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1.
Proc Natl Acad Sci U S A ; 121(25): e2406788121, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38865267

RESUMEN

Heritable symbionts are common among animals in nature, but the molecular mechanisms underpinning symbiont invasions of host populations have been elusive. In this study, we demonstrate the spread of Rickettsia in an invasive agricultural pest, the whitefly Bemisia tabaci Mediterranean (MED), across northeastern China from 2018 to 2023. Here, we show that the beneficial symbiont Rickettsia spreads by manipulating host hormone signals. Our analyses suggest that Rickettsia have been horizontally acquired by B. tabaci MED from another invasive whitefly B. tabaci Middle East-Asia Minor 1 during periods of coexistence. Rickettsia is transmitted maternally and horizontally from female B. tabaci MED individuals. Rickettsia infection enhances fecundity and results in female bias among whiteflies. Our findings reveal that Rickettsia infection stimulates juvenile hormone (JH) synthesis, in turn enhancing fecundity, copulation events, and the female ratio of the offspring. Consequently, Rickettsia infection results in increased whitefly fecundity and female bias by modulating the JH pathway. More female progeny facilitates the transmission of Rickettsia. This study illustrates that the spread of Rickettsia among invasive whiteflies in northeastern China is propelled by host hormone regulation. Such symbiont invasions lead to rapid physiological and molecular evolution in the host, influencing the biology and ecology of an invasive species.


Asunto(s)
Fertilidad , Hemípteros , Rickettsia , Razón de Masculinidad , Simbiosis , Animales , Rickettsia/fisiología , Hemípteros/microbiología , Hemípteros/fisiología , Femenino , Masculino , Hormonas Juveniles/metabolismo , China
2.
Sensors (Basel) ; 24(12)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38931764

RESUMEN

The quality of aerial remote sensing imaging is heavily impacted by the thermal distortions in optical cameras caused by temperature fluctuations. This paper introduces a lumped parameter thermal network (LPTN) model for the optical system of aerial cameras, aiming to serve as a guideline for their thermal design. By optimizing the thermal resistances associated with convection and radiation while considering the camera's unique internal architecture, this model endeavors to improve the accuracy of temperature predictions. Additionally, the proposed LPTN framework enables the establishment of a heat leakage network, which offers a detailed examination of heat leakage paths and rates. This analysis offers valuable insights into the thermal performance of the camera, thereby guiding the refinement of heating zones and the development of effective active control strategies. Operating at a total power consumption of 26 W, the thermal system adheres to the low-power limit. Experimental data from thermal tests indicate that the temperatures within the optical system are maintained consistently between 19 °C and 22 °C throughout the flight, with temperature gradients remaining below 3 °C, satisfying the temperature requirements. The proposed LPTN model exhibits swiftness and efficacy in determining thermal characteristics, significantly facilitating the thermal design process and ensuring optimal power allocation for aerial cameras.

3.
Chin J Traumatol ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39147675

RESUMEN

Traumatic aortic injury (TAI) is an acute, critical, and severe disease, and then combined with multiple organ damage, it is even more dangerous. TAI progresses very rapidly, with a pre-hospital mortality rate of 57% - 80%, and even when arriving at the hospital, more than one-third of the patients die within 4 h, and it is the 2nd leading cause of death in individuals aged 4 - 34 years. In addition, the incidence of TAI combined with injury was 81.4%. Therefore, early diagnosis, expeditious surgery, and timely and effective multidisciplinary cooperation are essential for successful rescue. The authors report 2 patients with acute traumatic aortic dissection combined with multiple organ injuries and treated with emergency endovascular surgery to discuss their clinical characteristics and treatment experience, and to provide experience in the diagnosis and treatment of such patients.

4.
Gen Physiol Biophys ; 42(5): 431-442, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37702448

RESUMEN

This study aimed to examine the clinical and prognostic significance of cell-cycle progression gene 1 (CCPG1) in hepatocellular carcinoma (HCC). We firstly analyzed CCPG1 expression in various cancers using The Cancer Genome Atlas and the Genotype-Tissue Expression project databases. The relative expression levels of CCPG1 were determined in 164 paired HCC and adjacent tissues using immunohistochemistry. The correlation between CCPG1 and clinicopathological characteristics of HCC was analyzed. Cox proportional models were used to identify the prognostic factors for overall survival (OS) and disease-free survival (DFS). The expression of CCPG1 was lower in HCC tissues than in adjacent non-tumor liver tissues. The expression of CCPG1 was significantly correlated with tumor number (p = 0.02) and tumor differentiation (p = 0.04) in HCC. Lower expression of CCPG1 in HCC patients was associated with poor OS and DFS (p < 0.01). Relative low expression of CCPG1 in HCC is significantly correlated with the poor prognosis of HCC patients after surgical resection, suggesting its possible role as a potential prognostic marker for HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Diferenciación Celular , Neoplasias Hepáticas/diagnóstico , Pronóstico
5.
Mol Ecol ; 31(9): 2611-2624, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35243711

RESUMEN

Horizontally transferred genes (HTGs) play a key role in animal symbiosis, and some horizontally transferred genes or proteins are highly expressed in specialized host cells (bacteriocytes). However, it is not clear how HTGs are regulated, but microRNAs (miRNAs) are prime candidates given their previously demonstrated roles in symbiosis and impacts on the expression of host genes. A horizontally acquired PanBC that is highly expressed in whitefly bacteriocytes can cooperate with an obligate symbiont Portiera for pantothenate production, facilitating whitefly performance and Portiera titre. Here, we found that a whitefly miRNA, novel-m0780-5p, was up-regulated and its target panBC was down-regulated in Portiera-eliminated whiteflies. This miRNA was located in the cytoplasmic region of whitefly bacteriocytes. Injection of novel-m0780-5p agomir reduced the expression of PanBC in whitefly bacteriocytes, while injection of novel-m0780-5p antagomir enhanced PanBC expression. Agomir injection also reduced the pantothenate level, Portiera titre and whitefly performance. Supplementation with pantothenate restored Portiera titre and the fitness of agomir-injected whiteflies. Thus, we demonstrate that a whitefly miRNA regulates panBC-mediated host-symbiont collaboration required for pantothenate synthesis, benefiting the whitefly-Portiera symbiosis. Both panBC and novel-m0780-5p are present in the genomes of six Bemisia tabaci species. The expression of a novel miRNA in multiple B. tabaci species suggests that the miRNA evolved after panBC acquisition, and allowed this gene to be more tightly regulated. Our discovery provides the first account of a HTG being regulated by a miRNA from the host genome, and suggests key roles for interactions between miRNAs and HTGs in the functioning of symbiosis.


Asunto(s)
Halomonadaceae , Hemípteros , MicroARNs , Animales , Halomonadaceae/genética , Hemípteros/genética , MicroARNs/genética , Simbiosis/genética
6.
Exp Cell Res ; 399(1): 112453, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33358859

RESUMEN

RNA-binding proteins (RBPs) closely regulate the whole lifecycle of most RNA molecules, from the very early stage of transcription to RNA decay. Dysregulation of RBPs significantly affects the fate of cancer-related transcripts. Therefore, it is imperative to fully understand the complicated RBP-RNA regulatory networks in malignant diseases and to explore novel therapeutic targets. The RBP DAZAP1 (deleted in azoospermia-associated protein 1), originally identified as an important protein in spermatogenesis, had rarely been studied in the context of carcinogenesis. The role of DAZAP1 in hepatocellular carcinoma (HCC) was unveiled in this study. The relative expression of DAZAP1 was significantly upregulated in HCC and was positively associated with several key malignant characteristics and poor postoperative survival in patients. DAZAP1 knockdown by small interfering RNA markedly inhibited HCC cell proliferation, migration and invasion. Furthermore, DAZAP1 significantly reduced cellular sensitivity to sorafenib (SF), which had been proven to be an inducer of ferroptosis by targeting the system Xc- (composed of a light chain, xCT/SLC7A11, and a heavy chain, 4F2 heavy chain). At the mechanistic level, DAZAP1 was identified as a potent inhibitor of ferroptosis and an efficient binding partner of SLC7A11 mRNA. Further study revealed that DAZAP1 interacted with the 3'UTR (untranslated region) of SLC7A11 mRNA and positively regulated its stability. In our work, we clarified novel functions of DAZAP1 and preliminarily revealed its underlying mechanism in ferroptosis, which may be conducive to the exploration of biomarkers and therapeutic targets in HCC patients.


Asunto(s)
Sistema de Transporte de Aminoácidos y+/metabolismo , Carcinoma Hepatocelular/patología , Ferroptosis/genética , Neoplasias Hepáticas/patología , Proteínas de Unión al ARN/fisiología , Sistema de Transporte de Aminoácidos y+/genética , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Progresión de la Enfermedad , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Metástasis de la Neoplasia , Unión Proteica , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo
7.
Chin J Physiol ; 64(3): 135-141, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34169919

RESUMEN

Acute kidney injury (AKI) in community-acquired septic patients is often associated with relatively high mortality rate. However, the appropriate timing for continuous renal replacement therapy (CRRT) initiation remains controversial. In the present study, we retrospectively analyzed 123 community-acquired septic patients with AKI admitted to the medical intensive care unit (ICU). The baseline patient characteristics and renal function parameters were compared between survivors and non-survivors. Then, we used the Cox proportional hazard analysis to identify the risk factors for ICU mortality. Moreover, we employed the area under the receiver operating characteristic curve analysis to determine the cutoff time for CRRT initiation. Finally, we used the cutoff time to separate the patients into early (treatment initiated earlier than the cutoff time) and late (treatment initiated later than the cutoff time) CRRT groups and performed the Kaplan-Meier survival analysis to assess the overall mortalities. At the time of ICU release, the mortality rate of the 123 patients was 48.8% (n = 60). We identified several baseline characteristics and renal function parameters that were significantly different between the survivors and the non-survivors. All of them were also identified as the risk factors for community-acquired sepsis. Importantly, the cutoff time point to distinguish the early and late CRRT initiation groups was determined to be 16 h after AKI onset. Based on such grouping, the mortality rate was significantly lower in the early CRRT initiation group at 30, 60 and 90 days. Our data suggest that initiating CRRT within 16 h may help improve the mortality rate of community-acquired septic patients.


Asunto(s)
Lesión Renal Aguda , Terapia de Reemplazo Renal Continuo , Sepsis , Lesión Renal Aguda/terapia , Humanos , Terapia de Reemplazo Renal , Estudios Retrospectivos , Sepsis/terapia
8.
J Cell Physiol ; 235(10): 6929-6941, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32003018

RESUMEN

In recent years, an increasing number of circular RNAs (circRNAs) have been discovered in hepatocellular carcinoma (HCC). However, the functions of most circRNAs require further investigation. Here, we found that circBACH1 was significantly upregulated in HCC tissues and that high circBACH1 levels were closely associated with poor prognosis. In addition, circBACH1 could promote HCC growth by accelerating cell cycle progression in vitro and in vivo. We next investigated the cellular and molecular mechanisms and discovered that circBACH1 inhibited p27 translation, which influenced cell cycle progression. Moreover, we revealed that circBACH1 could combine directly with HuR using RNA immunoprecipitation assays, pull-down assays, and electrophoretic mobility shift assays. The combination of these molecules facilitated HuR translocation from the nucleus to the cytoplasm according to the fluorescence in situ hybridization and immunofluorescence results. Finally, silencing HuR abrogated circBACH1's inhibition of p27 translation and abolished the circBACH1-induced effect on HCC proliferation. In sum, circBACH1 plays a significant role as an oncogene through the circBACH1/HuR/p27 axis in HCC development.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Carcinoma Hepatocelular/genética , Proliferación Celular/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Proteína 1 Similar a ELAV/genética , Neoplasias Hepáticas/genética , ARN Circular/genética , Animales , Carcinoma Hepatocelular/patología , Ciclo Celular/genética , Línea Celular , Línea Celular Tumoral , Citoplasma/genética , Células Hep G2 , Humanos , Hibridación Fluorescente in Situ/métodos , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Desnudos , Regulación hacia Arriba/genética
9.
Opt Express ; 28(15): 21766-21782, 2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32752449

RESUMEN

The ultra-field infrared and visible image registration is a challenging task due to its nonlinear imaging and multi-modal image features. In this paper, a robust registration method is proposed for the ultra-field infrared and visible images. First, control points are extracted utilizing phase congruency and optimized based on the guidance map, which is proposed according to significant structures information. Second, ROI pair matching is accomplished based on epipolar curve. Its effect is equivalent to a search window that is popular in methods with the standard field of view, and it can overcome the content differences in the search window caused by nonlinear imaging and vision disparity. Third, a descriptor, named multiple phase congruency directional pattern (MPCDP), is established and composed of distribution information and main direction. The phase congruency amplitudes are encoded as binary patterns, and then they are represented as weighted histogram for distribution information. Six pairs of ultra-field infrared and visible images are employed for registration experiments, and the results demonstrate that the performance of the proposed is robust and accurate in five types of ultra-field scenes and two different camera relationships.

10.
Inorg Chem ; 59(10): 6942-6952, 2020 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-32379962

RESUMEN

In this work, for the first time, we fabricated a novel covalent organic framework (COF)-based 2D-2D heterojunction composite MoS2/COF by a facile hydrothermal method. The results of photocatalytic degradation of TC and RhB under simulated solar light irradiation showed that the as-prepared composite exhibited outstanding catalytic efficiency compared with pristine COFs and MoS2. The significantly enhanced catalytic efficiency can be ascribed to the formation of 2D-2D heterojunction with a well-matched band position between COF and MoS2, which can effectively restrain the recombination of charge carriers and increase the light absorption as well as the specific surface area. Moreover, the fabricated 2D-2D layered structure can effectively increase the contact area with an intimate interface contact, which greatly facilitates the charge mobility and transfer in the interfaces. This study reveals that artful integration of organic (COFs) and inorganic materials into a single hybrid with a 2D-2D interface is an effective strategy to fabricate highly efficient photocatalysts.

11.
Inorg Chem ; 59(10): 7027-7038, 2020 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-32348121

RESUMEN

In the present study, a hierarchical Co9S8@ZnAgInS heterostructural cage was developed for the first time which can photocatalytically produce hydrogen and degrade organic pollutants with high efficiency. First, the Co9S8 dodecahedron was synthesized using a metal-organic framework (MOFs) material, ZIF-67, as a precursor, then two kinds of metal sulfide semiconductors were elaborately integrated into a hierarchical hollow heterostructural cage with coupled heterogeneous shells and 2D nanosheet subunits. The artfully designed hollow heterostructural composite exhibited remarkable photocatalytic activity without using any cocatalysts, with a 9395.3 µmol g-1 h-1 H2 evolution rate and high degradation efficiency for RhB. The significantly enhanced photocatalytic activity can be attributed to the unique architecture and intimate-contact interface between Co9S8 and ZnAgInS, which promote the transfer and separation of the photogenerated charges, increase light absorption, and offer large surface area and active sites. This work presents a new strategy to design highly active semiconductor photocatalysts by using MOF materials as precursors and coupling of metal sulfide semiconductors to form hollow architecture dodecahedron cages with an intimate interface.

12.
Appl Opt ; 58(4): 744-751, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30874115

RESUMEN

A method is proposed to calibrate the long-wave infrared ultra-wide-angle camera in this paper. In addition, a novel calibration chessboard is designed and an advanced chessboard corner positioning method is adopted to improve the calibration precision. The designed calibration chessboard can achieve high thermal infrared contrast and exhibits outstanding stability, which is made of a thermoelectric semiconductor refrigeration device. The proposed subpixel corner positioning method can accurately locate the corners on the calibration chessboard according to the characteristics of the infrared image and the checkerboard pattern. Both the principle of the proposed infrared chessboard and the subpixel corner positioning procedure were presented, and the calibration experiment showed that the mean reprojection error and the root mean square error were reduced to 0.32 pixel and 0.39 pixel, respectively. Comparison studies were also performed to verify the calibration effect of the proposed method, and the possibilities of camera calibration error of the proposed method were analyzed.

13.
Pestic Biochem Physiol ; 159: 80-84, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31400787

RESUMEN

The plastid acetyl coenzyme carboxylase (ACCase) Trp1999Leu mutation was identified in a Beckmannia syzigachne population resistant to fenoxaprop-p-ethyl. The pattern of cross-resistance for the Trp1999Leu mutation is still ambiguous. In this paper, mutant homozygote (1999Leu/Leu, RR) and wild type (1999Trp/Trp, SS) B. syzigachne plants with the same genetic background were purified from the JS-26 population using the dCAPS method. The activity of ACCase in RR and SS was determined. Then, the cross-resistance pattern to ACCase inhibiting herbicides of the Trp1999Leu mutation was determined using the whole-plant method. ACCase activity showed that the Trp1999Leu mutation decreased ACCase sensitivity to fenoxaprop-p-ethyl by 2.73-fold. A dose-response experiment indicated that the Trp1999Leu mutation conferred high resistance to quizalofop-p-ethyl (20.29-fold), metamifop (12.22-fold) and pinoxaden (18.60-fold), moderate resistance to fenoxaprop-p-ethyl (8.20-fold) and sethoxydim (6.38-fold), low resistance to cyhalofop-butyl (2.73-fold) and no resistance to clodinafop-propargyl (1.42 fold) and clethodim (1.59-fold). This is the first report of the role of Trp1999Leu in fenoxaprop-p-ethyl resistance and of the patterns of cross-resistance to ACCase-inhibiting herbicides in B. syzigachne.


Asunto(s)
Acetil-CoA Carboxilasa/genética , Herbicidas/farmacología , Poaceae/efectos de los fármacos , Poaceae/genética , Anilidas/farmacología , Benzoxazoles/farmacología , Ciclohexanonas/farmacología , Resistencia a los Herbicidas/genética , Compuestos Heterocíclicos con 2 Anillos/farmacología , Mutación/genética , Propionatos/farmacología , Piridinas/farmacología , Quinoxalinas/farmacología
14.
Sensors (Basel) ; 18(5)2018 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-29695041

RESUMEN

The navigation accuracy of the inertial navigation system (INS) can be greatly improved when the inertial measurement unit (IMU) is effectively calibrated and compensated, such as gyro drifts and accelerometer biases. To reduce the requirement for turntable precision in the classical calibration method, a continuous dynamic self-calibration method based on a three-axis rotating frame for the hybrid inertial navigation system is presented. First, by selecting a suitable IMU frame, the error models of accelerometers and gyros are established. Then, by taking the navigation errors during rolling as the observations, the overall twenty-one error parameters of hybrid inertial navigation system (HINS) are identified based on the calculation of the intermediate parameter. The actual experiment verifies that the method can identify all error parameters of HINS and this method has equivalent accuracy to the classical calibration on a high-precision turntable. In addition, this method is rapid, simple and feasible.

16.
Appl Opt ; 56(28): 7803-7807, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29047763

RESUMEN

To solve the problem of poor real-time measurement caused by a hyperspectral imaging system and to simplify the design in passive ranging technology based on oxygen absorption spectrum, a filter-based non-imaging ranging method is proposed. In this method, three bandpass filters are used to obtain the source radiation intensities that are located in the oxygen absorption band near 762 nm and the band's left and right non-absorption shoulders, and a photomultiplier tube is used as the non-imaging sensor of the passive ranging system. Range is estimated by comparing the calculated values of band-average transmission due to oxygen absorption, τO2 , against the predicted curve of τO2 versus range. The method is tested under short-range conditions. Accuracy of 6.5% is achieved with the designed experimental ranging system at the range of 400 m.

17.
Nanotechnology ; 27(32): 325701, 2016 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-27348089

RESUMEN

Despite being known for almost two decades, the use of micro-/nano-electromechanical systems in commercial applications remains a challenge because of stiction, friction, and the wear of the interface. Superlubricity may be the solution to these challenges. In this paper, we study factors affecting the realization of superlubricity. Raman spectroscopy and other methods were used to characterize a graphite interface which can realize superlubricity and another graphite interface which cannot realize superlubricity. Raman spectra of the interfaces were obtained with the mapping mode and then processed to obtain the Raman images of the characteristic peaks. The Raman spectra provided the distribution of the surface defects and probed defects. Combined with atomic force microscopy and x-ray photoelectron spectroscopy, the Raman spectra show that the sp(3) carbons and carbon-oxygen bond stuck at the edge of the graphite mesa are some of the determinants of large-area superlubricity realization. The characterization results can also be used to understand the friction and wear of large-area superlubricity, which are important for development and application of superlubricity. Furthermore, the methods used in this study are useful techniques and tools for the mechanism analysis of other nanometer interfaces.

18.
Sci Rep ; 14(1): 22255, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333346

RESUMEN

It is crucial to precisely calculate temperature utilizing thermal models, which require the determination of thermal parameters that optimally align model outcomes with experimental data. In many instances, the refinement of these models is undertaken within space instruments. This paper introduces an optimization methodology for thermal network models, with the objective of enhancing the accuracy of temperature predictions for aerial cameras. The investigation of internal convective heat transfer coefficients for both cylindrical and planar structures provides an estimation of convective thermal parameters. Based on the identification of thermally sensitive parameters and the reliability evaluation of transient temperature data through the Monte-Carlo simulation, the genetic algorithm is employed to search for global optimal parameter values that minimize the root mean square error (RMSE) between calculated and measured node temperatures. As a result, the optimized model shows significantly improved accuracy in temperature prediction, attaining an RMSE of 1.07 ℃ and reducing the maximum relative error between predicted and experimental results from 33.8 to 3.1%. Furthermore, the flight simulation and thermal control experiments validate the robustness of the optimized model, demonstrating that discrepancies between the observed and predicted temperatures are within 2 °C after re-correcting the external convection heat transfer coefficient value.

19.
Curr Biol ; 34(11): 2359-2372.e9, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38692276

RESUMEN

Host reproduction can be manipulated by bacterial symbionts in various ways. Parthenogenesis induction is the most effective type of reproduction manipulation by symbionts for their transmission. Insect sex is determined by regulation of doublesex (dsx) splicing through transformer2 (tra2) and transformer (tra) interaction. Although parthenogenesis induction by symbionts has been studied since the 1970s, its underlying molecular mechanism is unknown. Here we identify a Wolbachia parthenogenesis-induction feminization factor gene (piff) that targets sex-determining genes and causes female-producing parthenogenesis in the haplodiploid parasitoid Encarsia formosa. We found that Wolbachia elimination repressed expression of female-specific dsx and enhanced expression of male-specific dsx, which led to the production of wasp haploid male offspring. Furthermore, we found that E. formosa tra is truncated and non-functional, and Wolbachia has a functional tra homolog, termed piff, with an insect origin. Wolbachia PIFF can colocalize and interact with wasp TRA2. Moreover, Wolbachia piff has coordinated expression with tra2 and dsx of E. formosa. Our results demonstrate the bacterial symbiont Wolbachia has acquired an insect gene to manipulate the host sex determination cascade and induce parthenogenesis in wasps. This study reveals insect-to-bacteria horizontal gene transfer drives the evolution of animal sex determination systems, elucidating a striking mechanism of insect-microbe symbiosis.


Asunto(s)
Transferencia de Gen Horizontal , Simbiosis , Avispas , Wolbachia , Animales , Wolbachia/fisiología , Wolbachia/genética , Avispas/fisiología , Avispas/microbiología , Avispas/genética , Simbiosis/genética , Femenino , Masculino , Partenogénesis/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Procesos de Determinación del Sexo/genética
20.
Appl Opt ; 52(19): 4706-14, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23842269

RESUMEN

The characteristic size of a collimated Gaussian beam propagating through 1-13 km atmospheric paths is investigated by simulating phase screens using the fast Fourier transform method. Taking a threshold into account, a method to derive a modified centroid and corresponding characteristic radii of the short-term spots is proposed. Effective radius, robust radius, sharpness radius, and maximum radius are analyzed by probability statistics. Furthermore, several parameters representing the energy content of the spots within each radius and the energy duty cycle of the maximum radius are studied. The study shows that, when the modified centroid is taken as a center, the effective radius is more suitable for application after a long propagation path, while the maximum radius is more effective for a short distance. However, when all effective subspots of a short-term image are investigated, the maximum radius is usually utilized, and the energy duty cycle represents the effect probability.

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