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With the wide applications of the Internet of Things (IoT) in smart home systems, IEEE 802.11n Wireless Local Area Networks (WLANs) have become a frequently chosen communication technology due to their adaptability and affordability. In a high-density network of devices such as the smart home scenerio, a host often meets interferences from other devices and unequal Received Signal Strength (RSS) from Access Points (APs). This results in throughput unfairness/insufficiency problems between hosts communicating concurrently in WLAN. Previously, we have studied the throughput request satisfaction method to address this problem. It calculates the target throughput from measured single and concurrent throughputs of hosts and controls the actual throughput at this target one by applying traffic shaping at the AP. However, the insufficiency problem of maximizing the throughput is not solved due to interferences from other hosts. In this paper, we present an extension of the throughput request satisfaction method to maximize the throughput of a high-priority host under concurrent communications. It recalculates the target throughput to increase the actual throughput as much as possible while the other hosts satisfy the least throughput. For evaluations, we conduct experiments using the test-bed system with Raspberry Pi as the AP devices in several topologies in indoor environments. The results confirm the effectiveness of our proposal.
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The IEEE 802.11 wireless local-area network (WLAN) has been deployed around the globe as a major Internet access medium due to its low cost and high flexibility and capacity. Unfortunately, dense wireless networks can suffer from poor performance due to high levels of radio interference resulting from adjoining access points (APs). To address this problem, we studied the AP transmission power optimization method, which selects the maximum or minimum power supplied to each AP so that the average signal-to-interference ratio (SIR) among the concurrently communicating APs is maximized.However, this method requires measurements of receiving signal strength (RSS) under all the possible combinations of powers. It may need intolerable loads and time as the number of APs increases. It also only considers the use of channel bonding (CB), although non-CB sometimes achieves higher performance under high levels of interference. In this paper, we present an AP interface setup optimization method using the throughput estimation model for concurrently communicating APs. The proposed method selects CB or non-CB in addition to the maximum or minimum power for each AP. This model approach avoids expensive costs of RSS measurements under a number of combinations. To estimate the RSS at an AP from another AP or a host, the model needs the distance and the obstacles between them, such as walls. Then, by calculating the estimated RSS with the model and calculating the SIR from them, the AP interface setups for a lot of APs in a large-scale wireless network can be optimized on a computer in a very short time. For evaluation, we conducted extensive experiments using Raspberry Pi for APs and Linux PCs for hosts under 12 network topologies in three buildings at Okayama University, Japan, and Jatiya Kabi Kazi Nazrul Islam University, Bangladesh. The results confirm that the proposed method selects the best AP interface setup with the highest total throughput in any topology.
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Tree peonies (Paeonia suffruticosa Andr. and hybrids) are well-known ornamental and medicinal plants cultivated in temperate and subtropical regions around the world. From June to September 2021, severe leaf spot disease was observed on 3 tree peony cultivars ('Luoyanghong', 'Moyushenghui', 'Roufurong') in Xinxiang (35º29´N, 113º95´E) and Luoyang (34º64´N, 112º49´E), Henan Province, China. Leaf spot incidence was as high as 28% ('Luoyanghong'), 45% ('Moyushenghui') and 67% ('Roufurong'), respectively. Symptoms appeared initially as small purple spots less than 1 mm in diameter in the middle and upper parts of the leaves, and then evolved to coalescent lesions, causing brown scorch ultimately. From each cultivar, 5 diseased leaves were collected. Leaflet tissues (3-4 mm2) cut from spot margins were surface sterilized in 75% alcohol for 45 s, washed 5 times with sterile distilled water, and then cultivated on potato dextrose agar (PDA) medium at 28 °C in the dark. Eleven isolates were obtained, and colonies grown from single conidia on PDA were 80-85 mm in diameter after 10 d, with scattered small, dark-based spikes on the surface of the colonies. The aerial mycelium was cottony, dense, and dark gray near the center on the reverse side. Conidia were cylindrical to clavate, with rounded apex and rounded base, and the conidia contents were granular, 8.44-14.06×3.60-4.31 µm (mean=11.28×3.69 µm, n=40). Appressoria were mostly subglobose or with a few broad lobes, pale to medium brown, 3.36-6.72×3.35-5.60 µm (mean=5.02×4.55 µm, n=20). Based on the culture representation and conidial morphology, the isolates were characterized as Colletotrichum gloeosporioides species complex (Weir et al. 2012; Fu et al. 2019). To further identity the species, the actin (ACT), calmodulin (CAL), chitin synthase (CHS-1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and the ribosomal internal transcribed spacers (ITS) loci of isolates PSW0002, PSW0008 and PSW0009 were amplified using ACT-512F/ACT-783R, CL1C/CL2C, CHS-79F/CHS-345R, GDF/GDR, and ITS1/ITS4, primers (Weir et al. 2012; Schena et al; 2014; Kim et al. 2021; Li et al. 2021). Fifteen sequences were deposited in GenBank (ACT for OP225605, OP225606, and OP225607, CAL for OP225608, OP225609 and OP225610, CHS for OP225611, OP225612 and OP225613, GAPDH for ON321897, OP225614, and OP225615, and ITS for ON323473, OP214349 and OP214350 ), which showed 100% sequence similarity to Colletotrichum aenigma (JX009443 and JX009519 for ACT, JX009683 and JX009684 for CAL, JX009774 and JX009903 for CHS-1, JX010244 and JX009913 for GAPDH, JX010243 and JX010148 for ITS). Three isolates clustered with C. aenigma (ex-holotype culture ICMP 18608) in the multi-locus phylogenetic tree with a bootstrap value of 100%. To achieve Koch's postulates, pathogenicity was tested on 5-year-old healthy potted plants ('Luoyanghong'). Thirty leaves were inoculated with 10 µL conidial suspension (isolate PSW0002, 1×106 conidia/mL) and the controls were inoculated with sterile water. Plants were placed in a greenhouse at 28°C under conditions with 12 h photoperiod and 90% relative humidity. After 5 to 10 days, distinct spots were observed on the inoculated leaves, while the control leaves showed no symptoms. C. aenigma was reisolated from all inoculated leaves, but not from the control. C. aenigma has been reported to cause anthracnose on Pyrus pyrifolia (Weir et al. 2012), Camellia sasanqua (Chen et al. 2019), Juglans regia (Wang et al. 2020), Paeonia ostii (Ren et al. 2020), and Capsicum annuum (Sharma et al. 2022). A previous study reported C. gloeosporioides as a pathogen of anthracnose in tree peonies in China (Xuan et al. 2017), the typical symptoms were big necrotic lesions (5-10 mm diam) on leavesï¼which were significantly different from those caused by C. aenigma. To our knowledge, this is the first report of C. aenigma causing anthracnose in tree peonies in China. This finding may help to take effective control of anthracnose in tree peonies.
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As an important part of the DC micro-grid, DC solid-state transformers (DCSST) usually use a dual-loop control that combines the input equalization and output voltage loop. This strategy fails to ensure output equalization when the parameters of each dual active bridge (DAB) converter module are inconsistent, thus reducing the operational efficiency of the DCSST. To solve the above problems, a DCSST-balancing control strategy based on loop current suppression is presented. By fixing the phase-shifting angle within the bridge and adjusting the phase-shifting angle between bridges, the circulation current of each DAB converter module is reduced. Based on the double-loop control of the DAB, five controllers are nested outside each DAB submodule to achieve distributed control of the DCSST. The proposed control strategy can reduce the system circulation current with different circuit parameters of the submodules, ensure the balance of input voltage and output current of each submodule, and increase the robustness of the system. The simulation results verify the validity of the proposed method.
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BACKGROUND: Fabry disease is rare, and the diagnosis is often delayed. Here, we describe a case of Fabry disease resulting in vasculopathy of the central nervous system. Magnetic resonance (MR) black-blood sequence (three-dimensional T1 volumetric isotropic turbo spin echo acquisition), with the unique advantage of imaging the vascular wall, facilitated a clear identification of the vasculopathy. CASE PRESENTATION: A 27-year-old man visited our hospital for the treatment of " double vision 6d." After a series of examinations, the patient was diagnosed with Fabry disease, which caused vasculopathy of the central nervous system. Subsequently, the patient was treated with corticosteroids and his symptoms were attenuated. Two months after the initial treatment, the initial lesion in the vascular vessel disappeared, however, a new lesion appeared. Similarly, four months after the initial treatment, although the previous lesion disappeared, a new lesion appeared. CONCLUSIONS: This case highlights that clinicians should use MR black-blood sequence scan in a timely manner in case of young patients with migratory lesions of brain. In case of detection of a vascular lesion in combination with other systemic lesions, the possibility of Fabry disease should be considered.
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Trastornos Cerebrovasculares , Enfermedad de Fabry/diagnóstico , Adulto , Trastornos Cerebrovasculares/diagnóstico , Trastornos Cerebrovasculares/etiología , Trastornos Cerebrovasculares/patología , Trastornos Cerebrovasculares/fisiopatología , Enfermedad de Fabry/complicaciones , Femenino , Humanos , Imagen por Resonancia Magnética , MasculinoRESUMEN
BACKGROUND: Spinal cord infarction (SCI) is rarely caused by vertebral artery dissection (VAD), which is an important cause of posterior circulation stroke in young and middle-aged patients. We report the case of a middle-aged patient without obvious risk factors for atherosclerosis who had SCI from right VAD. CASE PRESENTATION: An otherwise healthy 40-year-old man presented with acute right-sided body weakness. Six days earlier, he had experienced posterior neck pain without obvious inducement. Neurologic examination revealed a right Brown-Séquard syndrome. Magnetic resonance imaging (MRI) of the head was normal. Further, cervical spine MRI showed spinal cord infarction (SCI) on the right at the C1-C3 level. Three-dimensional high-resolution MRI (3D HR-MRI) volumetric isotropic turbo spin echo acquisition (VISTA) scan showed evidence of vertebral artery dissection (VAD). The patient was significantly relieved of symptoms and demonstrated negative imaging findings after therapy with anticoagulation (AC) and antiplatelets (AP) for 3 months. CONCLUSIONS: The possibility of vertebral artery dissection (VAD) should be considered in the case of young and middle-aged patients without obvious risk factors for atherosclerosis. Furthermore the VISTA black blood sequence plays an important role in the pathological diagnosis of vertebral artery stenosis. Early correct diagnosis and active therapy are crucial to the prognosis.
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Síndrome de Brown-Séquard/etiología , Infarto/etiología , Médula Espinal/irrigación sanguínea , Disección de la Arteria Vertebral/complicaciones , Adulto , Humanos , Masculino , Médula Espinal/patología , Enfermedades de la Médula Espinal/etiologíaRESUMEN
BACKGROUND: To summarize the characteristics of primary central nervous system vasculitis from clinical, imaging, and pathological aspects by retrospective study. METHODS: From March 2015 to December 2017, the data of the inpatients of primary central nervous system vasculitis in first Hospital of Jilin University were collected, and their clinical manifestation, imaging, and pathological characteristics were analyzed by using a descriptive method. RESULTS: There were 18 patients, 10 males (55.56%) and 8 females (44.44%) separately. The age ranges from 16 years old to 49 years old, with the median age of 32 years old. There were 8 cases (44.44%) of epileptic seizure, 6 cases (33.33%) of abnormal behavior and cognition, 10 cases (55.56%) with sensorimotor abnormalities, 4 cases (22.22%) with dizziness, 4 cases (22.22%) with headache, 2 cases (11.11%) with facial pain, 2 cases (11.11%) with blurred vision, and 2 cases (11.11%) with unstable walking. Eight patients (44.44%) were identified with cerebral spinal fluid abnormalities. There were 12 cases (66.67%) with bilateral lesions and 6 cases (33.33%) with unilateral lesions, including the frontal lobe (18 cases, 100%), the parietal lobe (10 cases, 55.56%), the temporal and occipital lobe (8 cases, 44.44%). There were 12 cases (66.67%) combined with subcortical white matter involvement, 6 cases (33.33%) combined with meningeal involvement, 2 cases (11.11%) complicated with basal ganglia involvement and 2 cases (11.11%) complicated with spinal cord involvement. Most of the lesions were with unclear border (16 cases, 88.89%), 2 cases (11.11%) were with clear border. Cortical atrophy was identified in 6 cases (33.33%). There were 12 cases (66.67%) with the enhancement of the lesions and meningeal. The 3D Vessel Wall magnetic resonance imaging (VW-MRI) showed uniform thickness in all patients (18/18) with contrast enhancement of the vessel wall of the vasculitis artery. CONCLUSIONS: The clinical manifestation and imaging in primary central nervous system vasculitis are diverse. The 3D VW-MRI could achieve quantification assessment of vasculitis and provide more utility for primary angiitis of the central nervous system.
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Angiografía Cerebral/métodos , Arterias Cerebrales , Imagen de Difusión por Resonancia Magnética , Angiografía por Resonancia Magnética , Vasculitis del Sistema Nervioso Central/diagnóstico , Adolescente , Adulto , Angiografía de Substracción Digital , Biopsia , Arterias Cerebrales/diagnóstico por imagen , Arterias Cerebrales/patología , Arterias Cerebrales/fisiopatología , Niño , China , Angiografía por Tomografía Computarizada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Vasculitis del Sistema Nervioso Central/diagnóstico por imagen , Vasculitis del Sistema Nervioso Central/patología , Vasculitis del Sistema Nervioso Central/fisiopatología , Adulto JovenRESUMEN
In this study, we cloned a full-length cDNA encoding vitellogenin (Vg) in the Fujian oyster Crassostrea angulata. The complete Vg cDNA consists of 5160 nucleotides with a long open reading frame encoding 1641 amino acid residues. The deduced amino acid sequence shared high similarity with the Vgs of other mollusc, fish, nematode and arthropod species, particularly in the N-terminal region. We analyzed the spatiotemporal expression of caVg transcripts by Real-time Quantitative PCR. In common with other mollusc Vgs, the caVg gene was expressed primarily in the ovary, and the levels were 348 and 177 times higher in maturation and ripeness stages (P<0.01), respectively, than in the partially spent stage. There was negligible expression in male oysters. In situ hybridization analysis further localized caVg mRNA to the follicle cells (also named auxiliary cells) surrounding the oocytes in the ovary. Moreover, in vivo waterborne exposure experiments in early gametogenesis oysters showed that estradiol-17ß (E2) administration resulted in a significant increase in caVg mRNA expression. We conclude that caVg is synthesized in the follicle cell surrounding the vitellogenic oocyte in C. angulata, and directly passed to oocytes through the extracellular space without mediation through hemolymph. Also, we hypothesize that this process is mediated by E2 in a dose dependent.
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Crassostrea/metabolismo , Estradiol/metabolismo , Ovario/metabolismo , Vitelogeninas/biosíntesis , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Crassostrea/citología , Crassostrea/efectos de los fármacos , Crassostrea/genética , ADN Complementario/genética , Estradiol/farmacología , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Datos de Secuencia Molecular , Folículo Ovárico/citología , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/metabolismo , Ovario/citología , Ovario/efectos de los fármacos , Filogenia , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reproducción/genética , Testículo/efectos de los fármacos , Testículo/metabolismo , Factores de Tiempo , Vitelogeninas/química , Vitelogeninas/genéticaRESUMEN
Cotton fabric is extensively utilized due to its numerous applications, but the flammability associated with cotton fabric poses potential security risks to individuals. A halogen-free efficient flame retardant named poly [(tetramethylcyclosiloxyl spirocyclic pentaerythritol)-piperazin phosphate] (PCPNTSi) was developed to consolidate the fire retardance of cotton fabrics. After PCPNTSi treatment, the limiting oxygen index (LOI) of cotton fabric with 30 % weight gain (CP3) was raised to 32.8 %. In the vertical flammability test (VFT), CP3 has self-extinguished performance with a char length of 8.7 cm. The heat release rate (HRR) of cotton fabric with 20 % weight gain (CP2) is 78.8 % lower than that of pure cotton fabric (CP0). In addition, the total smoke release (TSP) of CP2 is 41.7 % lower than that of CP0, indicating PCPNTSi gives cotton fabric a good capability to inhibit smoke release. Finally, the possible flame retardant mechanism was discussed by the data of scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray photoelectron spectroscopy (XPS), Fourier Transform infrared spectroscopy (FT-IR) and thermogravimetric infrared spectroscopy (TG-IR). The results show that PCPNTSi is an intumescent flame retardant acting in both gas phase and solid phase.
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Fibra de Algodón , Retardadores de Llama , Retardadores de Llama/análisis , Fibra de Algodón/análisis , Nitrógeno/química , Textiles/análisisRESUMEN
Pollen morphology, pollen vigor, and long-term pollen storage are critical for plant cross-breeding and genetic improvement of Exochorda racemosa. We developed a protocol for viability determination and storage of E. racemosa pollen for breeding new varieties. The medium components for E. racemosa pollen germination was optimized by using an Orthogonal Assay Test Strategy (OATS). The germination rates of E. racemosa pollen were investigated after storing at different temperatures and different storage periods. The size of E. racemosa pollen was medium with three germination ditches, and the sculptural type of pollen was striate. Red ink and 2,3,5-triphenyl tetrazolium chloride (TTC) can effectively distinguish viable pollen from the unviable pollen of E. racemosa. The most suitable medium (CK2) for E. racemosa was composed of 150 g· L-1 sucrose, 100 mg·L-1 boric acid, 150 mg· L-1 Ca(NO3)2 and 50 mg· L-1 GA3. Low-temperature stress produced the greater inhibition of pollen tube growth compared with high-temperature conditions. The CK2 medium at pH 6.5 resulted in the highest pollen germination rate and most extended pollen tube length. The optimal temperature for storage of dried pollen was -80°C (P < 0.01), and the germination rate was 53.60% after storage for 390 days. Thawing in a 35°C water bath produced the best viability of E. racemosa pollen after storage at -20°C and -80°C. The short-term storage of E. racemosa fresh pollen at 4°C was better than that at -20°C and -80°C (P < 0.01). It is possible to evaluate pollen quality and store pollen grains for E. racemosa by the parameters defined in this study.
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In this work, sol-gel and chemical etching methods are adopted to synthesize zinc hydroxystannate materials. Cubic tin dioxide and zinc stannate composite materials with a definite structure are successfully prepared at varied annealing temperatures and times by using the synthesized zinc hydroxystannate as a sacrificial template. After a gas sensing test, tin dioxide and zinc stannate composite samples etched at 650 °C and annealed for 4 h exhibit a strong response and outstanding selectivity to hydrogen peroxide. Furthermore, the samples prepared under such conditions demonstrate long-term stability, and also a specified level of tolerance after the humidity stability test. Moreover, because of the simple preparation method and rapid detection of hydrogen peroxide, it is worth noting that samples prepared following the etching process at the 650 °C annealing temperature for 4 h exhibit the significant benefits of tin dioxide and zinc stannate composites. In this modern era, this research emphasizes the sample's potential for the rapid identification and detection of hydrogen peroxide.
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In this study, the complete chloroplast genome of Acer paihengii, a tree species native to China, was sequenced and assembled through second-generation sequencing. The complete chloroplast genome of A. paihengii is 155,967 bp in length with a typical quadripartite structure, encompassing 130 genes including 85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Phylogenetic analysis of 22 related species indicated that A. paihengii was more closely related to Acer coriaceifolium and Acer sino-oblongum.
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During urbanization in developing countries, fragmentation of green infrastructure due to increasing populations and the expansion of construction land leads to an extremely serious imbalance between the supply and demand for urban ecosystem services. In this study, the central city of Zhengzhou, a central city in central China, was selected as the study area and the excessive demand for six ecosystem services, namely, air purification, flood regulation, heat regulation, hydrological regulation, CO2 sequestration and recreational services, was quantitatively evaluated. The entropy method was used to calculate the weights of various ecosystem services, and spatial overlay analysis was performed to obtain the comprehensive ecosystem service excessive demand. Finally, bivariate spatial autocorrelation analysis was used to explore the response of population density to comprehensive excessive demand for ESs. The results of this study indicate that: (1) The most prevalent need is for more CO2 regulation service throughout the study area. (2) Except for hydrological regulation service, the spatial distribution of the remaining highly excessive ecosystem service demands are mostly concentrated in old neighborhoods. (3) Of the six excessively demanded economic services, rainwater regulation obtained the greatest weight, reflecting the poor urban infrastructure configuration for countering the rapidly increasing threat of flooding caused by climate change in the city. (4) The comprehensive ecosystem service excessive demand results show that there are eight priority green infrastructure implementation blocks in the central city of Zhengzhou. (5) There were three agglomeration types between population density and comprehensive excessive demand for ESs: high-high type, low-high type and low-low type. The spatial distribution characteristics of population density and comprehensive ES demand are positively correlated. The results of this study could help to provide information for decision making when delineating the priority areas and types of green infrastructure implementation in developing cities.