Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Sensors (Basel) ; 24(7)2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38610272

RESUMEN

Coherent Doppler wind lidar (CDWL) uses transmitted laser pulses to measure wind velocity distribution. However, the echo signal of CDWL is easily affected by atmospheric turbulence, which can decrease the signal-to-noise ratio (SNR) of lidar. To improve the SNR, this paper proposes a pulse accumulation method based on the cross-correlation function to estimate the phase of the signal. Compared with incoherent pulse accumulation, the proposed method significantly enhances the correlation between signals from different periods to obtain high SNR gains that arise from pulse accumulation. Using simulation, the study evaluates the effectiveness of this phase estimation method and its robustness against noise in algorithms which analyze Doppler frequency shifts. Furthermore, a CDWL is developed for measuring the speed of an indoor motor turntable and the outdoor atmospheric wind field. The phase estimation method yielded SNR gains of 28.18 dB and 32.03 dB for accumulation numbers of 500 and 1500, respectively. The implementation of this method in motor turntable speed measurements demonstrated a significant reduction in speed error-averaging 9.18% lower than that of incoherent accumulation lidar systems. In experiments that measure atmospheric wind fields, the linear fit curve slope between the measured wind speed and the wind speed measured via a commercial wind-measuring lidar can be reduced from 1.146 to 1.093.

2.
BMC Plant Biol ; 23(1): 243, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37150831

RESUMEN

BACKGROUD: Paeonia holds considerable value in medicinal, ornamental horticultural, and edible oil industries, but the incomplete state of phylogenetic research in this genus poses a challenge to the effective conservation and development of wild germplasm, and also impedes the practical utilization of existing cultivars. Due to its uniparental inheritance and lack of recombination, the plastome (i.e., plastid genome), which is a valuable molecular marker for phylogenetic analyses, is characterized by an appropriate rate of nucleotide evolution. METHODS: In this study, 10 newly assembled data and available reported data were combined to perform a comparative genomics and phylogenetics analysis of 63 plastomes of 16 Paeonia species, primarily from East Asia, which is the origin and diversity center of Paeonia. RESULTS: Ranging between 152,153 and 154,405 bp, most plastomes displayed a conserved structure and relatively low nucleotide diversity, except for six plastomes, which showed obvious IR construction or expansion. A total of 111 genes were annotated in the Paeonia plastomes. Four genes (rpl22, rps3, rps19 and ycf1) showed different copy numbers among accessions while five genes (rpl36, petN, psbI, rpl33 and psbJ) showed strong codon usage biases (ENC < 35). Additional selection analysis revealed that no genes were under positive selection during the domestication of tree peony cultivars whereas four core photosynthesis-related genes (petA, psaA, psaB and rbcL) were under positive selection in herbaceous peony cultivars. This discovery might contribute to the wide adaption of these cultivars. Two types of molecular markers (SSR and SNP) were generated from the 63 plastomes. Even though SSR was more diverse than SNP, it had a weaker ability to delimit Paeonia species than SNP. The reconstruction of a phylogenetic backbone of Paeonia in East Asia revealed significant genetic divergence within the P. ostii groups. Evidence also indicated that the majority of P. suffruticosa cultivars had a maternal origin, from P. ostii. The results of this research also suggest that P. delavayi var. lutea, which likely resulted from hybridization with P. ludlowii, should be classified as a lineage within the broader P. delavayi group. CONCLUSIONS: Overall, this study's research findings suggest that the Paeonia plastome is highly informative for phylogenetic and comparative genomic analyses, and could be useful in future research related to taxonomy, evolution, and domestication.


Asunto(s)
Paeonia , Filogenia , Paeonia/genética , Domesticación , Asia Oriental , Nucleótidos
3.
Opt Express ; 31(26): 44693-44702, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38178533

RESUMEN

We experimentally demonstrated a one-to-two-point free-space optical communication (FSO) system based on non-mechanical beam servo device in the laboratory. After the initial pointing, two sets of liquid crystal variable retarder cascaded polarization gratings perform non-mechanical beam servo and realized switching or working simultaneously of two communication links. The non-mechanical beam steerer had four diffraction fields; each can achieve beam steering with a 3.72° field and 30.77 µrad resolution, and the system emission efficiency was higher than 77%. The corresponding switching times of links at 2, 4, and 10 Hz were 46.7, 43.8, and 42.1 ms, respectively. In the quasistatic condition, the sensitivities of the two links under the data rate of 10.3125 Gbps were -23.18 and -23.01 dBm, respectively, indicating the service transmission capability of the multi-node beam control system.

4.
Opt Express ; 31(2): 3199-3211, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36785317

RESUMEN

Optical Phase Arrays (OPAs) are expected to be an ideal solution to achieve beam shaping, laser radar (LIDAR), free-space optical communications, and spatially resolved optical sensors, etc. We demonstrated a low-power consumption 32-channel OPA with non-uniformly spaced waveguides based on InP substrate. The phase shifters are based on a p-i-n structure which are operated with reverse bias and have a low power consumption. Besides, in order to improve the performance especially to obtain larger steering angle and narrower beam divergence without increasing the number of channels, we have optimized the spacing between the output waveguides. The fabricated OPA achieved a steering angle of 35° with the side lobe suppression ratio more than 8.2 dB across the angle range from -20° to 20° in the far field, which is the largest phase tuning steering angle reported by InP-based OPAs as far as we know. The divergence angle is about 0.46° in the phase steering dimension and the power consumption of the OPA at each steering angle is lower than 7.5 mW.

5.
Opt Express ; 30(19): 33465-33478, 2022 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-36242382

RESUMEN

This study proposes a method to reduce link loss in near-ground space laser communication with fiber-nutation-based mutual coupling. We designed a transmit-receive coaxial laser terminal with a 50 mm aperture and implemented beam acquisition tracking and nutation coupling using a single-detector and single-actuator. Following an indoor experiment and a 1 km field test, the single-ended nutation coupling and the two-way nutation mutual coupling theories were compared and analyzed. In conclusion, the proposed method could significantly increase the reception efficiency by ∼8 dB. The bit error rate of 10 Gbps pseudo-random code transmission was 2.478E-9. We also demonstrated video transmission.

6.
Breed Sci ; 72(4): 275-284, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36699823

RESUMEN

The induction of 2n pollen is an important technique for breeding polyploid plants. Here, we observed meiosis in the pollen mother cells (PMCs) of six Phalaenopsis cultivars and attempted to induce 2n pollen. The meiotic stage was related to flower bud length. During meiosis, Phalaenopsis cultivars with flower widths of approximately 20-40 mm and 50-60 mm had bud lengths of approximately 3-8 mm and 5-13 mm, respectively. The duration of meiosis ranged from 4.2 to 14 d. This was the first study to characterize meiosis of the PMCs of Phalaenopsis. The natural generation frequency of 2n pollen varied from 0.68% to 1.78%. Meiotic stage and colchicine concentration significantly affected the induction of 2n pollen. The most effective treatment for obtaining 2n pollen was 0.05% colchicine in the leptotene to zygotene stage for 3 d, which achieved a 2n pollen frequency of 10.04%.

7.
Opt Lett ; 46(9): 2156-2159, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33929442

RESUMEN

We experimentally demonstrated a long-range, large-capacity-featured, airship-based, free-space optical transmission system by using key technologies, such as GPS/INS real-time precision laser pointing, coarse and fine compound high-bandwidth laser tracking, avalanche photodiode detector adaptive control turbulence channel compensation, and the aurora laser fifth-generation (5G) interface protocol, to solve the problems of laser tracking and targeting based on an airship motion platform, high-speed signal transmission under atmospheric channel perturbation, and interface protocol between a wireless laser link and 5G base station signal, respectively. To the best of our knowledge, the first FSO transmission of 5G base station signals between airship platforms with a rate of 2.5 Gbps and a distance of 12 km was realized, and channel turbulence jitter was also recorded for laser links of different altitudes, from 200 to 1000 m, which provides technical and data support for the application of wireless laser links in 5G floating base stations.

8.
Ecotoxicol Environ Saf ; 216: 112177, 2021 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-33839484

RESUMEN

Dietary copper and zinc additives facilitate the growth and development of animals, but heavy metal in feces threatens the ecological environment, and balance is the key to solving the problem. In this study, a trial of 2000 pigs (early nursery, 9-15 kg; late nursery, 15-25 kg; grower: 25-60 kg) was conducted to analyze the effects of different diets (gradient dosage of copper and zinc additives) on growth performance, antioxidant performance, immune function, and fecal heavy metal excretion of piglets and growing pigs. Although no significant differences were observed in average daily gain (ADG) and average daily feed intake (ADFI) between treatments during the entire nursery-grower period, the addition of appropriate high doses of copper and zinc to the diet had a beneficial effect on the antioxidant status and immune function of weaned piglets. Especially at early nursery, compared with the low-copper group (5 mg/kg Cu), the high-copper group (120 mg/kg Cu) could significantly increase the peroxidase (POD), glutathione peroxidase (GSH-PX), total antioxidant capacity (T-AOC), catalase (CAT) and copper/zinc superoxide dismutase (Cu/Zn-SOD), cortisol in the serum. Moreover, the addition of zinc and copper in the diet not only increased the concentration of corresponding trace elements in the serum, but also affected the concentration of other trace elements in the serum. The reduction of copper and zinc content in the diet contributed to reducing the copper and zinc content in feces. In conclusion, we have formulated the mutual benefit dosages of copper and zinc (9-15 kg: 5 mg/kg Cu and 50 mg/kg Zn; 15-25 kg: 4 mg/kg Cu and 50 mg/kg Zn; 25-60 kg: 4 mg/kg Cu and 10 mg/kg Zn) for weaning piglets and growing pigs, which would help ensure the healthy growth of animals and reduce environmental heavy metal residues. CAPSULE: This study developed a mutually beneficial dose of copper and zinc in pig diets, which promotes animal growth and protects the environment.

9.
Chem Biodivers ; 18(2): e2000848, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33403807

RESUMEN

Paeonia cultivars are famous ornamental plants, and some of them are also traditional Chinese medicinal resources. Intersubgeneric hybrids of Paeonia (IHPs) are formed by the hybridization of herbaceous peony (Paeonia lactiflora) and tree peony (Paeonia×suffruticosa or lutea hybrid tree peony). The phenotypic characteristics of IHPs are similar to those of herbaceous peony, and their root systems are large and vigorous. However, their medicinal value has not been reported yet. In this study, the roots of eight IHP samples were analyzed by high performance liquid chromatography quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS/MS). A total of 18 compounds were identified, including phenols, paeonols, monoterpene glycosides, and tannins. The contents of monoterpene glycosides and tannins in IHPs were higher than herbaceous peony and tree peony, exceeding 44.76 mg/g DW and 11.50 mg/g DW, respectively. Three IHPs, 'Prairie Charm', 'Garden Treasure', and 'Yellow Emperor', with more types and a higher content of medicinal compounds, were screened out by cluster analysis. These IHPs have considerable potential for the development of medicinal resources.


Asunto(s)
Paeonia/química , Raíces de Plantas/química , Acetofenonas/análisis , Glicósidos/análisis , Monoterpenos/análisis , Fenoles/análisis , Taninos/análisis
10.
J Anim Physiol Anim Nutr (Berl) ; 105(4): 668-677, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33683742

RESUMEN

Iron is one of the essential trace elements, which is often supplemented as an additive to meet the growing needs of toddlers and young animals. Recommended nutrient intake (RNI) and tolerable upper intake levels (UL) are always set when the iron is supplemented. The purpose of this study was to evaluate the subacute (28 days) toxicity of UL iron to weaned piglet liver. Thirty 23-day-old weaned piglets were divided into three groups and, respectively, supplemented with 100, 300 or 3000 (UL) mg/kg iron. UL iron caused significant weight loss in 4th week (p < 0.05). Divalent metal transporter 1(DMT1) decreased significantly, ferroportin 1 and ferritin increased significantly in the liver of UL iron group (p < 0.05). Although there was no significant effect on liver morphology, UL iron significantly increased hepatic iron, reactive oxygen species (ROS), malondialdehyde (MDA) and protein carbonyl (p < 0.05). UL iron significantly reduced glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT) and total anti-oxidation capacity (T-AOC) in the liver (p < 0.05). Nuclear factor erythroid 2-related factor 2 (Nrf2) activated subunits of glutamate cysteine ligase (Gclc) and glutathione S-transferase A1 (Gsta1) upregulation in the UL iron group liver, thereby increasing resistance to oxidative stress. In conclusion, UL iron supplementation altered iron metabolism, generated free radicals, reduced antioxidant enzyme activity and activated Nrf2 signalling pathway in the weaned piglet liver.


Asunto(s)
Antioxidantes , Hierro , Animales , Antioxidantes/metabolismo , Hígado/metabolismo , Malondialdehído/metabolismo , Estrés Oxidativo , Porcinos , Destete
11.
J Nutr ; 150(4): 704-711, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32060554

RESUMEN

BACKGROUND: The association between high selenium (Se) intake and metabolic disorders such as type 2 diabetes has raised great concern, but the underlying mechanism remains unclear. OBJECTIVE: Through targeted metabolomics analysis, we examined the liver sugar and acylcarnitine metabolism responses to supranutritional selenomethionine (SeMet) supplementation in pigs. METHODS: Thirty-six castrated male pigs (Duroc-Landrace-Yorkshire, 62.0 ± 3.3 kg) were fed SeMet adequate (Se-A, 0.25 mg Se/kg) or SeMet supranutritional (Se-S, 2.5 mg Se/kg) diets for 60 d. The Se concentration, biochemical, gene expression, enzyme activity, and energy-targeted metabolite profiles were analyzed. RESULTS: The Se-S group had greater fasting serum concentrations of glucose (1.9-fold), insulin (1.4-fold), and free fatty acids (FFAs,1.3-fold) relative to the Se-A group (P < 0.05). The liver total Se concentration was 4.2-fold that of the Se-A group in the Se-S group (P < 0.05), but expression of most selenoprotein genes and selenoenzyme activity did not differ between the 2 groups. Seven of 27 targeted sugar metabolites and 4 of 21 acylcarnitine metabolites significantly changed in response to high SeMet (P < 0.05). High SeMet supplementation significantly upregulated phosphoenolpyruvate carboxy kinase (PEPCK) activity by 64.4% and decreased hexokinase and succinate dehydrogenase (SDH) activity by 46.5-56.7% (P < 0.05). The relative contents of glucose, dihydroxyacetone phosphate, α-ketoglutarate, fumarate, malate, erythrose-4-phosphate, and sedoheptulose-7-phosphate in the Se-S group were 21.1-360% greater than those in the Se-A group (P < 0.05). The expression of fatty acid synthase (FASN) and the relative contents of carnitine, hexanoyl-carnitine, decanoyl-carnitine, and tetradecanoyl-carnitine in the Se-S group were 35-97% higher than those in the Se-A group (P < 0.05). CONCLUSIONS: Dietary high SeMet-induced hyperglycemia and hyperinsulinemia were associated with suppression of sugar metabolism and elevation of lipid synthesis in pig livers. Our research provides novel insights into high SeMet intake-induced type 2 diabetes.


Asunto(s)
Carnitina/análogos & derivados , Dieta , Hígado/metabolismo , Selenometionina/administración & dosificación , Azúcares/metabolismo , Animales , Carnitina/metabolismo , Diabetes Mellitus Tipo 2/inducido químicamente , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Homeostasis/efectos de los fármacos , Hiperglucemia/inducido químicamente , Hiperinsulinismo/inducido químicamente , Lípidos/biosíntesis , Hígado/química , Hígado/enzimología , Masculino , Metabolómica/métodos , Modelos Animales , Oxidación-Reducción , ARN Mensajero/análisis , Selenio/administración & dosificación , Selenio/efectos adversos , Selenio/análisis , Selenometionina/efectos adversos , Selenoproteínas/genética , Sus scrofa
12.
BMC Med Imaging ; 20(1): 31, 2020 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-32192440

RESUMEN

BACKGROUND: The aim of this study was to establish a computer-aided automated method for cephalometric superimposition and to evaluate the accuracy of this method based on free-hand tracing. METHODS: Twenty-eight pairs of pre-treatment (T1) and post-treatment (T2) cephalograms were selected. Structural superimpositions of the anterior cranial base, maxilla and mandible were independently completed by three operators performing traditional hand tracing methods and by computerized automation using the feature matching algorithm. To quantitatively evaluate the differences between the two methods, the hand superimposed patterns were digitized. After automated and hand superimposition of T2 cephalograms to T1 cephalometric templates, landmark distances between paired automated and hand T2 cephalometric landmarks were measured. Differences in hand superimposition among the operators were also calculated. RESULTS: The T2 landmark differences in hand tracing between the operators ranged from 0.61 mm to 1.65 mm for the three types of superimposition. There were no significant differences in accuracy between hand and automated superimposition (p > 0.05). CONCLUSIONS: Computer-aided cephalometric superimposition provides comparably accurate results to those of traditional hand tracing and will provide a powerful tool for academic research.


Asunto(s)
Cefalometría/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos , Humanos
13.
Planta ; 251(1): 23, 2019 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-31784828

RESUMEN

Molecular biology can serve as a tool to solve the limitations of traditional breeding and cultivation techniques related to flower patterns, the improvement of flower color, and the regulation of flowering and stress resistance. These characteristics of molecular biology ensured its significant role in improving the efficiency of breeding and germplasm amelioration of Paeonia. This review describes the advances in molecular biology of Paeonia, including: (1) the application of molecular markers; (2) genomics, transcriptomics, proteomics, metabolomics, and microRNA studies; (3) studies of functional genes; and (4) molecular biology techniques. This review also points out select limitations in current molecular biology, analyzes the direction of Paeonia molecular biology research, and provides advice for future research objectives.


Asunto(s)
Paeonia/genética , Flores/genética , Marcadores Genéticos , Variación Genética , Genómica , Biología Molecular
14.
Int J Mol Sci ; 20(15)2019 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-31382697

RESUMEN

Polyether-ether-ketone (peek) is one of the most common materials used for load-bearing orthopedic devices owing to its radiolucency and favorable mechanical properties. However, current smooth-surfaced peek implants can lead to fibrous capsule formation. To overcome this issue, here, peek specimens with well-defined internal cross-linked structures (macropore diameters of 1.0-2.0 mm) were fabricated using a three-dimensional (3D) printer, and an acid-etched microporous surface was achieved using injection-molding technology. The cell adhesion properties of smooth and microporous peek specimens was compared in vitro through a scanning electron microscope (SEM), and the soft tissue responses to the both microporous and cross-linked structure of different groups were determined in vivo using a New Zealand white rabbit model, and examined through histologic staining and separating test. The results showed that the acid-etched microporous surface promoted human skin fibroblasts (HSF) adherence, while internal cross-linked structure improved the ability of the peek specimen to form a mechanical combination with soft tissue, especially with the 1.5 mm porous specimen. The peek specimens with both the internal cross-linked structure and external acid-etched microporous surface could effectively promote the close integration of soft tissue and prevent formation of fibrous capsules, demonstrating the potential for clinical application in surgical repair.


Asunto(s)
Materiales Biocompatibles/farmacología , Adhesión Celular/efectos de los fármacos , Impresión Tridimensional , Prótesis e Implantes/efectos adversos , Animales , Materiales Biocompatibles/química , Éter/química , Éter/farmacología , Humanos , Cetonas/química , Cetonas/farmacología , Polietilenglicoles/química , Porosidad , Conejos , Propiedades de Superficie
15.
J Prosthet Dent ; 121(3): 531-534, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30509547

RESUMEN

For a patient with a unilateral orbital defect, an esthetic orbital prosthesis plays an essential role in enhancing quality of life. This technique describes the combined use of a facial scanner and an intraoral scanner to acquire the digital scan for the design and fabrication of an orbital prosthesis. The method results in an esthetic prosthesis with accurate skin texture reproduction.


Asunto(s)
Implantes Orbitales , Calidad de Vida , Diseño Asistido por Computadora , Estética Dental , Cara , Humanos
16.
Biochem Biophys Res Commun ; 503(1): 297-303, 2018 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-29890135

RESUMEN

Iron overload causes many diseases, while the underlying etiologies of these diseases are unclear. Cell death processes including apoptosis, necroptosis, cyclophilin D-(CypD)-dependent necrosis and a recently described additional form of regulated cell death called ferroptosis, are dependent on iron or iron-dependent reactive oxygen species (ROS). However, whether the accumulation of intracellular iron itself induces ferroptosis or other forms of cell death is largely elusive. In present study, we study the role of intracellular iron overload itself-induced cell death mechanisms by using ferric ammonium citrate (FAC) and a membrane-permeable Ferric 8-hydroxyquinoline complex (Fe-8HQ) respectively. We show that FAC-induced intracellular iron overload causes ferroptosis. We also identify 3-phosphoinositide-dependent kinase 1 (PDK1) inhibitor GSK2334470 as a potent ferroptosis inhibitor. Whereas, Fe-8HQ-induced intracellular iron overload causes unregulated necrosis, but partially activates PARP-1 dependent parthanatos. Interestingly, we identify many phenolic compounds as potent inhibitors of Fe-8HQ-induced cell death. In conclusion, intracellular iron overload-induced cell death form might be dependent on the intracellular iron accumulation rate, newly identified cell death inhibitors in our study that target ferroptosis and unregulated oxidative cell death represent potential therapeutic strategies against iron overload related diseases.


Asunto(s)
Proteínas Quinasas Dependientes de 3-Fosfoinosítido/antagonistas & inhibidores , Muerte Celular/efectos de los fármacos , Indazoles/farmacología , Sobrecarga de Hierro/tratamiento farmacológico , Sobrecarga de Hierro/patología , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/metabolismo , Descubrimiento de Drogas , Compuestos Férricos/metabolismo , Células HeLa , Humanos , Hidroxiquinolinas/metabolismo , Hierro/metabolismo , Sobrecarga de Hierro/metabolismo , Especies Reactivas de Oxígeno/metabolismo
17.
Appl Opt ; 56(19): 5342-5348, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29047487

RESUMEN

The inter-satellite laser link is the backbone of the next inter-satellite information network, and ranging and communication are the main functions of the inter-satellite laser link. This study focuses on the inter-satellite laser ranging based on the pseudo-code correlation technology. In this paper, several typical laser-ranging methods have been compared and we determined that the laser pseudo-code ranging architecture is more suitable for the inter-satellite laser communication link. The pseudo-code ranging system is easy to combine with a digital communication system, and we used it to calculate integer ambiguity by modulating the time information. The main challenge of the ranging system is range precision, which is the main focus of this paper. First, the framework of the pseudo-code ranging system is introduced; the ranging architecture of dual one-way ranging is used to eliminate the clock error between the two transceivers, and then the uncertainty of the phase detector is analyzed. In the analysis, the carrier to noise ratio and the ranging code rate are constrained by the laser communication link margin and the electronic hardware limitation. Therefore, the relationship between the sampling depth and the phase detector uncertainty is verified. A series of optical fiber channel laser pseudo-code ranging experiments demonstrated the effects of sampling depth on the ranging precision. By adjusting the depth of storage, such as the depth of 1.6 Mb, we obtained a pseudo-range measurement precision of 0.33 mm (1σ), which is equivalent to 0.0001 times code subdivision of 10.23 Mcps pseudo-code. This paper has achieved high precision in a pseudo-range measurements, which is the foundation of the inter-satellite laser link.

18.
Antimicrob Agents Chemother ; 60(7): 4364-8, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27114282

RESUMEN

This study reports the increasing prevalence of clinical Escherichia coli of sequence type 167 (ST167) carrying both blaNDM-1 and blaNDM-5 on the conjugative IncX3 plasmid in various parts of China. Close surveillance is needed to monitor the future dissemination of ST167 strains that harbor blaNDM-5 or other blaNDM-like genes.


Asunto(s)
Antibacterianos/farmacología , Carbapenémicos/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , China , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Pruebas de Sensibilidad Microbiana , beta-Lactamasas
19.
J Craniofac Surg ; 27(2): 405-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26872281

RESUMEN

Sixty-nine experienced Chinese orthodontists evaluated 108 Chinese patients' facial attractiveness from set of photographs (frontal, lateral, and frontal smiling photos) taken at the end of orthodontic treatment. These 108 patients, which contained an equal number of patients with Class I, II, and III malocclusion, were randomly selected from 6 orthodontic treatment centers throughout China. Spearman rank-order correlation coefficients (rs) analyses were performed to examine agreement in ranking between all judge pairs. Pearson correlation and multivariate regression were performed to examine the correlation between cephalometric measures and end-of-treatment Photo Attractiveness Rank.96.68% judge pairs showed moderate correlated (+0.4 ≤ rs < +0.7) subjective rankings. Cephalometric measures significantly correlated with end-of-treatment Photo Attractiveness Rank included interincisal angle (r = 0.330, P < 0.05), L1/MP° (r = 0.386, P < 0.05), L1-NBmm (r = 0.451, P < 0.01), L1/NB° (r = 0.374, P < 0.05), and profile angle (r = 0.353, P < 0.05) in Class I patients with an explained variance of 32.8%, and ANB angle (r = 0.432, P < 0.01), angle of convexity (r = 0.448, P < 0.01), profile angle (r = 0.488, P < 0.01), Li to E-line (r = 0.374, P < 0.05), Li to B-line (r = 0.543, P < 0.01), and Z angle (r = 0.543, P < 0.01) in Class II patient with an explained variance of 43.3%.There was less association than expected between objective measurements on the lateral cephalograms and clinicians' rankings of facial attractiveness on clinical photography in Chinese patients. Straight-stand lower incisor was desired for facial attractiveness of Class I malocclusion; and sagittal relationship and lip prominence influence the esthetics of Class II malocclusion in Chinese population.


Asunto(s)
Cefalometría/métodos , Estética Dental , Cara/anatomía & histología , Maloclusión/terapia , Adolescente , Adulto , Niño , China , Femenino , Humanos , Masculino , Maloclusión/diagnóstico , Sonrisa , Adulto Joven
20.
AIDS Behav ; 19(1): 50-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24879629

RESUMEN

Human immunodeficiency virus (HIV) carries a high level of stigma to the HIV-infected individuals and their family members. Children of HIV-infected parents in China are particularly affected. The present study examined the relationship between associative stigma, self-esteem, optimism, anxiety and depression among 195 children of HIV-infected parents in rural China. Findings showed that more than one-third (35.4 %) of the participants scored higher than cut-off for depression; and 23.6-67.7 % of them scored higher than cut-off for different types of anxiety disorders. Structural equation modelling revealed that associative stigma had a significant negative relationship on self-esteem and optimism, which were associated with higher levels of depression and anxiety. The indirect effects of associative stigma on depression and anxiety were significant. The overall model showed a satisfactory fit. Findings suggest that associative stigma has a significant negative impact on mental health of children affected by HIV. Interventions to reduce their associative stigma are warranted.


Asunto(s)
Ansiedad/epidemiología , Hijo de Padres Discapacitados/psicología , Depresión/epidemiología , Infecciones por VIH/psicología , Estigma Social , Adolescente , Niño , Hijo de Padres Discapacitados/estadística & datos numéricos , Niños Huérfanos/psicología , China/epidemiología , Estudios Transversales , Femenino , Infecciones por VIH/epidemiología , Humanos , Resiliencia Psicológica , Factores de Riesgo , Población Rural , Autoimagen , Apoyo Social , Encuestas y Cuestionarios
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA