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Variation in voicing is common among sounds of the world's languages: sounds that are analyzed as voiceless can undergo voicing, and those analyzed as voiced can devoice. Among voiceless glottal sounds in particular, voicing is widespread: linguists often expect the voiceless glottal stop [ʔ] and fricative [h] to be fully voiced, especially between vowels. In this study, we use audio recordings from Illustrations of the International Phonetic Alphabet published in the Journal of the International Phonetic Association to explore the extent to which glottal consonants and non-modal (breathy and creaky) vowels differ in terms of percentage voicing and voicing intensity in three phrasal positions. We find that voiceless [h] is only slightly less voiced than voiced [ɦ] in initial position. Between two vowels, both [h] and [ɦ] are as voiced as breathy vowels. Glottal stops and creaky vowels are both characterized by high percentages of voicing, but they differ in voicing intensity: in all phrasal positions, glottal stops generally have periods of strong and weak voicing, whereas creaky vowels are strongly voiced. In contrast, vowels described as 'rearticulated', 'checked', or 'glottalized' show similar drops in voicing intensity to glottal stops. We interpret these results through an articulatory lens: glottal consonants and non-modal vowels are both modulations in phonation resulting from laryngeal constriction and vocal fold spreading. We argue further that, because voicing during [ʔ] and [h] is largely predictable from respiratory and prosodic constraints, many cases of [ʔ] and [h] can be considered phonetically underspecified for voicing. [ABSTRACT FROM AUTHOR]

We report a rapid synthesis method for producing CsSnCl3:Mn2+ perovskites, derived from SnF2, and investigate the effects of rapid thermal treatment on their photoluminescence properties. Our study shows that the initial CsSnCl3:Mn2+ samples exhibit a double luminescence peak structure with PL peaks at approximately 450 nm and 640 nm, respectively. These peaks originate from defect-related luminescent centers and the 4T1→6A1 transition of Mn2+. However, as a result of rapid thermal treatment, the blue emission is significantly reduced and the red emission intensity is increased nearly twofold compared to the pristine sample. Furthermore, the Mn2+-doped samples demonstrate excellent thermal stability after the rapid thermal treatment. We suggest that this improvement in photoluminescence results from enhanced excited-state density, energy transfer between defects and the Mn2+ state, as well as the reduction of nonradiative recombination centers. Our findings provide valuable insights into the luminescence dynamics of Mn2+-doped CsSnCl3 and open up new possibilities for controlling and optimizing the emission of rare-earth-doped CsSnCl3. [ABSTRACT FROM AUTHOR]

The inherent relationships between the surface phenomena and chemical structures of thermally modified bamboo were investigated to predict the intrinsic properties of bamboo during the thermal modification through the surface phenomena effectively. Moso bamboo was firstly treated by vacuum treatment at 150°C, 170°C, 190°C and 210°C for 1, 2, 3 and 4 h, respectively. And then the surface colour, contact angle and chemical compositions of heat-treated bamboo and in-situ chemical properties of the heat-treated cell wall were analysed by using the colour metre, contact angle metre and confocal scanning microscope. Results showed that the surface colour became darker and the hydrophobicity was increased after heat treatment. As compared to the control, the lightness (L*) value carried out in accordance with CIELAB of heat-treated bamboo decreased by almost 54% and the maximum increase of contact angle was 160%. The surface colour and contact angle of bamboo were closely related to the lignin content. The darkened colour and increased hydrophobicity of the bamboo surface were caused by the crack of C–O–C and the decrease of C=O in lignin. Furthermore, fluorescence analysis indicated that the lignin distribution in the cell wall increased gradually after heat treatment, especially in the thick-walled cells and the corners of cells. [ABSTRACT FROM AUTHOR]

This paper is aimed at the experimental study on mould contamination status. Mold contamination has seriously threatened residents’ physical and mental health and buildings. However, few experimental studies on mold contamination was made in the built environment under hot and humid climate. We firstly prepared the Sabaurauds agar(SAB) with reference to the national standard and set sampling points by the five-point sampling method in a classroom of USC. Then, we cultured the sample in 28 °C constant temperature condition, counted mould number with plate counting method and referred to the Omeilianski formula to calculate indoor mould concentration. The study found that the average concentration of mould spore in the typical public building was 629cfu/m3, and the exceeding rate was up to 25.8%. The results show that the typical public building environment in Hengyang has serious mould contamination, thus further environmental optimization research is urgently needed.

The micromechanics of wood cell walls and the bending properties of wood were investigated by using nanoindentation and macromechanical test machine at elevated temperature, respectively. The microstructure of wood at the temperatures ranged from 20 to 160°C was also observed by optical microscope and scanning electron microscope. Results indicated that the increased temperature accompanying with the moisture release affected the mechanical behavior of wood on both cell-wall level and macroscale. The cell wall's elastic modulus (Er) and hardness (H) decreased as temperature increased to 80°C due to the softening of wood polymers under hot and humid condition. On the contrary, both the Er and H increased when the temperature was above 100°C ascribed to the massive release of moisture. The increased mechanical properties of the thick-wall cells made a major contribution to the improved bending properties of wood at the macroscale. Furthermore, the cell walls at 80°C own the highest indentation creep ratio (CIT), that is, wood are easier to creep under a constant load. In hence, the mechanical stability of timber in constructions at about 80°C shall be paid more attention. [ABSTRACT FROM AUTHOR]

Background and Aims: The prognostic significance of combination of white blood cell (WBC) and D-dimer on acute ischemic stroke (AIS) remains to be explored. We aimed to investigate the combined effect of WBC and D-dimer levels on in-hospital outcomes of AIS patients.Methods and Results: 801 AIS patients were included. Patients were divided into four groups according to the cut-point identified by receiver operating characteristic (ROC) curve of D-dimer (1.105 μg/L) and WBC (7.05 × 109/L): LWLD (low WBC count and low D-dimer), LWHD (low WBC count and high D-dimer), HWLD (high WBC count and low D-dimer), and HWHD (high WBC count and high D-dimer). HWHD group had the highest cumulative incidence of in-hospital mortality (hazard ratio, 5.79; 95%CI, 1.71-19.58, P = 0.006). Patients in HWHD group were 4.14 fold more likely to have in-hospital pneumonia (odds ratio, 4.14; 95%CI, 2.09-8.21; P < 0.001), compared with those in LWLD group. The area under curve (AUC) of the combination of WBC and D-dimer levels for in-hospital mortality and pneumonia was larger than that of WBC and D-dimer alone (0.920 vs. 0.900 vs. 0.915; 0.831 vs. 0.829 vs. 0.807).Conclusions: The combination of WBC count and D-dimer levels at admission was independently associated with in-hospital outcomes of AIS patients. The addition of WBC to D-dimer levels had a tendency to improve the predictive power for in-hospital mortality and pneumonia. [ABSTRACT FROM AUTHOR]

Moso bamboo was firstly treated in a vacuum chamber at 150°C, 170°C, 190°C, and 210°C for 1, 2, and 3 h, respectively. Nano-TiO2 gel were then coated on the surface of thermally treated (TM) bamboo. Finally, specimens were radiated by an accelerated aging chamber of xenon lamp for 144 h. Chroma Meter, Scanning electron microscopy and Energy-dispersive spectroscopy (SEM-EDS) were applied to investigate the effect of nano-TiO2 coating on the surface color stability of TM bamboo. Results revealed that TM imposed a significant effect on the surface color of bamboo, e.g. when treatment temperature and duration increased, bamboo surface became darker. The color parameters of TM bamboo coated with nano-TiO2 gel after aging were close to the bamboo before aging, indicating that the photo-discoloration resistance of the TM bamboo has been improved. The nano-TiO2 gel with a concentration of 10% shows a better effect than that of 5%. After aging for 144 h, the ΔE of TM bamboo (190°C/2 h) coated by nano-TiO2 gel with a concentration of 10% was 2.90, which decreases by 25% compared with that of uncoated bamboo. Furthermore, the nano-TiO2 coating had no obvious aging failure after 144 h aging, which avoided the leaching of TiO2 particles during the long-term service. [ABSTRACT FROM AUTHOR]