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A self-assembled three-dimensional (3-D) MoS2 microsphere-based memristor with a favorable ON/OFF resistance ratio of ~104, endurance, and retention time is demonstrated at room temperature. The formation and rupture of a localized Ag metallic filament, establishment and destruction of a boundary-based hopping path, and charge trapping and detrapping from the space charge region co-contribute to the bipolar resistive switching memory behaviours observed in the device of Ag/MoS2/ITO. This work may give insight into the mechanism of the resistive switching memory behaviours of a device with a 3-D micro-scale. [ABSTRACT FROM AUTHOR]

The elastic and structural properties of nanolaminate Zr2InC are studied by first-principles, and it is shown that, for any used modes, including the generalized gradient approximation (GGA) and localized density approximation, there always exists an ultraincompressibility along c axis between 70 GPa and 400 GPa. Such anomalous behavior is originated from the slowdown of core-valence charge transfer. The rapid shift of Zr atom along c axis also contributed much to the ultraincompressibility as it is greatly reduced once the Zr atom shift suspends along c axis above about 400 GPa. Both the elastic constants and the phononic vibrational frequencies investigations confirmed the structural unstable simultaneously. The Poisson's ratio investigations observed a higher ionic or weaker covalent contribution in interatomic bonding and the degree of ionicity increases with pressure. [ABSTRACT FROM AUTHOR]

1. Tile-grey plumage is a unique and rare feather type of local chicken breeds in China, but its genetic mechanism and corresponding genes remain unknown. 2. In order to identify the genetic basis and molecular characteristics of tile-grey plumage, this experiment investigated variations of melanocortin 1 receptor (MC1R) gene in Yunnan Piao chickens with typical tile-grey plumage characteristics in contrast with three Yunnan local breeds as well as two standard breeds with different plumage colour, and analysed the association between genic variation and tile-grey plumage. 3. Through sequencing and comparison of the entire coding region of the MC1R gene, a total of 10 SNP loci were detected, of which eight were non-synonymous mutations that cause amino acid changes. The gene frequency and genotype frequency of the MC1R mutation sites in different breeds and different plumage colour groups revealed that C69T, T212C and A274G were significantly associated with tile-grey plumage. Eighteen haplotypes of the MC1R gene were constructed based on 10 nucleotide variations and eight amino acid variations. Haplotype distribution and the median joining network in breeds and plumage colour groups revealed a main haplotype (hap2) for tile-grey plumage. Hap2 is unique to the tile-grey feather of Piao chicken, and the individuals carrying this haplotype account for 62.96% of the whole tile-grey chicken. 4. The results of this study are of significance for further analysis of the molecular basis of tile-grey plumage and the selective breeding of tile-grey plumage. [ABSTRACT FROM AUTHOR]

The thermal behavior of aluminum nanoparticles reacting with propylene oxide was investigated in normal incident shock waves. Their reactive temperature, which is about 2705±150 K, was experimentally determined by the emission strength of AlO. The reactive products were evaluated by x-ray diffraction, which shows that several different phases of Al2O3 are produced in different temperature regions. The scanning electron microscopy image of the reactive products shows that some holes, which were produced in the process of aluminum nanoparticles violently reacting with suboxides of aluminum, are found on the surface of the products. The data of transmission electron microscopy indicate that the grain diameters of the products were within the range of 20–90 nm. The geometry of propylene oxide was calculated and optimized using the Rb31yp function and the 6–311+g(d,p) basis set. The calculated results show that the diameter of the molecule is about 0.435 nm. The process of vaporizing and condensing of propylene oxide was investigated by electron microscopy, and the results show that the average drop diameter is 4.03 μm at t=70 s and then is 2.06 μm at t=120 s. It suggests that the average drop diameters tend to range from several nanometers to tens of nanometers, which is very close to the diameter of aluminum nanoparticles (average of 70 nm). Thus, we may consider them to react with each other in the gas phase in normal incident shock waves in the experiment. [ABSTRACT FROM AUTHOR]

Virus-induced gene silencing (VIGS) is a post-transcriptional gene silencing method used for unraveling gene functions. As an attractive alternative to mutant collections or stable transgenic plants, it has been widely used in reverse-genetics studies owing to its ease use and quick turnaround time. Turnip yellow mosaic virus (TYMV) has the ability to induce VIGS in Arabidopsis thaliana. However, the conventional vector construction is difficult and the efficiencies of the infection methods are low. Here, we improved the vector construction and viral infection methods, inserted an inverted-repeat fragment of the phytoene desaturase gene into a TYMV-derived vector by homologous recombination and transformed Brassica rapa with plasmid DNA harboring a cDNA copy of the TYMV genome through particle bombardment. An apparent photobleaching phenotype was detected and efficient VIGS was induced. An 80-bp fragment was sufficient to produce VIGS in leaves, stems, roots, flowers, siliques, and stalks of B. rapa. Because TYMV has a wide host range in Brassica, the VIGS system described here will contribute to the improvement of high-throughput technology and efficient functional research in B. rapa and other Brassicaceae crops. [ABSTRACT FROM AUTHOR]

Traditional procedures to treat vibrations of gyroscopic continua involve direct application of perturbation methods to a system with both a strong gyroscopic term and other weakly coupled terms. In this study, a gyroscopic modes decoupling method is used to obtain an equivalent system with decoupled gyroscopic modes having only weak couplings. Taking the axially moving string as an example, the instability boundaries in the vicinity of parametric resonances are detected using both the traditional coupled gyroscopic system and our system with decoupled gyroscopic modes, and the results are compared to show the advantages and disadvantages of each method. [ABSTRACT FROM AUTHOR]

The use of an electronic cooling system at the High Intensity heavy ion Accelerator Facility (HIAF) accelerator complex, which is being developed at the Institute of Modern Physics (China), to improve the efficiency of ion injection into the accelerator and reduce the spread of ion pulses in the beam has been proposed. Electron cooling of the ion beam was carried out due to the interaction of ions with a continuous electron beam with a current of up to 3 A, energy of up to 450 keV, and energy stability at the level of 10-4 or better. The electron beam energy recuperation was carried out at the expense of a power source with a power of 5-15 kW, which was located at the top of a high-voltage column—a high-voltage terminal. The operation of a prototype of power transmission system, which was based on a cascade transformer with a volumetric coil, has been considered. Such a transformer has a relatively low scattering inductance, which can significantly reduce the number of capacitors to compensate for it. It has been shown that this design made it possible to transfer power of up to 40 kW at small dimensions of the transformer and heat dissipation in it was not more than 10 kW. [ABSTRACT FROM AUTHOR]

Hot spots induced by lower hybrid wave in experimental advanced superconducting tokamak tokamak have caused high performance experiment disruption and serious damages to the guard limiters. Experimental and theoretical analyses have been carried out to study its physical mechanism. Plasma density scan experiments indicate that the wall temperature within the hot spots enhanced by a factor of 5 and increases with the plasma density near the antenna. A lower hybrid current drive (LHCD)-only density climb experiment shows that the carbon impurity decreases to a minimum value at certain plasma density and then increases with the line averaged plasma density. A model has been developed to explain the mechanism of sputtering of graphite tiles due to hot spots as the plasma density near the LHCD antenna and the time increases. A theoretical scaling of the heat flux driven by LHCD is also presented and is consistent with the experimental scaling in the Tore Supra tokamak. The simulation results show that the total sputtering flux density has a minimum at a certain plasma density and gradually increases as the plasma density increases or decreases away from the minimum value, and the increase in parallel heat flux near the antenna would enhance the sputtering flux density. The sputtering flux density trend is qualitatively consistent with the density scan experiments. The simulated temporal evolution of sputtered flux implies that the chemical sputtering could be a candidate for the carbon impurity explosion. [ABSTRACT FROM AUTHOR]

The recombination property of nitrogen (N)-related acceptor-bound states in ZnO has been investigated by photoluminescence (PL), time-resolved PL, and selective PL. Several possible recombination processes were discussed by analyzing the relaxation and recombination properties under large Coulomb interaction. It is strongly suggested that bound exciton emission dominates the recombination process related to the N acceptor. The recombination lifetime is 750 ps and the binding energy is 67 meV for N-acceptor-bound exciton at low temperature. [ABSTRACT FROM AUTHOR]

A three-dimensional full-annulus computational model for aerodynamic damping prediction based on energy method is demonstrated by the consideration of a transonic rotor which is designed for experimental research of flutter to improve understanding the influence of frequency mistuning and inter-blade phase angle mistuning on aeroelastic stability of transonic compressor. Each individual blade is capable of vibration with its own independent frequency and phase angle, thus modeling a full-annulus rotor with arbitrary mistuned blades. The numerical analyses of alternate, random, linear frequency mistuning, and random inter-blade phase angle mistuning are performed in detail. The studies of tuned rotor show that the aerodynamic damping for the blade first bending mode is most sensitive to inter-blade phase angle. Further investigations on various frequency mistuning and inter-blade phase angle mistuning indicate that inter-blade phase angle mistuning has almost no effect on average aerodynamic damping of rotor, while frequency mistuning significantly changes it. Especially, the aerodynamic damping is about 7 to 11 times at the least stable conditions of the study rotor. Furthermore, the divergence of individual blade aerodynamic damping enlarges due to both frequency and inter-blade phase angle mistuning. The individual blade aerodynamic damping for frequency mistuned blade is affected significantly by the blade local mistuned pattern and mistuning amount. Even more remarkable, the local instability of blade is induced by inter-blade phase angle mistuning at some case. It is beneficial to improve understanding the blade response and onset time differences of flutter in turbomachinery flutter problem. [ABSTRACT FROM AUTHOR]

E3 ubiquitin ligases are a large family of proteins that catalyse the ubiquitination of many proteins for degradation by the 26S proteasome. E3 ubiquitin ligases play pivotal roles in the process of insulin resistance and diabetes. In this review, we summarize the currently available studies to analyse the potential role of E3 ubiquitin ligases in the development of insulin resistance. We propose two mechanisms by which E3 ubiquitin ligases can affect the process of insulin resistance. First, E3 ubiquitin ligases directly degrade the insulin receptor, insulin receptor substrate and other key insulin signalling molecules via the UPS. Second, E3 ubiquitin ligases indirectly regulate insulin signalling by regulating pro-inflammatory mediators that are involved in the regulation of insulin signalling molecules, such as tumour necrosis factor-α, interleukin ( IL)-6, IL-4, IL-13, IL-1β, monocyte chemoattractant protein-1 and hypoxia-inducible factor 1α. Determining the mechanism by which E3 ubiquitin ligases affect the development of insulin resistance can identify a novel strategy to protect against insulin resistance and diabetes. [ABSTRACT FROM AUTHOR]

The feasibility of alleviating burst release of electrospun bead-on-string nanofiber scaffolds loaded with protein particles was evaluated, including an investigation of the influence of the beads number on the release profile. Bovine serum albumin–loaded dextran particles were used as the model drug and poly(lactic-co-glycolic acid) as the polymer to fabricate the bead-on-string nanofiber scaffolds by electrospinning. Both the bead structure and the distribution of the particles in the beads were examined by scanning electron, transmission electron, and fluorescence microscopy. The results of fluorescence microscopy suggested that the particles were well encapsulated by the beads of the fibers. In vitro release tests showed that a more sustainable release profile with less initial burst release could be obtained from the bead-on-string fibers than from smooth fibers with uniform diameter. In addition, when the number of the forming beads was not numerous enough to encapsulate all the particles in the suspensions, the release performance worsened because the surplus particles were not properly encapsulated. [ABSTRACT FROM PUBLISHER]

Purpose: Human epithelial growth factor receptor 2 (HER2) is over-expressed in several malignancies and represents an important therapeutic target. Aptamers are oligonucleotides that may potentially serve as tumor-homing ligand with excellent affinity and specificity for targeted cancer therapy. However, aptamers need to have nuclease resistance in order to function in vivo. The aim of this study was to generate a novel HER2 thioaptamer with enhanced nuclease resistance. Methods: The HER2 thioaptamer is selected in an evolutionary process called systematic evolution of ligands by exponential enrichment. Results: The thioaptamer could bind to the extracellular domain of HER2 with a K of 172 nM and had minimal cross reactivity to trypsin or IgG. Moreover, the thioaptamer was found capable of binding with the HER2-positive breast cancer cells SK-BR-3 and MDA-MB-453, but not the HER2-negative cells MDA-MB-231. Notably, the thioaptamer HY6 largely maintained its structural integrity facing the nucleases in serum, while regular DNA aptamers were mostly digested. Additionally, the thioaptamer retained the capability of binding with the HER2-positive cells in the presence of serum, whereas non-thionated HER2 aptamer lost the binding function. Conclusion: The results indicated that the selected thioaptamer was more resistant to nuclease than regular DNA aptamers and might potentially function as a HER2-targeting ligand in complicated environment. [ABSTRACT FROM AUTHOR]

In this paper, a two-dimensional damage model and its numerical solution are presented by means of fast Fourier transforms for anisotropic composite. First, the constitutive relation with damage variable is given from strain energy density based on the two-dimensional constitutive relation of anisotropic composites. Second, the crack growth principle is given according to maximum K criterion. Finally, a numerical solution can be obtained using the fast Fourier transforms method. Numerical examples of carbon-fibre unidirectional reinforced resin matrix composite are introduced. [ABSTRACT FROM AUTHOR]

A liquid material identification system based on electrical capacitance tomography technique is proposed. The structure of the sensor is discussed, and the parameters of designed capacitance tomography technique sensor are listed. The key parameters affecting the sensor performance and sensitivities are analysed. The performances of the sensor are simulated by COMSOL, and the practical performance of the capacitance tomography technique sensor is demonstrated in the experiments. The image reconstruction results are given which indicate the feasibility of the capacitance tomography technique system applied in liquid material identification. [ABSTRACT FROM AUTHOR]

The chaos and bifurcations in transverse motion of an axially moving thin plate under external and parametric excitations are studied herein. The geometric nonlinearity is introduced by using the von Karman large deflection theory. The coupled partial differential equations of transverse deflection and stress are truncated into a set of ordinary differential equations. By using the Poincaré map and the largest Lyapunov exponent, the dynamical behaviors including chaos are identified based on numerical solutions of the ordinary differential equations. The bifurcation diagrams are presented for different parameters, such as axially moving velocity, damping, external and parametric excitation amplitudes. The chaos is detected in both cases of external and parametric excitations. The interesting relevance between onset of chaos with the corresponding linear instability range are indicated in the external and parametric responses. [ABSTRACT FROM AUTHOR]

A coplanar waveguide (CPW) fed ultra-wideband (UWB) antenna with a notch band characteristic is presented in the paper. The radiation patch of the proposed UWB antenna is designed using cantor set fractal technology. The bandwidth is broadened by setting two symmetrical triangular tapered corners at the bottom of the wide slot of the proposed UWB antenna. The notched band characteristic is achieved by employing a T-shaped tuning stub at the top of the wide slot. The notched band can be controlled by adjusting the length and the width of the T-shaped tuning stub to give tunable notched band function. The proposed cantor set fractal wide slot UWB antenna has been designed in details and optimized. Experimental and numerical results show that the proposed antenna, with compact size of 26 x 21mm², has an impedance bandwidth range from 2.8GHz to 11GHz for voltage standing-wave ratio (VSWR) less than 2, except the notch band frequency 5.0GHz-6.3GHz for HIPERLAN/2 and IEEE 802.11a (5.1GHz-5.9GHz). [ABSTRACT FROM AUTHOR]

We show evidence that a structural martensitic transition is related to significant changes in the electronic structure, as revealed in thermodynamic measurements made in high magnetic fields. The effect of the magnetic field is considered unusual as many influential investigations of martensitic transitions have emphasized that the structural transitions are primarily lattice dynamical and are driven by the entropy due to the phonons. We provide a theoretical framework, which can be used to describe the effect of the magnetic field on the lattice dynamics in which the field dependence originates from the dielectric constant. [ABSTRACT FROM AUTHOR]

The commissioning of the cooler storage rings (CSR) was successful, and the facility provides new possibilities for atomic physics with highly charged ions. Bare carbon, argon ions, were successfully stored in the main ring CSRm, cooled by cold electron beam, and accelerated up to 1 GeV/u. Heavier ions as Xe44+ and Kr28+ were also successfully stored in the CSRs. Both of the rings are equipped with new generation of electron coolers which can provide different electron beam density distributions. Electron-ion interactions, high precision X-ray spectroscopy, complete kinematical measurements for relativistic ion-atom collisions will be performed at CSRs. Laser cooling of heavy ions are planned as well. The physics programs and the present status will be summarized. [ABSTRACT FROM AUTHOR]

A printed toothbrush-shaped antenna is proposed for millimeter wave communication. The designed antenna features with a compact size is 7 × 10 mm2, and satisfies the VSWR requirement less than 2.0 in the frequency band from 32 GHz to more than 38 GHz. Simulated and measured results for main parameters such as return loss, impedance bandwidth, and radiation patterns are also discussed herein. The study shows that modeling of such antennas, with simplicity in designing and feeding, can well meet millimeter-wave wireless communication. [ABSTRACT FROM AUTHOR]

A novel dmit organometallic complex: [(C2H5)4N]2[Cu(dmit)2] (dmit2-=1,3-dithiole-2-thione-4,5-dithiolate), abbreviated as EtCu, was synthesized. Afterwards its optical nonlinearities in acetone solution at 532 nm and 1064 nm were studied by the Z-scan technique with laser pulses of picosecond duration. The two-photon absorption at 1064 nm and the saturable absorption at 532 nm were observed. The Z-scan curves also revealed that EtCu sample solutions exhibited self-defocusing effects at both wavelengths. The origins were analyzed for the differences between the results. All the outcomes suggest that this material is potential for nonlinear optical device applications. [ABSTRACT FROM AUTHOR]

The adsorption equilibrium and kinetics of N-lauroyl- N-methylglucamide (MEGA-12) aqueous solution were studied. The critical micelle concentration, the maximum surface excess, and the minimum area per molecule of MEGA-12 were obtained as 2.48 × 10−4 mol/l, 4.883 × 10−6 mol/m2, and 0.34 nm2, respectively. The adsorption kinetics of MEGA-12 was studied by the maximum bubble pressure method. The result shows that in the initial stage or at small MEGA-12 concentrations, the adsorption process is diffusion-controlled; however, it changes to become adsorption-controlled at the end of the process. The effects of temperature, inorganic salts, alcohols, and ionic liquid on the adsorption kinetics were also discussed. [ABSTRACT FROM AUTHOR]

Quantitative structure-pharmacokinetic/pharmacodynamic (PK/PD) relationship (QSPR) techniques and chemometric methods were employed to classify fluoroquinolones with respect to their activity against Streptococcus pneumoniae. Density functional theory (DFT) was used to calculate a set of molecular descriptors (properties) for 13 synthetic fluoroquinolones. The descriptors were further analyzed using chemometric methods including principal component analysis (PCA), hierarchical cluster analysis (HCA), and stepwise discriminant analysis (SDA). The PCA and SDA methods were employed in order to reduce the dimensionality and select a subset of variables that would be more effective for classifying the fluoroquinolones according to their degree of antipneumococcal activity. The methods of PCA, SDA and HCA were quite efficient to classify 13 compounds in two groups (active and inactive), and the net charge on ring B ( Q B), molecular volume (VOL), and partition coefficient (log P ) were found to be descriptors important for the classification. These methodologies of PCA, SDA and HCA provide a reliable rule for classifying new fluoroquinolones with respect to antipneumococcal activity. The application of the SPP relationship is of considerable value for clinicians, drug developers, and regulators because PK/PD principles form the basis of modern antimicrobial chemotherapy. [ABSTRACT FROM AUTHOR]

Two new phenyl esters, named as euosmoside A ( 1 ) and euosmoside B ( 2 ), have been isolated from the leaves and twigs of Litsea euosma . Their structures were elucidated on the basis of spectroscopic methods. [ABSTRACT FROM AUTHOR]

The dynamic stability of an axially accelerating viscoelastic beam with two fixed supports is investigated. The Kelvin model is used for the constitutive law of the beam. A small simple harmonic is allowed to fluctuate about the constant mean speed applied to the beam, and the governing equation is truncated using the Galerkin method based on the eigenfunctions of the stationary beam. The averaged equations are derived for the cases of subharmonic and combination resonance. Finally, numerical examples are presented to demonstrate the effects of the viscosity coefficient, the mean axial speed and the beam bending stiffness on the stability boundaries. [ABSTRACT FROM AUTHOR]

We study the dynamics of multipartite entanglement under decoherence induced by the environment consisting of a fermionic bath. Based on the algebraic measure of entanglement-negativity, we analyze the time evolution of entanglement of both pure states and mixed ones, and find that entanglement evolution depends on both bath temperature and the number of qubits of the system. A linear space SLDF which is dynamically decoupled from the environment is identified in the sense of linear entropy to symbolize the environment effect. [ABSTRACT FROM AUTHOR]

The experimental results of angular distribution of hot electrons in the interaction of a 60 fs, 125 mJ, 800 nm, ∼10[sup 17] W cm[sup -2] laser pulse with A1 targets are reported. Three obvious peaks of hot electrons emission have been observed, as there is a weak normal component of the laser electric field. These emission peaks are located in the directions of the specular reflection of the laser, the target normal, and the backreflection of the laser, respectively. In the case of the P-polarized laser pulse, which has a strong normal component of the laser electric field, the peak in the backreflection of the laser disappeared, and only two obvious peaks of hot electron emissions existed. It shows that the different directions of hot electrons emission are dominated by different absorption or acceleration mechanisms. The experimental result of the hot electrons energy spectrum at the target normal shows that the effective temperature of hot electrons is about 190 keV, which is consistent with a scaling law of the resonance absorption. [ABSTRACT FROM AUTHOR]

Susceptibility to the human autoimmune disease IDDM is strongly associated with those haplotypes of the major histocompatibility complex (MHC) carrying DQB1 alleles that do not encode aspartic acid at codon 57. Similarly, in a spontaneous animal model of this disease, the NOD mouse, the genes of the MHC play an important role in the development of diabetes. The DQB1 homolog in NOD mice, I-Ab(g7), encodes a histidine at codon 56 and a serine at codon 57, while all other known I-Ab alleles encode proline and aspartic acid, respectively, at these positions. We therefore mutated the NOD I-Ab allele to encode proline at position 56 and aspartic acid at position 57 and introduced this allele onto the NOD genetic background to study the effect of these substitutions on susceptibility to diabetes. No transgenic mice developed diabetes by 8 months of age, and transgenic mice had markedly reduced lymphocytic infiltration in the pancreas compared with nontransgenic littermates. Furthermore, splenocytes from transgenic mice failed to proliferate or secrete gamma-interferon in response to a panel of beta-cell autoantigens, although the mice did produce beta-cell specific antibodies. Interestingly, the proportion of IgG1 and IgE relative to IgG2a comprising these autoantibodies was much greater in transgenic mice compared with nontransgenic control mice. Finally, T-cells from transgenic mice inhibited the adoptive transfer of diabetes to irradiated recipients. This inhibition was partially reversed by treatment of the recipients with a combination of anti-interleukin (IL)-4 and anti-IL-10 monoclonal antibodies. Thus, a transgenic class II MHC allele encoding aspartic acid at B57 prevents diabetes, in part, by promoting the production of IL-4 and IL-10, which interfere with the effector phase of the diabetic process. [ABSTRACT FROM AUTHOR]

IDDM is a T-cell-mediated autoimmune disease in which the insulin-producing beta-cells are destroyed. The disease process is complex, involving the recognition of several beta-cell autoantigens. One of these, GAD65, appears to have a critical and not fully defined role in IDDM in humans and in the NOD mouse. We provide evidence that an ongoing diabetogenic response in NOD mice can be suppressed after intravenous administration of GAD65, but not by other beta-cell autoantigens. Furthermore, suppression of the diabetogenic response is mediated by the induction of GAD65-specific CD4+ regulatory T-cells. Finally, cytokine analysis indicates that these CD4+ regulatory T-cells have a T-helper 2 phenotype. [ABSTRACT FROM AUTHOR]

In a previous study we have shown that Lewis rats were completely protected from adjuvant arthritis by pretreatment with a nonapeptide (residues 180-188) of the 65-kD mycobacterial heat shock protein. Here we address questions of specificity and mechanism(s) of protection. We demonstrate that complete protection against adjuvant arthritis can only be achieved by pre-immunization with the nonapeptide, while pretreatment with either the octapeptide (residues 181-188) of the 65-kD heat shock protein or unrelated immunogenic peptides failed lo affect adjuvant arthritis. Interestingly, pretreatment with the nonapeptide of the 6.S-kD heat shock protein did not protect Lewis rats from type H collagen-induced arthritis. These results demonstrate that protection is both epitope and disease specific. Co-injection of the nonapeptide with mycobacterial antigen even at a weight ratio of 5:1 (nonapeptide : mycobacteria) failed to influence the disease, suggesting that the role of the nonapeptide is not as a 'blocking peptide'. T cells from rats immunized with nonapeptide respond to the nonapeptide as well as to mycobacteria in vitro, and adoptively transfer protection to naive recipients. The data indicate that the nonapeptide-induced protection may result from a T cell-mediated specific suppression. [ABSTRACT FROM AUTHOR]