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CHF3/Ar plasma was used to etch LiTaO3 crystal by inductively coupled plasma technology. The etched crystals under different process parameters were analyzed by surface profilometer and characterized by atomic force microscopy and scanning electron microscope. It was shown that ICP power, RIE power, and total gas flow rate had similar effects on etching rate and selectivity, while Ar/(Ar + CHF3) gas ratio had opposite effects on etching rate and selectivity, with better etching rate and selectivity at the ratio of 0.2. Our work gives a fundamental instruction for the fabrication of LiTaO3 based devices. [ABSTRACT FROM AUTHOR]

In PON-based mobile fronthauls, direct inter-ONU communications without passing end-user traffic to the OLT offer a promising solution for fulfilling the stringent latency and bandwidth requirements of 5G and beyond networks. In this paper, with slight modifications to the PON remote node, a concurrent inter-ONU and upstream communication technique is proposed and experimentally demonstrated in 101.6Gbit/s multipoint-to-point hybrid SSB OFDM digital filter multiple access (DFMA) IMDD PONs over 25km SSMFs. Multiple gapless inter-ONU and upstream SSB signals are aggregated by digital orthogonal filtering in each ONU transmitter. A single FFT operation is applied for demultiplex and demodulation in the OLT/ONU receivers. The results show that for both the inter-ONU and upstream transmissions, the optimum length of digital filters is 32, based on which the power penalties due to the fiber transmission and ONU channel interference are <1dB and <2dB, respectively. For the inter-ONU communications, adaptive RF spectral assignments can effectively mitigate the Rayleigh and Brillouin backscattering effects and the upstream channel fading effect, thus giving rise to >30% improvements in aggregated signal transmission capacity. In addition, detailed experimental investigations are also undertaken of the trade-off between differential ONU optical launch power dynamic range and aggregated signal transmission capacity. An approximately 1dB increase in ONU launch power dynamic range is achievable by reducing the aggregated signal transmission capacity by 5Gbit/s. [ABSTRACT FROM AUTHOR]

CHF3/Ar plasma was used to etch LiTaO3 crystal by inductively coupled plasmas technique. X-ray photoelectron spectroscopy was performed to investigate the etching mechanism. It was found that chemical reactions had occurred between the F plasma and the Li and Ta metal species, forming the corresponding fluorides. Some fluorides are nonvolatile, and remained on the surface during the etching period. In order to get higher etching rate, it is important to remove these metal fluorides. The combination of chemical reaction and sputtered etching was performed and could effectively remove the remaining residues. [ABSTRACT FROM AUTHOR]

Al doped p-type 6H silicon carbide was irradiated by low energy electrons to create primary defects. Two deep levels at EV+0.36 eV and EV+0.81 eV were created by this irradiation. Isochronal annealing study was carried out on the electron irradiated sample to investigate the annealing out of the two primary defects and the creation of thermal annealing-induced secondary defects. Four more deep hole traps (0.45, 0.56, 0.74, and 0.71 eV above the valence band) were formed during the whole annealing process up to a temperature of 1600 °C. All the electron irradiated deep level defects were annealed out after the 1600 °C annealing. [ABSTRACT FROM AUTHOR]

Low-temperature photoluminescence spectroscopy has revealed a series of features labeled S1, S2, S3 in n-type 6H-SiC after neutron and electron irradiation. Thermal annealing studies showed that the defects S1, S2, S3 disappeared at 500 °C. However, the well-known D1 center was only detected for annealing temperatures over 700 °C. This experimental observation not only indicated that the defects S1, S2, S3 were a set of primary defects and the D1 center was a kind of secondary defect, but also showed that the D1 center and the E1, E2 observed using deep level transient spectroscopy might not be the same type of defects arising from the same physical origin. [ABSTRACT FROM AUTHOR]

Population growth and climate change pose challenges to the sustainability of poultry farming. The emphasis on high-yield traits in commercialized breeds has led to a decline in their adaptability. Chicken varieties adapted to the local environment, possessing traits that facilitate adaptation to climate change, such as disease resistance and tolerance to extreme weather conditions, can improve hybridization outcomes. In this study, we conducted an analysis of the population structure and genetic diversity of 110 chickens representing indigenous breeds from southern China and two different commercial breeds. Further, we performed comparative population genomics, utilizing nucleotide diversity and fixation statistics, to characterize genomic features of natural selection and to identify unique genetic traits and potential selection markers developed by indigenous breeds after adapting to the local environment. Results based on genetic diversity and population structure analyses showed that indigenous varieties exhibited high levels of genetic diversity. Commercial breeds that have been indigenously bred demonstrated higher levels of genetic diversity than those that have not, and breeds with different selection practices displayed significant differences in genetic structure. Additionally, we further searched for potential genomic regions in native chicken ecotypes, uncovering several candidate genes related to ecological adaptations affecting local breeds, such as IKBKB, S1PR1, TSHR, IL1RAPL1 and AMY2A, which are involved in disease resistance, heat tolerance, immune regulation and behavioral traits. This work provides important insights into the genomic characterization of ecotypes of native chicken in southern China. The identification of candidate genes associated with traits such as disease resistance, heat tolerance, immunomodulation, and behavioral traits is a significant outcome. These candidate genes may contribute to the understanding of the molecular basis of the adaptation of the southern native chicken to the local environment. It is recommended that these genes be integrated into chicken breeding programs to enhance sustainable agriculture and promote effective conservation and utilization strategies., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Heat stress is a major problem that constrains pig productivity. Understanding and identifying adaptation to heat stress has been the focus of recent studies, and the identification of genome-wide selection signatures can provide insights into the mechanisms of environmental adaptation. Here, we generated whole-genome re-sequencing data from six Chinese indigenous pig populations to identify genomic regions with selection signatures related to heat tolerance using multiple methods: three methods for intra-population analyses (Integrated Haplotype Score, Runs of Homozygosity and Nucleotide diversity Analysis) and three methods for inter-population analyses (Fixation index (F ST ), Cross-population Composite Likelihood Ratio and Cross-population Extended Haplotype Homozygosity). In total, 1 966 796 single nucleotide polymorphisms were identified in this study. Genetic structure analyses and F ST indicated differentiation among these breeds. Based on information on the location environment, the six breeds were divided into heat and cold groups. By combining two or more approaches for selection signatures, outlier signals in overlapping regions were identified as candidate selection regions. A total of 163 candidate genes were identified, of which, 29 were associated with heat stress injury and anti-inflammatory effects. These candidate genes were further associated with 78 Gene Ontology functional terms and 30 Kyoto Encyclopedia of Genes and Genomes pathways in enrichment analysis (P < 0.05). Some of these have clear relevance to heat resistance, such as the AMPK signalling pathway and the mTOR signalling pathway. The results improve our understanding of the selection mechanisms responsible for heat resistance in pigs and provide new insights of introgression in heat adaptation., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Objective: To investigate the middle ear function of the patients with cleft palate pre and post palatoplasty. Methods: 76 patients with cleft palate were investigated by clinical history and audiology examinations including electric otoscopy,tympanometry and click-ABR threshold. Results: The risk for middle ear function decreased with advancing age in the first 5 years. It was noticed that the otologic outcomes was related to the CP type. During long time follow-up, the frequency with the middle ear function disorder was always high within the CP patients but the proportion of the patients received tympanostomy tubes was low relatively. The prevalence of middle ear dysfunction did not differ with the time of cleft palate repair. Conclusion: The patients with cleft palate have middle ear function dysfunction in a long period of time,therefore a standard long-time follow-up system is necessary.

Background: The aim of this study was to describe the incidence, time of onset, clinical characteristics, and outcomes of Pseudomonas aeruginosa infection after liver transplantation (LT) and to investigate the drug resistance of P aeruginosa to frequently used antibiotics to provide evidence for clinical prevention and therapy., Methods: Patients undergoing LT from January 1, 2003, through June 30, 2015, were considered. We determined the site of infection and the drug susceptibility of P aeruginosa isolates and collected these patients' data to confirm post-LT clinical and laboratory characteristics., Results: Of the 303 patients who underwent cadaveric LT, 15 (5.0%) developed 20 episodes of P aeruginosa infection. All episodes of P aeruginosa infection were early-onset, with the bloodstream being the most common source of infection. The majority (86.7%) of these recipients were in intensive care unit stay, and 7 (46.7%) patients had a body temperature of ≥38°C at the onset of infection and an inappropriate antibiotic therapy. In 14 (93.3%) patients, P aeruginosa infection was nosocomial infection. Platelet numbers of <50 × 10(9)/L and lymphocyte count of <300/mm(3) developed in 33.3% and 46.7% of patients, respectively. Seven (46.7%) deaths were attributable to P aeruginosa infection. Of these 20 P aeruginosa isolates, 10 (50%) each were carbapenem-resistant and multidrug-resistant. P aeruginosa was relatively susceptible to amikacin, levofloxacin, or cefoperazone-sulbactam (resistance rate, 30%)., Conclusions: The bloodstream was the most common site of infection; a high body temperature, nosocomial origin, decreased platelet and lymphocyte count occurring in the early period after LT, high antibiotic resistance rate, and high morbidity and mortality rates were the main characteristics of P aeruginosa infection., (Copyright © 2016 Elsevier Inc. All rights reserved.)