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Author(s):  
Chieh Kao ◽  
Maria D. Sera ◽  
Yang Zhang

Purpose: The aim of this study was to investigate infants' listening preference for emotional prosodies in spoken words and identify their acoustic correlates. Method: Forty-six 3- to-12-month-old infants ( M age = 7.6 months) completed a central fixation (or look-to-listen) paradigm in which four emotional prosodies (happy, sad, angry, and neutral) were presented. Infants' looking time to the string of words was recorded as a proxy of their listening attention. Five acoustic variables—mean fundamental frequency (F0), word duration, intensity variation, harmonics-to-noise ratio (HNR), and spectral centroid—were also analyzed to account for infants' attentiveness to each emotion. Results: Infants generally preferred affective over neutral prosody, with more listening attention to the happy and sad voices. Happy sounds with breathy voice quality (low HNR) and less brightness (low spectral centroid) maintained infants' attention more. Sad speech with shorter word duration (i.e., faster speech rate), less breathiness, and more brightness gained infants' attention more than happy speech did. Infants listened less to angry than to happy and sad prosodies, and none of the acoustic variables were associated with infants' listening interests in angry voices. Neutral words with a lower F0 attracted infants' attention more than those with a higher F0. Neither age nor sex effects were observed. Conclusions: This study provides evidence for infants' sensitivity to the prosodic patterns for the basic emotion categories in spoken words and how the acoustic properties of emotional speech may guide their attention. The results point to the need to study the interplay between early socioaffective and language development.


2022 ◽  
Vol 14 (2) ◽  
pp. 283
Author(s):  
Biao Qi ◽  
Longxu Jin ◽  
Guoning Li ◽  
Yu Zhang ◽  
Qiang Li ◽  
...  

This study based on co-occurrence analysis shearlet transform (CAST) effectively combines the latent low rank representation (LatLRR) and the regularization of zero-crossing counting in differences to fuse the heterogeneous images. First, the source images are decomposed by CAST method into base-layer and detail-layer sub-images. Secondly, for the base-layer components with larger-scale intensity variation, the LatLRR, is a valid method to extract the salient information from image sources, and can be applied to generate saliency map to implement the weighted fusion of base-layer images adaptively. Meanwhile, the regularization term of zero crossings in differences, which is a classic method of optimization, is designed as the regularization term to construct the fusion of detail-layer images. By this method, the gradient information concealed in the source images can be extracted as much as possible, then the fusion image owns more abundant edge information. Compared with other state-of-the-art algorithms on publicly available datasets, the quantitative and qualitative analysis of experimental results demonstrate that the proposed method outperformed in enhancing the contrast and achieving close fusion result.


2022 ◽  
Vol 10 (1) ◽  
Author(s):  
Gabriela Vyskočilová ◽  
Cristina Carşote ◽  
Richard Ševčík ◽  
Elena Badea

AbstractIn this study we used an analytical approach based on complementary techniques that targets all structural levels of collagen in leather to investigate how vegetable-tanned leather deteriorates during soil burial tests. For the first time, a group of deterioration markers specific to molecular, fibrillar and fibrous structure of collagen in leather was associated with the deterioration of buried leather. The application of the second order derivative of FTIR-ATR spectra analysis allowed us to detect loosening of collagen–tannin matrix, de-tanning and gelatin formation based on the behaviour of collagen and tannin spectral components (intensity variation and shifts). Collagen denaturation observed by DSC analysis and its thermo-oxidative behaviour measured by TG/DTG analysis, as well as the altered morphology of collagen (namely melt-like fibres and distorted fibrillar ultrastructure) imaged by SEM confirmed the FTIR-ATR analyis results. These analytical outcomes enabled us to understand the effect of leather hardening/cementing through soil mineral penetration into its fibrous structure and thus correctly interprete the higher-than-expected shrinkage temperatures and intervals determinatd by MHT method. Thus, MHT method proved to be suitable for a quick evaluation method that can direcly support the first conservation decision after excavation. The combination of FTIR-ATR, DSC, TG/DTG and SEM can be particularly useful to provide insights on the deterioration mechanism of archaeological leather and support best decision on its long-term preservation.


2022 ◽  
Vol 2022 ◽  
pp. 1-12
Author(s):  
Muhammad Hameed Siddiqi ◽  
Amjad Alsirhani

Most medical images are low in contrast because adequate details that may prove vital decisions are not visible to the naked eye. Also, due to the low-contrast nature of the image, it is not easily segmented because there is no significant change between the pixel values, which makes the gradient very small Hence, the contour cannot converge on the edges of the object. In this work, we have proposed an ensembled spatial method for image enhancement. In this ensembled approach, we first employed the Laplacian filter, which highlights the areas of fast intensity variation. This filter can determine the sufficient details of an image. The Laplacian filter will also improve those features having shrill disjointedness. Then, the gradient of the image has been determined, which utilizes the surrounding pixels for the weighted convolution operation for noise diminishing. However, in the gradient filter, there is one negative integer in the weighting. The intensity value of the middle pixel might be deducted from the surrounding pixels, to enlarge the difference between the head-to-head pixels for calculating the gradients. This is one of the reasons due to which the gradient filter is not entirely optimistic, which may be calculated in eight directions. Therefore, the averaging filter has been utilized, which is an effective filter for image enhancement. This approach does not rely on the values that are completely diverse from distinctive values in the surrounding due to which it recollects the details of the image. The proposed approach significantly showed the best performance on various images collected in dynamic environments.


2022 ◽  
Vol 302 ◽  
pp. 114095
Author(s):  
Pengtao Gao ◽  
Liang Guo ◽  
Mengchun Gao ◽  
Yangguo Zhao ◽  
Chunji Jin ◽  
...  

Author(s):  
Sahana Vasudevan ◽  
Parthasarathy Srinivasan ◽  
Prasanna Neelakantan ◽  
John Bosco Balaguru Rayappan ◽  
Adline Princy Solomon

Currently available diagnostic procedures for infections are laborious and time-consuming, resulting in a substantial financial burden by increasing morbidity, increased costs of hospitalization, and mortality. Therefore, innovative approaches to design diagnostic biomarkers are imperative to assist in the rapid and sensitive diagnosis of microbial infections. Acyl homoserine lactones (AHLs) are ubiquitous bacterial signaling molecules that are found to be significantly upregulated in infected sites. In this pioneering work, we have developed a simple photoluminescence-based assay using cysteamine-capped titanium oxide (TiO2) nanoparticles for AHL detection. The PL intensity variation of the oxygen defect state of TiO2 was used for the biosensing measurements. The bioassays were validated using two well-studied AHL molecules (C4-HSL and 3-oxo-C12 HSL) of an important human pathogen, Pseudomonas aeruginosa. The developed system has a maximum relative response of 98%. Furthermore, the efficacy of the system in simulated host urine using an artificial urine medium showed a linear detection range of 10–160 nM. Also, we confirmed the relative response and specificity of the system in detecting AHLs produced by P. aeruginosa in a temporal manner.


Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 7848
Author(s):  
Vitorino Biazi ◽  
Letícia Avellar ◽  
Anselmo Frizera ◽  
Arnaldo Leal-Junior

Shape reconstruction is growing as an important real-time monitoring strategy for applications that require rigorous control. Polymer optical fiber sensors (POF) have mechanical properties that allow the measurement of large curvatures, making them appropriate for shape sensing. They are also lightweight, compact and chemically stable, meaning they are easy to install and safer in risky environments. This paper presents a sensor system to detect angles in multiple planes using a POF-intensity-variation-based sensor and a procedure to detect the angular position in different planes. Simulations are performed to demonstrate the correlation between the sensor’s mechanical bending response and their optical response. Cyclic flexion experiments are performed at three test frequencies to obtain the sensitivities and the calibration curves of the sensor at different angular positions of the lateral section. A Fast Fourier Transform (FFT) analysis is tested as a method to estimate angular velocities using POF sensors. The experimental results show that the prototype had high repeatability since its sensitivity was similar using different test frequencies at the same lateral section position. The proposed approach proved itself feasible considering that all linear calibration curves presented a coefficient of determination (R2) higher than 0.9.


NIR news ◽  
2021 ◽  
pp. 096033602110609
Author(s):  
Krzysztof B Beć

Between 18 and 21 October 2021, the 20th International Conference on NIR spectroscopy in Beijing took place. Despite this time being held as a virtual event, it was a highly successful symposium met with high interest from the wide audience – as evidenced by many excellent presentations, around which numerous vivid discussions developed. During the conference, four workshops were offered, focused at discussing few areas essential for NIR spectroscopy and its applications. Excellent workshops were provided by Professors Heinz Siesler, Hui Yan, Dolores Pérez-Marín and Tom Fearn, in which invaluable knowledge was shared with the participants of the conference. Among these renowned experts, I had the honour to offer my contribution with the workshop aimed at the physicochemical foundations of NIR spectroscopy, an area that seldom is exhaustively presented in the textbooks. The workshop aimed at shedding light on the complex world of overtone and combination bands and was met with a considerable interest from the participants. As many questions have been asked both during the dedicated Q&A session, as well as through other channels and private correspondence, I would like to provide a short recapitulation of the workshop in the form of this brief article. Some of the most essential ‘take home messages’, such as the origin of the intensity variation of the overtone bands and the famous ‘selection rule’ of the harmonic oscillator, among others will be briefly outlined here.


2021 ◽  
Author(s):  
Bo Liu ◽  
Kun Yang ◽  
Siyu Lu ◽  
Junjie Cai ◽  
Fan Li ◽  
...  

Abstract A novel method for the detection of procalcitonin in a homogeneous system by matched carbon dots (CDs) labeled immunoprobes was proposed based on the principle of FRET and double antibody sandwich method. Blue-emitting carbon dots with a strong fluorescence emission range of 400-550nm and red-emitting carbon dots with the best excitation range of 410-550nm were prepared before they reacted with procalcitonin protoclone antibody pairs to form immunoprobes. According to the principles of FRET, blue-emitting carbon dots were selected as the energy donor and red-emitting carbon dots as the energy receptor. The external light source excitation (310nm) could only cause weak luminescence of CDs. However, once procalcitonin was added, procalcitonin and antibodies would be combined with each other quickly (≤ 20 min). Here, blue-emitting carbon dots acquired energy could be transferred to red-emitting carbon dots efficiently, causing the emitted fluorescence enhancement of red-emitting carbon dots. The fluorescence detection results in PBS buffer solution and diluted rabbit blood serum showed that the fluorescence intensity variation was linear with the concentration of procalcitonin. There was a good linear relationship between F/F0 and procalcitonin concentrations in PBS buffer solution that ranged from 0 to 100ng/ml, and the linear equation was F/F0 = 0.004 * Cpct + 0.98359. Detection in the diluted rabbit serum led to the results that were linear in two concentration ranges, including 0-40ng/ml and 40-100ng/ml, and the detection limit based on 3σ/K was 0.52ng/ml. It’s likely that this matched CDs labeled immunoprobes system can provide a new mode for rapid homogeneous detection of disease markers.


Nanophotonics ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Zixuan Zhang ◽  
Xuefan Yin ◽  
Zihao Chen ◽  
Feifan Wang ◽  
Weiwei Hu ◽  
...  

Abstract Phase-only light modulation is an important functionality for many optoelectronic applications. Although modulation efficiency can be significantly improved by using optical resonances, resonance detuning is always accompanied with dramatic intensity variation that is less ideal. Here, we propose a method to achieve intensity-flattened phase shifting by utilizing the unidirectional guided resonance (UGR) – a novel class of topologically enabled guided resonance that only radiates toward a single side. Consequently, the incident excites resonances and generates phase shifting, but it transmits to only one out-going port without other choice, which flattens the transmittance. Theory and simulation agree well and confirm our findings, in particular when nonradiative loss has been taken into account. By directly measuring the intensity and phase responses of UGR samples, a dip depth of 0.43 is observed with nonradiative Q around 2500. We further predict a dip depth of 0.13 can be achieved with a reasonable nonradiative Q around 8000 in state-of-art fabrication precision, which is sufficient and useful for the applications ranging from light projection, flat metalens optics, optical phased array, to light detection and ranging.


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