Real-time data of high-voltage infrastructures collected by wireless sensors are the foundation of many smart grid applications. Energy harvesting can be an effective solution for autonomous, ...self-powered wireless sensors. In this paper, a coil with a novel helical core is proposed and optimized to scavenge the magnetic field energy efficiently near equipment carrying large currents. Due to the special design of the helical core, the path of the magnetic flux inside the core can be significantly increased, which leads to a reduction of the demagnetizing field. Therefore, the proposed core can generate a much higher flux density (hence more power) compared with conventional designs. The selection of the core material is studied and itis found that high permeability ferrite is the most suitable material. Experimental results show that the proposed helical coil with only 400 turns of wire can have a power density of 2.1 μW/cm 3 when placed in a magnetic flux density of 7 μTrm s. This value is bigger than any of the existing designs if placed in the same magnetic field. If more wires can be wound on the core, an even higher power density could be obtained. Therefore, the proposed design is a very efficient method for scavenging the magnetic field energy for a wide range of smart grid applications.
Glioblastoma is a common malignant primary intracranial tumor characterized by rapid invasive growth and a high recurrence rate after surgery. MicroRNAs (miRNAs) are involved in cell proliferation, ...differentiation, and apoptosis, and abnormal miRNA expression is associated with the occurrence and progression of various tumors, including glioblastomas. The aim of this study was to determine the levels of miR-148a and integrin subunit alpha 9 (ITGA9) in glioblastoma tissues and cells and their involvement in cancer cell proliferation and migration. Glioblastoma tissues from 19 patients and two glioblastoma cell lines (U87 and LN229) were used in this study. The effects of miR-148a on cell viability, proliferation, colony formation, migration, and invasion were assessed. Glioblastomas were xenografted in nude mice to examine the effects of miR-148a overexpression on tumor growth in vivo. Levels of ITGA9 mRNA and protein in glioblastoma tissues were detected by quantitative reverse transcription PCR and western blot analysis, respectively. The interaction between miR-148a and ITGA9 was determined by a dual-luciferase reporter gene assay. We found that the overexpression of miR-148a decreases the proliferation, clustering, migration, and invasiveness of U87 and LN229 cells and inhibits the tumorigenicity of xenografted glioblastomas. We confirmed that ITGA9 is the target of miR-148a. Restoration of ITGA9 expression reversed the decreased viability, migration, and invasiveness of glioblastoma cells induced by miR-148a overexpression. Our findings indicate that miR-148a can suppress the malignant phenotype of glioblastoma by targeting ITGA9 and identify ITGA9 as a potential therapeutic target for glioblastoma.
Condition monitoring for overhead power lines is critical for power transmission networks to improve their reliability, detect potential problems in the early stage, and ensure the utilization of the ...transmitting full capacity. Energy harvesting can be an effective solution for autonomous self-powered wireless sensors. In this paper, a novel bow-tie-shaped coil is proposed, which is placed directly under overhead power lines to scavenge the magnetic field energy. Compared to the conventional method by mounting the energy harvester on the power lines, this approach provides more flexibility and space to power bigger sensors such as the weather station. As the harvesting coil cannot entirely enclose the power lines, the demagnetization factor that is closely related to the core geometry should be considered and optimized. Thus a new bow-tie-shape core is designed to produce a much lower demagnetization factor (hence more power) than that of the conventional solenoid. The selection of core material is studied and found that Mn-Zn ferrite is the most suitable core material because it greatly reduces the eddy current losses and also has high permeability. Experiment results show that the bow-tie coil could have a power density of 1.86 μW/cm 3 when placed in a magnetic flux density of 7 μT rms . This value is 15 times greater than the reported results under the same condition. If a longer bow-tie coil with more turns is placed in a magnetic flux density of 11μT rms , the produced power density is 103.5 μW/cm 3 , which is comparable to a solar panel working during a cloudy day. Thus, the proposed solution is a very efficient and attractive method for harvesting the magnetic field energy for a range of monitoring applications.
Abstract
We have conducted a line survey toward Orion KL using the
Q
-band receiver of the Tianma 65 m radio telescope (TMRT), covering 34.8–50 GHz with a velocity resolution between 0.79 and 0.55 km ...s
−1
, respectively. The observations reach a sensitivity of the level of 1–8 mK, proving that the TMRT is sensitive for conducting deep-line surveys. In total, 597 Gaussian features are extracted. Among them, 177 radio recombination lines (RRLs) are identified, including 126, 40, and 11 RRLs of hydrogen, helium, and carbon, with a maximum Δ
n
of 16, 7, and 3, respectively. The carbon RRLs are confirmed to originate from photodissociation regions with a
V
LSR
∼ 9 km s
−1
. In addition, 371 molecular transitions of 53 molecular species are identified. Twenty-one molecular species of this survey were not firmly detected in the
Q
band by Rizzo et al., including species such as H
2
CS, HCOOH, C
2
H
5
OH,
H
2
13
CO, H
2
CCO, CH
3
CHO, CH
2
OCH
2
, HCN
υ
2
= 1, and CH
3
OCHO
υ
t
= 1. In particular, the vibrationally excited states of ethyl cyanide (C
2
H
5
CN
υ
13/
υ
21) are for the first time firmly detected in the
Q
band. NH
3
(15,15) and (16,16) are identified, and they are so far the highest transitions of the NH
3
inversion lines detected toward Orion KL. All of the identified lines can be reproduced by a radiative transfer model.
To meet the demand for novel pest management strategies to combat the development of insecticide resistance, plant essential oils may be a promising alternative source. This study investigated the ...insecticidal activity of five essential oils from the Rutaceae plant family against
Schrank (Thysanoptera: Thripidae) under laboratory conditions. The plant essential oils were citrus oil (
Blanco), Chuan-shan pepper oil (
Maxim.), zanthoxylum oil (
Maxim.), pomelo peel oil (
(Burm.) Merr.) and orange leaf oil (
(L.) Osbeck). Among the essential oils evaluated, orange leaf oil (LC
= 0.26 g/L), zanthoxylum oil (LC
= 0.27 g/L), and pomelo peel oil (LC
= 0.44 g/L) resulted in a higher gastric toxicity under laboratory conditions. The results of the pot experiment also showed that orange leaf oil (93.06 ± 3.67% at 540.00 g a.i.·hm
, 97.22 ± 1.39% at 720 g a.i.·hm
, 100.00% at 900.00 g a.i.·hm
) zanthoxylum oil (98.73 ± 1.27% at 900 g a.i.·hm
), and pomelo peel oil (100.00% at 900 g a.i.·hm
) exhibited a higher control efficacy, being the most effective against
after 7 days of treatment. The essential oil components were then identified by gas chromatography-mass spectrometry (GC-MS). The insecticidal activity of orange leaf oil, pomelo peel oil, and zanthoxylum oil could be attributed to their main constituents, such as methyl jasmonate (50.92%), D-limonene (76.96%), and linalool (52.32%), respectively. In the olfactory test, adult
were attracted by zanthoxylum oil and Chuan-shan pepper oil. We speculated that linalool might be the key signaling compound that attracts
. These results showed that orange leaf oil, zanthoxylum oil, and pomelo peel oil exhibited insecticidal activities under controlled conditions. They can be implemented as effective and low-toxicity botanical insecticides and synergistic agents against
.
Magnetostructural coupling in MnMX (M = Co or Ni, X = Si or Ge) system attracts considerable attention for the accompanied multi-magnetoresponsive effects. However, due to the large stress generated ...from the structural transformation, the alloys become shattered or powder-like, hindering the further investigation and their applications. The possible solution is to embed the MnMX powders into metal matrix. In this paper, we choose Mn0.66Fe0.34Ni0.66Fe0.34Si0.66Ge0.34 as a representative of MnMX alloy and produce Mn0.66Fe0.34Ni0.66Fe0.34Si0.66Ge0.34/Sn composite bulk by hot pressing. The magnetostructural-coupled composites exhibit an improved rate of the transformation temperature shift by magnetic field and broadened operating temperature range. Additionally, we also propose a simple formula based on the entropy-temperature diagram to calculate the isothermal entropy change, which is consistent with the results obtained by the Maxwell relation.
Abstract The James Clerk Maxwell Telescope (JCMT) Transient Survey has been monitoring eight Gould Belt low-mass star-forming regions since 2015 December and six somewhat more distant ...intermediate-mass star-forming regions since 2020 February with the Submillimeter Common User Bolometer Array 2 on board JCMT at 450 and 850 μ m and with an approximately monthly cadence. We introduce our pipeline v2 relative calibration procedures for image alignment and flux calibration across epochs, improving on our previous pipeline v1 by decreasing measurement uncertainties and providing additional robustness. These new techniques work at both 850 and 450 μ m, where version 1 only allowed investigation of the 850 μ m data. Pipeline v2 achieves better than 0.″5 relative image alignment, less than a tenth of the submillimeter beam widths. The version 2 relative flux calibration is found to be 1% at 850 μ m and <5% at 450 μ m. The improvement in the calibration is demonstrated by comparing the two pipelines over the first 4 yr of the survey and recovering additional robust variables with version 2. Using the full 6 yr of the Gould Belt survey, the number of robust variables increases by 50%, and at 450 μ m we identify four robust variables, all of which are also robust at 850 μ m. The multiwavelength light curves for these sources are investigated and found to be consistent with the variability being due to dust heating within the envelope in response to accretion luminosity changes from the central source.
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