VMA: Divide-and-Conquer Vectorized Map Annotation System for Large-Scale Driving Scene

High-definition (HD) map serves as the essential infrastructure of autonomous driving. In this work, we build up a systematic vectorized map annotation framework (termed VMA) for efficiently generating HD map of large-scale driving scene. We design a divide-and-conquer annotation scheme to solve the spatial extensibility problem of HD map generation, and abstract map elements with a variety of geometric patterns as unified point sequence representation, which can be extended to most map elements in the driving scene. VMA is highly efficient and extensible, requiring negligible human effort, and flexible in terms of spatial scale and element type. We quantitatively and qualitatively validate the annotation performance on real-world urban and highway scenes, as well as NYC Planimetric Database. VMA can significantly improve map generation efficiency and require little human effort. On average VMA takes 160min for annotating a scene with a range of hundreds of meters, and reduces 52.3% of the human cost, showing great application value

Impact of early enteral nutrition on short term prognosis after acute stroke

We hypothesized that early enteral nutritional support would improve the short term prognosis of acute stroke patients with dysphagia, demonstrated by lower malnutrition rates, lower complication rates, and lower National Institutes of Health Stroke Scale (NIHSS) scores at 90 days post stroke. Nutrition support is an essential element in the care of stroke patients and many studies have investigated the effect of specific nutritional elements on stroke patients. However, few studies have looked at the impact of complete enteral nutrition on Chinese patients with acute stroke. To investigate this, we conducted a randomized controlled trial of 146 patients with acute stroke and dysphagia, among whom 75 were supported with nasogastric nutrition and 71 received family managed nutrition after randomization. Nutritional status, nosocomial infection and mortality rates were recorded on day 21 of hospitalization. Neurological deficits were evaluated by the NIHSS activities of daily living Barthel index (ADLBI) and the modified Rankin scale (mRS) and compared between the two groups. We found that the nasogastric nutrition group had a better nutritional status and reduced nosocomial infection and mortality rates after 21 days compared with patients in the family managed nutrition group. In addition, the nasogastric nutrition group showed a lower score on the NIHSS than the control group. However, the differences in the scores of the ADLBI and the 90 day mRS between the groups were not significant. Taken together, the present study shows that early enteral nutrition support improves the short term prognosis of acute stroke patients with dysphagia

Orthostatic hypotension predicts cognitive impairment in the elderly : findings from a cohort study

Background: Orthostatic hypotension (OH) is a known risk factor for cerebral ischemia, but its correlation with cognitive impairment (CI) is not well established. Objective: The aim of this study is to explore the relationship between OH and CI in the elderly. Methods: The study group consisted of 44 OH patients who presented with drowsiness, vertigo, and fatigue between January 2009 and December 2011 (OH group). Eighty-eight healthy elderly were paired with those in the OH group in a 1:2 based on their education levels (NOH group). Baseline sociodemographic information and cognition-related measures were collected for both groups. Cognitive function was assessed 4 years later using MMSE. Results: The overall incidence of CI was 14.0% among the 114 subjects who completed the follow-up assessment. There was a significant difference in the incidence of CI between the OH group (23.7%) and the NOH group (9.2%) (χ2 = 4.399, P = 0.036). After excluding the influence of age (OR = 1.199, 95% CI: 1.072–1.340, P = 0.001) and education years (OR = 0.568, 95% CI: 0.371–0.869, P = 0.009), OH (OR = 4.047, 95% CI: 1.144–14.313, P = 0.030) became an independent risk factor for CI. Conclusion: OH can lead to CI. We suggest that future studies, with a larger sample size, use OH exposure time instead of OH exposure population to verify the conclusion of this study

A single-cell atlas of Drosophila trachea reveals glycosylation-mediated Notch signaling in cell fate specification

Abstract The Drosophila tracheal system is a favorable model for investigating the program of tubular morphogenesis. This system is established in the embryo by post-mitotic cells, but also undergoes remodeling by adult stem cells. Here, we provide a comprehensive cell atlas of Drosophila trachea using the single-cell RNA-sequencing (scRNA-seq) technique. The atlas documents transcriptional profiles of tracheoblasts within the Drosophila airway, delineating 9 major subtypes. Further evidence gained from in silico as well as genetic investigations highlight a set of transcription factors characterized by their capacity to switch cell fate. Notably, the transcription factors Pebbled, Blistered, Knirps, Spalt and Cut are influenced by Notch signaling and determine tracheal cell identity. Moreover, Notch signaling orchestrates transcriptional activities essential for tracheoblast differentiation and responds to protein glycosylation that is induced by high sugar diet. Therefore, our study yields a single-cell transcriptomic atlas of tracheal development and regeneration, and suggests a glycosylation-responsive Notch signaling in cell fate determination

Metallic aluminum suboxides with ultra-high electrical conductivity at high pressure

Aluminum, as the most abundant metallic elemental content in the Earth’s crust, usually exists in the form of alumina (Al2O3). However, the oxidation state of aluminum and the crystal structures of aluminum oxides in the pressure range of planetary interiors is not well established. Here, we predicted two aluminum suboxides (Al2O, AlO) and two superoxides (Al4O7, AlO3) with uncommon stoichiometries at high pressures using first-principles calculations and crystal structure prediction methods. We find that the P4/nmm Al2O becomes stable above ~765 GPa, and may survive in the deep mantles or cores of giant planets such as Neptune. Interestingly, the Al2O and AlO are metallic and have electride features, in which some electrons are localized in the interstitials between atoms. We find that Al2O has an electrical conductivity one order of magnitude higher than that of iron under the same pressure-temperature conditions, which may influence the total conductivity of giant planets. Our findings enrich the high-pressure phase diagram of aluminum oxides and improve our understanding of the interior structure of giant planets