[Study on flow field characteristics of dust airflow in vibrating screen and optimization of dust removal system].

In order to solve the problem of dust hazard of vibrating screen machine and difficult treatment in catalyst production process, computational fluid dynamics software Fluent was used to carry out numerical simulation calculation of the local exhaust dust removal system for the main dust dispersing points of the vibrating screen machine, including fine/coarse particles outlet and product outlet blowing and cleaning the dust points. The optimal design scheme and key technical parameters of local ventilation and dust removal system of vibrating screen machine were proposed. The results showed that the dust diffusion could be prevented by setting up an upper suction hood without air blowing, but the exhaust air volume needed to be calculated accurately. On the premise of purge, it is necessary to control the air volume to form a wind speed band of 8 m/s with a height of 15 cm at the feed port, so as to effectively remove the dust on the surface of solid particles of catalyst products and ensure that the catalyst products will not be blown away when falling into the feed barrel. The simulated design was applied to the vibrating sieve powder machine of a catalyst company, and the maximum dust concentration in the workplace was reduced from 45.80 mg/m(3) to 5.46mg/m(3), which effectively improved the working environment in the workplace.

Half-year follow-up of patients recovering from severe COVID-19: Analysis of symptoms and their risk factors.

OBJECTIVES: To understand the sequelae of COVID-19. METHODS: We followed up 1174 patients with severe coronavirus disease 2019 (COVID-19)who were recovered and discharged for 6 months. RESULTS: There were 175 cases with clear IgG results 6 months after discharge, of which 82 (46.9%) were IgG (+) and 16 (9.1%) were IgG (dim+). Four hundred and forty-one participants (55.4%) had some kind of sequelae. The most common symptoms were fatigue (25.3%), sleep disorder (23.2%) and shortness of breath (20.4%). In those who had sequelae, 262 (59.4%) had more than one symptom. Critical cases were more likely to have cough (20.5% vs 11.6%, p = 0.023) and hypomnesis (15.1% vs 8.0%, p = 0.041) than severe cases. Furthermore, univariate and multivariate logistic regression analyses revealed that women are more likely to have multiple symptoms (p = 0.002), fatigue (p = 0.009) and sleep disorder (p = 0.008), whereas critical illness was found as independent risk factor for hypomnesis (p = 0.045). CONCLUSION: Our study demonstrated the duration of antibody and sequelae of COVID-19 and compared the differences amongst different populations.

Follicle Stimulating Hormone Inhibits the Expression of p53 Up-Regulated Modulator of Apoptosis Induced by Reactive Oxygen Species Through PI3K/Akt in Mouse Granulosa Cells.

In mammalian ovaries, follicular atresia occurs periodically and destroys almost all the follicles in the ovary. Follicle-stimulating hormone (FSH) acts as the primary survival factor during follicular atresia by preventing apoptosis in granulosa cells (GCs). Many studies have demonstrated that oxidative stress-induced apoptosis is a main cause of follicular atresia. Reactive oxygen species (ROS)-induced GCs apoptosis is regulated by a variety of signaling pathways involving numerous genes and transcription factors. Therefore, we examined whether FSH inhibits the expression of p53 up-regulated modulator of apoptosis (PUMA) induced by reactive oxygen species (ROS) through phosphoinositide 3-kinase (PI3K) / protein kinase B (AKT) in mouse GCs. In vivo study: thirty-two-mice were randomly assigned to four groups and given FSH. We found that FSH can inhibit the 3-nitropropionic acid (3-NP) induced apoptosis and PUMA expression in mRNA level. Moreover, In vitro experiment, we found that FSH can inhibit the H(2)O(2)-induced apoptosis and PUMA expression in mRNA level. Additionally, we also found that PI3K/AKT inhibitor LY294002 abolished the downregulation of PUMA mRNA by FSH in vitro, In conclusion, FSH inhibit the expression of PUMA induced by ROS through PI3K/AKT pathway in vivo and vitro.

[Association between PON2 gene polymorphisms and susceptibility to noise-induced hearing loss].

Objective: To investigate the relationship between SNP and noise-induced hearing loss (NIHL) susceptibility in occupational noise exposure population in China. Methods: From 6297 for a certain steel works in contact with noise, contact length of 3 years or more and workplace noise exposure intensity of 80 dB (A) , ears or high frequency (3 000, 4 000, 6 000 Hz) average of hearing acuity 40 dB (HL) , or high frequency loss in both ears, on the basis of single whisper frequency (500, 1, 000, 2 000 Hz) average threshold of 26 dB (HL) or object as case group. A case-control study was designed with 1:1 matching. Subjects with the same gender, the same type of work, age ±5 years old, and working age ±2 years after noise exposure were selected as the control group. Subjects with any whisper frequency (500, 1, 000, 2, 000 Hz) whose hearing threshold in any frequency band was ≤25 dB (A) and whose average high-frequency hearing threshold in pure tone hearing test was <35 dB (A) were selected as the control group. Four sites of PON2 gene were genotyped by medium-and high-throughput SNP genotyping. Univariate logistic regression was used to analyze the relationship between single SNP polymorphism and NIHL. Results: A total of 286 case-control pairs were included. Smoking was statistically significant difference between cases and controls (P<0.001) . Conclusion: No statistical difference has been found between single SNP polymorphism and NIHL. At the level of greater than 92 dB of high noise exposure, rs7785846 (CT+TT) genotype is a risk factor for occupational noise deafness, and its OR is 2.74 (95%CI: 1.09-6.89) compared with wild homozygous type (CC) . Conclusion. The rs7785846 (CT+TT) genotype carriers of PON2 gene are more susceptible to hearing impairment when exposed to high noise intensity.

[Biomechanical study of bridge-link type combined internal fixation system with mixed-rod in the treatment of long segmental comminuted fracture of femoral shaft].

Objective: To observe the biomechanical characteristics of bridge-link type combined internal fixation system (BCFS) with mixed-rod in the treatment of long segmental comminuted fracture of femoral shaft. Methods: A total of 16 models of long comminuted segment fracture of femoral shaft with mixed-rod and double-rod were made (8 each structure), and divided into the mixed-rod group and the double-rod group. The axial compression experiment and the radial torsion experiment were carried out on each of the mixed rod group and the double rod group. Four models were randomly selected from the two groups for axial compression experiment and radial torsion experiment, respectively. The changes of axial compression yield load and displacement, and also radial torsional yield load and angle were observed in two groups. At the same time, the maximum load was recorded when the curve had a break point or in a horizontal state, and then calculated the yield load. The data of normal distribution were compared with one-sample t test. Results: When the two groups were compressed axially at the same speed, as the axial compression yield load increased gradually, the longitudinal compression displacement of the mixed-rod group was obviously smaller than that in the double-rod group; and the maximum axial compression yield load of the mixed-rod group was greater than that in the double-rod group ((7 517±4)N vs (2 290±4) N, t=1 848.071, P=0.000). When the two groups were twisted radially at the same speed,as radial torsional yield load increased gradually, the radial torsion angle of the mixed-rod group was smaller than that in the double-rod group; and the maximum radial torsional yield load of the mixed-rod group was greater than that in the double-rod group ((61.3±2.0) Nm vs (24.4±2.2)Nm, t=25.201, P=0.000). Conclusions: For the long segment comminuted fracture of femoral shaft, the mixed-rod of BCFS can fix fracture more strongly than double-rod in longitudinal direction and maintain the stability of fracture end. The transverse torsion resistance is better than that of the double-rod, and the fatigue resistance is strong.

Cellular and molecular mechanisms of low dose prolactin potentiation of testicular development in cockerels.

The aim of this study was to determine the cellular and molecular mechanisms of prolactin (PRL) in testicular development of prepubertal cockerels. In an in vivo animal experiment, active immunization against PRL severely depressed prepubertal testicular development by significantly reducing testicular weights at both 122 and 164 d of age. The number of elongated spermatids in the seminiferous tubules was also significantly decreased by immunization with 199-residue chicken PRL (cPRL) at age 122 d. Inhibition of testicular development by cPRL immunization was associated with decreases in LH receptor (LHR), FSH receptor (FSHR), Stat5b, P450scc, steroidogenic acute regulatory (StAR) protein, and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) mRNA expression levels in testicular tissue. In in vitro experiments, testosterone production by cultured Leydig cells isolated from prepubertal cockerel testes was dose-dependently enhanced by treatment with bioactive recombinant PRL, but a lesser response was seen with high concentrations of PRL. The distinct changes in testosterone production in response to high and low concentrations of added PRL were paralleled by similar patterns of change in the mRNA levels of Stat5b, LHR, P450scc, StAR, 3ß-HSD, and CYP17A1 in cultured Leydig cells, as well as protein amounts of phosphorylated Jak2 and Stat5a/b. In conclusion, low to medium doses of PRL potentiate testis development in prepubertal cockerels by enhancing testosterone secretion from Leydig cells via activation of PRLR/Stat5b signal transduction, which upregulates mRNA expression of LHR and testosterone synthesizing enzymes. However, this positive regulation was weaker in response to a high dose of PRL, which reduced PRLR/Stat5b signal transduction and the expression of genes involved in LH signaling and testosterone synthesis.

Endocrine and molecular regulation mechanisms of the reproductive system of Hungarian White geese investigated under two artificial photoperiodic programs.

Hungarian White geese are regarded as good producers of meat, eggs, and feathers, but specific lighting schedules are required to improve their egg-laying performance. This study reveals the neuroendocrine regulatory mechanisms that govern the reproductive activities and egg-laying performances of Hungarian White geese. The results indicated that increasing the daily photoperiod from a short 8 h period to either 11 h or 14 h initiated reproduction. Egg-laying rates increased faster in the 14 h group, peaking (48.2%) on day 33 as compared to the peak (52.67%) reached on day 53 in the 11 h group. Changes to the plasma estradiol and progesterone concentrations produced similar patterns in the two groups. In the hypothalamus, OPN5, Dio2, c-Fos, and GnRH-I expression levels showed similar sequential increases and decreases. Changes in GnIH and VIP expression levels were the opposite to those of GnRH-I, but the levels peaked earlier under the 14 h photoperiod conditions. Pituitary LH beta and FSH beta expression levels increased at slower rates but remained significantly higher in the 11 h group than in the 14 h group. However, pituitary PRL expression increased considerably earlier and was higher in 14 h geese than in 11 h geese, which was opposite to the observed egg-laying rate patterns. An increase from a short to a relatively long photoperiod (11 h) regulated the neuroendocrine system and led to reproductive activities being sustained for a longer period, which resulted in high egg-laying performances.

Development of polymorphic microsatellite loci in Odontobutis obscura using Illumina paired-end sequencing and the test of cross-species amplification.

Odontobutis obscura is a bottom-dwelling freshwater fish native to East Asia. Its range encompasses southwest China, western Japan, and Geoje Island in South Korea. Despite its widespread range in China and Japan, only a small and spatially isolated population is found in South Korea. We developed a total of 23 novel and polymorphic microsatellite loci of O. obscura using Illumina paired-end shotgun sequencing and characterized them using 80 Japanese and Korean samples. An extensive genetic polymorphism was detected at these 23 loci, with the observed number of alleles at a locus ranging from 2 to 15 and expected and observed heterozygosities ranging from 0 to 0.656 and 0 to 0.547, respectively. Korean O. obscura exhibited a much lower level of genetic variability than the Japanese population did, probably as a result of long-term isolation combined with historical bottlenecks. The Japanese and Korean populations showed a high level of genetic differentiation with FST = 0.700 and RST = 0.913. Many of our primer sets were successfully transferable to congeneric O. interrupta and O. platycephala, which exhibited even greater polymorphism than Korean O. obscura. In conclusion, our study showed that these 23 microsatellite markers are useful for understanding the conservation biology and population genetic structure of O. obscura and other congeneric species.

[Current status of hearing loss and related influencing factors in workers with noise exposure in refining and chemical industry].

Objective: To investigate the current status of hearing loss and related influencing factors in workers with noise exposure in refining and chemical industry. Methods: From August 2015 to March 2016, the investigation method of collecting the data of past occupational health examinations and measuring noise in working environment was used to enroll 8 672 male workers. Results: Of all workers, 11.6% were diagnosed with hearing loss. There were significant differences in the distribution of hearing impairment among workers exposed to noise at different ages, device types and types of work (χ(2)=17.80, 77.80 and 30.53, all P<0.05) . The level of noise exposure≥85 dB (A) (OR=5.79, 95%CI 3.70-8.81) , working years with noise exposure (OR=1.57, 95%CI 1.05-2.43) , and 25 years (OR=3.29, 95%CI 2.08-5.71) were risk factors for hearing loss in workers with noise exposure in refining and chemical industry. Conclusion: The level of noise exposure and working years with noise exposure are main influencing factors for hearing loss in workers with noise exposure in refining and chemical industry.

[Association between CDH23 gene polymorphisms and susceptibility to noise-induced hearing loss in the Chinese population: a meta-analysis].

Objective: To investigate the association between cadherin-23 (CDH23) gene polymorphisms and susceptibility to noise-induced hearing loss (NIHL) in the Chinese population through a meta-analysis. Methods: In June 2016, CNKI, VIP, Wanfang Data, and PubMed were searched for studies on the association between CDH23 gene polymorphisms and susceptibility to NIHL in the Chinese population. The articles were screened according to inclusion and exclusion criteria and related data were extracted. RevMan 5.3 was used for the meta-analysis. Results: A total of three Chinese articles were included. For CDH23-rs1227049, the risk of NIHL in people with C allele was 0.82 times (95%CI 0.39-1.73) that in people with G allele, the risk of NIHL in people with CG+CC genotype in the dominant model was 0.70 times (95%CI 0.34-1.43) that in people with GG genotype, the risk of NIHL in people with CC genotype in the recessive model was 1.23 times (95%CI 0.28-5.43) that in people with CG+GG genotype, and the risk of NIHL in people with CC genotype in the additive model was 1.05 times (95%CI 0.20-5.44) that in people with GG genotype (all P>0.05) . For CDH23-rs1227051, the risk of NIHL in people with T allele was 0.98 times (95%CI 0.71-1.37) that in people with C allele, and the risk of NIHL in people with CT+CC genotype in the dominant model was 1.09 times (95%CI 0.75-1.57) that in patients with TT genotype (both P>0.05) . Conclusion: There is still no enough evidence for the determination of CDH23-rs1227049 and CDH23-rs1227051 to be the susceptibility gene loci of NIHL.

Development of novel microsatellite markers for conservation genetic studies of Vulpes vulpes (Canidae) by using next-generation sequencing method.

The red fox, Vulpes vulpes (Canidae), is the most widely distributed terrestrial carnivore worldwide, but this species is classified as endangered in Korea. In this study, we developed 25 polymorphic microsatellite markers that included 3-13 (mean = 6.32) alleles per locus using 22 red fox individuals. The most polymorphic locus was FR(59)TG (13 alleles) and the least polymorphic loci were FR(70)TG and FR(182)AG (3 alleles each). No significant deviation from Hardy-Weinberg equilibrium (P < 0.05) was observed for the 25 markers. Observed (HO) and expected (HE) heterozygosity varied from 0.182 to 1.000 and from 0.175 to 0.929, respectively. These newly developed microsatellite markers will be useful for investigating the genetic diversity and population genetic structure of V. vulpes and will aid in developing conservation strategies for this species.

Next-generation sequencing identification and characterization of microsatellite markers in Aconitum austrokoreense Koidz., an endemic and endangered medicinal plant of Korea.

We used next-generation sequencing to develop 9 novel microsatellite markers in Aconitum austrokoreense, an endemic and endangered medicinal plant in Korea. Owing to its very limited distribution, over-harvesting for traditional medicinal purposes, and habitat loss, the natural populations are dramatically declining in Korea. All novel microsatellite markers were successfully genotyped using 64 samples from two populations (Mt. Choejeong, Gyeongsangbuk-do and Ungseokbong, Gyeongsangnam-do) of Gyeongsang Province. The number of alleles ranged from 2 to 7 per locus in each population. Observed and expected heterozygosities ranged from 0.031 to 0.938 and from 0.031 to 0.697, respectively. The novel markers will be valuable tools for assessing the genetic diversity of A. austrokoreense and for germplasm conservation of this endangered species.

Studies on enhancing embryo quantity and quality by immunization against inhibin in repeatedly superovulated Holstein heifers and the associated endocrine mechanisms.

To investigate the feasibility of improving embryo production in cattle by immunization against inhibin, both in vivo and in vitro experiments were conducted. In two experiments conducted in two autumns, 14 animals aged 14 months were immunized with a recombinant inhibin α subunit protein antigen for four times at monthly intervals, with another 14 animals of the same age served as the controls. Starting from the second immunization, all the heifers received standard superovulation treatment for three sessions, one session per month, each starting 10 days after every antigen administration. Immunization against inhibin increased number of transferable embryos (P<0.05), and high quality Grade A embryos (P<0.01) in each superovulation. Blood concentrations of FSH, estradiol, activin, and also ratio of activin to follistatin concentrations were greater in inhibin immunized than in control animals during the period of superovulatory FSH administration and animal estrous expression. Heifers immunized with inhibin also had greater concentrations of progesterone in the later diestrus period. In the second experiment, the inclusion of anti-inhibin antibody in oocyte IVM medium increased oocyte maturation rate and cleavage rate following IVF (P<0.05). These results demonstrated that inhibition of the adverse effects of inhibin on ovarian follicular development and oocyte maturation improved embryo yield, in both quantity and quality, following superovulation. These results also demonstrate that active immunization against inhibin, in conjunction with the conventional superovulation protocol, can constitute a new technique for consistent improvement of bovine embryo production in vivo; while passive immunization with anti-inhibin antibody can improve embryo production in vitro.

High color rending index and high-efficiency white organic light-emitting diodes based on the control of red phosphorescent dye-doped hole transport layer.

We have investigated the transport characteristics of red phosphorescent dye bis(1-(phenyl)isoquinoline) iridium (III) acetylanetonate (Ir(piq)2acac) doped 4,4',4"-tri(N-carbazolyl)triphenylamine (TCTA), and found that the increasing doping ratio was facilitated to improve the ability of hole transporting. A high color rendering index (CRI) and high-efficiency WOLED was achieved by employing Ir(piq)2acac doped TCTA film as an effective red emissive layer due to the generation of charge transfer complex (CTC) at the interface. The relative proportion in red: green: blue emission intensity can be controlled by the CTC concentration to obtain high CRI WOLEDs. The WOLED with an optimal red dye doping concentration of 5 wt% exhibits a high CRI of 89 and a power efficiency of 31.2 lm/W and 27.5 lm/W at the initial luminance and 100 cd/m², respectively. The devices show little variation of the Commission Internationale de I'Eclairage coordinates in a wide range of luminance.

Identification of RNA editing sites in cotton (Gossypium hirsutum) chloroplasts and editing events that affect secondary and three-dimensional protein structures.

RNA editing can alter individual nucleotides in primary transcripts, which can cause the amino acids encoded by edited RNA to deviate from the ones predicted from the DNA template. We investigated RNA editing sites of protein-coding genes from the chloroplast genome of cotton. Fifty-four editing sites were identified in 27 transcripts, which is the highest editing frequency found until now in angiosperms. All these editing sites were C-to-U conversion, biased toward ndh genes and U_A context. Examining published editotypes in various angiosperms, we found that RNA editing mostly converts amino acid from hydrophilic to hydrophobic and restores evolutionary conserved amino acids. Using bioinformatics to analyze the effect of editing events on protein secondary and three-dimensional structures, we found that 21 editing sites can affect protein secondary structures and seven editing sites can alter three-dimensional protein structures. These results imply that 24 editing sites in cotton chloroplast transcripts may play an important role in their protein structures and functions.

Injection of frozen-thawed porcine first polar bodies into enucleated oocytes results in fertilization and embryonic development.

The objective was to determine whether enucleated oocytes injected with frozen porcine first polar bodies (pPB1s) could be fertilized and developed into viable embryos in vitro. Metaphase II (MII) oocytes with pPB1s were frozen (vitrified) and stored for 2 mo. The pPB1s were isolated from thawed MII oocytes and injected into enucleated recipient oocytes by micromanipulation. All recipients injected with thawed pPB1s were fertilized by intracytoplasmic sperm injection (ICSI), and the resulting recombinant zygotes were incubated to assess their developmental competence in vitro. Furthermore, double-antibody immunohistochemistry was used to verify that the nucleus of the pPB1 participated in fertilization and supported embryonic development. Porcine embryos (2- to 8-cell stage) were obtained from the recombinants. The average in vitro cleavage rate of 2-, 4-, and 8-cell stage recombinant embryos was 25.3, 17.7, and 9.3% (P < 0.05), respectively. Chromosomes in the labeled pPB1 participated in the formation of the two blastomere nuclei of 2-cell stage embryos derived from recombinant oocytes. In conclusion, nuclear materials of frozen-thawed pPB1 supported oocyte fertilization and subsequent embryonic development, thereby providing a new way to use frozen PB1s for preservation and reproduction of mammals.

Polymorphism of the growth hormone gene and its association with growth traits in Boer goat bucks.

In the present study, the polymorphism of growth hormone (GH) gene was analyzed as a genetic marker candidate for growth traits in Boer goat bucks. Two single nucleotide polymorphisms (SNPs) - A781G (Ser/Gly35) and A1575G (Leu147), were identified by GH gene sequencing and PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) analysis. AA genotype resulted in a significant decrease in birth chest girth (P=0.03) and weaning weight (P=0.014) comparing to AB genotype, while CC genotype contributed to weaning height (P=0.04) greater than CD genotype. When in combination, AACD genotype was undesired for lower scores in a series of growth traits including body weight, length, height, and chest girth at birth and weaning, as well as the pre-weaning daily gain and body weight at age of 11 months. These results indicate that new molecular markers associated with caprine growth traits can be used in MAS (marker-assisted selection) in Boer goat bucks.

Prevalence of hepatitis E virus and sapovirus in post-weaning pigs and identification of their genetic diversity.

Hepatitis E virus (HEV) and sapovirus (SaV) induce acute hepatitis and gastroenteritis, respectively, in humans. As pigs have been recognized as an important reservoir for these viruses, we evaluated the infection rates of both viruses using fecal samples collected from post-weaning pigs via RT-PCR methods. In the five swine farms assessed in this study, 3 farms were found to be HEV-positive and 4 farms were SaV-positive. The overall prevalence of HEV and SaV in the pigs was 17.0 and 23.1%, respectively. Phylogenetic tree analysis revealed that the isolated swine HEVs belonged to genotype 3 and the porcine SaVs belonged to genogroup III. This study proved that both HEV and SaV are prevailing in post-weaning pigs in Korea.

Hyperlipidemia.

Coronary heart disease (CHD) is prevalent and often related to an unhealthy diet and hyperlipidemia. The diagnosis of hyperlipidemia should be carefully made, using more than one measurement in the manner described. An assessment of risks allows one to decide whom to treat. Patients with CHD should be treated aggressively but it is less clear how aggressive to be with patients without CHD. Diet and exercise recommendations are appropriate for almost all patients. For those for whom the benefit is greater than the potential risks, statins are first-line drug therapy and they appear to have beneficial effects aside from their lipid-lowering properties.