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In this study, we prepared three different silicon quantum dots (SiQDs-1, SiQDs-2 and SiQDs-3) by hydrothermal synthesis with rose Bengal as the reducing agent and triacetoxy(methyl)silane and allyloxytrimethylsilane as silicon sources.

It is an urgent challenge to develop efficient antibacterial agents against resistant bacteria in the treatment of infectious diseases. Carbon quantum dots (CQDs) have attracted much attention owing to their good stability, low toxicity and excellent biocompatibility. In this work, CQDs doped with different contents of the element phosphorus (P) were prepared by a simple hydrothermal method using valine as a carbon source, triethylamine as a nitrogen source and different volumes of phosphoric acid as a phosphorus source. The average diameter and the surface charge could be regulated from 2.89 nm to 1.56 nm and +2.58 mV to +5.47 mV by increasing the content of the element P in these CQDs. Importantly, these CQDs showed effective bacterial inhibition against

A nonstoichiometric La

Corneal defect is a common disease in ophthalmology caused by trauma, inflammation, drug toxicity, or surgery. To investigate the effect of germinal peptide eye drop on corneal epithelial and stromal defects after lamellar keratectomy in rabbit model.Eighty-five male New Zealand white rabbits were divided into five groups: Germinal Peptide eye drop at three different concentration groups, normal saline (negative control group), recombinant human epidermal growth factor (rh-EGF) eye drop (positive control group). Corneal epithelial and stromal defects of around 150-200 μm in depth were created with an 8 mm diameter trephine in the center of the right eyes of all animals.Germinal peptide eye drop with the concentration of 0.001%, 0.002%, and 0.004% and rh-EGF eye drop were more effective in promoting healing, reducing opacity, and edema during the process of corneal epithelial and stromal defect regeneration compared with 0.9% normal saline. No significant difference was observed among the three different doses of germinal peptide eye drop. Compared with the saline control group, the structures of the regenerated corneas were more orderly and less inflammatory cell infiltration was observed in the germinal peptide eye drop groups and the rh-EGF eye drop group.Germinal peptide eye drop (0.001%, 0.002%, and 0.004%) can significantly stimulate the regeneration of corneal epithelia and stroma and reduce corneal opacity and edema. Dose dependency was not observed in the current study.

Deformation flexibility of two-dimensionally connected tetrahedral network and Ga3+ ion with variable coordination are reported to be the key factor for oxide ion migration in La1+xSr1−xGa3O7+0.5x materials, which are well-known oxide ion conductors with remarkable conductivity at the temperature range 600–900 °C. In this work, La1+xSr1−xGa3S6O1+0.5x materials which also adapt melilite structure were prepared at high temperature in a quartz tube after being vacuumed. The prepared samples were then studied by complementary techniques, including X-ray diffraction (XRD), alternative current (AC) impedance spectroscopy, and density functional theory (DFT). The XRD data together with Rietveld refinement results showed that La atoms failed to replace Sr atoms in La1+xSr1−xGa3S6O1+0.5x materials, leading to two phases in the products. This was consistent with the high defect formation energy (higher than 2.76 eV) of La atoms substituting for Sr atoms. In addition, alternative current impedance spectroscopy measurements demonstrated no ionic conduction responses in these melilite La1+xSr1−xGa3S6O1+0.5x materials, agreeing well with the fact that the La atoms were not able to substitute for Sr atoms and no interstitial oxide ions were introduced in any phases of the products.

T helper 2 (Th2) cytokine production by invariant natural killer T (iNKT) cells is involved in the development of asthma, but the regulation of Th2 cytokines in iNKT cells remains unknown. Although it is known that progranulin (PGRN) induces the production of Th2 cytokines in iNKT cells in vivo, the underlying mechanism is not clear. This study aims to investigate the role of PGRN in iNKT cells. The effects of PGRN on the differentiation of iNKT cells was detected by flow cytometry. Then stimulation of iNKT cells and airway resistance were carried out to evaluate the function of PGRN on iNKT cells. Furthermore, the mechanisms of PGRN in regulating iNKT cells was investigated by RT-PCR, WB, confocal and luciferase reporter assays. The absolute number of iNKT cells decreased in PGRN KO mice despite an increase in the percentage of iNKT cells. Furthermore, analyzing the subsets of iNKT cells, we found that NKT2 cells and their IL-4 production were reduced. Mechanistically, the decrease in NKT2 cells in the PGRN KO mice was caused by increased expression of enhancer of zeste homolog 2 (EZH2), that in turn caused increased degradation and altered nuclear localization of PLZF. Interestingly, PGRN signaling decreased expression of EZH2 and treatment of the PGRN KO mice with the EZH2 specific inhibitor GSK343 rescued the defect in NKT2 differentiation, IL-4 generation, and PLZF expression. Altogether, We have revealed a new pathway (PGRN-EZH2-PLZF), which regulates the Th2 responses of iNKT cells and provides a potentially new target for asthma treatment.

The involved interaction information concerning adsorbate-adsorbate and adsorbate-adsorbent is indispensable for developing and optimizing adsorption treatment of dye wastewater. Single and bi-solute adsorption of methyl orange (MO), indigo carmine (IC), and methylene blue (MB) on polystyrene anion exchanger (PsAX), defunctionalized version of PsAX (DF-PsAX), and hyper-cross-linked polystyrene adsorbent (MN200) were investigated to obtain a mechanistic understanding. Under acidic condition, higher adsorption efficiencies of PsAX due to extra intermolecular interactions of MO between the protonated tertiary amine group and the sulfate groups were observed, while strong alkaline condition is favorable for the adsorption of IC and MB by PsAX. MN200 exhibited much larger adsorption capacity toward MB than that toward MO or IC, because the fused-rings structure of MB is more polarizable and can form stronger nonionic intermolecular attractions with the matrix structure of polystyrene adsorbents. Bi-solute adsorption reveals that MO has obvious competitive effect toward IC adsorption at low concentrations, but it is not the case for the adsorption at high concentrations, where IC molecules can form intermolecular H-bonding interactions to defend the competition. the thermodynamic parameters confirm the endothermic and spontaneous nature of MO adsorption by PsAX, and ≈ 48 KJ mol−1 of the enthalpy change (∆H) imply the adsorption is not just physical absorption. Additionally, water/ethanol mixture solution of NaCl can almost thoroughly regenerate the exhausted PsAX, whereas only aqueous solution without ethanol is invalid.

International audience; Lowering the operating temperature of solid oxide fuel cells (SOFCs) requires high performance oxide ion conductor electrolytes. Recently tetrahedra-based structures have been attracting considerable attention for oxide ion conductor development, among which the layered tetrahedral network melilite structure appears particularly interesting owing to its remarkable capability to accommodate and transport interstitial oxide ions, compared with isolated tetrahedral anion structures. Stabilization and migration mechanisms of interstitial oxide ions in melilites have been systematically investigated using local structural relaxation from both electrostatic Coulomb interaction and chemical bonding aspects based on atomic and electronic structures respectively using experimental and theoretical approaches. These reveal cationic size and chemical bonding effects on stabilization and migration mechanisms of interstitial oxide ions. Lately, full crystallization from glass, an innovative synthesis method, was employed to produce new metastable melilite oxide ion conductors which are inaccessible using classic solid state reaction owing to cationic size effect. Finally, the thermal and chemical stability at low temperature and the high oxide ion conductivity of the best melilite oxide ion conductors based on LaSrGa 3 O 7 are likely to provide real possibilities of applications of melilite-type electrolytes in SOFCs and other related devices.

Germinal peptide is being developed to treat corneal injuries. The purpose of this study was to investigate its effect on corneal epithelial cells in vitro and its ability to promote healing in an alkali injury model in vivo. Cultured rabbit corneal epithelial cells were treated with germinal peptide at three concentrations. Cell proliferation and migration were assessed and compared with the effect of recombinant human epidermal growth factor (rh-EGF). In vivo, the corneas of New Zealand albino rabbits were chemically burned with 1 mol/l NaOH for 30 s. The injured eyes were topically treated with germinal peptide (10, 20, and 40 μg/ml), rh-EGF, or phosphate-buffered saline thrice daily. At fixed time points post injury, the healing of the cornea and its histopathology were evaluated. There was no difference in the effect of germinal peptide on cultured cell proliferation. However, cell migration was significantly higher than that in the control groups, with germinal peptide at concentrations of 20 and 40 μg/ml being the most efficacious. In vivo, 20 and 40 μg/ml germinal peptide significantly alleviated corneal opacity and edema. By day 21, the areas of corneal neovascularization in the germinal peptide-treated groups were smaller than those in the rh-EGF and control groups. The repaired corneas in the germinal peptide- and rh-EGF-treated groups also had more corneal epithelial layers and fewer inflammatory cells than the controls. Germinal peptide may be developed as a novel topical treatment agent for corneal wound healing in clinical settings.

Interstitial oxide ion conducting Pb0.7La0.3WO4.15 scheelite material was synthesized by a traditional high-temperature solid state reaction method and its structure was analyzed by Rietveld method on neutron powder diffraction (NPD) data, which indicates the positional disorder owing to the existence of extra oxygen from donor doping of La3+ for Pb2+. Atomistic static-lattice simulation indicates that interstitial oxygen defects are accommodated via entering into the bonding environment of WO4, resulting in local corner-shared W2O9 polyhedral units. The molecular dynamic simulations show that the interstitial oxide ion can move among the WO4 tetrahedral units through a synergic mechanism involving continuous breaking and reformation of W2O9 units assisted by rotation and deformation of WOn polyhedra and knock-on process between oxygen atoms.

The “114” oxides LnBa(Co/Fe)4O7+δ represent a new family of materials that exhibits intriguing physical properties, including geometrically frustrated magnetism, oxygen storage, and magnetoelectric couplings. Various chemical substitutions have been conducted to modify their crystal and magnetic structures as well as physical properties. However, the principles beneath the substitution-induced structural evolution and charge/cationic ordering have not yet been understood. Thus, in this contribution, two complete solid solutions of MAZn2Ga2O7 (M = Ca2+, Sr2+; A = Sr2+, Ba2+) were designed, synthesized, and characterized by Rietveld refinements based on high-resolution X-ray diffraction (XRD) and neutron diffraction (ND) data. The structure symmetry of MAZn2Ga2O7 is determined by the cationic size mismatch between M and A cations that can be defined by the tolerance factor t, i.e., symmetry transitions from P63mc (t > 0.87) to P31c (0.87 > t > 0.75) and to Pna21 (t < 0.75) were observed for MAZn2Ga2O7, asso...

In modern petroleum extraction industry, Internet of Things (IoT) technology is widely used, and various of sensors constitute a typical cyber-physical systems (CPS). There are more requirements of interoperability and interaction between well site device systems. In such industrial critical domain, high-confidence is also important. This paper presents the requirements and running environment of developing high-confidence CPS. To satisfy the requirements of interoperability and data exchange among heterogeneous well site systems, a foundation framework with well defined interfaces and quality of service constraints was established. Based on this framework, designing high-confidence petroleum extraction CPS using Model-Driven Architecture approach is proposed, the long-lived models produced in the process that can be applied to any implementation technologies and platforms through model transformation which make the systems more portable. A case study shows the detail of the development process and using communication bridges to build relationships between models. At last some important problems which need to be paid more attention in model transformation process are discussed.

Topotactic reduction of the perovskite oxide TbBaCo2O5.5 with CaH2 leads to a new crystalline phase TbBaCo2O4.5, adopting a 2 × 2 × 1 superstructure compared to TbBaCo2O5.5. The structure consists of a corner-shared network of square pyramidal CoO5 and trigonal planar CoO3 units. Magnetic susceptibility and variable temperature neutron diffraction data reveal that TbBaCo2O4.5 adopts a G-type antiferromagnetically ordered structure (TN ∼ 322 K). The ordered moments are consistent with the presence of low-spin Co2+ (S = 1/2) in trigonal-planar coordination and high-spin Co2+ centers in square pyramidal coordination. TbBaCo2O4.5 shows lower conductivity than TbBaCo2O5.5, which is consistent with the p-type conduction behavior. The unique anion vacancy arrangements in TbBaCo2O4.5 further complement the role of A-cations in controlling the oxygen vacancy distribution in LnBaCo2O5+δ series and demonstrate more opportunity to tune the structural and physical properties based on cationic and anionic lattice coupling.

Topotactic reduction of the perovskite oxide TbBaCo

Fe-loaded nanocomposites (NCs) have proven to be a promising category of adsorbents for efficiently removing phosphate [P(V)] from aqueous media. In this study P(V) removal and the possible adsorption mechanisms were investigated for four Fe-loaded NCs, which were developed by loading ferric (hydr)oxide (Fe[H]O) nanoparticles (NPs) of different crystal formations inside polystyrene anion exchanger (PsAX). Fe[H]O-PsAX@25 (with amorphous Fe[H]O NPs) was synthesized by in situ deposition method under ambient condition, and it served as source material to yield Fe[H]O-PsAX@75, @150, and @200 by hydrothermal treatment for 24 h under 75, 150, and 200 °C, respectively. Macroscopic experiments revealed that these NCs have decent P(V) adsorption abilities at pH 5–10 except Fe[H]O-PsAX@200, the functional groups (R-N+[CH3]3) of which severely suffered from degradation or even elimination as evidenced by FT-IR spectra and its exchange capacities. XPS results spectroscopically confirmed three different P(V) adsorption mechanisms, that is, ion-exchange interactions with R-N+[CH3]3, ligand-exchange interactions with amorphous Fe[H]O NPs, and ligand-exchange interactions with crystalline NPs (i.e., hematite). The ion-exchange interactions lack selectivity toward P(V) and would be invalidated by higher concentrations of competing sulfate anions, while ligand-exchange interactions, especially from amorphous Fe[H]O NPs, exhibited great P(V) adsorption selectivity. Acid-dissolution resistance of the loaded Fe[H]O NPs was significantly improved when being transferred into crystal formation, but their P(V) adsorption capacities gradually decreased during transformation process partially because of enlarging particle sizes and thus lessening effective surface areas.

The "114" oxides LnBa(Co/Fe)

Based on the definition and properties of discrete fractional Fourier transform (DFRFT), we introduced the discrete Hausdorff-Young inequality. Furthermore, the discrete Shannon entropic uncertainty relation and discrete Renyi entropic uncertainty relation were explored. Also, the condition of equality via Lagrange optimization was developed, as shows that if the two conjugate variables have constant amplitudes that are the inverse of the square root of numbers of non-zero elements, then the uncertainty relations reach their lowest bounds. In addition, the resolution analysis via the uncertainty is discussed as well.

This paper investigates the generalized Parseval’s theorem of fractional Fourier transform (FRFT) for concentrated data. Also, in the framework of multiple FRFT domains, Parseval’s theorem reduces to an inequality with lower and upper bounds associated with FRFT parameters, named as generalized Parseval’s theorem by us. These results theoretically provide potential valuable applications in filtering, and examples of filtering for LFM signals in FRFT domains are demonstrated to support the derived conclusions.

In this paper, a new signal separation method mainly for AM-FM components blended in noises is revisited based on the new derived time-varying bandpass filter (TVBF), which can separate the AM-FM components whose frequencies have overlapped regions in Fourier transform domain and even have crossed points in time-frequency distribution (TFD) so that the proposed TVBF seems like a “soft-cutter” that cuts the frequency domain to snaky slices with rational physical sense. First, the Hilbert transform based decomposition is analyzed for the analysis of nonstationary signals. Based on the above analysis, a hypothesis under a certain condition that AM-FM components can be separated successfully based on Hilbert transform and the assisted signal is developed, which is supported by representative experiments and theoretical performance analyses on a error bound that is shown to be proportional to the product of frequency width and noise variance. The assisted signals are derived from the refined time-frequency distributions via image fusion and least squares optimization. Experiments on man-made and real-life data verify the efficiency of the proposed method and demonstrate the advantages over the other main methods.

SUMMARYThe rickettsial bacteriumEhrlichia ruminantiumis the causative agent of heartwater, a serious tick-borne disease in ruminants. The genetic diversity of organisms in the field will have implications for cross-protective capacities of any vaccine developed, and for an effective vaccine design strategy proper genotyping and understanding of existing genetic diversity in the field is necessary. We searched for variable-number tandem-repeat (VNTR) loci for use in a multi-locus VNTR analysis (MLVA). Sequencing analysis of 30 potential VNTRs using a panel of 17 reference strains from geographically diverse origins identified 12 VNTRs with allelic profiles differing between strains. Application of MLVA to 38E. ruminantium-infectedAmblyomma variegatumcollected from indigenous cattle in 6 different districts of Uganda identified 21 MLVA types. The discriminatory power of MLVA was greater than that ofmap1PCR-restriction fragment length polymorphism analysis, with which only 6 genotypes were obtained. The high discriminatory power as well as cost- effective performance of MLVA provide the potential for this technique to be applied in the future with respect to optimizing vaccine trials by identifying local strain diversity, and also raise the possibility of exploring the association betweenE. ruminantiumgenotypes and phenotypes such as pathological outcome in the ruminant host.

The present study was conducted to demonstrate the epidemiological distribution of bovine babesiosis in the northern regions of Thailand. A total of 700 serum samples of dairy cows in the northern provinces (Chiang Rai, Chiang Mai, Lumpang, and Mae Hong Sorn) were tested for antibodies against Babesia bovis and B. bigemina. Species-specific enzyme-linked (rRAP-1/CTs) were performed. According to the results, 517 (73.8%) and 484 (69.1%) were positive for B. bovis and B. bigemina, respectively. In addition, 370 (52.9%) were positive for mixed infections by both ELISAs. On the other hand, all samples were also examined by the indirect fluorescent-antibody test (IFAT) with B. bovis- and B. bigemina-infected blood smears. According to the IFAT, 482 (68.8%) and 531 (75.8%) were positive for these infections, respectively. The overall concordances between the ELISA and IFAT techniques were 93.6% and 90.7% for B. bovis and B. bigemina infections, respectively. These results indicated that babesia infections are widespread in the northern parts of Thailand. To our knowledge, this is the first report describing the epidemiology of Babesia infections using rRAP-1/CT-based ELISAs in these areas.

Serum- and glucocorticoid-inducible kinase SGK1 functions as an important regulator of transepithelial sodium transport by activating epithelial sodium channel in renal tubules. Considerable evidence demonstrated that SGK1 was associated with hypertension and fibrosing diseases, such as diabetic nephropathy and glomerulonephritis. The present study was performed to evaluate the role of SGK1 played in immunoglobulin A (IgA) nephropathy.Seventy-six patients of biopsy-proven IgA nephropathy and 33 healthy volunteers were enrolled in this study. All patients and healthy volunteers' urinary and serum samples were tested for SGK1 expression by indirect enzyme-linked immunosorbent assay. Meanwhile all patients' renal tissues were semi-quantified for SGK1 expression by immunohistochemistry assay. The relationships between SGK1 expressions and clinical or pathological parameters were also assessed.SGK1 expression was upregulated in urine and renal tubules in patients of Oxford classification T1 and T2, whereas its expression in serum did not increase significantly. Relationship analysis indicated that urinary and tissue SGK1 expressions were associated with heavy proteinuria and renal insufficiency in patients with IgA nephropathy. On the other hand, RAS blockades would reduce the SGK1 levels both in urine and renal tissues.These results suggested that urinary SGK1 should be a good indicator of tubulointerstitial damage in patients of IgA nephropathy. SGK1 expressions in urine and renal tissues were associated with the activity of renin-angiotensin-aldosterone system.

The spotted fever group (SFG) rickettsiae are obligate intracellular bacteria transmitted by ticks that cause several tick-borne rickettsioses in humans worldwide. This study was intended to determine the prevalence of SFG rickettsiae in Amblyomma variegatum from 7 districts across Uganda. In addition to sequencing of gltA and ompA genes, identification of Rickettsia species based on the sizes of highly variable intergenic spacers, namely, dksA-xerC, mppA-purC, and rpmE-tRNAfMet was carried out. Application of multiplex PCR for simultaneous amplification of 3 spacers combined with capillary electrophoresis separation allowed simple, accurate, and high-throughput fragment sizing with considerable time and cost savings. Rickettsia genus-specific real-time PCR detected 136 positives out of 140 samples, giving an overall prevalence of 97.1%. Most samples (n = 113) had a size combination of 225, 195, and 341 bp for dksA-xerC, mppA-purC, and rpmE-tRNAfMet, respectively, which was identical to that of R. africae, a causative agent of African tick bite fever. In addition, several samples had size variants in either dksA-xerC or rpmE-tRNAfMet. Nonetheless, the partial sequences of gltA and ompA genes of samples of all size combinations showed the greatest similarity to R. africae (99.3–100% for gltA and 98.1–100% for ompA). Given these results, it is highly possible that the tested ticks were infected with R. africae or closely related species. This is a first report on molecular genetic detection of R. africae and its high endemicity in Uganda. Clinicians in this country should be aware of this pathogen as a cause of non-malarial febrile illness. This study provided a starting point for the development of Rickettsia species identification based on the sizes of intergenic spacers. The procedure is simple, rapid, and cost-effective to perform; hence it might be particularly well suited for preliminary species identification in epidemiological investigations. The results may be more detailed and reliable when simultaneous sequencing analysis is performed.

An enhancement algorithm for weather fax map with zero-mean Gaussian noise is proposed based on BEMD and self features of meteorological facsimile maps. First decompose the noised meteorological facsimile map to IMF 1 and a residue, then estimate the variance of the noise via BEMD and IMF 1 through the intrinsic relation between the variances of IMF 1 and the noise. According to the current time and location of the ship and the frequency loaded in the meteorologic electrograph, the type and the geographic information of the meteorological facsimile map is obtained. Then the noised map subtracts the geographic information after map matching. Last perform non-local mean filtering and binary value optimization on key words and marks to obtain the refined map. Experiments prove that the proposed algorithm has better performance for the enhancement of meteorological facsimile maps.

This paper presents an alterative bi-dimensional empirical mode decomposition based on the assisted images constructed in advance according to needed bandwidth. Firstly, the given assisted image and its negative counterpart are added to the original image respectively to construct the two images to be decomposed. Secondly, the decomposed IMFs from the two images are added together to get the IMFs, in which the added images are canceled out with less mode-mixing and boundary effects. The contribution of the method lies in the low time-cost and controllable bandwidth, which exist in ASBEMD. Lastly, the efficiency and performance of the method are given through theoretical analysis and its application in remote sensing image fusion, which outperforms some previous approaches.

Quantum dots (QDs) have been receiving a lot of attention recently for their unique fluorescence properties that can be used in drug discovery and bioimaging applications. We have in this article focused particularly on QDs and used it as a transfection vector as well as a fluorescence label for the RNA interference research. The siRNAs were designed to knock down the bcr/abl oncogene in leukaemia K562 cells. EDAC used as a cross-linker, COOH-functionalized QDs were conjugated with NH2-modified siRNAs to generate QD-siRNA conjugates. We also demonstrated their application to the K562 cells. Using such constructs, the delivery and transfection of siRNAs could be monitored by the presence of fluorescent QDs in the conjugates. QDs not only exhibited superior photostability for labeling cells but also worked as a good vector that remarkably increased the transfection efficiency of siRNAs into the cells. Cell proliferation was examined by the MTT assay and cell apoptosis by FACS. Our data have shown that the QD-siRNA conjugates could efficiently inhibit the viability of K562 cells and induced their apoptosis. In summary, QDs can be considered strong tools for the functional analysis of RNAi.

Here we present a hybrid method of generating a hierarchical recognition system based on example learning. The method is 'hybrid' in that it uses both conventional Artificial Intelligence and Artificial Neural Network techniques. The integrated hierarchical recognition system, called IHKB (integrated hierarchical knowledge base), has a tree structure consisting of nodes and leaves. Each node is indexed by an attribute set and contains a small Kohonen network (KN). Each leaf represents a recognition class. The system uses a conceptual function to instruct the process of attribute choosing. Whenever a suitable attribute set is obtained for a certain group of training examples, a small Kohonen net is built and trained with those examples. This allows the machine to focus on special features of these training examples and thus to better describe the special characteristics of these patterns. Typically, there are many KNs in a IHKB, the number depending on the number of attribute sets. The position of each KN in the tree is fixed automatically. When the construction is complete, the training examples are classified by Kohonen nets, and recognition is achieved by a path from the root of the tree to a leaf. The method has been tested on individual handwritten character recognition, showing that high recognition rates can be achieved given enough training examples.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper discusses and analyses the Vogl''s BP Network accelerating algorithms, and to counter its defect, proposes two improved methods. The first one is called (eta) -increasing relative restriction method which restricts the increasing speed of (eta) effectively when training error rises inversely. The second one is called (eta) -increasing absolute restriction method. This method changes (eta) according to the given relational expression of learning rate (eta) and training number (Tau) . When (Tau) becomes large enough, the increasing rate of (eta) tends to zero, thus restricting the rising of (eta) once and for all. As long as we adjust the expression parameter properly, the (eta) -increasing speed can be limited to the nearby regions of maximum value of (eta) that don''t cause training oscillation. A test result is given in the paper. The result shows that the improved algorithms can decrease the oscillatory frequency and amplitude of learning, avoid repetitive learning, and make training converge as quickly as possible. The convergence speed is 10 times or more than that of Vogl''s algorithm.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.