Effects of level and frequency on the audibility of partials in inharmonic complex tones

The effect of level and frequency on the audibility of partials was measured for complex tones with partials uniformly spaced on an equivalent rectangular bandwidth (ERB(N)) number scale. On each trial, subjects heard a sinusoidal "probe" followed by a complex tone. The probe was mistuned downwards or upwards (at random) by 4.5% from the frequency of one randomly selected partial in the complex. The subject indicated whether the probe was higher or lower in frequency than the nearest partial in the complex. The frequencies were roved from trial to trial, keeping frequency ratios fixed. In experiment 1, the level per partial, L, was 40 or 70 dB SPL and the mean frequency of the central partial, f(c), was 1201 Hz. Scores for the highest and lowest partials in the complexes were generally high for all spacings. Scores for the inner partials were close to chance at 0.75-ERB(N) spacing, and improved as the spacing was increased up to 2 ERB(N). For intermediate spacings, performance was better for the lower level used. In experiment 2, L was 70 dB SPL and f(c) was 3544 Hz. Performance worsened markedly for partial frequencies above 3544 Hz, consistent with a role of phase locking.     

Influence of surface area on charge transport and recombination in dye-sensitized TiO2 solar cells

The dependence of the electron transport and recombination dynamics on the internal surface area of mesoporous nanocrystalline TiO2 films in dye-sensitized solar cells was investigated. The internal surface area was varied by altering the average particle size in the films. The scaling of the photoelectron density and the electron diffusion coefficient at short circuit with internal surface area confirms the results of a recent study (Kopidakis, N.; Neale, N. R.; Zhu, K.; van de Lagemaat, J.; Frank, A. J. Appl. Phys. Lett. 2005, 87, 202106) that transport-limiting traps are located predominately on the surfaces of the particles. The recombination current density was found to increase superlinearly (with an exponent of 1.40 +/- 0.12) with the internal surface area. This result is at odds with the expected linear dependence of the recombination current density on the surface area when only the film thickness is increased. The observed scaling of the recombination current density with surface area is consistent with recombination being transport-limited. Evidence is also presented confirming that photoinjected electrons recombine with redox species in the electrolyte via surface states rather than from the TiO2 conduction band.     

Differential proteome analysis of colon carcinoma cell line SW480 after reconstitution of the tumour suppressor Smad4

The tumour suppressor gene Smad4 is frequently inactivated in gastrointestinal carcinomas. Smad4 plays a pivotal role in transducing signals of the transforming growth factor-β (TGF-β) superfamily of proteins. Inactivation of Smad4 seems to occur late during tumour progression when tumours acquire invasive and metastatic properties. Identification of proteins directly or indirectly regulated by Smad4 would, therefore, ease the future design of new diagnostic and therapeutic strategies for gastrointestinal carcinoma. We have used human colon carcinoma cell line SW480 stably transfected with Smad4 as an in-vitro model system to identify Smad4-regulated proteins by applying two-dimensional gel electrophoresis (2DE) then MALDI-PMF/PFF-MS. We identified a total of 47 protein species with a Smad4-dependent expression. From the functions of the candidate proteins we obtained new insights into Smad4’s participation in processes, for example apoptosis, differentiation, and proliferation.     

Effect of temperature programmes on protein crystallisation

Varying the temperature has been proven to be beneficial for improving the screening efficiency of protein crystallisation, and thus a crystallisation screening strategy based on this phenomenon can be developed. Such a temperature varying strategy can be applied in practical crystallisation screening, however, there are no guidelines for determining what temperature programme should be utilised. It is therefore necessary to investigate how the temperature programme affects the crystallisation process, so as to help people design a suitable temperature programme. For this purpose, we investigated the effect of temperature programmes on the protein crystallisation (lysozyme, proteinase K, and concanavalin A) that are characterised by different solubility behaviours with respect to temperature. Judging from the reproducibility studies of protein crystallisation with different temperature programmes, we recommend using linear temperature programmes for a moderate time period (24 to 48 h) and a large temperature range according to the properties of the proteins. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Trigger efficiencies at BESⅢ

Trigger efficiencies at BESⅢ were determined for both the J/ψ and ψ＇ data taking of 2009. Both dedicated runs and physics datasets are used; efficiencies are presented for Bhabha-scattering events, generic hadronic decay events involving charged tracks, dimuon events and ψ＇→π＋π-J/ψ, J/ψ→ 1＋1- events.The efficiencies are found to lie well above 99% for all relevant physics cases, thus fulfilling the BESⅢ design specifications.     

127I NQR and 1H NMR studies of 4-aminopyridinium tetraiodoantimonate(III); molecular motion and phase transition

The crystals of 4-NH₂PyHSbI₄ (Py = C₅H₄N) have been investigated by means of ¹²⁷I NQR, ¹H NMR T ₁ and DTA. The crystals can exist in two modifications of β and α(I) at room temperatures. The α(I)-phase is a metastable state which is obtained when the stable β form is heated. The α(I)-phase undergoes a first-order type phase transition of α(I) $\leftrightarrow \alpha $ (II) at 272 K (on heating), while the β-phase is stable down to 77 K. Four and two ¹²⁷I (m = ±1/2 $\leftrightarrow \pm $ 3/2) NQR lines have been found for the β- and α(II)-phases, respectively. One half of them is assignable to the terminal I atom(s) and the other to the bridging I atom(s) in each phase. All the resonance lines of the α(II)-phase underwent a disappearance above ca. 240 K and no resonance line was observed in the α(I)-phase. The second moment M ₂ value of ¹H NMR spectra with 8 G² at 290 K shows that the 4-NH₂PyH^?+? cations reside in the rigid lattice in the β-phase. In contrast, in the α(I)-phase the cation rotates about an axis more symmetric than pseudo threefold axis. The activation energy of 21 kJ mol^???1 was estimated for the reorientational motion in the α(I)-phase from the ¹H NMR T ₁ measurements. The nature of phase transitions in the 4-NH₂PyHSbI₄ is discussed in comparison with that in 4-NH₂PyHSbBr₄.     

Low temperature fired Ni-Cu-Zn ferrite with Bi4Ti3O12

The Ni-Cu-Zn ferrites with different contents of Bi₄Ti₃O₁₂ ceramics (1-8 wt%) as sintering additives were prepared by the usual ceramic technology and sintered at 900 °C to adapt to the low temperature co-fired ceramic (LTCC) technology. The magnetic and dielectric properties of the ferrite can be effectively improved with the effect of an appropriate amount of Bi₄Ti₃O₁₂. For all samples, the ferrite sintered with 2 wt% Bi₄Ti₃O₁₂ has relatively high density (98.8%) and permeability, while the ferrite with 8 wt% Bi₄Ti₃O₁₂ has relatively good dielectric properties in a wide frequency range. The influences of Bi₄Ti₃O₁₂ addition on microstructure, magnetic and dielectric properties of the ferrite have been discussed.     

Ca(BH4)2络合物电子结构及热力学稳定性的第一性原理研究

利用第一性原理研究了低温及高温相Ca(BH4)2络合物的电子结构、晶格振动及其反应焓。计算结果表明：低温及高温相Ca(BH4)2中Ca+2与[BH4]－以离子键形式相结合,[BH4]－离子中B原子和H原子以共价键形式相结合,对该共价键有贡献的主要是B原子的2p轨道电子,H原子的1s轨道电子。Ca(BH4)2可能的反应路径为：Ca(BH4)2→2CaH2+CaB6+10H2,该反应在300K下反应焓为43.22 kJ/mol H2。拉伸B—H键所对应的声子频率较高,其值为2360～2500cm-1,这可能是导致B—H键断裂释放氢气需要较高温度的主要原因之一。     

基于脉冲耦合神经网络的拉曼光谱定性分析

通过对脉冲耦合神经网络(pulse coupled neural network,PCNN)和拉曼光谱定性分析的研究,提出了基于PCNN的拉曼光谱定性分析方法.首先,利用PCNN神经元的疲劳与不应期特性将拉曼光谱数据进行编码;然后,基于改进的Horspool算法将检测样品对应编码与基码数据库中的所有基码逐一匹配,并得到各对应的匹配相似度,进而判定样品类别.相关实验和数据分析证明了该文方法的准确性和有效性.同时,该文方法避免了目前基于谱模版定性分析方法中待测样品拉曼光谱特征谱峰难以确定以及匹配分析冗余度高等不足,且对存储空间的要求仅为后者的5.8%.