Search

β decay of proton-rich nuclei plays an important role in exploring isospin mixing. The β decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through β-delayed two-proton emission (β2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P β decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in β-decay experiments.

The beta-delayed two-proton (beta 2p) decay of S-27 was studied using a state-of-the-art silicon array and Clover-type HPGe detectors. An energy peak at 6372(15) keV with a branching ratio of 2.4(5)% in the decay-energy spectrum was identified as a two-proton transition via the isobaric-analog state in P-27 to the ground state of Al-25 in the beta decay of S-27. Two-proton angular correlations were measured by the silicon array to study the mechanism of two-proton emission. Based on experimental results and Monte Carlo simulations, it was found that the main mechanism for the emission of beta 2p by S-27 is of sequential nature.

A new α-emitting isotope ^{214}U, produced by the fusion-evaporation reaction ^{182}W(^{36}Ar,4n)^{214}U, was identified by employing the gas-filled recoil separator SHANS and the recoil-α correlation technique. More precise α-decay properties of even-even nuclei ^{216,218}U were also measured in the reactions of ^{40}Ar, ^{40}Ca beams with ^{180,182,184}W targets. By combining the experimental data, improved α-decay reduced widths δ^{2} for the even-even Po-Pu nuclei in the vicinity of the magic neutron number N=126 are deduced. Their systematic trends are discussed in terms of the N_{p}N_{n} scheme in order to study the influence of proton-neutron interaction on α decay in this region of nuclei. It is strikingly found that the reduced widths of ^{214,216}U are significantly enhanced by a factor of two as compared with the N_{p}N_{n} systematics for the 84≤Z≤90 and N126 even-even nuclei. The abnormal enhancement is interpreted by the strong monopole interaction between the valence protons and neutrons occupying the π1f_{7/2} and ν1f_{5/2} spin-orbit partner orbits, which is supported by the large-scale shell model calculation.

RIBLL Collaboration: et al., The mass of 27P is expected to impact the X-ray burst (XRB) model predictions of burst light curves and the composition of the burst ashes, but large uncertainties and inconsistencies still exist in the reported 27P masses. We have used the β-decay spectroscopy of 27S to determine the most precise mass excess of 7P to date to be −659(9)keV, which is 63 keV (2.3σ) higher and a factor of 3 more precise than the value recommended in the 2016 Atomic Mass Evaluation. Based on the new 27P mass, the 26Si(p, γ)27P reaction rate and its uncertainty were recalculated using Monte Carlo techniques. We also estimated the previously unknown mass excess of 27S to be 17678(77) keV, based on the measured β-delayed two-proton energy and the Coulomb displacement energy relations. The impact of these well-constrained masses and reaction rates on the modeling of the explosive astrophysical scenarios has been investigated by post-processing XRB and hydrodynamic nova models. Compared to the model calculations based on the masses and rates from databases, the abundance of A =26 in the burst ashes is increased by a factor of 2.4, while no substantial change was found in the XRB energy generation rate or the light curve. Our calculation also suggests that 27S is not a significant waiting point in the rapid proton capture process, and the change of the 26Si(p, γ)27P reaction rate is not sufficiently large to affect the conclusion previously drawn on the nova contribution to the synthesis of galactic 26Al., This work is supported by the Ministry of Science and Technology of China under the National Key R&D Programs Nos. 2018YFA0404404 and 2016YFA0400503, and the National Natural Science Foundation of China under Grants Nos. 11635015, 11805120, U1632136, 11705244, U1432246, 11775316, U1732145, 11705285, U1867212, 11805280, 11825504, 11675229, and 11490562, and the Youth Innovation Promotion Association of Chinese Academy of Sciences under Grant No. 2019406, and the Continuous Basic Scientific Research Project under Grant No. WDJC-2019-13, and the China Postdoctoral Science Foundation under Grants Nos. 2017M621442 and 2017M621035, and the Office of China Postdoctoral Council under the International Postdoctoral Exchange Fellowship Program (Talent-Dispatch Program) No. 20180068. Jordi José acknowledges funding from the Spanish MINECO grant AYA2017-86274-P, by the E.U. FEDER funds, and by the AGAUR/Generalitat de Catalunya grant SGR-661/2017.

$\beta$ decay of $^{26}$P was used to populate the astrophysically important $E_x=$5929.4(8) keV $J^{\pi}=3{^+}$ state of $^{26}$Si. Both $\beta$-delayed proton at 418(8) keV and gamma ray at 1742(2) keV emitted from this state were measured simultaneously for the first time with corresponding absolute intensities of 11.1(12)\% and 0.59(44)\%, respectively. Besides, shell model calculations with weakly bound effects were performed to investigate the decay properties of other resonant states and a spin-parity of $4^+$ rather than $0^+$ was favored for the $E_x=$5945.9(40) keV state. Combining the experimental results and theoretical calculations, $^{25}$Al($p,\gamma$)$^{26}$Si reaction rate in explosive hydrogen burning environments was calculated and compared with previous studies.

Background: Beta-decay spectroscopy provides valuable nuclear physics input for thermonuclear reaction rates of astrophysical interest and stringent test for shell-model theories far from the stability line. Purpose: The available decay properties of proton drip-line nucleus $^{27}$S is insufficient to constrain the properties of the key resonance in $^{26}$Si$(p,\gamma)^{27}$P reaction rate and probe the possible isospin asymmetry. The decay scheme of $^{27}$S is complicated and far from being understood, which has motivated but also presented challenges for our experiment. Method: The $^{27}$S ions were implanted into a double-sided silicon strip detector array surrounded by the high-purity germanium detectors, where the $\beta$-delayed protons and $\gamma$ rays were measured simultaneously. Results: The improved spectroscopic properties including the precise half-life of $^{27}$S, the excitation energies, $\beta$-decay branching ratios, log~$ft$ values, and $B$(GT) values for the states of $^{27}$P populated in the $\beta$ decay of $^{27}$S were measured and compared to the $^{27}$Mg mirror states and the shell-model calculations. The present work has expanded greatly on the previously established decay scheme of $^{27}$S. Conclusions: The precise proton-separation energy of $^{27}$P, the energy and the ratio between $\gamma$ and proton partial widths of the $3/2^+$ resonance were obtained, thereby determining the $^{26}$Si$(p,\gamma)^{27}$P reaction rate based mainly on experimental constraints. The first evidence for the observation of a large isospin asymmetry for the mirror decays of $^{27}$S and $^{27}$Na is also provided. The experimental spectroscopic information can be reproduced by the shell-model calculation taking the weakly bound effect of the proton $1s_{1/2}$ orbit into account.

Research on the new tasks and capabilities are required for ammunition in the future intelligent air combat, the concept of smart munitions is put forward, and the intelligent development approaches of single equipment intelligence, system intelligence, swarm intelligence and system of system intelligence are put forward. This paper classifies and analyzes the relevant projects currently carried out by the US military, and on this basis summarizes the development trend of airborne smart munitions. Finally, some suggestions for the development of airborne smart munitions in China are given. The above research results will provide reference for the construction of intelligent equipment system of airborne intelligent ammunition and the direction of technology research.

The decay of 218Pa was investigated by means of α and γ spectroscopy. The nucleus was produced in the fusion reaction 40Ar+182W and separated in flight by the gas-filled recoil separator SHANS (Spectrometer for Heavy Atoms and Nuclear Structure). The known α decays of 218Pa were measured with improved precision and newly assigned to be originating from the ground state, which clarified the ambiguities in their previous assignments. In addition, a new isomeric state in 218Pa decaying with α-particle energies of 9691(15) keV, 9595(21) keV and a half-life of 135−32+62 μs was identified. The spins and parities of the involved states were tentatively assigned on the basis of the systematic α-decay properties of the odd-proton N=127 isotones and shell model calculations. Keywords: Odd-proton N=127 isotones, Isomeric state, α-particle energy, Half-life, Shell model calculation, Spin and parity

The aim of this study was to breed a target genotype variety based on the identified chalkiness marker-QTL (quantitative trait locus) associations in rice. First, a permanent mapping population of rice that consisted of 525 recombinant inbred lines (RILs), which were derived from Zhenshan 97/Minghui 63, was used to identify QTLs with additive effects for rice quantitative traits and percentage of grain chalkiness (PGC). Subsequently, based on the identified QTLs in rice, the molecular marker 68923-PGC was selected to screen the low chalkiness rice line. Then, using the integration of molecular marker breeding and traditional breeding, we analyzed the genotype and phenotype of inbred lines from 525 RILs; we identified one rice variety with particularly high yields, good taste, and broad adaptability. The new variety was temporarily named RIL10, which was a high quality, high yield, and broadly adaptable variety, and it is predominantly a feature that has contributed to its geographical adaptability, which would be planted from 35°E to 18°E in Chinain China, where 2/3 of rice production occurs. RIL10 was a marker-assisted selection breeding achievement for producing a high quality, high yield, and broadly adaptable rice variety.

To investigate the incidence of drug resistance in adult AIDS patients receiving antiretroviral treatment(ART)and influencing factors in Dehong prefecture, Yunnan province during 2012-2014.For this cohort study, all the AIDS patients aged over 15 and receiving ART in Dehong were screened for HIV drug resistance in 2012, and 3 715 patients who had received ART for more than 6 months were enrolled for 12 months and 24 months follow up.Among the 3 715 patients, 56.6% were males, 72.6% were aged 26-45 years and 76.0% were married. The main treatment regimen was nevirapine(NVP)+ lamivudine(3TC)+ zidovudine(AZT)(38.2%). A total of 3 556 patients(95.7%)received at least one viral load testing during the two years follow-up, among them 253(7.1%)patients had VL≥1 000 copies/ml, in which 211(83.4%)received drug resistance related gene mutation testing, the results indicated that the drug resistance developed in 52 and 39 patients in 2013 and 2014(1.43 per 100 person years and 0.88 per 100 person years)respectively. The overall HIV drug incidence was 1.13 per 100 person years. Multivariate regression analysis indicated that age ≤25 years, to be infected through drug use, treatment regimen as D4T+ 3TC +NVP and baseline CD4(+) T cells ≤200 cells/μl were the risk factor of HIV drug resistance. Eleven HIV gene subtypes were detected in the 82 patients with newly developed drug resistance, CRF_BC was predominant(31.7%), followed by CRF01_AE(22.0%)and C(19.5%). Ten patients were infected with mixed subtypes of CRF_BC/B', CRF_BC/CRF_01B and CRF_BC/C. Most of the 82 patients were resistant to NRTIs and NNRTIs, the main mutation loci were M184V and K103N.The incidence of drug resistance in adult AIDS patients receiving ART was relatively low in Dehong. However, it is necessary to conduct the health education in young people and drug users to improve the treatment compliance and strengthen the surveillance for HIV drug resistance.

Background: Enterobacter cloacae (E. cloacae) infection has the highest mortality rate among Enterobacter infections. This study aimed to determine the prevalence and the transmission route of the class I integron, qnr genes, and CTX-M ESBLs genes in clinical isolates and to analyse the association between the prevalence of MDR genes and the antibiotic resistance of E. cloacae. Materials and Methods: The antibiotic susceptibility was tested the agar dilution method. The class I integron, qnr genes, and CTX-M ESBLs genes were detected by polymerase chain reaction (PCR). The prevalence data were analysed with the Chi-square test. Results: In the 100 clinical isolates, the class I integron-positive rate was 65%, with 12% on chromosome, 15% on plasmids and 38% on both. The positive rate of qnr genes was 37% with plasmid location. The positive rates for qnrA, qnrB and qnrS were 6%, 23% and 8%, respectively. The CTX-M ESBLs-positive rate was 34%. For CTX-M-1 ESBLs, 15% were on chromosome, 6% on plasmids and 4% on both; for CTX-M-9 ESBLs, 1% was on chromosome and 7% on plasmid; for CTX-M-25 ESBLs, 3% were on chromosome and 1% on plasmid. Conclusion: Antibiotic resistance genes may be horizontally and vertically disseminated among E. cloacae, which helps multidrug-resistant (MDR) strains of E. cloacae to be successful nosocomial agents.

We numerically study the quantum Hall effect in both monolayer and bilayer black phosphorus (BP) under an external electric field in the presence of both disorder and a strong perpendicular magnetic field based on the tight-binding model. In the monolayer BP case, the quantized Hall conductivity is similar to that of a two-dimensional electron gas (2DEG), but the positions of all the Hall plateaus shift to the left due to the spectral asymmetry, in agreement with the experimental observations. The width of Hall plateau can be increased by applying a bias voltage to the top and bottom layers of the monolayer BP. The longitudinal conductivity exhibits a strong anisotropy that is large along the armchair direction. In the bilayer BP case, the Hall conductivity remains the same quantization rule as in the case of monolayer BP. Under a certain bias voltage, the plateau is markedly absent, and the LLs spectrum shows the appearance of doubly degenerate branches with a zero-energy level. Eventually, the system undergoes a phase transition from 2DEG to Dirac semimetal, which indicates a biased-induced closure of the bulk energy gap. The two central plateaus with are the most robust against disorder scattering. The longitudinal conductivity remains almost constant around zero energy in the presence of moderate disorder strength.

miR-30d has been observed to be significantly down-regulated in human anaplastic thyroid carcinoma (ATC), and is believed to be an important event in thyroid cell transformation. In this study, we found that miR-30d has a critical role in modulating sensitivity of ATC cells to cisplatin, a commonly used chemotherapeutic drug for treatment of this neoplasm. Using a mimic of miR-30d, we demonstrated that miR-30d could negatively regulate the expression of beclin 1, a key autophagy gene, leading to suppression of the cisplatin-activated autophagic response that protects ATC cells from apoptosis. A reporter gene assay demonstrated that the binding sequences of miR-30d in the beclin 1-3′ UTR was the region required for the inhibition of beclin 1 expression by this miRNA. We further showed that inhibition of the beclin 1-mediated autophagy by the miR-30d mimic sensitized ATC cells to cisplatin both in vitro (cell culture) and in vivo (animal xenograft model). These results suggest that dysregulation of miR-30d in ATC cells is responsible for the insensitivity to cisplatin by promoting autophagic survival. Thus, miR-30d may be exploited as a potential target for therapeutic intervention in the treatment of ATC.

The role of flexible membrane flapping wing on aerodynamic field has been investigated in a dynamic fluid‐structure coupling computational framework. Reynolds‐averaged Navier‐Stokes (RANS) solver is used to calculate the aerodynamic force. A newmark solution is used to solve the dynamic structural equations which takes into account of inertial force, aerodynamic force and mechanical acceleration together. An IPS method is used for data exchange between aerodynamic and structural grids. The results show that flexible membrane flapping wing can improve aerodynamic performance comparing with rigid wing, which indicate that the potential aerodynamic performance can be improved by optimal design of the wing structure.

Controlled growth of self-aligned single-walled carbon nanotubes (SWNTs) was realized using optical near-field effects in a laser-assisted chemical vapor deposition (LCVD) process. Electronic devices containing ultrashort suspended SWNT channels were successfully fabricated at relatively low substrate temperatures. According to the numerical simulations using High Frequency Structure Simulator (HFSS), significant local-heating enhancement occurred at electrode tip apexes under laser irradiation, which was about ten times higher than the rest part of the electrodes. Experimental results revealed that the localized heating enhancement at the electrode tip apexes significantly stimulates the growth of SWNTs at a significantly reduced substrate temperature compared with the conventional LCVD process. The near-field enhancement dependence on metallic film thickness and laser polarization was investigated through numerical simulation using HFSS, which provided a guideline for further optimization of maximum near-field enhancement. This technique suggests a viable laser-based strategy for fabricating SWNT-based devices at relatively low substrate temperatures in a precisely controlled manner using the nanoscale optical near-field effects, which paves the way for the mass production of SWNT-based devices using expanded laser beams.

Single-walled carbon nanotubes (SWNT) are regarded as one of the most promising materials for next-generation nano-electronics. However, there are still several challenges limiting its wide applications, including the inability in controlled growth of SWNT connections. In this study, we developed a laser-based in-situ growth approach to simultaneously fabricate SWNT-bridge arrays on a single silicon substrate with precise control. Localized thermal enhancement induced by optical near-field effects and an external electric field enabled the SWNT growth with precise control of growth sites and directions. Furthermore, laser polarization also shows significant influence on the control of growth site for SWNTs. Simultaneous growth of SWNT-bridge arrays in various patterns was achieved. Raman spectroscopy and I-V analysis demonstrated the successful growth of SWNT bridge structures. The laser-based growth method suggests a promising solution for the fabrication of SWNT-based systems in nano-electronics.Single-walled carbon nanotubes (SWNT) are regarded as one of the most promising materials for next-generation nano-electronics. However, there are still several challenges limiting its wide applications, including the inability in controlled growth of SWNT connections. In this study, we developed a laser-based in-situ growth approach to simultaneously fabricate SWNT-bridge arrays on a single silicon substrate with precise control. Localized thermal enhancement induced by optical near-field effects and an external electric field enabled the SWNT growth with precise control of growth sites and directions. Furthermore, laser polarization also shows significant influence on the control of growth site for SWNTs. Simultaneous growth of SWNT-bridge arrays in various patterns was achieved. Raman spectroscopy and I-V analysis demonstrated the successful growth of SWNT bridge structures. The laser-based growth method suggests a promising solution for the fabrication of SWNT-based systems in nano-electronics.

By applying optical near-field effects in a laser-assisted chemical vapor deposition (LCVD) process, self-aligned growth of ultra-short single-walled carbon nanotubes (SWNTs) was realized in a well controlled manner at a relatively low substrate temperature due to the nanoscale heating enhancement induced by the optical near-field effects. Bridge structures containing single suspending SWNT channels were successfully fabricated. Ultra-sharp tip-shaped metallic electrodes were used as optical antennas in localizing and enhancing the optical fields. Numerical simulations using High Frequency Structure Simulator (HFSS) reveal significant enhancement of electrical fields at the metallic electrode tips under laser irradiation, which induces localized heating at the tips. Numerical simulations were carried out to optimize SWNT growth conditions, such as electrode tip sharpness and film thickness, for maximal enhancement of electrical near field and localized heating.

Strongly enhanced optical fields generated by nanoparticles due to Local Surface Plasmonic Resonance (LSPR) enable Surface-Enhanced Raman Spectroscopy (SERS) to perform chemical analysis with extremely high sensitivity. This technique, however, suffers from the disadvantage of low spatial resolution, i.e. 500 nm, due to the optical diffraction limit imposed by conventional optics. On the other hand, a metallic tip irradiated by a laser beam, by which a highly localized and significantly enhanced optical field can be induced, allows Raman spectroscopy to have a spatial resolution of 10 nm. This technique is named as Tip-Enhanced Raman Spectroscopy (TERS). In this study, we took advantages of both SERS and TERS techniques to achieve both high resolution and high sensitivity at the same time. SERS-active silicon substrates with metallic nanostructures were fabricated by Nanosphere Lithography (NSL) technique. Silver (Ag)-coated tungsten tips and gold (Au) tips were prepared by the electrochemical etching method. In order to making use of the evanescent optical field underneath the tip apex, the tip was controlled to position above the substrate surface with a gap distance of 1 nm by a Scanning Tunneling Microscope (STM). The tip was precisely aligned in the region where two adjacent nanostructures (dipole) were located by a nanopositioner. The contrast ratio of Raman intensity of silicon substrates was much higher with the presence of the nanostructures. It is suggested that this extraordinary enhancement is attributed to the interplay between the enhanced optical fields from the nanostructure dipole and from the tip. Numerical simulation was performed to verify the suggestion using the finite-domain-time-difference (FDTD) algorithm based upon the Lorentz-Drude model. A spatial resolution well below 100 nm was confirmed by mapping the metallic nanostructures. This technique has a great potential for single molecule detection, disease diagnosis and therapy control, and nanodevice analysis.Strongly enhanced optical fields generated by nanoparticles due to Local Surface Plasmonic Resonance (LSPR) enable Surface-Enhanced Raman Spectroscopy (SERS) to perform chemical analysis with extremely high sensitivity. This technique, however, suffers from the disadvantage of low spatial resolution, i.e. 500 nm, due to the optical diffraction limit imposed by conventional optics. On the other hand, a metallic tip irradiated by a laser beam, by which a highly localized and significantly enhanced optical field can be induced, allows Raman spectroscopy to have a spatial resolution of 10 nm. This technique is named as Tip-Enhanced Raman Spectroscopy (TERS). In this study, we took advantages of both SERS and TERS techniques to achieve both high resolution and high sensitivity at the same time. SERS-active silicon substrates with metallic nanostructures were fabricated by Nanosphere Lithography (NSL) technique. Silver (Ag)-coated tungsten tips and gold (Au) tips were prepared by the electrochemical etching met...

Well-aligned ZnO nanowires have been synthesized vertically on In0.2Ga0.8N, GaN, and Al0.25Ga0.75N substrates, using a catalyst-free carbon thermal-reduction vapor phase deposition method for the first time. The as-synthesized nanowires are single crystalline wurtzite structure, and have a growth direction of [0001]. Each nanowire has a smooth surface, and uniform diameter along the growth direction. The average diameter and length of these nanowires are 120-150 nm, and 3-10 )m, respectively. We suggest that the growth mechanism follow a self-catalyzing growth model. Excitonic emission peaked around 385 nm dominates the room-temperature photoluminescence spectra of these nanowires. The room-temperature photoluminescence and Raman scattering spectra show that these nanowires have good optical quality with very less structural defects.

To select low-residue herbicide for cultivation of Bupleurum falcatum.Probing the effect of various kinds of herbicide on the budding, growth and yield of B. falcatum both in laboratory and in the fields.Haloxyfop acts slightly on the growth of B. falcarum, but effectively kills weeds of many kinds. Butralin is a good herbicide for Gramineae.

OBJECTIVES: To evaluate the effectiveness of XQ-9302--a purified, precise mixture of 20 Chinese herbs--against infection with human immunodeficiency virus in vitro and in the clinic. DESIGN: In vitro cell culture assay, heavy metal content analysis, and pilot non-randomised clinical trial. SETTING: Drug rehabilitation centre and municipal surveillance centre, Shanghai, China. PATIENTS: Forty-eight patients who had various clinical histories, such as drug abuse, cancer, and infection with human immunodeficiency virus, participated in the clinical study. INTERVENTION: During the clinical trial, multiple 15-day courses of XQ-9302 10.8 g/d were given to participants. MAIN OUTCOME MEASURES: CD4 count, P24 antigen level, level of antibody against human immunodeficiency virus, number of copies per millilitre of human immunodeficiency virus in the plasma (viral load), and any side effects. RESULTS: XQ-9302 protected cultured MT4 cells from infection with human immunodeficiency virus in vitro. Clinical tests showed that the herbal formula relieved the symptoms of acquired immunodeficiency syndrome and enhanced CD4 counts in patients infected by the human immunodeficiency virus. There were no observable side effects, even after taking the drug for several months. In three patients who had acquired immunodeficiency syndrome, treatment with XQ-9302 reduced the magnitude of the viral load by more than 1 log. CONCLUSION: XQ-9302 not only improves the immune function of patients infected with the human immunodeficiency virus, but also interrupts viral replication and slows the progression of the disease without detectable side effects. In addition, the heavy metal content of XQ-9302 is well within safety levels set by the Government of China.

To explore the distribution pattern for serum lipid concentrations among patients with different degrees of chronic renal failure; to study the characteristics of abnormal lipid metabolism for chronic renal failure patients when the disease progress further.No. 255 Hospital of PLA, Tangshan, Hebei, China; No. 281 Hospital of PLA, Beidanhe, Hebei, China; and the General Hospital of Beijing Military Region, Beijing, China.A total of 240 serum/urine samples from 50 healthy volunteers and from 190 patients with different degrees of chronic renal failure, which fall into four groups according to their glomerular filtration rates, were measured for serum levels of triglyceride, lipoprotein(a), lipoprotein(a) cholesterol, total cholesterol, apolipoprotein A1, apolipoprotein B100, low density lipoprotein cholesterol, high density lipoprotein cholesterol, and for urine albumin concentrations; the levels of these criteria were compared between the control group and diseased groups; the mean concentrations of different lipid variables were paired and subjected to linear regression analysis.Glomerular filtration rates were estimated by the iohexol clearance method, in which plasma content of iohexol was measured with high performance liquid chromatography; concentrations of triglyceride, lipoprotein(a), lipoprotein(a) cholesterol, total cholesterol, apolipoprotein A1, apolipoprotein B100, low density lipoprotein cholesterol, high density lipoprotein cholesterol, and albumin were assayed according to standard protocols.Serum levels of triglyceride, lipoprotein(a), lipoprotein(a) cholesterol, total cholesterol, apolipoprotein A1, apolipoprotein B100, low density lipoprotein cholesterol, and urine albumin contents were significantly higher, whereas those of high density lipoprotein cholesterol were lower, in diseased groups than that of the control (p0.05, p0.01). When the disease progressed, concentrations of these criteria increased or decreased further (p0.01, p0.05). Significant correlations were found between a few lipid criteria for their mean concentrations in diseased groups.The study demonstrates a correlation between abnormalities of lipid metabolism and the degrees of kidney insufficiency, and a correlation within certain kinds of lipid criteria in patients with different degrees of renal damage. The results suggest the existence of multi-correlations in vivo in catabolism and metabolism of lipid, lipoprotein, apolipoprotein, and protein in the patients. The exact mechanism responsible for the association and correlation remains to be clarified.

Glutamate is an attractant stimulus to Paramecium tetraurelia. It causes a hyperpolarization of the cell and smooth, relatively fast swimming that is characteristic of hyperpolarizing stimuli. We show here that by 1–30 seconds of stimulation, glutamate increases intracellular cAMP. Interestingly, other attractant stimuli, such as acetate and NH4Cl, that similarly hyperpolarize the cell do not induce an increase in cyclic AMP observable at 30 seconds. In order to determine whether the changes in cyclic AMP could be rapid enough to participate in stimulation as compared to slower processes such as adaptation, rapid kinetic measurements of cyclic AMP were made on whole cells by quenched-flow. We found that, in cells stimulated with glutamate, intracellular cyclic AMP increases by 30 mseconds and peaks at about sevenfold over basal levels by 200 mseconds. Cyclic GMP does not change relative to basal levels over rapid or slower time courses of glutamate stimulation. An antagonist of glutamate, IMP, depolarizes the cells and decreases intracellular cyclic AMP by approx. 50% and slightly increases cyclic GMP. Results of behavioral tests of cells treated with protein kinase inhibitors also suggest that cyclic AMP is part of the signal transduction pathway for glutamate, but not for other attractant stimuli. These studies are the first demonstration of a possible role for cyclic nucleotide second messengers in an attractant chemosensory transduction pathway in Paramecium.

To estimate the stability and reliability of lipoprotein(a) cholesterol measurement, and explore the possibility to evaluate lipoprotein(a) excess in plasma by using lipoprotein(a)-cholesterol assay alternatively to assay lipoprotein(a).Number 255 Hospital of PLA, Tangshan, Hebei, China.A total of 396 plasma samples from 100 healthy people (control), 107 chronic renal failure patients, 114 coronary heart disease patients, and 75 cerebral infarction patients, respectively, were measured for lipoprotein(a) cholesterol and lipoprotein(a) mass; lipoprotein(a) cholesterol and lipoprotein(a) mass levels among control and diseased groups were compared; and lipoprotein(a) cholesterol levels and lipoprotein(a) mass values from the control group were subjected to linear regression analysis.The affinity between oligosaccharide contained in lipoprotein(a) and lectin wheat germ agglutinin to isolate lipoprotein(a) from other lipoproteins; lipoprotein(a) cholesterol and lipoprotein(a) mass detected by total cholesterol kits and enzyme linked immunosorbent assay kits, respectively.Both lipoprotein(a) cholesterol and lipoprotein(a) mass levels of the chronic renal failure, coronary heart disease, and cerebral infarction groups were significantly higher than those of the control (P0.05 or P0.01) whereas no difference was seen among the diseased groups at the 0.05 level. Regression analysis within the control group showed a very high correlation between lipoprotein(a) cholesterol and lipoprotein(a) (r = 0.9932).The results suggest that lipoprotein(a) cholesterol assay may be used in the place of lipoprotein(a) measurement for evaluating lipoprotein(a) excess for chronic renal failure, coronary heart disease, and cerebral infarction patients. Further studies about the mechanism of this association between lipoprotein(a) cholesterol and lipoprotein(a) levels are needed.

The function of the zeta-globin promoter was studied using a series of zeta-globin promoter deletion constructs to drive luciferase expression in transiently transfected human erythroleukemia cells. The promoters were used without enhancers, or with enhancers derived from the beta-globin locus control region and the alpha-globin HS-40 enhancer. When transfected into K562 cells, which express zeta-globin, comparable amounts of activity were obtained from the -557 and -417 zeta-luciferase constructs and the alpha-luciferase constructs when no enhancers or the alpha-globin locus enhancers were used. When the constructs were transfected into OCIM1 cells, which do not express zeta-globin, the zeta-globin promoters were at best 20% as active as the alpha-globin promoters. When sequences from -417 to -207 5' to the zeta-globin mRNA cap site were deleted, up to 95% of the zeta-globin promoter activity was lost in K562 cells. Reinsertion of these sequences into zeta-luciferase constructs missing the -417 to -207 region showed that the sequences lack classical enhancer activity. Point mutation of a GATA-1 site at -230 reduced promoter activity by 37%. Point mutation of a CCACC site at -240 had no effect. Electrophoretic mobility shift assays indicated that the -230 GATA-1 site has a relatively low affinity for GATA-1. These experiments show the presence of a strong positive-acting element, located between -417 and -207 bp 5' to the zeta-globin mRNA cap site, is necessary for high-level promoter activity in K562 cells. This element requires GATA-1 and additional unknown factors for maximal activity.

Self-aligned growth of ultra-short single-walled carbon nanotubes (SWNTs) was realized by utilizing optical near-field effects in a laser-assisted chemical vapor deposition (LCVD) process. By introducing the optical near-field effects, bridge structures containing single suspended SWNT channels were successfully fabricated through the LCVD process at a relatively low substrate temperature. Raman spectroscopy and I-V analyses have been carried out to characterize the SWNT-bridge structures. Numerical simulations using a high-frequency structure simulator revealed that significant enhancement of local heating occurs at metallic electrode tips under laser irradiation; it is about one order of magnitude higher than that in the rest of the electrodes. This technique suggests a novel approach to in situ low-temperature fabrication of SWNT-based devices in a precisely controlled manner, based on the nanoscale heating enhancement induced by the optical near-field effects.

Of 98 counties or cities in Hunan Province, 55 were endemic areas of filariasis. The average microfilaria rate was 5.64% (180,046/3,194,102), and the incidence of advanced filariasis, including elephantiasis and hydrocele was 3.29%. The number of filariasis patients in the whole province was estimated to be 1.63 million, comprising 1.25 million of microfilaremia cases, Culex fatigans and Anopheles hyrcanus sinensis were the major vectors of bancroftian and malayan filariasis respectively in the province. Control strategies concentrated on the elimination of infection source were implemented on the basis of extensive investigations, and the ensuing examination and treatment of filariasis cases in pilot areas prior to the implementation of province-wide filariasis control. Repeated blood examinations and medications for 3-4 times were carried out in hypo-endemic areas of malayan filariasis, whereas mass treatment with hetrazan-medicated salt containing 0.2% to 0.5% DEC was carried out in meso- and hyper-endemic areas of bancroftian filariasis as well as those situated in remote mountainous regions for six months. Subsequent evaluation and clearance checking showed that microfilaria rate of the whole province has already dropped to less than 1%. That filariasis was basically eliminated in Hunan was recognized by the Evaluation Mission Group sent by the Ministry of Public Health in 1986.