AIM: To assess the diagnostic value of computed tomography (CT) imaging in screening for abdominal nonhematogenous disseminated tuberculous lymphadenopathy (TL). METHODS: The CT scans of 12 patients with abdominal non...AIM: To assess the diagnostic value of computed tomography (CT) imaging in screening for abdominal nonhematogenous disseminated tuberculous lymphadenopathy (TL). METHODS: The CT scans of 12 patients with abdominal nonhematogenous disseminated TL suggestive of neoplasm were retrospectively analyzed in this review. The final diagnoses were confirmed by lymph node pathology for seven patients and by laparoscopic surgery for five patients. All of the patients were treated at our institution between April 1995 and August 2009. RESULTS: The sites of involvement were the periportal (n = 6), peripancreatic (n = 3), periaortic (n = 3), and mesenteric (n = 2) regions. On the plain CT scan, the lymphadenopathy showed a heterogeneous isodensity or hypodensity in 11 patients and a low density in one patient. Peripheral enhancement was observed on the dynamic contrast-enhanced CT scans for all patients. In two cases, scans were more revealing during the portal venous and delayed phases. CONCLUSION: Abdominal lymphadenopathy with predominant peripheral rim-like enhancement on the dynamic contrast-enhanced CT scan may suggest a diagnosis of TL.展开更多
In order to find out whether long interspersed elements （LINEs） existed in macro-algae gehomes or not, we tested the LINE homologues in representative families （species）： Gracilaria （G. eucheumoides Harv., G. te...In order to find out whether long interspersed elements （LINEs） existed in macro-algae gehomes or not, we tested the LINE homologues in representative families （species）： Gracilaria （G. eucheumoides Harv., G. tenuistipitata Chang et Xia, and G. textorii （Sur） De-Toni）, Laminaria （L. longissima Miyabe and L. japonica Aresch.）, and Ulva （U. lactuca L. and U. pertusa Kjellm.） during 2004 to 2005. Polymerase Chain Reaction （PCR） was carried out with degenerate oligonucleotide primers designed from LINEs of rice homologues and Cin4 of maize. Cloning and nucleotide sequencing of the PCR products revealed that 4 clones that derived from 3 species of Gracilaria have LINE homologues. The nucleotide sequences of the 4 LINE homologues diverged greatly, but the amino acid sequences deduced from them were relatively conserved. The endonuclease regions of the LINE homologues greatly diverged from that of other plants, but they had closer phylogenetic relationship to Zepp elements in Chlorella sp., which indicated that sequence divergence by vertical transmission has been a major influence on the evolution of algal LINEs.展开更多
We investigate the transient phenomenon or property of the propagationof an optical probe field in a medium consisting of many A-type three-level atoms coupled to this probe field and a classical driven field. We obse...We investigate the transient phenomenon or property of the propagationof an optical probe field in a medium consisting of many A-type three-level atoms coupled to this probe field and a classical driven field. We observe a hidden symmetry and obtain an exact solution for this light propagation problem by means of the spectral generating method. This solution enlightens us to propose a practical protocol implementing the quantum memory robust for quantum decoherence in a crystal. As a transient dynamic process this solution also manifests an exotic result that a wave-packet of light will split into three packets propagating at different group velocities. It is argued that "super-luminal group velocity" and "sub-luminal group velocity" can be observed simultaneously in the same system. This interesting phenomenon is expected to be demonstrated experimentally.展开更多
The application of support vector machines to forecasting problems is becoming popular, lately. Several comparisons between neural networks trained with error backpropagation and support vector machines have shown adv...The application of support vector machines to forecasting problems is becoming popular, lately. Several comparisons between neural networks trained with error backpropagation and support vector machines have shown advantage for the latter in different domains of application. However, some difficulties still deteriorate the performance of the support vector machines. The main one is related to the setting of the hyperparameters involved in their training. Techniques based on meta-heuristics have been employed to determine appropriate values for those hyperparameters. However, because of the high noneonvexity of this estimation problem, which makes the search for a good solution very hard, an approach based on Bayesian inference, called relevance vector machine, has been proposed more recently. The present paper aims at investigating the suitability of this new approach to the short-term load forecasting problem.展开更多
OBJECTIVE: To study the effect and mechanism of the peripheral blood mononuclear cell (PBMC) invasion by HBV on artificial immunization in newborns. METHODS: Fifty-two newborns of HBsAg positive mothers were immunized...OBJECTIVE: To study the effect and mechanism of the peripheral blood mononuclear cell (PBMC) invasion by HBV on artificial immunization in newborns. METHODS: Fifty-two newborns of HBsAg positive mothers were immunized with HBIG (hepatitis B immunoglobulin) and HBVac (hepatitis B vaccine) and were followed up for 7 months. The newborns' HBV-DNA in serum and in the PBMCs was detected with nested-PCR; anti-HBs was tested with solid phase radioimmunoassay (SP-RIA). PBMCs isolated from newborn peripheral blood were incubated in the presence of PHA or purified HBsAg. Interleukin-2 (IL-2) level in culture supernatants of activated cells was detected by ELISA. RESULTS: The failure rate of immunization was higher in infants with positive HBV-DNA in PBMCs than those with negative HBV-DNA (P展开更多
A model which incorporates some of the basic epidemiological features of the co- dynamics of malaria and tuberculosis （TB） is formulated and the effectiveness of current intervention strategies of these two diseases...A model which incorporates some of the basic epidemiological features of the co- dynamics of malaria and tuberculosis （TB） is formulated and the effectiveness of current intervention strategies of these two diseases is analyzed. The malaria-only and TB-only models are considered first. Global stability disease-free steady states of the two sub- models does not hold due to the co-existence of stable disease-free with stable endemic equilibria, a phenomenon known as backward bifurcation. The dynamics of the dual malari^TB model with intervention strategies are also analyzed. Numerical simulations of the malaria-TB model are carried out to determine whether the two diseases can co- exist. Lastly, sensitivity analysis on key parameters that drive the disease dynamics is performed in order to identify their relative importance to disease transmission.展开更多
Molecular dynamics simulation was performed to investigate the influence of twin boundary （TB） spacing on crack propaga- tion of AI. This study reveals the orientation of initial crack may affect the mechanism of cr...Molecular dynamics simulation was performed to investigate the influence of twin boundary （TB） spacing on crack propaga- tion of AI. This study reveals the orientation of initial crack may affect the mechanism of crack growth obviously. TB strengthens A1 when the crack orientation is parallel with TB because of the hinderance of TB to the emission of the disloca- tions. The results indicate that there is an optimal TB spacing for mechanical properties of the A1, exhibiting reverse HP （Hall-Petch） and HP effect when the TB spacing is near the critical TB spacing. Furthermore, we find that there is a yield strength hardening effect in nanotwinned A1 when the crack orientation is perpendicular to the TB, and the Young＇s modulus is smaller in the nanotwinned A1 than that of twin free A1. The studies also demonstrate that this distinctive deformation behavior is related to nucleation of dislocations and the repulsive force of TB to the dislocations and crack propagation, as well as the distance between the crack tip and the TB.展开更多
A deterministic model for evaluating the impact of voluntary testing and treatment on the transmission dynamics of tuberculosis is formulated and analyzed. The epidemio- logical threshold, known as the reproduction nu...A deterministic model for evaluating the impact of voluntary testing and treatment on the transmission dynamics of tuberculosis is formulated and analyzed. The epidemio- logical threshold, known as the reproduction number is derived and qualitatively used to investigate the existence and stability of the associated equilibrium of the model system. The disease-free equilibrium is shown to be locally-asymptotically stable when the reproductive number is less than unity, and unstable if this threshold parameter exceeds unity. It is shown, using the Centre Manifold theory, that the model undergoes the phenomenon of backward bifurcation where the stable disease-free equilibrium co- exists with a stable endemic equilibrium when the associated reproduction number is less than unity. The analysis of the reproduction number suggests that voluntary tuber- culosis testing and treatment may lead to effective control of tuberculosis. Furthermore, numerical simulations support the fact that an increase voluntary tuberculosis testing and treatment have a positive impact in controlling the spread of tuberculosis in the community.展开更多
文摘AIM: To assess the diagnostic value of computed tomography (CT) imaging in screening for abdominal nonhematogenous disseminated tuberculous lymphadenopathy (TL). METHODS: The CT scans of 12 patients with abdominal nonhematogenous disseminated TL suggestive of neoplasm were retrospectively analyzed in this review. The final diagnoses were confirmed by lymph node pathology for seven patients and by laparoscopic surgery for five patients. All of the patients were treated at our institution between April 1995 and August 2009. RESULTS: The sites of involvement were the periportal (n = 6), peripancreatic (n = 3), periaortic (n = 3), and mesenteric (n = 2) regions. On the plain CT scan, the lymphadenopathy showed a heterogeneous isodensity or hypodensity in 11 patients and a low density in one patient. Peripheral enhancement was observed on the dynamic contrast-enhanced CT scans for all patients. In two cases, scans were more revealing during the portal venous and delayed phases. CONCLUSION: Abdominal lymphadenopathy with predominant peripheral rim-like enhancement on the dynamic contrast-enhanced CT scan may suggest a diagnosis of TL.
基金Supported by the NSFC (No. 40376049 and No. 30500383)Shandong Agricultural Seed Stock Breeding Project and Knowledge In-novation Program of Chinese Academy of Sciences (KSCX2-YW-N-47-02).
文摘In order to find out whether long interspersed elements （LINEs） existed in macro-algae gehomes or not, we tested the LINE homologues in representative families （species）： Gracilaria （G. eucheumoides Harv., G. tenuistipitata Chang et Xia, and G. textorii （Sur） De-Toni）, Laminaria （L. longissima Miyabe and L. japonica Aresch.）, and Ulva （U. lactuca L. and U. pertusa Kjellm.） during 2004 to 2005. Polymerase Chain Reaction （PCR） was carried out with degenerate oligonucleotide primers designed from LINEs of rice homologues and Cin4 of maize. Cloning and nucleotide sequencing of the PCR products revealed that 4 clones that derived from 3 species of Gracilaria have LINE homologues. The nucleotide sequences of the 4 LINE homologues diverged greatly, but the amino acid sequences deduced from them were relatively conserved. The endonuclease regions of the LINE homologues greatly diverged from that of other plants, but they had closer phylogenetic relationship to Zepp elements in Chlorella sp., which indicated that sequence divergence by vertical transmission has been a major influence on the evolution of algal LINEs.
文摘We investigate the transient phenomenon or property of the propagationof an optical probe field in a medium consisting of many A-type three-level atoms coupled to this probe field and a classical driven field. We observe a hidden symmetry and obtain an exact solution for this light propagation problem by means of the spectral generating method. This solution enlightens us to propose a practical protocol implementing the quantum memory robust for quantum decoherence in a crystal. As a transient dynamic process this solution also manifests an exotic result that a wave-packet of light will split into three packets propagating at different group velocities. It is argued that "super-luminal group velocity" and "sub-luminal group velocity" can be observed simultaneously in the same system. This interesting phenomenon is expected to be demonstrated experimentally.
文摘The application of support vector machines to forecasting problems is becoming popular, lately. Several comparisons between neural networks trained with error backpropagation and support vector machines have shown advantage for the latter in different domains of application. However, some difficulties still deteriorate the performance of the support vector machines. The main one is related to the setting of the hyperparameters involved in their training. Techniques based on meta-heuristics have been employed to determine appropriate values for those hyperparameters. However, because of the high noneonvexity of this estimation problem, which makes the search for a good solution very hard, an approach based on Bayesian inference, called relevance vector machine, has been proposed more recently. The present paper aims at investigating the suitability of this new approach to the short-term load forecasting problem.
文摘OBJECTIVE: To study the effect and mechanism of the peripheral blood mononuclear cell (PBMC) invasion by HBV on artificial immunization in newborns. METHODS: Fifty-two newborns of HBsAg positive mothers were immunized with HBIG (hepatitis B immunoglobulin) and HBVac (hepatitis B vaccine) and were followed up for 7 months. The newborns' HBV-DNA in serum and in the PBMCs was detected with nested-PCR; anti-HBs was tested with solid phase radioimmunoassay (SP-RIA). PBMCs isolated from newborn peripheral blood were incubated in the presence of PHA or purified HBsAg. Interleukin-2 (IL-2) level in culture supernatants of activated cells was detected by ELISA. RESULTS: The failure rate of immunization was higher in infants with positive HBV-DNA in PBMCs than those with negative HBV-DNA (P
文摘A model which incorporates some of the basic epidemiological features of the co- dynamics of malaria and tuberculosis （TB） is formulated and the effectiveness of current intervention strategies of these two diseases is analyzed. The malaria-only and TB-only models are considered first. Global stability disease-free steady states of the two sub- models does not hold due to the co-existence of stable disease-free with stable endemic equilibria, a phenomenon known as backward bifurcation. The dynamics of the dual malari^TB model with intervention strategies are also analyzed. Numerical simulations of the malaria-TB model are carried out to determine whether the two diseases can co- exist. Lastly, sensitivity analysis on key parameters that drive the disease dynamics is performed in order to identify their relative importance to disease transmission.
基金supported by the National Natural Science Foundation of China(Grant No.10902083)the Program for New Century Excellent Talents in University(Grant No.NCET-12-1046)the Program for New Scientific and Technological Star of Shaanxi Province(Grant No.2012KJXX-39)
文摘Molecular dynamics simulation was performed to investigate the influence of twin boundary （TB） spacing on crack propaga- tion of AI. This study reveals the orientation of initial crack may affect the mechanism of crack growth obviously. TB strengthens A1 when the crack orientation is parallel with TB because of the hinderance of TB to the emission of the disloca- tions. The results indicate that there is an optimal TB spacing for mechanical properties of the A1, exhibiting reverse HP （Hall-Petch） and HP effect when the TB spacing is near the critical TB spacing. Furthermore, we find that there is a yield strength hardening effect in nanotwinned A1 when the crack orientation is perpendicular to the TB, and the Young＇s modulus is smaller in the nanotwinned A1 than that of twin free A1. The studies also demonstrate that this distinctive deformation behavior is related to nucleation of dislocations and the repulsive force of TB to the dislocations and crack propagation, as well as the distance between the crack tip and the TB.
文摘A deterministic model for evaluating the impact of voluntary testing and treatment on the transmission dynamics of tuberculosis is formulated and analyzed. The epidemio- logical threshold, known as the reproduction number is derived and qualitatively used to investigate the existence and stability of the associated equilibrium of the model system. The disease-free equilibrium is shown to be locally-asymptotically stable when the reproductive number is less than unity, and unstable if this threshold parameter exceeds unity. It is shown, using the Centre Manifold theory, that the model undergoes the phenomenon of backward bifurcation where the stable disease-free equilibrium co- exists with a stable endemic equilibrium when the associated reproduction number is less than unity. The analysis of the reproduction number suggests that voluntary tuber- culosis testing and treatment may lead to effective control of tuberculosis. Furthermore, numerical simulations support the fact that an increase voluntary tuberculosis testing and treatment have a positive impact in controlling the spread of tuberculosis in the community.
