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To explore new kind of flexible transparent conductive oxide films for application in flexible optoelectronic devices, In-doped CdO thin films were synthesized by radio frequency magnetron sputtering on thin polyethylene terephthalate substrates at low temperature. The effects of growth time and temperature on the resistance and transmittance of In-doped CdO films were studied in detail for the first time. It is demonstrated that the sheet resistance of the film deposited at 100 °C for 20 min was 96.9 Ω/cm2 for the as-grown sample and increased about 6.4% after experienced 500 bending cycles. The results demonstrate that the In-doped CdO films possess not only excellent opto-electronic properties but also high mechanical stability. In-doped CdO films show great potential to be applied in wearable electronics, transparent devices, solar cells and so forth. [ABSTRACT FROM AUTHOR]

Transcription factor-driven cell fate engineering in pluripotency induction, transdifferentiation, and forward reprogramming requires efficiency, speed, and maturity for widespread adoption and clinical translation. Here, we used Oct4, Sox2, Klf4, and c-Myc driven pluripotency reprogramming to evaluate methods for enhancing and tailoring cell fate transitions, through directed evolution with iterative screening of pooled mutant libraries and phenotypic selection. We identified an artificially evolved and enhanced POU factor (ePOU) that substantially outperforms wild-type Oct4 in terms of reprogramming speed and efficiency. In contrast to Oct4, not only can ePOU induce pluripotency with Sox2 alone, but it can also do so in the absence of Sox2 in a three-factor ePOU/Klf4/c-Myc cocktail. Biochemical assays combined with genome-wide analyses showed that ePOU possesses a new preference to dimerize on palindromic DNA elements. Yet, the moderate capacity of Oct4 to function as a pioneer factor, its preference to bind octamer DNA and its capability to dimerize with Sox2 and Sox17 proteins remain unchanged in ePOU. Compared with Oct4, ePOU is thermodynamically stabilized and persists longer in reprogramming cells. In consequence, ePOU: 1) differentially activates several genes hitherto not implicated in reprogramming, 2) reveals an unappreciated role of thyrotropin-releasing hormone signaling, and 3) binds a distinct class of retrotransposons. Collectively, these features enable ePOU to accelerate the establishment of the pluripotency network. This demonstrates that the phenotypic selection of novel factor variants from mammalian cells with desired properties is key to advancing cell fate conversions with artificially evolved biomolecules. [ABSTRACT FROM AUTHOR]

The transcription factor Oct4 is a core component of molecular cocktails inducing pluripotent stem cells ( iPSCs), while other members of the POU family cannot replace Oct4 with comparable efficiency. Rather, group III POU factors such as Oct6 induce neural lineages. Here, we sought to identify molecular features determining the differential DNA-binding and reprogramming activity of Oct4 and Oct6. In enhancers of pluripotency genes, Oct4 cooperates with Sox2 on heterodimeric SoxOct elements. By re-analyzing Ch IP-Seq data and performing dimerization assays, we found that Oct6 homodimerizes on palindromic OctOct more cooperatively and more stably than Oct4. Using structural and biochemical analyses, we identified a single amino acid directing binding to the respective DNA elements. A change in this amino acid decreases the ability of Oct4 to generate iPSCs, while the reverse mutation in Oct6 does not augment its reprogramming activity. Yet, with two additional amino acid exchanges, Oct6 acquires the ability to generate iPSCs and maintain pluripotency. Together, we demonstrate that cell type-specific POU factor function is determined by select residues that affect DNA-dependent dimerization. [ABSTRACT FROM AUTHOR]

Successful operation of the Synchronous Overlap and Add (SOLA) algorithm for Time Scale Modification (TSM) of speech is closely tied to the proper choice of parameters. This paper investigates the quality of time scale modified speech under different values of primary parameters. Based on Mean Opinion Score (MOS) tests and Bark Spectral Distortion (BSD) measure, the proper choices of synthesis shift ( Ss) and the duration of the shift search interval ( Kmax ) are given experimentally. The conclusions can be helpful for operating the SOLA algorithm for time scale modification of speech. [ABSTRACT FROM AUTHOR]

A new family of windows is constructed by convolutions via a few rectangular windows with same time width and is thus referred to as convolution windows. The expressions of the second-order up to the eighth-order convolution windows in both the time and frequency domains are derived. Their applications in high accuracy harmonic analysis of periodic signals are investigated. Comparisons between the proposed windows and some known windows with the same width shows that, when the synchronous deviation of data sampling is slight, the proposed ones have the least effect of spectral leakage. Therefore, the new windows are well suited for high accuracy harmonic analysis and parameter estimation for periodic signals. The error analysis and computer simulations show that the estimation errors, corresponding to frequency, amplitude and phase of every harmonic component of a signal, are proportional to the pth power of the relative frequency deviation in case of the pth-order convolution window is applied to windowing signal of approximately p cycles. By introducing real time adjustment in sampling interval, the proposed algorithm can adaptively trace signal frequency and lead to less sampling synchronous deviation. The proposed approach has the advantages of easy implementation and high measure precision and can be used in harmonic analysis of quasi-periodic signals whose fundamental frequency drifts slowly with time. [ABSTRACT FROM AUTHOR]

Hiding efficiency of traditional audio information hiding methods is always low since the sentience similarity cannot be guaranteed. A new audio information hiding method is proposed in this letter which can impose the insensitivity with the audio phase for auditory and realize the information hiding through specific algorithm in order to modify local phase within the auditory perception. The algorithm is to introduce the operation of “set 1” and “set 0” for every phase vectors, then the phases must lie on the boundary of a phase area after modified. If it lies on “1” boundary, it comes by set 1 operation. If it lies on “0” boundary, it comes by set 0 operation. The results show that, compared with the legacy method, the proposed method has better auditory similarity, larger information embedding capacity and lower code error rate. As a kind of blind detect method, it fits for application scenario without channel interference. [ABSTRACT FROM AUTHOR]

The design and implementation of fast algorithms related to Elliptic Curve Cryptography (ECC) over the field GF( p), such as modular addition, modular subtraction, point addition, point production, choice of embedding plaintext to a point, etc. are given. A practical software library has been produced which supports variable length implementation of the ECC-based ElGamal cryptosystem. More importantly, this scalable architecture of the design enables the ECC being used in restricted platforms as well as high-end servers based on Intel Pentium CPU. Applications such as electronic commerce security, data encryption communication, etc. are thus made possible for real time and effective ECC. [ABSTRACT FROM AUTHOR]

The perceptual effect of the phase information in speech has been studied by auditory subjective tests. On the condition that the phase spectrum in speech is changed while amplitude spectrum is unchanged, the tests show that: (1) If the envelop of the reconstructed speech signal is unchanged, there is indistinctive auditory perception between the original speech and the reconstructed speech; (2) The auditory perception effect of the reconstructed speech mainly lies on the amplitude of the derivative of the additive phase; (3) t d is the maximum relative time shift between different frequency components of the reconstructed speech signal. The speech quality is excellent while t d <10ms; good while 10ms< t d<20ms; common while 20ms< t d<35ms, and poor while t d>35ms. [ABSTRACT FROM AUTHOR]

Oct4, along with Sox2 and Klf4 (SK), can induce pluripotency but structurally similar factors like Oct6 cannot. To decode why Oct4 has this unique ability, we compare Oct4-binding, accessibility patterns and transcriptional waves with Oct6 and an Oct4 mutant defective in the dimerization with Sox2 (Oct4defSox2). We find that initial silencing of the somatic program proceeds indistinguishably with or without Oct4. Oct6 mitigates the mesenchymal-to-epithelial transition and derails reprogramming. These effects are a consequence of differences in genome-wide binding, as the early binding profile of Oct4defSox2 resembles Oct4, whilst Oct6 does not bind pluripotency enhancers. Nevertheless, in the Oct6-SK condition many otherwise Oct4-bound locations become accessible but chromatin opening is compromised when Oct4defSox2 occupies these sites. We find that Sox2 predominantly facilitates chromatin opening, whilst Oct4 serves an accessory role. Formation of Oct4/Sox2 heterodimers is essential for pluripotency establishment; however, reliance on Oct4/Sox2 heterodimers declines during pluripotency maintenance. Oct4, along with Sox2 and Klf4 can induce pluripotency, but structurally similar factors like Oct6 cannot. Here, using pluripotency competent and incompetent factors, the authors show that Sox2 plays a dominant role in facilitating chromatin opening at Oct4 bound DNA early during reprogramming to pluripotency. [ABSTRACT FROM AUTHOR]