The role of time and place cues in the detection of frequency modulation by hearing-impaired listeners

Frequency modulation detection limens (FMDLs) were measured for five hearing-impaired (HI) subjects for carrier frequencies f(c) = 1000, 4000, and 6000 Hz, using modulation frequencies f(m) = 2 and 10 Hz and levels of 20 dB sensation level and 90 dB SPL. FMDLs were smaller for f(m) = 10 than for f(m) = 2 Hz for the two higher f(c), but not for f(c) = 1000 Hz. FMDLs were also determined with additional random amplitude modulation (AM), to disrupt excitation-pattern cues. The disruptive effect was larger for f(m) = 10 than for f(m) = 2 Hz. The smallest disruption occurred for f(m) = 2 Hz and f(c) = 1000 Hz. AM detection thresholds for normal-hearing and HI subjects were measured for the same f(c) and f(m) values. Performance was better for the HI subjects for both f(m). AM detection was much better for f(m) = 10 than for f(m) = 2 Hz. Additional tests showed that most HI subjects could discriminate temporal fine structure (TFS) at 800 Hz. The results are consistent with the idea that, for f(m) = 2 Hz and f(c) = 1000 Hz, frequency modulation (FM) detection was partly based on the use of TFS information. For higher carrier frequencies and for all carrier frequencies with f(m) = 10 Hz, FM detection was probably based on place cues.     

Electric quadrupole moments of the D states of alkaline-earth-metal ions

The electric quadrupole moment for the 4d(2)D(5/2) state of (88)Sr(+); one of the most important candidates for an optical clock, has been calculated using the relativistic coupled-cluster theory. This is the first application of this theory to determine atomic electric quadrupole moments. The result of the calculation is presented and the important many-body contributions are highlighted. The calculated electric quadrupole moment is (2.94 +/- 0.07)ea(2)(0), where a(o) is the Bohr radius and the electronic charge while the measured value is (2.6 +/- 0.3) ea(2)(0). This is so far the most accurate determination of the electric quadrupole moment for the above mentioned state. We have also calculated the electric quadrupole moments for the metastable 4d(2)D(3/2) state of 88(Sr(+) and for the 3d(2)D(3/2.5/2) and 5d(2)D(3/2.5/2) states of (43)Ca(+) and (138)Ba(+), respectively.     

Mechanisms underlying the detection of frequency modulation

Frequency modulation detection limens (FMDLs) were measured for carrier frequencies (f(c)) of 1000, 4000, and 6000 Hz, using modulation frequencies (f(m)) of 2 and 10 Hz and levels of 20 and 60 dB sensation level (SL), both with and without random amplitude modulation (AM), applied in all intervals of a forced-choice trial. The AM was intended to disrupt excitation-pattern cues. At 60 dB SL, the deleterious effect of the AM was smaller for f(m) = 2 than for f(m) = 10 Hz for f(c) = 1000 and 4000 Hz, respectively, while for f(c) = 6000 Hz the deleterious effect was large and similar for the two values of f(m). This is consistent with the idea that, for f(c) below about 5000 Hz and f(m) = 2 Hz, frequency modulation can be detected via changes in phase locking over time. However, at 20 dB SL, the deleterious effect of the added AM for f(c) = 1000 and 4000 Hz was similar for the two values of f(m), while for f(c) = 6000 Hz, the deleterious effect of the AM was greater for f(m) = 10 than for f(m) = 2 Hz. It is suggested that, at low SLs, the auditory filters become relatively sharp and phase locking weakens, so that excitation-pattern cues influence FMDLs even for low f(c) and low f(m).     

Q value of the superallowed decay of 46V and its influence on Vud and the unitarity of the Cabibbo-Kobayashi-Maskawa matrix

The masses of the radioactive nuclei (46)V and its decay daughter (46)Ti have been measured with the Canadian Penning Trap on-line Penning trap mass spectrometer to a precision of 1 x 10(-8). A Q(EC) value of 7052.90(40) keV for the superallowed beta decay of (46)V is obtained from the difference of these two masses. With this precise Q value, the Ft value for this decay is determined with improved precision. An investigation of an earlier Q-value measurement for (46)V uncovers a set of 7 measurements that cannot be reconciled with modern data and affects previous evaluations of V(ud) from superallowed Fermi decays. A new evaluation, adding our new data and removing the discredited subset, yields new values for G(V) and V(ud). When combined with recent results for V(us), this yields modified constraints for the unitarity of the Cabibbo-Kobayashi-Maskawa matrix and other extensions of the standard model.     

Evaluation of the role of magnetization transfer imaging in prostate: a preliminary study

Results of the preliminary study on the evaluation of the role of magnetization transfer imaging (MTI) of prostate in men who had raised prostate-specific antigen (PSA) (>4 ng/ml) or abnormal digital rectal examination (DRE) are reported. MT ratio (MTR) was calculated for 20 patients from the hyper- (normal) and hypo-intense regions (area suspicious of malignancy as seen on T2-weighted MRI) of the peripheral zone (PZ) and the central gland (CG) at 1.5 T. In addition, MTR was calculated for three healthy controls. Mean MTR was also calculated for the whole of the PZ (including hyper- and hypo-intense area) in all patients. Out of 20 patients, biopsy revealed malignancy in 12 patients. Mean MTR value (8.29+/-3.49) for the whole of the PZ of patients who were positive for malignancy on biopsy was statically higher than that observed for patients who were negative for malignancy (6.18+/-3.15). The mean MTR for the whole of the PZ of controls was 6.18+/-1.63 and is similar to that of patients who were negative for malignancy. Furthermore, for patients who showed hyper- (normal portion) and hypo-intense (region suspicious of malignancy) regions of the PZ, the MTR was statistically significantly different. These preliminary results reveal the potential role of MT imaging in the evaluation of prostate cancer.     

Convenient approaches for the synthesis of gold nanowires by successive utilization of two kinds of reducing agents in the solution of hexadecyl-trimethylammonium bromide

In spite that several empirical approaches for the synthesis of gold nanowires have been reported, there still remains ambiguity and controversy for their mechanisms. In this study, we report very easy and highly-reproducible synthetic method of gold (Au) nanowires with the size and the length of 40–50 nm and several micrometers, respectively. The method includes an extremely higher concentration of hexadecyl-trimethylammonium bromide (CTAB) at room temperature. We successively used two kinds of reducing agents, firstly sodium borohydride for the reduction of Au(III) ion into mostly Au(I) ion, and secondly triethylamine (TEA) leading Au(I) ion to Au(0) and its growth to Au nanowires. The former should be added very slowly, while the latter at once. Effects of oxygen were crucial for the growth to nanowires, and copper ion was quite effective for reductive scavenging of unwanted oxygen. It is strongly suggested that Cu(I) ion first generates the complex with TEA and then reduces Au(I) ion to Au(O). Thus, the Au nanowires grow in higher concentrations of Cu(I) ion. The concentration of CTAB was also found to be very important for the generation of Au nanowires.     

Search for lepton-flavor-violating decays of the neutral kaon

The Fermilab KTeV experiment has searched for lepton-flavor-violating decays of the K(L) meson in three decay modes. We observe no events in the signal region for any of the modes studied, and we set the following upper limits for their branching ratios at the 90% C.L.: BR(K(L) --> pi(0) micro(+/-) e(-/+)) <7.6 x 10(-11); BR(K(L) --> pi(0)pi(0) micro(+/-) e(-/+)) <1.7 x 10(-10); BR(pi(0) --> micro(+/-) e(-/+)) <3.6 x 10(-10). This result represents a factor of 82 improvement in the branching ratio limit for K(L) --> pi(0) micro(+/-) e(-/+) and is the first reported limit for K(L) --> pi(0)pi(0) micro(+/-) e(-/+).     

Further consideration of the correlation of the rates of solvolytic displacement of chloride ion from phosphorus (V)

Specific rates of solvolysis of diphenyl ( 1 ) and bis(2,4‐dichlorophenyl) ( 3 ) phosphorochloridate (chlorophosphate) have been determined by a conductivity technique. The available specific rates together with those determined earlier for bis(4‐chlorophenyl) phosphorochloridate ( 2 ) have been analyzed in terms of the extended (two‐term) Grunwald–Winstein equation. It is found that rather poor overall correlations found earlier for 1 and 2 and now for 3 are considerably improved when data points for 2,2,2‐trifluoroethanol–ethanol and acetone–water mixtures are excluded. The large sensitivities toward changes in solvent nucleophilicity are consistent with a bimolecular process. The differences in nucleophilicity of an acetone–water mixture for attack at carbon or at phosphorus are discussed. Copyright © 2010 John Wiley & Sons, Ltd.     

Collisional properties of cold spin-polarized metastable neon atoms

We measure the rates of elastic and inelastic two-body collisions of cold spin-polarized neon atoms in the metastable 3P2 state for 20Ne and 22Ne in a magnetic trap. From particle loss, we determine the loss parameter of inelastic collisions beta=6.5(18) x 10(-12) cm(3) s(-1) for 20Ne and beta=1.2(3) x 10(-11) cm(3) s(-1) for 22Ne. These losses are caused by ionizing (i.e., Penning) collisions and occur less frequently than for unpolarized atoms. This proves the suppression of Penning ionization due to spin polarization. From cross-dimensional relaxation measurements, we obtain elastic scattering lengths of a=-180(40)a(0) for 20Ne and a = +150(+80)(-50)a(0) for 22Ne, where a(0)=0.0529 nm.     

Exploring the additivity of binaural and monaural masking release

Experiment 1 examined comodulation masking release (CMR) for a 700-Hz tonal signal under conditions of N(o)S(o) (noise and signal interaurally in phase) and N(o)S(π) (noise in phase, signal out of phase) stimulation. The baseline stimulus for CMR was either a single 24-Hz wide narrowband noise centered on the signal frequency [on-signal band (OSB)] or the OSB plus, a set of flanking noise bands having random envelopes. Masking noise was either gated or continuous. The CMR, defined with respect to either the OSB or the random noise baseline, was smaller for N(o)S(π) than N(o)S(o) stimulation, particularly when the masker was continuous. Experiment 2 examined whether the same pattern of results would be obtained for a 2000-Hz signal frequency; the number of flanking bands was also manipulated (two versus eight). Results again showed smaller CMR for N(o)S(π) than N(o)S(o) stimulation for both continuous and gated masking noise. The CMR was larger with eight than with two flanking bands, and this difference was greater for N(o)S(o) than N(o)S(π). The results of this study are compatible with serial mechanisms of binaural and monaural masking release, but they indicate that the combined masking release (binaural masking-level difference and CMR) falls short of being additive.     

Evaluation of Expansion Coefficients from Optimal Fitting Parameters for the Analysis of Spectra of Diatomic Molecules and an Application to LiH

To evaluate individual expansion coefficients composing fitting parameters of the Born-Oppenheimer corrections to Dunham's coefficients Y(ij) that have been given analytically with the Delta(B) and Delta(omega) formalism, we examined the consistency of analytic expressions for those corrections with Watson's assertion of the experimental inseparability of nonadiabatic corrections Q(a, b)(r) for a molecule AB. Derived analytic expressions in terms of optimal fitting parameters for the corrections are essential to evaluate individual expansion coefficients. These expressions also reveal redundancies between empirical correction parameters Delta(ij). A method of evaluating nonadiabatic vibrational corrections Q(a, b)(r) and adiabatic corrections S(a, b)(r) separately consistent with Watson's assertion of inseparability is presented and is applied to an analysis of spectral data of LiH. Functions Q(a, b) and S(a, b) for LiH are thus successfully evaluated; S(H, Li)(r) values agree well with those predicted simply by wobble-stretch theory. Experimental values for optimal fitting parameters r(H)(1q) and r(H)(2q) are nearly equal to those of r(Li)(1q) and r(Li)(2q), respectively, in agreement with a theoretical relation r(a)(iq)=r(b)(iq). Copyright 2001 Academic Press.     

Effect of power densities and irradiation times on the degree of conversion and temperature increase of a microhybrid dental composite resin

The different parameters used for the photoactivation process provide changes in the degree of conversion (DC%) and temperature rise (TR) of the composite resins. Thus, the purpose of this study was to evaluate the DC (%) and TR of the microhybrid composite resin photoactivated by a new generation LED. For the KBr pellet technique, the composite resin was placed into a metallic mould (1-mm thickness and 4-mm diameter) and photoactivated as follows: continuous LED LCU with different power density values (50–1000 mW/cm²). The measurements for the DC (%) were made in a FTIR Spectrometer Bomen (model MB-102, Quebec-Canada). The spectroscopy (FTIR) spectra for both uncured and cured samples were analyzed using an accessory for the diffuse reflectance. The measurements were recorded in the absorbance operating under the following conditions: 32 scans, 4-cm^?1 resolution, and a 300 to 4000-cm^?1 wavelength. The percentage of unreacted carbon-carbon double bonds (% C=C) was determined from the ratio of the absorbance intensities of aliphatic C=C (peak at 1638 cm^?1) against an internal standard before and after the curing of the specimen: aromatic C-C (peak at 1608 cm^?1). For the TR, the samples were made in a metallic mould (2-mm thickness and 4-mm diameter) and photoactivated during 5, 10, and 20 s. The thermocouple was attached to the multimeter to allow the temperature readings. The DC (%) and TR were calculated by the standard technique and submitted to ANOVA and Tukey’s test (p < 0.05). The degree of conversion values varied from 35.0 (±1.3) to 45.0 (±2.4) for 5 s, 45.0 (±1.3) to 55.0 (±2.4) for 10 s, and 47.0 (±1.3) to 52.0 (±2.4) for 20 s. For the TR, the values ranged from 0.3 (±0.01) to 5.4 (±0.11)°C for 5 s, from 0.5 (±0.02) to 9.3 (±0.28)°C for 10 s, and from 1.0 (±0.06) to 15.0 (±0.95)°C for 20 s. The power densities and irradiation times showed a significant effect on the degree of conversion and temperature rise.     

Improvement of the Spectroscopic Constants of the PF(A(3)Pi) State and Assignment of the PF(A-X) Transition Dipole Function

High-resolution laser-excitation spectra were acquired for the v'=3-7 levels of the PF(A(3)Pi(0,1,2)<--X(3)Sigma(-)) transition from PF(X(3)Sigma(-)) molecules generated in a discharge flow reactor. These results were combined with lower resolution excitation spectra for the v'=8-11 levels and with existing high-resolution data in the literature for v'=0 and 1 to assign improved spectroscopic constants for PF(A(3)Pi(0,1,2)). The abnormal vibrational energy level spacings for all spin components of the PF(A(3)Pi) state are evidence for a homogeneous interaction with another (3)Pi state. The Lambda-doublet separation in the PF((3)Pi(0)) substate increases with vibrational level, which is taken as evidence for interaction with the PF(b(1)Sigma(+)) state. Laser-induced fluorescence spectra from individual v'=0-5 levels were used to obtain vibrational band intensities of the A-X transition. The strong dependence of the transition dipole on the r-centroid is consistent with the reduction in the radiative lifetimes with increasing v' level. The similarity between the isovalent PF(A(3)Pi) and SO(A(3)Pi) states is noted and the bond dissociation energy of PF(X(3)Sigma(-)) is discussed. Copyright 2001 Academic Press.     

The Value of Information Searching against Fake News

Inspired by the Daley-Kendall and Goffman-Newill models, we propose an Ignorant-Believer-Unbeliever rumor (or fake news) spreading model with the following characteristics: (i) a network contact between individuals that determines the spread of rumors; (ii) the value (cost versus benefit) for individuals who search for truthful information (learning); (iii) an impact measure that assesses the risk of believing the rumor; (iv) an individual search strategy based on the probability that an individual searches for truthful information; (v) the population search strategy based on the proportion of individuals of the population who decide to search for truthful information; (vi) a payoff for the individuals that depends on the parameters of the model and the strategies of the individuals. Furthermore, we introduce evolutionary information search dynamics and study the dynamics of population search strategies. For each value of searching for information, we compute evolutionarily stable information (ESI) search strategies (occurring in non-cooperative environments), which are the attractors of the information search dynamics, and the optimal information (OI) search strategy (occurring in (eventually forced) cooperative environments) that maximizes the expected information payoff for the population. For rumors that are advantageous or harmful to the population (positive or negative impact), we show the existence of distinct scenarios that depend on the value of searching for truthful information. We fully discuss which evolutionarily stable information (ESI) search strategies and which optimal information (OI) search strategies eradicate (or not) the rumor and the corresponding expected payoffs. As a corollary of our results, a recommendation for legislators and policymakers who aim to eradicate harmful rumors is to make the search for truthful information free or rewarding.     

Diode-Laser Jet Spectra and Analysis of the nu(1) and nu(4) Fundamentals of CCl(3)F

High-resolution infrared spectra have been measured for mixtures of CCl(3)F in Ne, expanded in a supersonic planar jet. We present the first analysis for the nu(4) fundamental and a complete analysis for the nu(1) band. Accurate spectroscopic constants have been obtained for both the nu(1) fundamental of the most abundant isotopic species, C(35)Cl(3)F, C(35)Cl(2)(37)ClF, and C(35)Cl(37)Cl(2)F. With respect to an earlier work [M. Snels, A. Beil, H. Hollenstein, M. Quack, U. Schmidt, and F. D'Amato, J. Chem. Phys. 103, 8846-8853 (1995)], the observation of Q branches of the three most abundant isotopomers allowed for an unambiguous determination of the nu(1) band origins. The nu(4) fundamental has not been the subject of a high-resolution analysis up to now. The observation of high-resolution spectra of the central part of the band permitted the determination of band origin, rotational constants, and Coriolis constant for the symmetric-top species, C(35)Cl(3)F. Copyright 2001 Academic Press.     

Multispectral analysis of bone lesions in the hands of patients with rheumatoid arthritis

Quantitative measures of rheumatoid arthritis (RA) disease progression can provide valuable tools for evaluation of new treatments during clinical trials. In this study, a novel multispectral (MS) MRI analysis method is presented to quantify changes in bone lesion volume (DeltaBLV) in the hands of RA patients. Image registration and MS analysis were employed to identify MS tissue class transitions between two serial MRI exams. DeltaBLV was determined from MS class transitions between two time points. The following three classifiers were investigated: (a) multivariate Gaussian (MVG), (b) k-nearest neighbor (k-NN), and (c) K-means (KM). Unlike supervised classifiers (MVG, k-NN), KM, an unsupervised classifier, does not require labeled training data, resulting in potentially greater clinical utility. All MS estimates of DeltaBLV were linearly correlated (r(p)) with manual estimates. KM and k-NN estimates also exhibited a significant rank-order correlation (r(s)) with manual estimates. For KM, r(p) = 0.94 p < 0.0001, r(s) = 0.76 p = 0.002; for k-NN, r(p) = 0.86 p = 0.0001, r(s) = 0.69 p = 0.009; and for MVG, r(p) = 0.84 p = 0.0003, r(s) = 0.49 p = 0.09. Temporal classification rates were as follows: for KM, 90.1%; for MVG, 89.5%; and for k-NN, 86.7%. KM matched the performance of k-NN, offering strong potential for use in multicenter clinical trials. This study demonstrates that MS tissue class transitions provide a quantitative measure of DeltaBLV.     

吖啶橙-罗丹明B二聚体能量转移体系在DNA测定中的应用及机理研究

首次研究了吖啶橙 罗丹明B二聚体能量转移体系作为荧光探针用于DNA的测定 ,并对其机理进行了探讨。用于鲱鱼精DNA和小牛胸腺DNA的测定 ,线性范围分别为 0 33～ 1 33mg·L- 1 ,0 33～ 3 33mg·L- 1 ,检测限分别为 1 6 3× 10 - 3mg·L- 1 ,1 5 2× 10 - 3mg·L- 1 。对 1 0 0mg·L- 1 鲱鱼精DNA和小牛胸腺DNA的测定 ,相对标准偏差分别为 2 4 %和 2 0 %。     

Localization and Environment of Tryptophans in Different Structural States of Concanavalin A

We have investigated the localization and environment of tryptophan residues in different quaternary and conformational states (tetrameric, dimeric, monomeric and unfolded) of metallized and demetallized concanavalin A (ConA) by selective chemical modification, fluorescence, and phosphorescence. ConA has four tryptophan residues (Trp 40, Trp 88, Trp 109 and Trp 182) per subunit. The pattern of oxidation by N-bromosuccinimide (NBS) shows that NBS modifies, in dimer, only Trp 182 which remains inaccessible in tetramer, two (Trp 88 along with Trp 182) in monomer, all four in unfolded form in presence of EDTA, and three (possibly Trp 40 along with Trp 88 and Trp 182) in unfolded form from native or remetallized ConA. Utilizing wavelength-selective fluorescence approach, we have observed a red edge excitation shift (REES) of 6–8 nm for tetramer and dimer. A more pronounced REES (11 nm) is observed for oxidized monomer compared to REES (3 nm) for unoxidized species. Acrylamide quenching shows the Stern-Volmer constant (K_SV) for dimer, monomer, unfolded ConA and unfolded apo-ConA being 3.8, 5.2, 12.8, 14.0 M⁻¹, respectively. Phosphorescence studies at 77 K give more structured spectra, with two (0,0) bands at 406.2 (weak) and 413.2 nm for tetramer. However, a single (0,0) band appears at 413.2 for dimer and 412.6 nm for monomer, while the (0,0) band of the oxidized monomer is red shifted to 414.4 nm. These results may provide important insight into subtlety of organization and environment of tryptophans in the context of folding and structural studies of oligomeric proteins including lectins.     

Stagnation pressure of imploding shells and ignition energy scaling of inertial confinement fusion targets

The stagnation pressure p(s) of imploding cylindrical ( n = 2) and spherical ( n = 3) shells is found to scale as p(s)/p(0)~M(2(n+1)/(gamma+1))(0), where M0 is the Mach number of the imploding shell and p(0) its maximum pressure. The result holds approximately for Mach numbers in the range 2相似文献   

Evidence of two dimensionality in quasi-one-dimensional cobalt oxides

The quasi-one-dimensional (Q1D) cobalt oxides A(N + 2)Co(n + 1)O(3n + 3) (A = Ca, Sr, and Ba, n = 1 - infinity) were investigated by muon-spin spectroscopy under applied pressures of up to 1.1 GPa. The relationship between the onset Néel temperature T(on)(N) and the interchain distance (d(ic)), which increases monotonically with n, is well fitted by the formula T(N)/T(N,0) = (1 - d(ic)/d(ic,o)(beta), here for T(on)(N) approximately 100 K for Ca(3)Co(2)O(6) (n = 1) and approximately 15 for BaCoCoO(3) (n = infinity at ambient P. The T(on)(N) - d(ic) curve also predicts a large dependence of Y(N) for the compounds with n > or = 5, i.e., in the vicinity of , while the compounds show only a very small effect. Indeed, our high-pressure mu(+) results show that of BaCoO(3) is enhanced by with a slope of 2.2 K(Gpa), whereas no detectable changes by P for both Ca(3)Co(2)O(6) and Sr(4)Co(3)O(9) (n = 2). This clearly confirms the role of the 2D-antiferromagnetic interaction on T(on)(N) in the Q1D cobalt oxides.