48 research outputs found
Modeling Hidden Nodes Collisions in Wireless Sensor Networks: Analysis Approach
This paper studied both types of collisions. In this paper, we show that advocated solutions for coping with hidden node collisions are unsuitable for sensor networks. We model both types of collisions and derive closed-form formula giving the probability of hidden and visible node collisions. To reduce these collisions, we propose two solutions. The first one based on tuning the carrier sense threshold saves a substantial amount of collisions by reducing the number of hidden nodes. The second one based on adjusting the contention window size is complementary to the first one. It reduces the probability of overlapping transmissions, which reduces both collisions due to hidden and visible nodes. We validate and evaluate the performance of these solutions through simulations
Automatic Recognition of Laryngoscopic Images Using a Deep-Learning Technique
Objectives/Hypothesis: To develop a deep-learning–based computer-aided diagnosis system for distinguishing laryngeal neoplasms (benign, precancerous lesions, and cancer) and improve the clinician-based accuracy of diagnostic assessments of laryngoscopy findings. Study Design: Retrospective study. Methods: A total of 24,667 laryngoscopy images (normal, vocal nodule, polyps, leukoplakia and malignancy) were collected to develop and test a convolutional neural network (CNN)-based classifier. A comparison between the proposed CNN-based classifier and the clinical visual assessments (CVAs) by 12 otolaryngologists was conducted. Results: In the independent testing dataset, an overall accuracy of 96.24% was achieved; for leukoplakia, benign, malignancy, normal, and vocal nodule, the sensitivity and specificity were 92.8% vs. 98.9%, 97% vs. 99.7%, 89% vs. 99.3%, 99.0% vs. 99.4%, and 97.2% vs. 99.1%, respectively. Furthermore, when compared with CVAs on the randomly selected test dataset, the CNN-based classifier outperformed physicians for most laryngeal conditions, with striking improvements in the ability to distinguish nodules (98% vs. 45%, P <.001), polyps (91% vs. 86%, P <.001), leukoplakia (91% vs. 65%, P <.001), and malignancy (90% vs. 54%, P <.001). Conclusions: The CNN-based classifier can provide a valuable reference for the diagnosis of laryngeal neoplasms during laryngoscopy, especially for distinguishing benign, precancerous, and cancer lesions. Level of Evidence: NA Laryngoscope, 130:E686–E693, 2020
Spectrum of somatic mutations detected by targeted next-generation sequencing and their prognostic significance in adult patients with acute lymphoblastic leukemia
Parent Involvement and Mathematics Achievement: Contrast Across Racial and Ethnic Groups
Alternative mechanism for duodenal ulcer
The association between duodenal ulcer and ambient temperatures or seasonal transitions suggests that energy metabolism is implicated in the disorder. Since antibiotic treatment is not universally effective for duodenal ulcer recovery, the theory of Helicobacter pylori colonization cannot account for all the cases. Here we hypothesize that the shunt of Krebs cycle and other pathways of energy metabolism generate oxalate, while the insoluble and rigid calcium oxalate may cause duodenal ulcer
Combining weak acids and fasting could be a viable strategy against infections by Ebola-like viruses
Ebola-like viruses could depend on chloride or HCl to deliver lethal assault on human cells, causing hemorrhaging, bleeding, diarrhea, etc. It may harbor stressful peptides which can be generated in vivo after infections. Fasting with boiled rice water or with orange juice for a few days can halt virion production. However, infection-triggered cell lysis can produce nutrients for viral proliferation. The adoption of highly diluted weak organic acids such as acetic acid or lactic acid for smearing skin or foot bathing can neutralize chloride or HCl after absorption, and raise cellular pH to minimize cell lysis. Integration of fasting/fruit juice intake and highly diluted weak acids might reduce mortality rates of Ebola-like virus infections. The intake of NaCl should be minimized as it can give rise to chloride or HCl in cell microenvironment. Many food ingredients such as vinegar and sauce contain salt. Clinical trials must be conducted before the regimen is available for use
Revelations from shared sequence features in the encoded proteins of examined plant insect-resistance genes
Plant insect-resistance genes play pivotal roles in the fight against agricultural pests. Yet, their common sequence features have not been extensively explored. Here we show that valine plus glycine is overrepresented in the encoded proteins of these genes. Additionally, lower valine plus glycine content in some proteins is complemented by higher basic amino acid content. Valine and glycine possess long carbonyl bond length and thus weaker carbonyl bond, and consequently boast potent secondary chemical bonding of carbonyl oxygen to divalent cations. The aforementioned amino acids collectively build up calcium and oxalate, giving rise to insoluble and stiff calcium oxalate and other insoluble calcium salts which are stressful to cells and cause cell senescence. The chemical and biochemical perspective can complement our current understanding on the mode of action of plant insect-resistance genes. This insight may be important in the development of novel insecticides
Numerical Simulation of Aerodynamic Performance of Off-grid Small Vertical Axis Wind Turbine
In this paper, a 2D off-grid small compact model of vertical axis wind turbine was established. The sliding grid technology, the RNG turbulence model and the Coupld algorithm was applied to simulate the unsteady value of the model's aerodynamic performance. Through the analysis on the flow field at difference moments, the rules about velocity fields, vortices distributions and the wind turbine's total torque were obtained. The results show that: the speed around wind turbine blades have obvious gradient, and the velocity distribution at different times show large differences in the computional domain. In the rotating domain vorticity is large. With away from the rotation domain, vorticity reduced quickly. In the process of rotating for vertical axis wind turbine, the wind turbine's total torque showed alternating positive and negative changes
Numerical Simulation of Aerodynamic Performance of Off-grid Small Vertical Axis Wind Turbine
In this paper, a 2D off-grid small compact model of vertical axis wind turbine was established. The sliding grid technology, the RNG turbulence model and the Coupld algorithm was applied to simulate the unsteady value of the model's aerodynamic performance. Through the analysis on the flow field at difference moments, the rules about velocity fields, vortices distributions and the wind turbine's total torque were obtained. The results show that: the speed around wind turbine blades have obvious gradient, and the velocity distribution at different times show large differences in the computional domain. In the rotating domain vorticity is large. With away from the rotation domain, vorticity reduced quickly. In the process of rotating for vertical axis wind turbine, the wind turbine's total torque showed alternating positive and negative changes
Simultaneous fasting may contain SARS-CoV-2 infection
Fasting can halt viral reproduction and relieve symptoms. Simultaneous fasting with moderate intake of boiled rice water or fruit juice for 2 to 3 days may achieve positive effect. If a person has 30 contacts daily, and 6 of which are viral carriers, simultaneous fasting can reduce viral loads in all the 6 carriers and thus lower infection rate by perhaps more than 90%. Individuals not suitable for fasting should be excluded from pilot test and large experiments. Multiple episodes of fasting with proper intervals can be conducted to beat pandemic or control viral infection at its infancy