifying CN, GPT-4 resulted in the highest
true-negatives at 56% and highest F1 score (62%), adopting a diplomatic stance
(moderate "Unsure" rates). Overall, three LLM chatbots identify AD vs CN
surpassing chance-levels but do not currently satisfy clinical application.Comment: 22 page
Stepwise Increases in Left Ventricular Mass Index and Decreases in Left Ventricular Ejection Fraction Correspond with the Stages of Chronic Kidney Disease in Diabetes Patients
Aims. Patients with diabetic nephropathy are reported to have a high prevalence of left
ventricular structural and functional abnormalities. This study was designed to assess
the determinants of left ventricular mass index (LVMI) and left ventricular ejection
fraction (LVEF) in diabetic patients at various stages of chronic kidney disease
(CKD).
Methods. This cross-sectional study enrolled 285 diabetic patients with CKD stages 3
to 5 from our outpatient department of internal medicine. Clinical and
echocardiographic parameters were compared and analyzed.
Results. We found a significant stepwise increase in LVMI (P < 0.001), LVH (P < 0.001), and LVEF <55% (P = 0.013) and a stepwise decrease in LVEF (P = 0.038)
corresponding to advance in CKD stages.
Conclusions. Our findings suggest that increases in LVMI and decreases in LVEF coincide
with advances in CKD stages in patients with diabetes
Formation polarity dependent improved resistive switching memory characteristics using nanoscale (1.3 nm) core-shell IrOx nano-dots
Improved resistive switching memory characteristics by controlling the formation polarity in an IrOx/Al2O3/IrOx-ND/Al2O3/WOx/W structure have been investigated. High density of 1 × 1013/cm2 and small size of 1.3 nm in diameter of the IrOx nano-dots (NDs) have been observed by high-resolution transmission electron microscopy. The IrOx-NDs, Al2O3, and WOx layers are confirmed by X-ray photo-electron spectroscopy. Capacitance-voltage hysteresis characteristics show higher charge-trapping density in the IrOx-ND memory as compared to the pure Al2O3 devices. This suggests that the IrOx-ND device has more defect sites than that of the pure Al2O3 devices. Stable resistive switching characteristics under positive formation polarity on the IrOx electrode are observed, and the conducting filament is controlled by oxygen ion migration toward the Al2O3/IrOx top electrode interface. The switching mechanism is explained schematically based on our resistive switching parameters. The resistive switching random access memory (ReRAM) devices under positive formation polarity have an applicable resistance ratio of > 10 after extrapolation of 10 years data retention at 85°C and a long read endurance of 105 cycles. A large memory size of > 60 Tbit/sq in. can be realized in future for ReRAM device application. This study is not only important for improving the resistive switching memory performance but also help design other nanoscale high-density nonvolatile memory in future
Less Invasive Mitral Valve Surgery via Right Minithoracotomy
Background/PurposeCurrent trends in cardiac surgical intervention are moving toward less invasiveness, with smaller wound or sternum-sparing, less pump time or off-pump, and beating rather than arrested heart. Data on the efficacy and safety of these newer less invasive techniques, as well as their cosmetic results, are limited. This study analyzed the results of a sternum-sparing mitral valve operation.MethodsThirty patients with mitral valve diseases, including 20 who underwent mitral valve repair and 10 mitral valve replacement, were enrolled. Cardiopulmonary bypass was established via femoral cannu-lation, and blood cardioplegic arrest was induced by using a percutaneous, transthoracic cross-clamp. The main surgical wound was made over the lateral border of the right breast. Two additional small wounds were required for the transthoracic aortic clamp and the mitral retractor.ResultsThere was no operative mortality, and all patients had an uneventful recovery. Two patients underwent redo mitral surgery. Nine associated procedures were performed including tricuspid valve annulo-plasty in six patients, tricuspid valve replacement in two patients and atrial septal defect repair in one patient. The length of the main wound was between 5.8 and 7.8 cm (mean, 7.1 cm). The mean cardiopul-monary bypass time and cross-clamp time were 91.1 and 43.7 minutes, respectively. Although the length of stay was not significantly reduced compared with traditional median sternotomy, all patients had satisfactory results with good cosmesis.ConclusionSternum-sparing mitral valve surgery appears to be a safe and effective alternative to conventional mitral valve surgery; it is less invasive and provides superior cosmetic results for patients
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