Enhancing strength and electrical conductivity of pure aluminum by microalloying with telluride

The effects of Te addition on the microstructure, strength and electrical conductivity of pure aluminum were investigated, for improving the strength and electrical conductivity of resulting alloys. It was found that the tensile strength and electrical conductivity of the studied alloys increased by 25.8% and 2.8%, respectively, compared with those for pure aluminum (58 MPa and 62.06% IACS), respectively, by adding 0.1 wt% Te. Several mechanisms may account for the observed improvement of the alloys’ strength and electrical conductivity. First, Te addition can refine the grain size of pure aluminum by introducing more nucleation sites and suppressing grain growth through boundary precipitation. Second, the precipitation morphology changes from fine-needle or sheet-like to ellipsoidal shapes, likely improving the alloys’ tensile properties. Finally, Te can purify the melts by forming Al-Te-Fe-Si intermetallics at the grain boundaries, likely reducing the lattice distortion and increasing the electrical conductivity

Research and Experiment on Soybean Plant Identification Based on Laser Ranging Sensor

When endeavoring to study the complex growth conditions of soybean plants under natural conditions, a problem arises due to the similar appearances of both soybean plants and weeds. To address this issue, a soybean plant recognition model based on a laser ranging sensor is proposed. To demonstrate the applicability of the soybean plant recognition model, experiments are conducted using ultrasonic sensors and laser ranging sensors to analyze the diameter, height, and spacing conditions in the model. A test environment is built, and during the pre-test, the laser range sensor detects objects with diameters of 3 mm and 5 mm with two and three measurement points, respectively, at a speed of 0.2 m/s. At a speed of 0.3 m/s, there is one measurement point for objects with 3 mm diameter and two measurement points for objects with 5 mm diameter. At 0.4 m/s, there are also one and two measurement points for objects with diameters of 3 mm and 5 mm, respectively. These results demonstrate that the laser range sensor can more accurately recognize the diameter conditions of soybean plants and weeds and can distinguish between the diameters of soybean plants and weeds. Subsequently, the recognition rate of the model is evaluated by observing whether the weeding mechanism can synchronize seedling avoidance after the soybean plant passes through the sensor. The recognition rates of the optimized model at speeds of 0.2 m/s, 0.3 m/s, and 0.4 m/s are 100%, 98.75%, and 93.75%, respectively. Upon comprehensive analysis, the soybean plant recognition model is determined to achieve a recognition rate of 98.75% at a speed of 0.3 m/s, which is considered a moderate speed, and demonstrates more stable recognition of plant diameters. The test further verifies the reliability and effectiveness of the method for distinguishing between soybean plants and weeds. The research results can serve as a reference for recognizing soybean plants based on the use of laser ranging sensors

Distributed Face Recognition in Wireless Sensor Networks

As one of the most successful applications of image analysis and understanding, face recognition has recently received significant attention, especially during the past few years. In order to construct an autonomous and robust biometric security system, this paper explores the application of face recognition technique in wireless sensor networks. Given the limited technological resources of sensor nodes, new challenges remain to be met. In this work, a facial component-based recognition mechanism is firstly applied to ensure the recognition accuracy. Secondly, in order to address the problem of resource constraints, a distributed scheme based on K-d trees is deployed for both the face image transmission and retrieval. According to the simulation results, the proposed method is capable of achieving considerable energy efficiency, while assuring the recognition accuracy

Maintenance Therapy with Immunomodulatory Drugs after Autologous Stem Cell Transplantation in Patients with Multiple Myeloma: A Meta-Analysis of Randomized Controlled Trials

<div><p>Background</p><p>Although high-dose therapy (HDT) with autologous stem cell transplantation (ASCT) has been confirmed to result in longer remission time than conventional chemotherapy, multiple myeloma (MM) remains incurable. Post-ASCT maintenance is considered as a strategy for obtaining durable remissions and preventing tumor progression. Randomized controlled trials (RCTs) studying maintenance therapy with immunomodulatory drugs (IMiDs) after ASCT have shown some valuable survival improvements. This meta-analysis of RCTs therefore assesses the effect of post-ASCT IMiDs maintenance on MM patients.</p> <p>Methods</p><p>We performed a meta-analysis to evaluate the impact of IMiDs (thalidomide or lenalidomide) as post-ASCT maintenance therapy on the survival of newly diagnosed MM patients. The outcomes for this meta-analysis were progression-free survival (PFS) and overall survival (OS).</p> <p>Results</p><p>Eight RCTs enrolling 3514 patients were included for analysis. An obvious improvement in Os (hazard ratio [HR] 0.75) and a significant PFS advantage (HR 0.58) with post-ASCT IMiDs maintenance was revealed. Thalidomide maintenance after ASCT can result in significant benefit in Os (HR 0.72), particularly combined with corticosteroids (HR 0.66).</p> <p>Conclusions</p><p>MM patients after ASCT have a significant overall survival benefit with IMiDs maintenance. IMiDs maintenance was justified for MM patients who received HDT with ASCT.</p> </div

Meta-analysis of overall survival (OS) with IMiDs maintenance after ASCT.

<p>(<b>A</b>) OS with post-ASCT IMiDs maintenance. (<b>B</b>) OS with post-ASCT IMiDs maintenance, subgroup analysis according to thalidomide (Group 1) or lenalidomide (Group 2) as maintenance therapy. (<b>C</b>) OS with thalidomide maintenance, subgroup analysis according to non-IMiDs maintenance (Group 1) or no maintenance (Group 2) in the control arm. (<b>D</b>) OS with thalidomide maintenance, subgroup analysis according to corticosteroids combined with thalidomide (Group 1) or thalidomide alone (Group 2) as maintenance in the experimental arm. Abbreviations: IMiDs, immunomodulatory drugs.</p

Flow diagram of study selection in the meta-analysis.

<p>Flow diagram of study selection in the meta-analysis.</p