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The interaction between biochar and heavy metals in the presence of low molecular weight organic acids is largely unknown, but it is important to understand biochar’s influence on heavy metals immobilizing in the rhizosphere. The impacts of different amounts of biochar (5%) and citric acid, coupled with combinations of biochar and citric acid on the redistribution of cadmium, lead, and zinc among their different geochemical forms, including their bioavailability in metal contaminated soil, were investigated in an incubation experiment. Adding biochar, low concentration of citric acid (2 mmol kg−1 soil), and biochar with a low level of citric acid markedly reduced the acid-soluble and available (CaCl2-extractable) cadmium, lead, and zinc compared to control in which biochar plus low concentration of citric acid proved to be the most effective treatment. These trends were reversed in the case of high concentrations of citric acid (> 5–20 mmol kg−1 soil) and the combined biochar plus high levels of citric acid treatments. With incubation time, biochar in combination with a low concentration of citric acid transformed the largest amounts of acid-soluble and reducible cadmium, lead, and zinc into oxidizable and residual fractions. These results suggested that a low level of citric acid enhanced metals’ immobilization, while higher concentration of citric acid increased their mobilization. The study concluded that biochar with this low level of citric acid did in fact emerge as the best treatment, and can serve as an amendment for metals’ immobilization/redistribution in contaminated soils.

A time-dependent global model is developed for deep oscillation magnetron sputtering (DOMS) with a Cr target to characterize the plasma using the working Ar gas at a pressure of 0.8 Pa. An input of the global model is the target voltage and current waveforms at charging voltages from 260 to 400 V. The plasma densities vary synchronously with the oscillations of target power. During the on-time of a micropulse, the gas atoms are ionized first to ignite the plasma and subsequently the metal ions follow to sustain the discharge. During the off-time, the gas ions dominate the afterglow. The DOMS possesses a characteristic of alternating gas/metal discharge in the time domain. The peak values of plasma densities increase linearly with charging voltages, which is mainly attributed to the higher Cr+ ion density. The discharge transits from gas dominated to metal dominated at high charging voltage. The working gas rarefaction in DOMS discharge is enhanced at higher charging voltages. At charging voltages higher than 360 V, the metal self-sputtering comes into the runaway regime temporarily as indicated by the self-sputtering parameters exceeding unity, generating the dense and metal-rich plasma. The metal self-sputtering is promoted by gas rarefaction. The electrons tend to ionize the metal atoms after the gas atoms are depleted. The decreased grain size and elevated nano-hardness of the Cr thin films are explained by structure transition from zone I to zone T due to the efficient metal ion bombardment to the growing thin films as the charging voltage increases.

To investigate the ability of a multidisciplinary approach that combines multimodal neuroimaging with video-electroencephalography (v-EEG) to predict post-surgical outcomes in patients with intractable epilepsy, and explore prognostic predictors for these patients.Fifty-eight patients with intractable epilepsy who underwent surgery between March 2016 and October 2019 were reviewed retrospectively. Demographic, clinical, v-EEG, neuroimaging, surgical, and regular follow-up seizure outcome data were collected. Forty-six patients with a follow-up of at least 12 months were graded by Engel scores. Univariate and multivariate analyses were applied to explore prognostic factors that could predict post-surgical seizure outcomes.Of the 58 patients, 28 were males. The median age was 27 years, the median age at first seizure was 11 years, and the median duration of seizures was 10 years. The Kaplan-Meier log-rank test showed that regardless of whether the follow-up duration was considered, epilepsy type, v-EEG, PET/CT, image post-processing methods, and a multidisciplinary approach that combined multimodal imaging with v-EEG were all correlated with seizure outcomes. Multivariate analysis found that the multidisciplinary approach was an independent predictor of post-surgical outcomes in patients with intractable epilepsy (hazard ratio = 11.400, 95% confidence interval = 2.249-57.787, p=0.003).The present study showed that the multidisciplinary approach could provide independent prognostic information for patients with intractable epilepsy undergoing surgery. This approach has strong potential for the easier selection of patients to undergo surgical treatment and accurate prognostication.

Fluorescent N-doped carbon dots (CN-dots) covalently functionalized with carboxylatopillar[5]arene (CP[5]), namely CCDs, have been prepared the first time. Compared with CN-dots without pillarene units, the newly constructed fluorescent CCDs could recognize Fe3+ with high selectivity. Therefore, such CCDs can potentially serve as a promising chemical sensor for Fe3+ ions.

The aim of this study was to explore the correlation between rs8069115, rs41289087, and rs11079042 polymorphisms of the signal transducer and activator of transcription 3 (STAT3) gene and chronic obstructive pulmonary disease (COPD).A total of 200 patients diagnosed with COPD were enrolled in the disease group. Meanwhile, 200 normal subjects were selected as the control group. Peripheral blood was collected from subjects in the disease group and control group. Subsequently, nucleated cells were isolated for determination of STAT3 gene polymorphisms. Quantitative Polymerase Chain Reaction (qPCR) was utilized to detect the expression level of STAT3. Samples from 12 patients with differences in STAT3 haplotypes and 12 cases with no difference were collected and treated with transcriptome sequencing to analyze pathways enriched with differentially expressed genes.There were statistically significant differences in allele distributions at rs8069115 between the disease group and control group (p=0.000), and the allele frequency of G was higher in disease group. Genotype distributions of rs8069115 (p=0.000) and rs41289087 (p=0.000) of the STAT3 gene in disease group were significantly different in comparison with the control group. The frequency of rs8069115 GG genotype was remarkably higher, while the frequency of rs41289087 TG genotype was lower in the disease group (p0.05). In addition, compared with the control group, the distributions of the dominant model (p=0.002) and recessive model (p=0.004) of rs8069115 of the STAT3 gene were markedly different in the disease group. A significantly higher frequency of dominant model GG+GA and lower frequency of recessive model GA+AA were observed at rs8069115 in the disease group (p0.05). Moreover, the haplotype distributions of AGC (p=0.002), ATC (p=0.001), GTA (p=0.010), and GTC (p=0.035) at rs8069115, rs41289087, and rs11079042 were different between the disease group and control group. Besides, rs8069115 locus and rs11079042 locus were linked to each other (D'=0.523). There was a remarkable association between rs11079042 polymorphism of the STAT3 gene and gene expression (p0.05). STAT3 was highly expressed in patients with genotype CC (p0.05). Furthermore, changes in transcriptome levels among different haplotype populations (haplotype with different distributions vs. haplotype with no difference in distribution) were analyzed. The results demonstrated that multiple pathways, such as ECM-receptor interactions, cell cycle checkpoints, and protein processing were notably enriched (p0.05).According to our results, we confirmed that the polymorphisms (rs8069115, rs41289087, and rs11079042) of STAT3 gene are noticeably correlated with the occurrence and progression of COPD.

Multifunctional supramolecular nanomaterials capable of targeted and multimodal therapy hold great potential to improve the efficiency of cancer therapeutics. Herein, we report a proof-of-concept nanoplatform for effective chemophotothermal therapy via the integration of folic acid-based active targeting and supramolecular nanovalves-based passive targeting. Inspired by facile surface engineering and designable layer-by-layer assembly concept, we design and synthesize PPy@UiO-66@WP6@PEI-Fa nanoparticles (PUWPFa NPs) to achieve efficient synergistic chemophotothermal therapy, taking advantage of the desirable photothermal conversion capability of polypyrrole nanoparticles (PPy NPs) and high drug-loading capacity of hybrid scaffolds. Significantly, pillararene-based pseudorotaxanes as pH/temperature dual-responsive nanovalves allow targeted drug delivery in pathological environment with sustained release over 4 days, which is complementary to photothermal therapy, and folic acid-conjugated polyethyleneimine (PEI-Fa) at the outmost layer through electrostatic interactions is able to enhance tumor-targeting and therapeutic efficiency. Such PUWPFa NPs showed efficient synergistic chemophotothermal therapy of cervical cancer both in vitro and in vivo. The present strategy offers not only the distinctly targeted drug delivery and release, but also excellent tumor inhibition efficacy of simultaneous chemophotothermal therapy, opening a new avenue for effective cancer treatment.

The double tube structure is simulated, R32 in the inner helical corrugated tubes with vertical grooves is heated by the water flowing in the outer tube to make it boil. The influence of pipe diameter and number of vertical grooves on the performance of double tube is analyzed. The evaporation temperature of the refrigerant is 283K. The temperatures of inlet refrigerant and inlet water are 280K and 320K, respectively. The flow velocity of inlet refrigerant and inlet water are 1m/s and 5m/s, respectively. The simulation results show that, compared with the smooth pipe, when the inner pipe diameter is 3, 4, 5, 6, 7mm, the surface heat transfer coefficients of the double tube have been increased by 160%, 150%, 147%, 138%, and 130%, respective. when PEC=1.691, the performance of the inner helical corrugated tube is the best, whose inner pipe diameter is 3 mm, outer pipe diameter is 6.2 mm, number of vertical grooves is 10.

Magnetite sorbents (MS) have been widely employed for water purification; however, adsorption capacity loss frequently occurs during the formation of magnetite sorbents. In this study, we report the preparation of S-doped magnetite hollow spheres (S-doped MHS) used for the removal of UO22+ with a large adsorption capacity of 450.0 mg U per g, higher than that of pure Fe3O4. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and a vibrating sample magnetometer (VSM) were used to determine the effectiveness of the synthesis of S-doped MHS. The S-doped MHS was investigated for the adsorption of uranium(vi) from an aqueous solution. In addition, the adsorption process fits the Freundlich isotherm model and pseudo-second-order rate equation perfectly. The affinity and selectivity of S-doped MHS for uranium(vi) is significantly high. S-doped MHS can be easily separated using an external magnetic field. Moreover, S-doped MHS can be used for the adsorption of other heavy metal ions, which indicates their promising potential applications as adsorbents in aqueous solutions.

OBJECTIVE: Deep learning models, including recurrent neural network (RNN) and gated recurrent unit (GRU), were used to construct the clinical prognostic prediction models for peritoneal dialysis (PD) patients based on routine clinical data. The performance of the RNN and GRU were compared with logistic regression (LR), which is commonly used in medical researches. The possible underlining clinical implications based on the result from the GRU model were also investigated. METHODS: We used the clinical data from the PD center of Peking University Third Hospital as the data source. Both the baseline data at the beginning of dialysis, and the follow-up and prognostic data of the patients were used by the RNN and GRU prediction models. The hyper-parameters were tuned based on the 10-fold cross-validation. The risk prediction performance of each model was evaluated via area under the receiver ope-ration characteristic curve (AUROC), recall rate and F1-score on the testset. RESULTS: A total of 656 patients with the 261 occurrences of death were included in the experiment. The total number of all diagnostic records were 13 091. The results on the testset showed that the AUROC of the LR model, RNN mo-del, and GRU model was 0.701 4, 0.786 0, and 0.814 7, respectively. The predictive performances of the GRU and RNN models were significantly better than that of the LR model. The performances of the GRU and RNN models assessed by recall rate and F1-score were also significantly better than that of the LR model, in which the GRU model reached the best performance. In addition, the recall rates were different among different causes of death or by different prediction time windows. CONCLUSION: The recurrent neural network model, especially the GRU model, is more effective in predicting PD patients’ prognosis as compared with the LR model. This new model may be helpful for clinicians to provide timely intervention, thus improving the quality of care of PD.

Melting experiments in a vertical square enclosure are undertaken with a solid–liquid phase-change material ( n -octadecane) dispersed with nanoparticles (Al 2 O 3 ) as the nano-phase-change-material (nano-PCM). The enclosure has a cross-section dimension of 25 by 25 mm and it was 60 mm long. The vertical side walls were differentially heated isothermally while the remaining side walls were thermally insulated. The effect of dispersing nanoparticles in the base phase change material (PCM) on the melting heat transfer characteristics in the enclosure is examined for the relevant parameters in the following ranges: the mass particle fraction of nanoparticles, ω p = 0, 5, 10 wt.%; the Rayleigh number, Ra f = 1.71 × 10 6 –5.67 × 10 7 ; the Stefan number, Ste f = 0.037–0.108; and the subcooling parameter, Sb = 0.042–0.537. The surface-averaged heat transfer results obtained during the melting experiments indicate that natural convection heat transfer into the melted region of the enclosure tends to degrade markedly with increasing mass fraction of nanoparticles dispersed in the nano-PCM, when compared with that of the base PCM.

Centimeter-sized Te:GaSe (≤10 mass%) ingots have been grown by the vertical Bridgman technique and studied to reveal the potentials for phase matching and frequency conversion. Less than 5 mass% Te-doped crystals show the hexagonal structure like e-GaSe. Te:GaSe (≤2 mass%) crystals were suitable for non-linear applications. The optimal Te-doping level between 0.1 and 0.5 mass% has been clearly observed in CO2 laser SHG experiment. The CO2 laser SHG efficiency in Te:GaSe (0.1–0.5 mass%) is ∼20 % higher than that of GaSe due to better optical quality. Phase matching conditions in Te-doped crystals have been shown to be identical with those of GaSe.

Phase matching for the second harmonic generation in GaSe nonlinear optical crystals at room temperature is investigated in details. The most reliable system of dispersion equations is identified by a comparison of the modeling results for all known systems of dispersion equations and the available experimental data on phase matching for the second harmonic generation.

Riemerella anatipestifer (RA) is the causative agent of septicemic and exudative disease for a variety of bird species. Although RA had been isolated from chickens, whether can bring damages to them is not unrevealed yet. In this study, we report a flock of SanHuang chickens infected by RA with 15% morbidity and less than 8% mortality. The infection is further substantiated by case duplicate. The tested chickens demonstrate typical signs of pericarditis, air sacculitis and perihepatitis that are completely consistent with the field outbreak. The results suggest that RA is pathogenic to SanHuang chickens, which can then be theoretically and practicably incorporated into its infection spectrum.

An intelligent theranostic nanoplatform based on nanovalve operated metal-organic framework (MOF) core-shell hybrids, incorporating tumorous microenvironment-triggered drug release, magnetic resonance imaging (MRI) guidance, sustained release, and effective chemotherapy in one pot is reported. The core-shell hybrids are constructed by an in situ growth method, in which Fe3 O4 particles with superior abilities of MRI and magnetic separation form the core and UiO-66 MOF with high loading capacity compose the shell, and then are surface-installed with pillararene-based pseudorotaxanes as tightness-adjustable nanovalves. This strategy endows the system with the ability of targeted, multistimuli responsive drug release in response to pH changes, temperature variations, and competitive agents. Water-soluble carboxylatopillar[6]arene system achieved sustained drug release over 7 days due to stronger host-guest binding, suggesting that the nanovalve tightness further reinforces the desirable release of anticancer agent over a prolonged time at the lesion site.

The simultaneous synthesis and densification of MoSi2 starting from elemental Mo and Si was carried out through a process of field-activated pressure-assisted combustion synthesis (FAPACS). After heating up to 922°C, the synthesis reaction occurs in the mode of thermal explosion but is ceased subsequently due to a sudden shock. The product consists of MoSi2, residual Mo and amorphous Si with precipitation of very small MoSi2 primary crystals containing. There is no transition phase layer between Mo and MoSi2 as well as Si and MoSi2. This indicates that metallic Mo reacts with molten Si directly forming MoSi2 in the FAPACS process, without any intermediate reaction steps involved. The formation of MoSi2 occurs via dissolution of Mo into Si melt followed by MoSi2 precipitation from the melt.

The combustion synthesis of Mo5Si3 was carried out in a chemical furnace using 5Ti + 3Si mixtures as a chemical fuel. The synthesized single phase Mo5Si3 exhibited a spatial network microstructure and angular texture of crystals. The chemical composition and crystal morphology of intermediate phases suggest that the formation of Mo5Si3 occurs via dissolution of Mo in the Si melt followed by reactive diffusion in the supersaturated “liquid Si-Mo melt-solid Mo” system.

A relatively simple efficient electrooptically Q-switched Er:Cr:YSGG laser oscillator-amplifier system in a line has been demonstrated. A Glan-Taylor prism and a cubic LiNbO3 crystal are used as the polarizer and modulator, respectively. Using the line scheme, one can adjust the system elements easily and achieve a good Q-switched-to-free-running pulse energy ratio of 75% and an energy amplification coefficient of 1.8. As short as 80 ns of the leading edge of a stable single pulse and 132 ns in FWHM with an energy of 24.5 mJ are generated. We also investigate the effects of the pump energy and the delay time on the postlasing, the stable single-pulse operation, the prelasing, the laser buildup time, and the Q-switched pulse width. The laser system demonstrated can be used for the effective ablation of soft and hard tissues.

The technique of Second-Harmonic Generation (SHG) of CO2 laser for carbon monoxide concentration detection is investigated in this paper. A simple mechanical Q-switched CO2 laser is used in our experiment, which works at 9.586 μm. The nonlinear optical crystal used for frequency doubling is ZnGeP2. Different CO concentration detections are performed and 100ppm detectable sensitivity is obtained.

Two types of electro-optically Q-switched Er:Cr:YSGG lasers with different polarizing mechanisms have been operated. For the one Q-switching and polarizing are realized with only a LiNbO3 crystal with both ends cut at Brewster's angle and for the other they are achieved by a cubic LiNbO3 crystal and a Glan-Taylor prism, respectively. The two schemes are compared with regard to both the mechanical and laser Q-switched properties.

A capillary electrophoretic (CE) method with β-cyclodextrin (CD) as modifier has been developed to enable separation, for the first time, of bioactive pentacyclic triterpene acids from the fruits of Rubus chingii. The effects of conditions such as the concentration of the running buffer, amounts of added β-cyclodextrin and organic modifier, applied voltage, and column temperature were systematically investigated to optimize the separation conditions. Baseline separation was achieved for the seven triterpenes by use of background electrolyte consisting of 200 mmol L−1 disodium tetraborate, 15 mmol L−1 β-cyclodextrin, and 12.5% (v/v) methanol. Binding constants between β-cyclodextrin and the triterpenes in the capillary electrophoresis buffer were calculated from the order of migration to elucidate the separation mechanism. The amounts of the triterpenes in the fruits of R. chingii were also determined by use of the method after a relatively simple extraction procedure.

We propose a novel scheme for light amplification and gain equalization by quantum interference. We find that the laser amplification can be observed at three specific probe frequencies in a four-level system. Furthermore, we show that three gain peaks can be combined into one to obtain gain equalization.

We study the effects of quantum interference from spontaneous emission on the dispersion-absorption properties in a three-level V-type atomic system with two near-degenerate excited levels. We found that due to the quantum interference between two spontaneous decay channels, large index of refraction without absorption always can be obtained just by choosing proper values of the relative phase between the two applied fields.

Phase synchronization in coupled chaotic oscillators, a situation where the phase differences of the oscillators are bounded while their amplitudes remain uncorrelated, has been shown to occur for chaotic attractors having a proper structure of rotation in phase space. As applications of phase synchronization become popular, it is important to understand its limit. Here we show that phase synchronization in the above sense cannot occur for the general class of coupled Lorenz type of chaotic oscillators. For such a system, intermittent synchronization between the dynamical variables sets in as soon as an originally null Lyapunov exponent becomes negative.

A five-level system to control the wavelength of the in-line amplifier by the quantum interference is proposed. It is found that the gains of the first and the second probe can be adjusted by changing the coherent field and the incoherent pumping. The new scheme may find its application in optical switch and optical communications.

Centimeter-sized Er-doped single crystals were grown from the melts GaSe:Er(0.025, 0.1, 0.5, 1 and 2 at%) by modified vertical Bridgman technology. Real Er content is ascertained as 0.009, 0.019, 0.033, 0.042 and 0.048 at%, respectively. Solubility of Er in GaSe does not exceed 5 x 10(-4). Optimal doping of 0.033 at% of Er was established from SHG experiment. Improved optical quality is identified as a reason of increased nonlinearity for about 24% to that in pure GaSe. New Raman scattering band is found at 2900 cm(-1) that properly related to F-4(9/2)-> I-4(9/2) transition of Er3+ ion. (C) 2013 Elsevier B.V. All rights reserved.

We present an experimental demonstration of electromagnetically induced two-photon transparency (EITT) in room temperature rubidium vapor. The 8S(1/2) to 5P(1/2) fluorescence is used to monitor the 5S(1/2)(F = 3)to 8S(1/2)(F = 3) two-photon absorption near resonance with the intermediate state 5P(3/2). A controlling pump laser beam is employed to coherently couple the 5P(3/2) and 5D(5/2) states, thus producing tw dressed intermediate states which give rise to destructive interference in the two-photon transition. An induced two-photon transparency of about 80% has been obtained at resonance; our experimental findings are in good agreement with the general theory of Agarwal et al. (Phys. Rev. Lett., 77 (1996) 1039), when the appropriate spectroscopic parameters are used.

Packed column supercritical fluid chromatography (SFC) is capable of highly efficient separations of drug-like molecules with les solvent consumption than HPLC. However, solute peaks in SFC are susceptible to broadening and distortion due to mismatch between the elution strength and viscosity of the injection solvent and the SFC mobile phase. The magnitude of solvent-induced band broadening increases as the elution strength and viscosity of the sample and mobile phase become more dissimilar and varies with the type of stationary phase used and the nature of the solute injected. A number of researchers have coupled supercritical fluid extraction with supercritical fluid chromatography in an attempt to remove solvent from injected samples, and thereby reduce peak broadening and distortion during SFC chromatography. While solventless injection is effective in overcoming solvent-induced band broadening in SFC, there have been few reports dealing with the optimization of the solvent removal process of this technique. In this work, we describe the influence of temperature, purge time, purging gas flow rate, stationary phase used in the sample precolumn, and injection solvent composition on solvent elimination and solute recovery.

Wave propagation in granular materials is numerically studied using discrete element simulation. Primary interest is concerned with linking material microstructure with wave propagational behaviors for materials composed of elliptical particles. The discrete element (DEM) scheme uses a nonlinear hysteretic contact law, which accounts for differences related to the radius of curvature at the interparticle point of contact. Modeling results yield information on wave speed and amplitude attenuation on two-dimensional, meso-domain model systems of both regular and random assemblies. Particulate models were numerically generated using a biasing scheme whereby partial control of particular fabric measures could be achieved. Three specific fabric measures which were used to characterize the granular material models include branch, contact normal and orientation vectors. DEM simulation results indicated that wave speed and attenuation generally correlated with vector distributions of these fabric variables. A power law relation was proposed between wave speed/attenuation and three averaged projected fabric variables based on orientation, contact normal and branch vectors. Predictions from this specific relation correlated reasonably well with DEM results. (A) For the covering abstract see IRRD 892142.

According to the concept of pollination syndromes, floral traits reflect specialisation to a particular pollinator or set of pollinators. However, the reproductive biology of endemic, and often specialised, plants may require increased attention as climate change accelerates worldwide. Species of Roscoea endemic to the Himalayan region have striking orchid-like flowers with long corolla tubes, suggesting pollination by long-tongued insects. Until now, the reproductive biology of species of Roscoea has been poorly documented. We investigated the floral biology, breeding system and pollination ecology of R. cautleoides and R. humeana, from Hengduan Mountains, a global biodiversity hotspot in southwest China. We also tested whether floral longevity increases pollination success. Pollination experiments showed that the two species were self-compatible and depended on insects for fruit production. Over several flowering seasons we did not observe any potential pollinators with long tongues that matched the corolla tube visiting flowers in centres of distribution. The principal pollinators observed were pollen-collecting generalist bees, with low visitation frequencies. In general, members of the ginger family are characterised by short-lived (usually 1 day) flowers, but flowers of R. cautleoides and R. humeana last 8 and 6 days, respectively. Removing stigmas decreased fruit set in both study populations. Our results suggest that the original pollinators may have been long-tongued insects that are now absent from the Chinese Himalayas because habitats have responded to climate change. However, long-lived and self-compatible flowers, coupled with the presence of generalist pollinators, are traits that have allowed these gingers to reproduce and continue to persist in the alpine habitats.

In the title compound, [Ni(C(8)H(5)Cl(2)N(3)OS)(C(12)H(8)N(2))(CH(3)OH)], the Ni(II) atom is octa-hedrally coordinated by one N, one O and one S atom from a 3,5-dichloro-2-oxidobenzaldehyde thio-semicarbazonate ligand, another O atom from methanol and another two N atoms from 1,10-phenanthroline. The crystal structure is constructed by N-H⋯Cl, N-H⋯N, C-H⋯S and O-H⋯S hydrogen bonds.

Inhomogeneously broadened doped solids supporting electromagnetically induced transparency are viable materials where optically tunable photonic band gaps may be observed and results are shown for Pr:YSO and nitrogen-vacancy color center materials. Such crystals, when coherently driven by a strong pump beam in a suitably designed standing wave configuration, exhibit a tunable stop-band with rather different values of the reflectivity. The different propagating behavior is investigated and characterized for a weak probe across the gap region of the two materials.

To analyze the genetic relationship of Dendrobium and design a specific primer to differentiate Dendrobium candidum effectively.Random amplified polymorphic DNA (RAPD) technique was used to analyze the genetic relationships of 26 species of Dendrobium and one species of Ephemerantha. Dendrogram was constructed by UPGMA. According to the sequence of DNA fragment selected, Sangon 18 primer had been extended from 3' extreme to 20 bp in order to form a specific primer.This primer can be used to distinguish Dendrobium candidum from other Dendrobium effectively. Such a technique provides a new way for the identification of Chinese traditional medicines.

Objective. To test the validity of an animal model in selecting anti-motion sickness drugs, and compare the effects of two drugs. Method. Anti-motion sickness effects of two drugs (Cyclizine and Scopolamin-d-amphetamin compound) were observed in rats with motion sickness (MS) induced by rotatory stimulation and the amount of Kaolin ate by rats was taken as an evaluation criterion. Result. The consumption of Kaolin by the rats decreased significantly after administration of both drugs, and the effect of Scopolamin-d-amphetamin compound was better than those of Cyclizine under the same condition. Conclusion. It suggests that the rat model of motion sickness is practical and useful in studying anti-motion sickness drugs.

To observe pharmacokinetic changes under simulated weightlessness in relevant to body flood flow changes.Gentamicin was selected as probe drug in the present study, and rabbits exposed to Head-Down Tilt (HDT, -20 degrees) immobilization were selected as simulated weightlessness animal model. Seven rabbits were treated inf. with 3 mg/kg of gentamicin sulfate pre-HDT and 7 d after HDT. Gentamicin blood samples within 4 h after administration were analyzed by TDxFLx.The distribution of gentamicin postponed significantly: a significant decrease in alpha from (0.1838 +/- 0.1076) min-1 before HDT to (0.0591 +/- 0.0334) min-1 after HDT; a significant increase in t1/2 alpha from (5.30 +/- 3.55) min to (15.04 +/- 7.49) min; a significant decrease in k12 from (0.1025 +/- 0.0721) min-1 to (0.0181 +/- 0.0161) min-1, a increase trend in V(C) and V(D). After HDT, CL(S) of gentamicin increased from (2.2 +/- 0.5) ml min-1 kg-1 to (2.7 +/- 0.3) ml min-1 kg-1.Simulated weightlessness might induce pharmacokinetic changes.

Objective. To observe the improved effect of syndromes of blood stasis by taking Chinese medicine during bed-rest simulated weightlessness. Method. Ten subjects were randomly divided into two groups: Chinese medicine group and control group. Both of them were exposed to HDBR -6 degrees for a week. The Chinese medicine group took Chinese medicine during the bed rest, and the control group took sugar water. Result. Syndromes of blood stasis of Chinese medicine group had a significant relief. And some physiological parameters, such as blood pressure, pulse graph, and amount of urine, maintained the level of pre-bed rest. While the control group was more severe than the Chinese medicine group in syndromes of blood stasis. Conclusion. Chinese medicine can be a measure in preventing the effect of weightlessness.

Objective. To observe the counteracting effect of a Chinese herb-compound on "insufficiency of spleen qi" induced by simulated weightlessness. Methods. Animal and human experiment were carried out to the Chinese herb-compound (Dangshen, Baizhu, Fuling etc). Result. This compound protected the tail suspended rats from atrophy of spleen, thymus, soleus and gastrocnemius muscles, prevented excessive decrease of body weight effectively; at the same time it relieved the symptoms of the subjects greatly. Conclusion. It demonstrated that the compound decreased the "insufficiency of spleen qi" of both animals and human subjects.

The impact of fs and ns pulses on indium and sulfur doped gallium selenide crystals with four and five different doping concentrations, respectively, has been studied in comparison with that of undoped GaSe. The inconsistence of the visual criterion of the damage threshold determination has been demonstrated. The multiphoton absorption and thermal effect have been identified as key factors limiting fs and ns pulse pump intensities, respectively. High advantages in the limit pump intensity as up to 50% for optimally indium-doped crystal and up to 4.5 times for optimally sulfur-doped crystal have been demonstrated under fs pulses expose.