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1.
Sensors (Basel) ; 23(10)2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37430620

RESUMEN

As a basic task and key link of space situational awareness, space target recognition has become crucial in threat analysis, communication reconnaissance and electronic countermeasures. Using the fingerprint features carried by the electromagnetic signal to recognize is an effective method. Because traditional radiation source recognition technologies are difficult to obtain satisfactory expert features, automatic feature extraction methods based on deep learning have become popular. Although many deep learning schemes have been proposed, most of them are only used to solve the inter-class separable problem and ignore the intra-class compactness. In addition, the openness of the real space may invalidate the existing closed-set recognition methods. In order to solve the above problems, inspired by the application of prototype learning in image recognition, we propose a novel method for recognizing space radiation sources based on a multi-scale residual prototype learning network (MSRPLNet). The method can be used for both the closed- and open-set recognition of space radiation sources. Furthermore, we also design a joint decision algorithm for an open-set recognition task to identify unknown radiation sources. To verify the effectiveness and reliability of the proposed method, we built a set of satellite signal observation and receiving systems in a real external environment and collected eight Iridium signals. The experimental results show that the accuracy of our proposed method can reach 98.34% and 91.04% for the closed- and open-set recognition of eight Iridium targets, respectively. Compared to similar research works, our method has obvious advantages.

2.
Sensors (Basel) ; 21(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33668792

RESUMEN

A quality evaluation of precise products for BDS-3 constellations is presented for the first time in this contribution. Then, the tropospheric delay retrieval and positioning performance of BDS-3 precise point positioning (PPP) solutions using the precise products (gbm, wum, iac, sha, cnt) with observations from 24 stations from DOY 280 to 317 in 2020 was comprehensively investigated. The orbit comparisons present consistencies of 0.09-0.22 m for the C19-C37 satellites and of 0.5-1.2 m for the C38-C46 satellites among the final products. The standard deviation (STD) values of the clock differences of iac showed the best agreement with those of gbm, followed by wum, sha. The clock differences performance of cnt was the worst. For BDS-3 PPP solutions with five Analysis centers (ACs) products, the median convergence times of static PPP mode incorporating the gbm, wum, iac, sha, and cnt products were 31.0, 33.5, 34.5, 37.8, and 72.0 min, respectively; the median convergence times of kinematic PPP model incorporating the same products were 40.5, 41.0, 50.5, 55.0, and 94.0 min, respectively. The positioning accuracies in the static and kinematic modes were approximately 1-4 cm, 2-6 cm in the horizontal and vertical components, respectively. With the final products in kinematic mode, the performance of PPP with real-time products (cnt) is poorer than all PPP with final products. The median of ZTD accuracies of the five products gbm, wum, iac, sha, and cnt were 7.84, 7.58, 7.04, 7.19, and 10.1 mm, respectively, and the accuracy differences were very small among five AC products (gbm, wum, iac, sha).

3.
Sensors (Basel) ; 21(1)2020 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-33374254

RESUMEN

The high precision positioning can be easily achieved by using real-time kinematic (RTK) and precise point positioning (PPP) or their augmented techniques, such as network RTK (NRTK) and PPP-RTK, even if they also have their own shortfalls. A reference station and datalink are required for RTK or NRTK. Though the PPP technique can provide high accuracy position data, it needs an initialisation time of 10-30 min. The time-relative positioning method estimates the difference between positions at two epochs by means of a single receiver, which can overcome these issues within short period to some degree. The positioning error significantly increases for long-period precise positioning as consequence of the variation of various errors in GNSS (Global Navigation Satellite System) measurements over time. Furthermore, the accuracy of traditional time-relative positioning is very sensitive to the initial positioning error. In order to overcome these issues, an improved time-relative positioning algorithm is proposed in this paper. The improved time-relative positioning method employs PPP model to estimate the parameters of current epoch including position vector, float ionosphere-free (IF) ambiguities, so that these estimated float IF ambiguities are used as a constraint of the base epoch. Thus, the position of the base epoch can be estimated by means of a robust Kalman filter, so that the position of the current epoch with reference to the base epoch can be obtained by differencing the position vectors between the base epoch and the current one. The numerical results obtained during static and dynamic tests show that the proposed positioning algorithm can achieve a positioning accuracy of a few centimetres in one hour. As expected, the positioning accuracy is highly improved by combining GPS, BeiDou and Galileo as a consequence of a higher amount of used satellites and a more uniform geometrical distribution of the satellites themselves. Furthermore, the positioning accuracy achieved by using the positioning algorithm here described is not affected by the initial positioning error, because there is no approximation similar to that of the traditional time-relative positioning. The improved time-relative positioning method can be used to provide long-period high precision positioning by using a single dual-frequency (L1/L2) satellite receiver.

4.
Sensors (Basel) ; 20(16)2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32824205

RESUMEN

The orbital maneuvers of the global navigation satellite system (GNSSs) have a significant influence on the performance of the precise positioning, navigation, and timing (PNT) services. Because the Chinese BeiDou Navigation Satellite System (BDS) has three types of satellites in the geostationary orbit (GEO), inclined geosynchronous orbit (IGSO), and medium earth orbit (MEO) maneuvers occur more frequently. Thus, it is essential to determine an effective approach for the detection of orbital maneuvers. This study proposes a method for the detection of orbital maneuvers using epoch-differenced carrier phase observations and broadcast ephemeris data. When using the epoch-differenced velocity estimation as a basic data solution model, the time discrimination and satellite identification factors are defined and used for the real-time detection of the beginning and the pseudorandom noise code (PRN) of satellites. The datasets from four GNSS stations (WUH1, BJF1, POHN, CUT0) from the year 2016 were collected and analyzed. The validations showed that the beginning, the PRN of the orbital maneuver of the satellite can be precisely detected in real time for all GEO, IGSO, and MEO satellites, and the detected results also showed good consistency, with the beginning time at a difference of 1-2 min across different stations. The proposed approach was observed to be more sensitive, and the detected beginning time was about 30 min earlier than the single point positioning approach when the high-precision carrier phase observation was used. Thus, orbital maneuvering can be accurately detected by the proposed method. It not only improves the utilization of the collected data but also improves the performance of PNT services.

5.
Sensors (Basel) ; 20(5)2020 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-32121438

RESUMEN

The satellite-induced code bias variation of geostationary satellite orbit satellites and medium earth orbit satellites of the second-generation BeiDou Navigation Satellite System (BDS-2) exceeds 1 m, which severely affects the accuracy and stability of the ambiguity resolution and high-precision positioning. With the development of the third-generation BDS (BDS-3) with a new system design and new technology, analysis of the satellite-induced code variation characteristics of BDS-3 has become increasingly important. At present, many scholars have explored the satellite-induced code bias of BDS-3, but most of them focus on BDS-3 experimental satellites via normal geodetic antenna. Compared to normal geodetic antenna, the 40-m dish antenna from the National Time Service Center can accurately detect satellite-induced code variations with low noise and high gain. Thus, observational data from fifteen BDS-3 medium earth orbit satellites are collected with the B1I/B2b/B3I/B1C/B2a frequency bands on the day of year (DOY) 199-206 in 2019, the PRN numbers of which are C19/C20/C21/C22/C23/C24/C25/C26/C27/C28/C30/C32/C33 /C35/C37, via the 40 m dish antenna to analyze the code bias variation characteristics. The results show that the obvious satellite-induced elevation­dependent code bias variations exist in the B1I/B2b/B3I/B1C/B2a frequency bands of C28, compared with other satellites. Similarly, the multipath (MP) combination of B3I has an obvious elevation­dependent variation within a range of 0.1 m for C21/C24/C27/C28/C37 and elevation­dependent variation of the B2a and B2b frequency bands also exists in most satellites with a range of 0.1 m. However, the MP combination values of some satellites are asymmetric with respect to elevation, which is different from BDS-2 satellites and especially obvious for BDS-3 satellites B1I and BIC frequency bands with elevation­dependent variations of 0.2 m, indicating that the code bias variation is not uniquely related to elevation, especially for the B1I/BIC frequency bands. What's more, the satellite-induced code bias variation of the BDS-3 satellites is greatly reduced compared with that of the BDS-2 satellites. In addition, the similar code bias variation appears at the Xia1 station with a normal geodetic antenna of B1I/B1C/B3I/B2a/B2b of C21, B3I/B2a/B2b of C24 and B2b of C28 among B1I/B1C/B3I/B2a/B2b of C21/C24/C27/C28/C37. The influence of the BDS-3 satellite-induced elevation­dependent code bias on precision positioning and ambiguity fixing is worth further study using different antennas or receivers.

6.
Turk J Med Sci ; 49(3): 928-938, 2019 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-31122000

RESUMEN

Background/aim: Diabetic vascular smooth muscle cells (VSMCs) are characterized by increased proliferation and migration. Small noncoding microRNAs (miRNAs) have been considered critical modulators of the VSMC phenotypic switch after an environmental stimulus. However, microRNA in high glucose-induced proinflammation and its atherogenic effect is still ambiguous. Materials and methods: The technique of qRT-PCR was used to examine the expression of miR-9 in VSMCs. The downstream signaling protein relative to miR-9 regulation, Krüppel-like factor 5, and some marker genes of contractile VSMCs were analyzed by western blotting and qRT-PCR. Luciferase reporter assay was used to detect the expression of KLF5, which is regulated by miR-9. To examine the function of a miR-9 inhibitor in VSMC proliferation and migration, VSMC proliferation and migration assays were performed. Results: Reduced transcriptional levels of miR-9 and expression of specific genes of contractile VSMCs were observed in the SMC cell line C-12511 treated with high glucose and SMCs, which were isolated from db/db mice. Moreover, the activity of KLF5 3'-UTR was dramatically reduced by a miR-9 mimic and increased by a miR-9 inhibitor. The proliferation and migration of SMCs were reduced by the miR-9 mimic. Conclusion: miR-9 inhibits the proliferation and migration of SMC by targeting KLF5 in db/db mice.


Asunto(s)
Diferenciación Celular/genética , Factores de Transcripción de Tipo Kruppel/genética , MicroARNs/genética , Músculo Liso Vascular/citología , Animales , Línea Celular , Movimiento Celular/genética , Proliferación Celular/genética , Regulación hacia Abajo/genética , Células HEK293 , Humanos , Factores de Transcripción de Tipo Kruppel/metabolismo , Masculino , Ratones , Ratones Transgénicos , MicroARNs/metabolismo , Fenotipo
7.
Sensors (Basel) ; 18(4)2018 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-29596330

RESUMEN

This study proposes two models for precise time transfer using the BeiDou Navigation Satellite System triple-frequency signals: ionosphere-free (IF) combined precise point positioning (PPP) model with two dual-frequency combinations (IF-PPP1) and ionosphere-free combined PPP model with a single triple-frequency combination (IF-PPP2). A dataset with a short baseline (with a common external time frequency) and a long baseline are used for performance assessments. The results show that IF-PPP1 and IF-PPP2 models can both be used for precise time transfer using BeiDou Navigation Satellite System (BDS) triple-frequency signals, and the accuracy and stability of time transfer is the same in both cases, except for a constant system bias caused by the hardware delay of different frequencies, which can be removed by the parameter estimation and prediction with long time datasets or by a priori calibration.

8.
Int Heart J ; 59(1): 170-179, 2018 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-29332916

RESUMEN

It has been shown that microRNAs (miRNAs) greatly affect the functions of vascular smooth muscle cells (VSMC), but the effects of mRNAs under diabetic conditions remain unclear.Using a model of diabetic db/db mice, we studied the functions of microRNA-135a (miR-135a) during VSMC dysfunction.Compared to control WT mice, miR-135a expression in VSMC was significantly increased while the level of forkhead box O1 (FOXO1) protein decreased significantly. After transfecting miR-135a mimics into VSMC, the expression of FOXO1 was decreased, while cyclooxygenase-2 (COX-2) and monocyte chemoattractant protein-1 (MCP-1) expression levels were increased, thus promoting the interaction between monocytes and WT VSMC. On the other hand, transfection of an miR-135a inhibitor reversed the activated interaction between monocytes and db/db VSMC. The pro-inflammatory responses could also be enhanced by using siRNAs to silence the FOXO1 gene in WT VSMC, suggesting a negative regulatory role of FOXO1. FOXO1 siRNAs and miR-135a mimics could both enhance the transcriptional activity of COX-2 promoter. Using chromatin immunoprecipitation, we found that in db/db VSMC, the occupancy in promoter regions of inflammatory genes by FOXO1 was reduced.miR-135a increased the inflammatory responses of VSMC involved in complications of vascular diseases by downregulating the expression of FOXO1.


Asunto(s)
Regulación hacia Abajo , Proteína Forkhead Box O1/genética , Regulación de la Expresión Génica , Inflamación/genética , MicroARNs/genética , Miocitos del Músculo Liso/metabolismo , Enfermedades Vasculares/genética , Animales , Western Blotting , Células Cultivadas , ADN/genética , Modelos Animales de Enfermedad , Proteína Forkhead Box O1/biosíntesis , Inmunohistoquímica , Inflamación/metabolismo , Inflamación/patología , Masculino , Ratones , Ratones Noqueados , MicroARNs/biosíntesis , Miocitos del Músculo Liso/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Enfermedades Vasculares/metabolismo , Enfermedades Vasculares/patología
9.
Sensors (Basel) ; 17(3)2017 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-28273814

RESUMEN

In this study, a unified model for BeiDou Navigation Satellite System (BDS) wide area and local area augmentation positioning based on raw observations has been proposed. Applying this model, both the Real-Time Kinematic (RTK) and Precise Point Positioning (PPP) service can be realized by performing different corrections at the user end. This algorithm was assessed and validated with the BDS data collected at four regional stations from Day of Year (DOY) 080 to 083 of 2016. When the users are located within the local reference network, the fast and high precision RTK service can be achieved using the regional observation corrections, revealing a convergence time of about several seconds and a precision of about 2-3 cm. For the users out of the regional reference network, the global broadcast State-Space Represented (SSR) corrections can be utilized to realize the global PPP service which shows a convergence time of about 25 min for achieving an accuracy of 10 cm. With this unified model, it can not only integrate the Network RTK (NRTK) and PPP into a seamless positioning service, but also recover the ionosphere Vertical Total Electronic Content (VTEC) and Differential Code Bias (DCB) values that are useful for the ionosphere monitoring and modeling.

10.
Theor Appl Genet ; 129(5): 1035-44, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26883042

RESUMEN

KEY MESSAGE: A novel R gene was mapped to a locus on chromosome 11 from 30.42 to 30.85 Mb, which was proven to be efficient in the improvement of rice blast resistance. Rice blast is a devastating fungal disease worldwide. The use of blast resistance (R) genes is the most important approach to control the disease in rice breeding. In the present study, we finely mapped a novel resistance gene Pi65(t), conferring a broad-spectrum resistance to the fungus Magnaporthe oryzae, using bulked segregant analysis in combination with next-generation sequencing technology. Segregation in a doubled haploid (DH) population and a BC1F2 population suggested that resistance to blast in Gangyu129 was likely conferred by a single dominant gene, designated Pi65(t); it was located on chromosome 11 from 30.20 to 31.20 Mb using next-generation sequencing. After screening recombinants with newly developed molecular markers, the region was narrowed down to 0.43 Mb, flanked by SNP-2 and SNP-8 at the physical location from 30.42 to 30.85 Mb based on the Nipponbare reference database in build 5. Using the software QTL IciMapping, Pi65(t) was further mapped to a locus between InDel-1 and SNP-4 with genetic distances of 0.11 and 0.98 cM, respectively. Within this region, 4 predicted R genes were found with nucleotide binding site and leucine-rich repeat (NBS-LRR) domains. We developed molecular markers to genotype 305 DH lines and found that InDel-1 was closely linked with Pi65(t). Using InDel-1, a new rice variety Chuangxin1 containing Pi65(t) was developed, and it is highly resistant to rice blast and produces a high yield in Liaoning province of China. This indicated that Pi65(t) could play a key role in the improvement of rice blast resistance.


Asunto(s)
Mapeo Cromosómico , Resistencia a la Enfermedad/genética , Magnaporthe , Oryza/genética , Enfermedades de las Plantas/genética , ADN de Plantas/genética , Genes de Plantas , Ligamiento Genético , Marcadores Genéticos , Secuenciación de Nucleótidos de Alto Rendimiento , Oryza/microbiología , Fenotipo , Fitomejoramiento , Enfermedades de las Plantas/microbiología , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN
11.
Sci Total Environ ; 951: 175462, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39142403

RESUMEN

By analyzing the force-electric properties of rock-filled concrete under uniaxial compression, the precursor information and characteristics of deformation and failure of rock-filled concrete can be mastered, and the reliability and safety of rock-filled concrete structures at an early age can be ensured. This study investigated four variations of model rock-filled concrete, each with a distinct rock-filled ratio. Using the two-electrode alternating current test method, we analyzed the electrical resistivity properties of rock-filled concrete under uniaxial compression at various curing ages (1 d, 3 d, 7 d, 14 d, and 28 d). Additionally, the microscopic pore structure was examined using low-field nuclear magnetic resonance technology. The results showed that with increasing curing age or rock-filled ratio, the compressive strength and electrical resistivity of rock-filled concrete showed a nonlinear growth trend. In contrast, the porosity showed a nonlinear decrease, with the internal pore structure gradually becoming more refined. A mathematical model was established to describe the electrical resistivity of rock-filled concrete at various curing ages and rock-filled ratios. During uniaxial compression, the electrical resistivity of rock-filled concrete followed a pattern of rapid decline, slow decline, stable, and slow increase with strain. These phases corresponded to the development of internal pores and cracks and changes in the crack resistance performance of the rockfill skeleton in the concrete. Moreover, a mathematical equation was formulated to elucidate the relationship among the damage variable, the rock-filled ratio, and the electrical resistivity of model rock-filled concrete, thereby enabling the prediction of the extent of damage to the model rock-filled concrete under stress conditions.

12.
Plant Sci ; : 112246, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39304072

RESUMEN

NLRs are a group of specific plant receptors that recognizes effectors secreted by pathogens, activates downstream immune responses, and confers resistance to pathogens. Despite variations, the functions of some NLR genes may be conserved across species, but their role in sorghum remains unclear. In this study, we investigated the stunted and yellow ripple leaf mutant sbyr1 from sorghum BTx623. Map-based cloning revealed that SbYR1 was annotated as a coiled-coil NLR with three conserved domains, namely, RX-CC, NB-ARC, and LRR, with a Thr4Met mutation in the CC domain. Inoculation experiments revealed that the sbyr1 mutation enhanced tolerance to head smut disease in sorghum. To further verify the function of SbYR1, we analysed the transcriptomes and metabolomes of the shoots of sbyr1 and BTx623. The results indicated that both the DEGs and the DAMs were enriched in secondary metabolic pathways, such as the flavonoid, JA, and ABA pathways. The increased contents of JA and ABA as a downstream effect of sbyr1 suppressed growth, whereas the application of exogenous inhibitors of JA and ABA inhibited the endogenous hormones and thus caused sbyr1 to grow productively. Overexpression and homologous gene knockout in rice confirmed that sbyr1 affects plant growth and development. In conclusion, our study revealed that a CC domain mutation in SbYR1 influences plant growth and plays a role in resistance to head smut disease and downstream secondary metabolism. KEY MESSAGE: •The Thr4Met mutation in the coiled-coil domain of the NLR receptor SbYR1 coordinates plant growth and stress tolerance in sorghum.

13.
Environ Sci Pollut Res Int ; 31(25): 37496-37519, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38777974

RESUMEN

The water retention curve (WRC) of municipal solid waste (MSW) is the important hydraulic parameter for the study of unsaturated seepage analysis in landfills. Due to the compressibility and degradability of the waste, the search for a method to quickly and accurately test its water retention curve (WRC) is a current problem that needs to be solved. In this paper, considering the volume change of the waste specimens in test, the test principle of centrifuge testing of WRC is corrected to make it applicable to the testing of waste WRC. In addition, the WRCs of 20 MSW specimens with typical landfill compositions and porosities are measured using the corrected centrifuge test. The effects of compositions and porosities of waste specimens on WRC parameters were analyzed. The results are summarized as follows. Disregarding the height reduction of specimens resulted in overestimated matric suction values and underestimating volume water content values. By comparing uncorrected and corrected values, the maximum difference of the matric suction and volumetric water content reach 233 kPa and 11%, respectively. This study can provide a reference for accurately measuring the WRC of MSW using a centrifuge. For the waste specimen without kitchen and yard waste, composition had less of an effect on the WRC of waste compared to porosity. The effect of the content of the non-absorbable fraction on the residual volumetric water content θr and the parameter nv in the van Genuchten model was significant. The initial porosity n had a great effect on the parameter α.


Asunto(s)
Centrifugación , Eliminación de Residuos , Residuos Sólidos , Agua , Agua/química , Instalaciones de Eliminación de Residuos , Porosidad
14.
PeerJ ; 12: e17438, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38818455

RESUMEN

Background: The identification and analysis of allelic variation are important bases for crop diversity research, trait domestication and molecular marker development. Grain tannin content is a very important quality trait in sorghum. Higher tannin levels in sorghum grains are usually required when breeding varieties resistant to bird damage or those used for brewing liquor. Non-tannin-producing or low-tannin-producing sorghum accessions are commonly used for food and forage. Tan1 and Tan2, two important cloned genes, regulate tannin biosynthesis in sorghum, and mutations in one or two genes will result in low or no tannin content in sorghum grains. Even if sorghum accessions contain dominant Tan1 and Tan2, the tannin contents are distributed from low to high, and there must be other new alleles of the known regulatory genes or new unknown genes contributing to tannin production. Methods: The two parents 8R306 and 8R191 did not have any known recessive alleles for Tan1 and Tan2, and it was speculated that they probably both had dominant Tan1 and Tan2 genotypes. However, the phenotypes of two parents were different; 8R306 had tannins and 8R191 had non-tannins in the grains, so these two parents were constructed as a RIL population. Bulked segregant analysis (BSA) was used to determine other new alleles of Tan1 and Tan2 or new Tannin locus. Tan1 and Tan2 full-length sequences and tannin contents were detected in wild sorghum resources, landraces and cultivars. Results: We identified two novel recessive tan1-d and tan1-e alleles and four recessive Tan2 alleles, named as tan2-d, tan2-e, tan2-f, and tan2-g. These recessive alleles led to loss of function of Tan1 and Tan2, and low or no tannin content in sorghum grains. The loss-of-function alleles of tan1-e and tan2-e were only found in Chinese landraces, and other alleles were found in landraces and cultivars grown all around the world. tan1-a and tan1-b were detected in foreign landraces, Chinese cultivars and foreign cultivars, but not in Chinese landraces. Conclusion: These results implied that Tan1 and Tan2 recessive alleles had different geographically distribution in the worldwide, but not all recessive alleles had been used in breeding. The discovery of these new alleles provided new germplasm resources for breeding sorghum cultivars for food and feed, and for developing molecular markers for low-tannin or non-tannin cultivar-assisted breeding in sorghum.


Asunto(s)
Alelos , Sorghum , Taninos , Genes de Plantas/genética , Genes Recesivos/genética , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sorghum/genética , Sorghum/metabolismo , Taninos/genética , Taninos/metabolismo
15.
Genes (Basel) ; 14(10)2023 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-37895323

RESUMEN

To investigate the cold response mechanism and low temperature regulation of flowering in tulips, this study identified 32 MADS-box transcription factor family members in tulips based on full-length transcriptome sequencing, named TgMADS1-TgMADS32. Phylogenetic analysis revealed that these genes can be divided into two classes: type I and type II. Structural analysis showed that TgMADS genes from different subfamilies have a similar distribution of conserved motifs. Quantitative real-time PCR results demonstrated that some TgMADS genes (e.g., TgMADS3, TgMADS15, TgMADS16, and TgMADS19) were significantly upregulated in buds and stems under cold conditions, implying their potential involvement in the cold response of tulips. In summary, this study systematically identified MADS family members in tulips and elucidated their evolutionary relationships, gene structures, and cold-responsive expression patterns, laying the foundation for further elucidating the roles of these transcription factors in flowering and the cold adaptability of tulips.


Asunto(s)
Tulipa , Tulipa/genética , Tulipa/metabolismo , Filogenia , Proteínas de Dominio MADS/metabolismo , Genoma de Planta , Factores de Transcripción/genética
16.
Plant Sci ; 327: 111556, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36481362

RESUMEN

Sorghum is one of the five most productive crops worldwide, but its yield is seriously limited by phosphate (Pi) availability. Although inorganic Pi signalling is well studied in Arabidopsis and rice, it remains largely unknown in sorghum. The sorghum sbpho2 mutant was identified, showing leaf necrosis and short roots. Map-based cloning identified SbPHO2 as Sobic.009G228100, an E2 conjugase gene that is a putative orthologue of the PHO2 genes in rice and Arabidopsis, which play important roles in Pi signalling. Pi starvation experiments and transformation of SbPHO2 into the rice ospho2 mutant further revealed that SbPHO2 is likely involved in Pi accumulation and root architecture alteration in sorghum. qRTPCR results showed that SbPHO2 was expressed in almost the entire plant, especially in the leaves. Furthermore, some typical Pi starvation-induced genes were induced in sbpho2 even under Pi-sufficient conditions, including Pi transporters, SPXs, phosphatases and lipid composition alteration-related genes. In addition to P accumulation in the shoots of sbpho2, concentrations of N, K, and other metal elements were also altered significantly in the sbpho2 plants. Nitrate uptake was also suppressed in the sbpho2 mutant. Consistent with this finding, the expression of several nitrate-, potassium- and other metal element-related genes was also altered in sbpho2. Furthermore, the results indicated that N-dependent control of the P starvation response is regulated via SbPHO2 in sorghum. Our results suggest that SbPHO2 participates in the regulation of the absorption of multiple nutrients, although PHO2 is a crucial and conserved component of Pi starvation signalling.


Asunto(s)
Sorghum , Transporte Biológico , Regulación de la Expresión Génica de las Plantas , Nitratos/metabolismo , Fosfatos/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Plantas/metabolismo , Sorghum/genética , Sorghum/metabolismo , Proteínas de Plantas
17.
Zhonghua Nei Ke Za Zhi ; 51(12): 962-5, 2012 Dec.
Artículo en Zh | MEDLINE | ID: mdl-23327958

RESUMEN

OBJECTIVE: To investigate the effects of ω-3 fish oil lipid emulsion via vein on the inflammatory response, immune and organ function in patients with severe acute pancreatitis. METHODS: A total of 53 patients with severe acute pancreatitis were randomized into conventional therapy plus fish oil group (FO group) and conventional therapy group (CON group). The patients in FO group were treat with ω-3 fish oil lipid emulsion (0.2 g×kg(-1)×d(-1), 10%) based on conventional therapy for 14 days. The level of C-reactive protein (CRP), TG and TC were detected before treatment and at day 7 and day 14 after treatment. CD(4)(+), CD(4)(+)/CD(8)(+) and C(3), C(4) were also detected at day 1 and day 14 after treatment. At the same time, acute physiology and chronic health evaluation II score (APACHEII score), intra-abdominal pressure, negative fluid balance time, enteral nutrition start-time and ICU stay time were observed and recorded. RESULTS: Forty-five out of 53 patients were finally recruited into results statistics. The level of CD(4)(+), CD(4)(+)/CD(8)(+) and C(3) at day 14 after treatment in FO groups improved significantly than that in the CON group (P < 0.05). The levels of CRP, intra-abdominal pressure and APACHE II score at day 7 and day 14 in FO group descended more obviously than that in the CON group (P < 0.05). The negative liquid balance time in FO group (3.55 ± 0.86)days was obvious shorter than that in CON group (4.61 ± 1.12) days, while enteral nutrition start-time (3.86 ± 1.17) days was significantly earlier compared with CON group (5.30 ± 1.61) days (P < 0.05), however ICU stay time and 28 days mortality rate had no significant difference between the two groups. CONCLUSIONS: ω-3 fish oil lipid emulsion can decrease the inflammatory response and the negative liquid balance time, improve the immune function and restore bowel function in severe acute pancreatitis patients. Therefore, it maybe provide a new and effective means for severe acute pancreatitis.


Asunto(s)
Ácidos Grasos Omega-3/uso terapéutico , Inflamación/tratamiento farmacológico , Pancreatitis/patología , Pancreatitis/fisiopatología , APACHE , Enfermedad Aguda , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pancreatitis/terapia , Resultado del Tratamiento
18.
Front Cardiovasc Med ; 9: 855053, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35571169

RESUMEN

Background: Serum chloride was recently found to be associated with prognosis of heart failure in western countries. However, the evidence was scarce in Asia. We aimed to investigated the relationship between serum chloride and clinical outcomes in a Chinese cohort with hospitalized heart failure. Methods: We retrospectively analyzed the data from PhysioNet, involving 1996 patients who were admitted with heart failure between December 2016 and June 2019. Outcome was a composite endpoint of all-cause death or rehospitalization at 3 months. Results: The incidence of the composite endpoint was 26.8% (535/1,996); it was 32.2% (213/662), 25.0% (165/661), and 23.3% (157/673) by chloride tertiles (from the lowest to the highest), respectively. The serum chloride at admission was independently and inversely associated with the composite endpoint risk (hazard ratio: 0.967; 95% confidence interval: 0.939 to 0.996; p = 0.026) in contrast to sodium, which was no longer significant (p > 0.05) after multivariable adjustment. Pearson correlation between serum chloride and sodium was 0.747 (p < 0.001). However, an increased AUC was not observed by adding sodium to model composed of age, sex, NYHA class, diabetes, log BNP and chloride (0.620 vs. 0.612, p = 0.132). Subgroup analysis showed the presence or absence of hyponatremia did not affect the association between chloride and composite endpoint risk. Conclusions: Low serum chloride at admission was associated with poor outcomes in Chinese hospitalized patients with heart failure. These findings warrant future studies for tackling the potential pathophysiological mechanisms and correction methods of hypochloremia in heart failure.

19.
Polymers (Basel) ; 14(7)2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35406313

RESUMEN

Bioinspired composites, capable of tailoring mechanical properties by the strategy of making full use of their advantages and bypassing their drawbacks, are vital for numerous engineering applications such as lightweight ultrahigh-strength, enhanced toughness, improved low-/high- velocity impact resistance, wave filtering, and energy harvesting. Helicoidal composites are examples of them. However, how to optimize the geometric structure to maximize the low-velocity impact resistance of helicoidal composites has been ignored, which is vital to the lightweight and high strength for aerospace, defense, ship, bridge, dam, vessel, and textile industries. Here, we combined experiments and numerical simulations to report the dynamic response of helicoidal composites subjected under low-velocity impact (0-10 m/s). Our helicoidal structures, inspired by the Stomatopod Dactyl club, are fabricated using polylactic acid (PLA) by FFF in a single-phase way. The helicoidal strategy aims to exploit, to a maximum extent, the axial tensile strength of filaments and simultaneously make up the shortage of inter-filament contact strength. We demonstrate experimentally that the low-velocity impact resistance has been enhanced efficiently as the helicoidal angle varies, and that the 15° helicoidal plate is better than others, which has also been confirmed by the numerical simulations. The findings reported here provide a new routine to design composites systems with enhanced impact resistance, offering a method to improve impact performance and expand the application of 3D printing.

20.
Materials (Basel) ; 15(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36143526

RESUMEN

Freeze-thaw cycles (FTCs) and steel bar corrosion (SBC) are the most common service conditions of hydraulic concrete and have significant impacts on its durability. Using pullout and microscopic tests of different FTC and SBC rates, we selected the mass loss rate, ultrasonic velocity, bond strength and bond slip in order to describe the changes in the macro-properties, and also selected the porosity and pore size distribution as micro-parameters in order to explore the influence of FTCs and SBC on the mechanical properties of hydraulic concrete. The results showed that the bond strength decreased as the FTCs increased due to the microstructure damage caused by FTC and SBC, which affects the mechanical properties. A corrosion rate of ≤3% offset the damage caused by 50 FTCs. FTCs and SBC resulted in superimposed damage effects on the concrete. In addition, we established a bond strength damage model based on the joint FTCs and SBC and quantitatively described the degradation law of the macro-mechanical properties. The analysis shows that the influence of FTCs on the bond strength was greater than that of the SBC. These research results can provide a reference and experimental support for the frost-resistant design and durability prediction of hydraulic concrete structures in cold environments.

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