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Dormancy is an adaptation mechanism of plants to environmental stress. Myricaria laxiflora undergoes a long period of flooding stress every year. In order to determine whether this species escapes flooding stress through dormancy, young branches and leaves were collected at different time points before the onset of flooding, and changes in the content/activity of hormones/enzymes that are closely involved in plant growth were monitored. The inducing environmental factors of summer dormancy were identified. The branches and leaves of M. laxiflora showed the following trends as summer flooding approached: (1) gradual increase in the abscisic acid content; (2) gradual decrease in the gibberellin and cytokinin contents; and (3) a continuous decrease in the activities of malate dehydrogenase (MDH), ribulose diphosphate carboxylase (RuBisCo), and glycolate oxidase (GLO). Pearson correlation analysis revealed (1) daylight duration was highly correlated with the hormone content and enzyme activity; (2) the daily mean air temperature (DMAT) was significantly correlated with the cytokinin content. These findings suggest that daylight duration was the main environmental factor leading to changes in the phytohormone content and enzyme activity as well as leading to summer dormancy. M. laxiflora undergoes dormancy before the onset of summer flooding to escape summer flooding stress. Our data indicate that summer flooding does not impede the survival and growth of M. laxiflora.

Objective To prepare neutralizing monoclonal antibodies (mAbs) against envelope protein domain III of the four dengue virus serotypes (DENV-EDIII) and identify its specificity. Methods BALB/c mice were immunized with recombinant EDIII protein (rDENV-EDIII) of the four DENV serotypes. Hybridoma cells secreting DENV-EDIII antibodies were screened by indirect ELISA. The specificity of positive hybridoma cells were further tested by indirect immunofluorescence assay (IFA). The neutralizing activities of DENV-EDIII mAbs in vitro were determined by the enzyme-linked immunospot microneutralization test (ELISPOT-MNT). Results 6 mAbs specific for the EDIII of the four DENV serotypes and 11 mAbs specific for only one serotype of DENV-EDIII protein were obtained, of which one monoclonal antibody had a balanced strong neutralizing activity against the four DENV serotypes in vitro, and its 50% inhibitory concentrations (IC

The resistive switching (RS) mechanism of hybrid organic-inorganic perovskites has not been clearly understood until now. A switchable diode-like RS behavior in MAPbBr3 single crystals using Au (or Pt) symmetric electrodes is reported. Both the high resistance state (HRS) and low resistance state (LRS) are electrode-area dependent and light responsive. We propose an electric-field-driven inner p-n junction accompanied by a trap-controlled space-charge-limited conduction (SCLC) conduction mechanism to explain this switchable diode-like RS behavior in MAPbBr3 single crystals.

Dielectric barrier discharge (DBD) can produce a large amount of active particles and has many applications in the industry. In order to study the effect of different rising edges, falling edges, and waveform voltages on DBD, a novel all-solid-state bipolar multilevel high-voltage pulse generator is proposed. Compared with other topologies, the proposed system can achieve more levels of waveforms with fewer switches. This article introduces the structure and working principle of the system in detail. Through PSPICE simulation, it is found that the capacitance of the switch junction will generate prepulse for the output. To solve this problem, an improved control strategy is proposed. Finally, a nine-level test prototype is built, which can work steadily under different loads. Meanwhile, different types of output waveforms are allowed to be generated when the control is adjusted. Finally, the main circuit uses 20 power switches and nine energy storage capacitors and this system can achieve a maximum output voltage of ±4 kV, adjustable frequency, and a total of 19 level voltage output (including 0 level).

Significant physical and optical properties have been proved in MAPbX3 (X = Cl, Br, I) perovskite single crystals, especially for the mixing halide component. Herein, to investigate the fundamental effects on optical and electrical properties after the incorporation of Cl into MAPbBr3, we demonstrated a facile solution growth for preparing a series of high-quality MAPb(Br1−xClx)3 single crystals. A general principles regarding the modulation of precursor solution and the optimization of growth temperature were concluded. The resistive switching behavior and ohmic linear I-V characteristics were observed in different crystals. It was found that the mixed halide perovskites show significant improved bulk resistivity, carrier concentration and mobility, relative with the pure halide perovskites.

In this Letter, we show, both theoretically and experimentally by the molecule dynamics calculation and in-situ Raman scatting, respectively, that the polar molecules in CH3NH3PbI3 perovskite, upon bending, would form a stable molecule alignment, suggesting that hybrid organic–inorganic perovskites are promising candidates for semiconducting ferroelectric materials. Our research provides an alternative paradigm for determining of polarization shifting in ferroelectrics, especially those with large electrical conductivity.

Dengue virus (DENV) envelope [E] protein is the major surface protein of the virions that indued neutralizing antibodies. The domain III of envelope protein (EDIII) is an immunogenic region that holds potential for the development of vaccines; however, the epitopes of DENV EDIII, especially neutralizing B-cell linear epitopes, have not been comprehensively mapped. We mapped neutralizing B-cell linear epitopes on DENV-1 EDIII using 27 monoclonal antibodies against DENV-1 EDIII proteins from mice immunized with the DENV-1 EDIII. Epitope recognition analysis was performed using two set of sequential overlapping peptides (16m and 12m) that spanned the entire EDIII protein from DENV-1, respectively. This strategy identified a DENV-1 type- specific and a group-specific neutralizing epitope, which were highly conserved among isolates of DENV-1 and the four DENV serotypes and located at two regions from DENV-1 E, namely amino acid residues 309-320 and 381-392(aa 309-320 and 381-392), respectively. aa310 -319(310KEVAETQHGT319)was similar among the four DENV serotypes and contact residues on aa 309 -320 from E protein were defined and found that substitution of residues E309 , V312, A313 and V320 in DENV-2, -3, -4 isolates were antigenically silent. We also identified a DENV-1 type-specific strain-restricted neutralizing epitope, which was located at the region from DENV-1 E, namely amino acid residues 329-348 . These novel type- and group-specific B-cell epitopes of DENV EDIII may aid help us elucidate the dengue pathogenesis and accelerate vaccine design.

To investigate the characteristics and dynamic changes of serum neutralizing antibody response in patients with primary infection of dengue virus type 1 (DENV-1).Serum samples were obtained from the same patients with primary infection of DENV-1 within 2 weeks after symptom onset in 2006 and in 2010. A group-specific DENV NS1 capture ELISA-based micro-neutralizing test (ELISA-MNT) capable of detecting neutralizing antibodies against all the 4 serotypes of DENV was used to test the neutralizing antibody titers against DENV in the serum samples. The neutralizing antibody titers against a standard strain and 2 clinically isolated strains of DENV-1 were detected in serum samples collected in 2010.Cross-reactive neutralizing antibody response against all the 4 serotypes of DENV was found in both of the serum samples collected in 2006 and 2010, but the samples collected in 2006 showed stronger cross-reactive neutralizing antibody responses. The neutralizing antibody against DENV-2, rather than the anticipated DENV-1 antibody, had the highest titer in the samples collected in 2006, whereas the antibody against homologous DENV-1 had the highest titer in the samples obtained in 2010. The neutralizing antibody titers against the homologous DENV-1 was significantly higher in samples collected in 2010 (U=86.500, P=0.000), which also demonstrated significantly different neutralizing antibody titers against the 3 different strains of DENV-1 (Χ(2)=12.123, P=0.002).The production of cross-reactive neutralizing antibodies between the 4 serotypes of DENV is a characteristic of DENV infection, particularly during early infection, but only the homologous neutralizing antibody increases obviously over time. The titers of the neutralizing antibodies against different strains, even of the same serotype, may differ distinctly.

To investigate the inhibitory effect of lentiviral vector-mediated short hairpin RNA targeting survivin (LV-survivin shRNA) on angiogenesis and growth of endometriosis-like lesions in chick en embryo chorioallantoic membrane.Eutopic endometrium from women with endometriosis was transplanted onto the non-vascular region of (CAM), where LV-survivin shRNA was delivered subsequently. The angiogenesis and the growth of endometriosis-like lesions in the CAM model were evaluated.The angiogenesis and formation of endometriosis-like lesions were significantly suppressed in the CAM model by treatment with LV-survivin shRNA in comparison with those in the untreated CAM models and models treated with empty LV or DMEM (P0.001). LV-survivin shRNA also caused a significantly higher cell apoptotic rate in the endometriosis-like lesions than the other treatments (P0.001) and induced necrosis in the lesions.LV-survivin shRNA can effectively inhibit angiogenesis induced by the eutopic endometrium and markedly suppress the formation of endometriosis-like lesions in the CAM model.

DalText, a prototype information retrieval system has been developed that permits the user to select access methods based on the task at hand. The system integrates multiple access techniques to such textual data as those generated through word processing packages, newsgroups, e-mail, etc., that are not maintained in traditional database management systems or information retrieval systems. The access methods available include viewing the data as a sequence of records for browsing, generating sets of records through string matching and Boolean combinations, and through generating a table schema and instantiating attribute values dynamically. As the access methods are all based on the same underlying data access model, the user can flip back and forth between the access methods in order to best accomplish the task at hand. An evaluation was conducted to test for correlations among a number of different variables

This study used the organizational affiliations of authors of published research to investigate interdisciplinary collaboration, a topic of increasing interest for both researchers and science policy-makers. It found that the amount of interdisciplinary collaboration research has steadily increased over a 20-year period. A journal's quality is positively correlated with the proportion of interdisciplinary papers it contains. However, there is insufficient evidence to support the belief that this type of research is, in general, of higher quality. The study also determined disciplines that collaborate most with the library and information science field. Copyright , Beech Tree Publishing.

Since the Groos droop of Bradford curves was reported, there has been a controversial explanation of its cause, i.e., that it is caused by an incomplete data set. In this study, a computer simulation was conducted to study the phenomenon. Incompleteness was characterized by two kinds of sampling, weighted and unweighted. Weighted sampling was used to simulate incompleteness of low productivity journals, unweighted sampling incompleteness at all productivity levels. Based on the result of 400 runs (two sampling methods x four sample sizes x ten data sets x five random runs), the hypothesis that the Groos droop is caused by incomplete data sets was rejected. The relationships between sample size, sampling method and the degree of the droop are also reported.

We report herein a nanoparticle-based methodology for detecting DNA in solution using inductively coupled plasma atomic emission spectrometry (ICP-AES) as a readout tool. This represents the first homogeneous solution assay of biologically significant targets by employing ICP-related techniques. Two types of particles are employed: silica nanoparticles or gold nanoparticles functionalized with oligonucleotides that are capable of hybridizing with half of the target DNA sequence as signal readout components, and magnetic microparticles functionalized with oligonucleotides that are capable of hybridizing with the other half of the sequence as capture components. In the presence of target DNA, three components form typical sandwich structures, and the application of a magnetic field could effectively separate them from the rest of the solution. Subsequent application of ICP-AES effectively provides an inorganic elemental readout for the diagnosis of target DNA.

This paper attempts to make a comparison between a western culture, Canada, and an eastern culture, China, in the use of business information. As part of a larger project of measuring the impact of information on development, four surveys of the business communities in these two countries were conducted. Two of them were carried out in Shanghai, China, with one aimed at small business and the other at mediumsized business. The other two were conducted in Canada with the same coverage as the corresponding surveys in China. Data were collected on the use of various types of information sources in business operations. Results show that informal information sources are more important and better used than the formal ones in both cultures. However, business people’s self-perception of their information use differs between the two cultures. Electronic information sources are currently poorly used in both countries. © 1998 Academic Press.