Wolbachia are intracellular symbionts that infect a wide range of arthropods and filarial nematodes. Aphids are engaged in diverse and complex relationships withtheir endosymbionts. Four supergroups (A, B, M and N) ...Wolbachia are intracellular symbionts that infect a wide range of arthropods and filarial nematodes. Aphids are engaged in diverse and complex relationships withtheir endosymbionts. Four supergroups (A, B, M and N) of Wolbachia were previously detected in aphids and supergroups M and N were only found in aphids. In this study, wedetected and described Wolbachia infections in natural populations of aphids in China. Three supergroups (A, B and M) were found in the examined aphid species. SupergroupM was preponderant, whereas supergroups A and B were only detected in certain species. Supergroup N was not found in this study. There were four infection patterns of Wolbachiain aphids, namely, infection with supergroup M alone, co-infection with supergroups A and M, co-infection with supergroups B and M, and co-infection with supergroups A, Band M. The pattern of infection only with supergroup M was universal and was tbund in all evaluated subfamilies. Only two subfamilies, Aphidinae and Lachninae, manifestedto present all four infection patterns. Three patterns were observed in Calaphidinae (M, A&M, B&M) and Eriosomatinae (M, B&M, A&B&M). Two patterns were observed inthe Anoeciinae (M, A&M) and Greenideinae (M, B&M), and only one pattern (M) was observed in the remaining families and/or subfamilies of Aphidoidea. These results indi-cated that Wolbachia infections in Chinese aphids are widespread. Phylogenetic analyses suggest that Wolbachia supergroup M spread rapidly and recently among all host speciesof aphids in China. Reasons for this spread and its mechanisms are discussed along with the possible effects of Wolbachia on their aphid hosts.展开更多
The concept of Terahertz Field-Induced Second Harmonic(TFISH)Generation is revisited to introduce a single-shot detection scheme based on third order nonlinearities.Focused specifcally on the further development of TH...The concept of Terahertz Field-Induced Second Harmonic(TFISH)Generation is revisited to introduce a single-shot detection scheme based on third order nonlinearities.Focused specifcally on the further development of THz plasma-based sources,we begin our research by reimagining the TFISH system to serve as a direct plasma diagnostic.In this work,an optical probe beam is used to mix directly with the strong ponderomotive current associated with laser-induced ionization.A four-wave mixing(FWM)process then generates a strong second-harmonic optical wave because of the mixing of the probe beam with the nonlinear current components oscillating at THz frequencies.The observed conversion efciency is high enough that for the frst time,the TFISH signal appears visible to the human eye.We perform spectral,spatial,and temporal analysis on the detected second-harmonic frequency and show its direct relationship to the nonlinear current.Further,a method to detect incoherent and coherent THz inside plasma flaments is devised using spatio-temporal couplings.The single-shot detection confgurations are theoretically described using a combination of expanded FWM models with Kostenbauder and Gaussian Q-matrices.We show that the retrieved temporal traces for THz radiation from single-and twocolor laser-induced air-plasma sources match theoretical descriptions very well.High temporal resolution is shown with a detection bandwidth limited only by the spatial extent of the probe laser beam.Large detection bandwidth and temporal characterization is shown for THz radiation confned to under-dense plasma flaments induced by<100 fs lasers below the relativistic intensity limit.展开更多
Full impact damage tolerance assessment requires the ability to properly mimic the repeated impact response and damage behaviour of composite materials using quasi-static approximations.To this aim,this paper reports ...Full impact damage tolerance assessment requires the ability to properly mimic the repeated impact response and damage behaviour of composite materials using quasi-static approximations.To this aim,this paper reports an experimental investigation evaluating two quasi-static methods for mimicking repeated impact response and damage behaviour of Carbon Fibre Reinforced Polymer(CFRP)composite laminates.In this study,an 8.45-J single impact was repeated 225 times and mimicked with 225 times 6.51-J quasi-static(energy equivalent)indentations and with 225 quasi-static(force equivalent)indentations following the recorded impact peak force variation.Results show that the loading rate and the inertial effect are the two major factors affecting the responses of the composite laminates under out-of-plane concentrated loading.Both the energyand force-equivalent quasi-static indentations failed to reproduce the impact responses greatly associated with high loading rate and inertial effect.The force-equivalent quasi-static indentations were performed in a semi-automatic way and induced damage states more similar to those of the repeated impacts than those of the energy-equivalent quasi-static indentations,whereas the latter can be better automated and has better reproducibility compared to that of the repeated impact responses,as it is less dependent on high loading rate and inertial effect.展开更多
The discovery of a strong association between hepatitis C virus(HCV) infection and mixed cryoglobulinemia(MC) has led to an increasingly rare diagnosis of idiopathic essential MC(EMC).The incidence of EMC is high in r...The discovery of a strong association between hepatitis C virus(HCV) infection and mixed cryoglobulinemia(MC) has led to an increasingly rare diagnosis of idiopathic essential MC(EMC).The incidence of EMC is high in regions where there is a comparatively low HCV infection burden and low in areas of high infection prevalence,including HCV.The diagnosis of EMC requires an extensive laboratory investigation to exclude all possible causes of cryoglobulin formation.In addition,although cryoglobulin testing is simple,improper testing conditions will result in false negative results.Here,we present a 46-year-old female patient with a case of EMC with dermatological and renal manifestations,highlighting the importance of extensive investigation to reacha proper diagnosis.We review the need for appropriate laboratory testing,which is often neglected in clinical practice and which can result in false negative results.This review also emphasizes the significance of an extended testing repertoire necessary for better patient management.Despite a strong association of MC with HCV infection and other causes that lead to cryoglobulin formation,EMC remains a separate entity.Correct diagnosis requires proper temperature regulation during sample handling,as well as characterization and quantification of the cryoprecipitate.Inclusion of rheumatoid factor activity and complement levels in the cryoglobulin test-panel promotes better patient management and monitoring.Consensus guidelines should be developed and implemented for cryoglobulin detection and the diagnosis of cryoglobulinemic syndrome,which will reduce variability in inter-laboratory reporting.展开更多
We employed a multiplex polymerase chain reaction (PCR) coupled with capillary electrophoresis (mPCR-CE) targeting six Clostridium difficile genes, including tPi, tcdA, tcdB, cdtA, cdtB, and a deletion in tcdC for...We employed a multiplex polymerase chain reaction (PCR) coupled with capillary electrophoresis (mPCR-CE) targeting six Clostridium difficile genes, including tPi, tcdA, tcdB, cdtA, cdtB, and a deletion in tcdC for simultaneous detection and characterization of toxigenic C. difficile directly from fecal specimens. The mPCR-CE had a limit of detection of 10 colony-forming units per reaction with no cross-reactions with other related bacterial genes. Clinical validation was performed on 354 consecutively collected stool specimens from patients with suspected C. difficile infection and 45 isolates. The results were compared with a reference standard combined with BD MAX Cdiff, real-time cell analysis assay (RTCA), and mPCR-CE. The toxigenic C. difficile species were detected in 36 isolates and 45 stool specimens by the mPCR-CE, which provided a positive rate of 20.3% (81/399). The mPCR-CE had a specificity of 97,2% and a sensitivity of 96.0%, which was higher than RTCA (χ^2 = 5.67, P = 0.017) but lower than BD MAX Cdiff (P = 0.245). Among the 45 strains, 44 (97.8%) were determined as non- ribotype 027 by the mPCR-CE, which was fully agreed with PCR ribotyping. Even though ribotypes 017 (n = 8, 17.8%), 001 (n = 6, 13.3%), and 012 (n = 7, 15.6%) were predominant in this region, ribotype 027 was an important genotype monitored routinely. The mPCR-CE provided an alternative diagnosis tool for the simultaneous detection of toxigenic C. difficile in stool and potentially differentiated between RT027 and non-RT027.展开更多
文摘Wolbachia are intracellular symbionts that infect a wide range of arthropods and filarial nematodes. Aphids are engaged in diverse and complex relationships withtheir endosymbionts. Four supergroups (A, B, M and N) of Wolbachia were previously detected in aphids and supergroups M and N were only found in aphids. In this study, wedetected and described Wolbachia infections in natural populations of aphids in China. Three supergroups (A, B and M) were found in the examined aphid species. SupergroupM was preponderant, whereas supergroups A and B were only detected in certain species. Supergroup N was not found in this study. There were four infection patterns of Wolbachiain aphids, namely, infection with supergroup M alone, co-infection with supergroups A and M, co-infection with supergroups B and M, and co-infection with supergroups A, Band M. The pattern of infection only with supergroup M was universal and was tbund in all evaluated subfamilies. Only two subfamilies, Aphidinae and Lachninae, manifestedto present all four infection patterns. Three patterns were observed in Calaphidinae (M, A&M, B&M) and Eriosomatinae (M, B&M, A&B&M). Two patterns were observed inthe Anoeciinae (M, A&M) and Greenideinae (M, B&M), and only one pattern (M) was observed in the remaining families and/or subfamilies of Aphidoidea. These results indi-cated that Wolbachia infections in Chinese aphids are widespread. Phylogenetic analyses suggest that Wolbachia supergroup M spread rapidly and recently among all host speciesof aphids in China. Reasons for this spread and its mechanisms are discussed along with the possible effects of Wolbachia on their aphid hosts.
基金supported by the Air Force Ofce of Scientifc Research(FA9550-21-1-0389 and FA9550-21-1-0300)National Science Foundation(Grant No.ECCS-2152081).
文摘The concept of Terahertz Field-Induced Second Harmonic(TFISH)Generation is revisited to introduce a single-shot detection scheme based on third order nonlinearities.Focused specifcally on the further development of THz plasma-based sources,we begin our research by reimagining the TFISH system to serve as a direct plasma diagnostic.In this work,an optical probe beam is used to mix directly with the strong ponderomotive current associated with laser-induced ionization.A four-wave mixing(FWM)process then generates a strong second-harmonic optical wave because of the mixing of the probe beam with the nonlinear current components oscillating at THz frequencies.The observed conversion efciency is high enough that for the frst time,the TFISH signal appears visible to the human eye.We perform spectral,spatial,and temporal analysis on the detected second-harmonic frequency and show its direct relationship to the nonlinear current.Further,a method to detect incoherent and coherent THz inside plasma flaments is devised using spatio-temporal couplings.The single-shot detection confgurations are theoretically described using a combination of expanded FWM models with Kostenbauder and Gaussian Q-matrices.We show that the retrieved temporal traces for THz radiation from single-and twocolor laser-induced air-plasma sources match theoretical descriptions very well.High temporal resolution is shown with a detection bandwidth limited only by the spatial extent of the probe laser beam.Large detection bandwidth and temporal characterization is shown for THz radiation confned to under-dense plasma flaments induced by<100 fs lasers below the relativistic intensity limit.
基金the financial support from the China Scholarship Council(No.CSC201806290014).
文摘Full impact damage tolerance assessment requires the ability to properly mimic the repeated impact response and damage behaviour of composite materials using quasi-static approximations.To this aim,this paper reports an experimental investigation evaluating two quasi-static methods for mimicking repeated impact response and damage behaviour of Carbon Fibre Reinforced Polymer(CFRP)composite laminates.In this study,an 8.45-J single impact was repeated 225 times and mimicked with 225 times 6.51-J quasi-static(energy equivalent)indentations and with 225 quasi-static(force equivalent)indentations following the recorded impact peak force variation.Results show that the loading rate and the inertial effect are the two major factors affecting the responses of the composite laminates under out-of-plane concentrated loading.Both the energyand force-equivalent quasi-static indentations failed to reproduce the impact responses greatly associated with high loading rate and inertial effect.The force-equivalent quasi-static indentations were performed in a semi-automatic way and induced damage states more similar to those of the repeated impacts than those of the energy-equivalent quasi-static indentations,whereas the latter can be better automated and has better reproducibility compared to that of the repeated impact responses,as it is less dependent on high loading rate and inertial effect.
文摘The discovery of a strong association between hepatitis C virus(HCV) infection and mixed cryoglobulinemia(MC) has led to an increasingly rare diagnosis of idiopathic essential MC(EMC).The incidence of EMC is high in regions where there is a comparatively low HCV infection burden and low in areas of high infection prevalence,including HCV.The diagnosis of EMC requires an extensive laboratory investigation to exclude all possible causes of cryoglobulin formation.In addition,although cryoglobulin testing is simple,improper testing conditions will result in false negative results.Here,we present a 46-year-old female patient with a case of EMC with dermatological and renal manifestations,highlighting the importance of extensive investigation to reacha proper diagnosis.We review the need for appropriate laboratory testing,which is often neglected in clinical practice and which can result in false negative results.This review also emphasizes the significance of an extended testing repertoire necessary for better patient management.Despite a strong association of MC with HCV infection and other causes that lead to cryoglobulin formation,EMC remains a separate entity.Correct diagnosis requires proper temperature regulation during sample handling,as well as characterization and quantification of the cryoprecipitate.Inclusion of rheumatoid factor activity and complement levels in the cryoglobulin test-panel promotes better patient management and monitoring.Consensus guidelines should be developed and implemented for cryoglobulin detection and the diagnosis of cryoglobulinemic syndrome,which will reduce variability in inter-laboratory reporting.
文摘We employed a multiplex polymerase chain reaction (PCR) coupled with capillary electrophoresis (mPCR-CE) targeting six Clostridium difficile genes, including tPi, tcdA, tcdB, cdtA, cdtB, and a deletion in tcdC for simultaneous detection and characterization of toxigenic C. difficile directly from fecal specimens. The mPCR-CE had a limit of detection of 10 colony-forming units per reaction with no cross-reactions with other related bacterial genes. Clinical validation was performed on 354 consecutively collected stool specimens from patients with suspected C. difficile infection and 45 isolates. The results were compared with a reference standard combined with BD MAX Cdiff, real-time cell analysis assay (RTCA), and mPCR-CE. The toxigenic C. difficile species were detected in 36 isolates and 45 stool specimens by the mPCR-CE, which provided a positive rate of 20.3% (81/399). The mPCR-CE had a specificity of 97,2% and a sensitivity of 96.0%, which was higher than RTCA (χ^2 = 5.67, P = 0.017) but lower than BD MAX Cdiff (P = 0.245). Among the 45 strains, 44 (97.8%) were determined as non- ribotype 027 by the mPCR-CE, which was fully agreed with PCR ribotyping. Even though ribotypes 017 (n = 8, 17.8%), 001 (n = 6, 13.3%), and 012 (n = 7, 15.6%) were predominant in this region, ribotype 027 was an important genotype monitored routinely. The mPCR-CE provided an alternative diagnosis tool for the simultaneous detection of toxigenic C. difficile in stool and potentially differentiated between RT027 and non-RT027.