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Monolithic waveguide laser devices are required to achieve on-chip lasing. In this work, a new design of a monolithic device with embedded Ag nanoparticles (NPs) plus the Nd:YAG ridge waveguide has been proposed and implemented. By using Ag+ ion implantation, the embedded Ag NPs are synthesized on the near-surface region of the Nd:YAG crystal, resulting in the significant enhancement of the optical nonlinearity of Nd:YAG and offering saturable absorption properties of the crystal at a wide wavelength band. The subsequent processing of the O5+ ion implantation and diamond saw dicing of crystal finally leads to the fabrication of monolithic waveguide with embedded Ag NPs. Under an optical pump, the Q-switched mode-locked waveguide lasers operating at 1 μm is realized with the pulse duration of 29.5 ps and fundamental repetition rate of 10.53 GHz, owing to the modulation of Ag NPs through evanescent field interaction with waveguide modes. This work introduces a new approach in the application of monolithic ultrafast laser devices by using embedded metallic NPs.

Outer hair cells (OHCs) damage is a general phenomenon in clinical disorders such as noise-induced hearing loss and drug-induced hearing loss. In order to elucidate the mechanism underlying these disorders, OHCs – its diseased region needs to be deeply investigated. However, OHCs array on the basilar membrane which contains massive cells with different types. Therefore, to isolate OHCs from this huge population is significant for revealing its pathological and molecular changes during disease processing. In the present study, we tried to isolate OHCs from the commonly used animal model –Sprague-Dawley (SD) rats. By separating outer hair cells from SD rats with different day ages, we found that 9 days after birth was a suitable time for the separation of the OHCs. At this time, the number of OHCs isolated from rats was large, and the cell morphology was typical of cylindrical shape. OHCs isolated using this method are histologically suitable and quantitatively adequate for molecular biological and electrophysiological analyses. Keywords: Outer hair cell, Isolation technique, Morphology, Sprague–Dawley rat

Traditional separation methods for thick-walled metal tubes include turning and sawing, which suffer from wasted raw material and low efficiency. In view of this, this paper proposes a new process of using impact load to promote crack generation and tube separation. Based on the principles of radial repeated impact load, stress concentration effect and fatigue fracture, the rapid initiation and stable expansion of tube fatigue crack are promoted. In addition, the crack initiation mechanism of the tube V-notch root cracks under radial repeated load when the tube is in a restrained state. For the experimental study of the GCr15 steel tube, a multistep decline frequency time tube separation control curve with an initial frequency from 4 Hz to 31 Hz and termination frequency from 1 Hz to 8.5 Hz was designed, and the precision tube separation device is loaded by pneumatic fatigue shock to achieve tube precision separation. In addition, a tube fracture quality evaluation method is proposed. According to the test results, the stress concentration effect of V-notch can significantly reduce the average stress in the process of tube fatigue separation and accelerate the generation of microcracks. Under the continuous action of repeated impact load, the loading method of multistep decline can effectively control the rapid crack initiation and stable expansion of the GCr15 tube V-notch root crack. Moreover, the tube final fracture region has relatively small defects, which can obtain good fracture quality.

This study is to assess the influences of climate, socio-economic determinants, and spatial distance on the confirmed cases and deaths in the raise phase of COVID-19 in China. The positive confirmed cases and deaths of COVID-19 over the population size of 100,000 over every 5 consecutive days (the CCOPSPTT and DOPSPTT for short, respectively) covered from 25th January to 29th February, 2020 in five city types (i.e., small-, medium-, large-, very large- and super large-sized cities), along with the data of climate, socio-economic determinants, spatial distance of the target city to Wuhan city (DW, for short), and spatial distance between the target city and their local province capital city (DLPC, for short) were collected from the official websites of China. Then the above-mentioned influencing factors on CCOPSPTT and DOPSPTT were analyzed separately in Hubei and other provinces. The results showed that CCOPSPTT and DOPSPTT were significantly different among five city types outside Hubei province (p < 0.05), but not obviously different in Hubei province (p > 0.05). The CCOPSPTT had significant correlation with socio-economic determinants (GDP and population), DW, climate and time after the outbreak of COVID-19 outside Hubei province (p < 0.05), while was only significantly related with GDP in Hubei province (p < 0.05). The DOPSPTT showed significant correlation with socio-economic determinants, DW, time and CCOPSPTT outside Hubei province (p < 0.05), while was significantly correlated with GDP and CCOPSPTT in Hubei province (p < 0.05). Compared with other factors, socio-economic determinants have the largest relative contribution to variance of CCOPSPTT in all studied cities (> 78%). The difference of DOPSPTT among cities was mainly affected by CCOPSPTT. Our results showed that influences of city types on the confirmed cases and death differed between Hubei and other provinces. Socio-economic determinants, especially GDP, have higher impact on the change of COVID-19 transmission compared with other factors.

Porcine epidemic diarrhea virus (PEDV) is a devastating swine infectious disease. Development of high-performance methods to diagnose and evaluate viral immune status remains very important to control PEDV. Here, a recombinant S1 protein-based indirect enzyme-linked immunosorbent assay (rpS1-iELISA) was developed to monitor IgA antibody in the colostrum. Optimized cut-off value of the rpS1-iELISA was determined as 0.448. Results yielded a sensitivity of 96.87% and a specificity of 100.0%. Repeatability tests indicated that the coefficients of variation of the colostrum samples within and between runs were both less than 8%. Test results of 523 field colostrum samples showed that the rpS1-iELISA had excellent agreement with immunofluorescence assay (kappa = 0.958) and better test performance than a commercial ELISA kit. This test will aid in future diagnostics and assessment of the protective levels of mucosal immune response against PEDV by measuring IgA levels in the colostrum.

Neonatal lupus erythematosus (NLE) is a rare acquired condition caused by the transplacental passage of maternal autoantibodies. It is characterized by cutaneous, cardiac, hepatobiliary, hematological and neurological involvement. Cutaneous findings of NLE are variable, but few reports in the literature describe the presence of erosions or epidermal loss in NLE. Herein, we describe the case of an infant with NLE presenting as Stevens-Johnson syndrome (SJS), with cardiac, hematologic, hepatobiliary and neurologic abnormalities. The characteristic features by which to differentiate SJS-like NLE from infant SJS include subacute course, cardiac abnormalities, positive serology tests and direct immunofluorescence, histopathologic findings with melanin incontinence, periadnexal infiltrates, and mucin deposit. Though rare, it is important to consider lupus erythematosus as a potential cause of acute syndrome with focal epidermal necrosis or pan-epidermolysis. Keywords: Epidermolysis, Neonatal lupus erythematosus, Stevens-Johnson syndrome

Kernel color is an important trait for assessing the commercial and nutritional quality of foxtail millet. Yellow pigment content (YPC) and carotenoid components (lutein and zeaxanthin) of 270 foxtail millet accessions, including 50 landraces and 220 improved cultivars, from four different eco-regions in China were surveyed using spectrophotometry and high performance liquid chromatography methods. Results indicated that YPC had rich variance, ranging from 1.91 to 28.54 mg kg−1, with an average value of 17.80 mg kg−1. The average YPC of improved cultivars (18.31 mg kg−1) was significantly higher than that of landraces (15.51 mg kg−1). The YPC in cultivars from the Loess Plateau spring sowing region (LPSSR) was the highest (20.59 mg kg−1), followed by the North China summer sowing region (NCSSR, 18.25 mg kg−1), the northeast spring sowing region (NSSR, 17.25 mg kg−1), and the Inner Mongolia Plateau spring sowing region (IMPSSR, 13.92 mg kg−1). The variation coefficients of YPC in cultivars from NSSR, LPSSR, and IMPSSR were higher than that from NCSSR. A similar carotenoid profile was also obtained for 270 foxtail millet cultivars. Lutein and zeaxanthin accounted for approximately 55–65% of YPC in accessions. The lutein content was higher than zeaxanthin content in all cultivars. The ratio of lutein to zeaxanthin ranged from 1.51 to 6.06 with an average of 3.34. YPC was positively correlated with lutein (r=0.935, P

In this paper, we summarize our recent results of study on how to engineer the embedded metal nanoparticles in silica by ion implantation and ion irradiation technologies, including controlling the size, distribution and morphology of nanoparticles. The optical properties of the tailored nanoparticle composites are studied. Thermal annealing, electron beam irradiation, and chemical erosion are used to study the stability of these embedded nanoparticles by ex situ or in situ transmission electron microscopy observation.