Characterizing atom clouds using a charge-coupled device for atom-interferometry-based G measurements.

Precise information of positions and sizes of atom clouds is required for atom-interferometry-based G measurements. In this work, characterizing atom clouds using a charge-coupled device (CCD) is presented. The parameters of atom clouds are extracted from fluorescence images captured by the CCD. For characterization, in-situ calibration of the magnification of the imaging system is implemented using the free-fall distance of atom clouds as the dimension reference. Moreover, influence of the probe beam on measuring the positions of atom clouds is investigated, and a differential measurement by reversing the direction of the probe beam is proposed to suppress the influence. Finally, precision at sub-mm level for characterizing atom clouds is achieved.

Effect of the BOPPPS model combined with case-based learning versus lecture-based learning on ophthalmology education for five-year paediatric undergraduates in Southwest China.

BACKGROUND: To investigate the effect of the bridge-in, objective, preassessment, participatory learning, post assessment, and summary (BOPPPS) model combined with case-based learning (CBL) on ophthalmology teaching for five-year paediatric undergraduates. METHODS: The effects of the BOPPPS model combined with CBL (BOPPPS-CBL) and traditional lecture-based learning (LBL) on ophthalmology teaching were compared among students in a five-year programme. The questionnaire surveys of the students were collected and statistically analysed after the class. The final examination scores, including on elementary knowledge and case analysis, in the two groups were analysed. RESULTS: There were no statistically significant differences between the teachers and students in the baseline data. More students agreed that the BOPPPS-CBL model helped develop their problem-solving skills, analytical skills and motivation for learning better than the LBL model. There was no significant difference in learning pressure between the two groups. The final examination scores of the BOPPPS-CBL group were significantly higher than those of the LBL group. The overall course satisfaction of the BOPPPS-CBL group was obviously higher than that of the LBL group. CONCLUSIONS: The BOPPPS-CBL model is an effective ophthalmology teaching method for five-year paediatric undergraduates.

Severe ophthalmia neonatorum in Southwest China: a 5-year review of demographics, microbiological results, and risk factors.

PURPOSE: To evaluate the microbiological characteristics and risk factors of severe ophthalmia neonatorum (ON) in Southwest China. METHODS: In this retrospective review, data on demography, microbiological results, and risk factors were analyzed. Data were obtained from medical records of patients with severe ON treated at Children's Hospital of Chongqing Medical University from January 2015 to December 2019. To understand the risk factors for severe ON, maternal and neonatal factors were compared between the severe and non-severe ON groups. RESULTS: A total of 1397 neonates with ON were included, of whom 12% (n = 172) had severe ON, and 88% (n = 1225) had non-severe ON. Microbial detection and drug susceptibility tests were performed on 169 patients with severe ON. Culture results were positive for 76 patients, with gram-positive bacteria in 71.1% (n = 54), gram-negative bacteria in 25.0% (n = 19), and multiple microorganisms in 3.9% (n = 3) neonates. The most commonly detected organisms were Staphylococcus aureus (29%) and Staph. epidermis (27%), followed by Escherichia coli (8%). Neisseria gonorrhea (8%), Moraxella catarrhal (5%), Streptococcus pneumoniae (4%), Haemophilus influenza (4%), and Chlamydia trachomatis (1%). The main risk factors for severe ON were obstruction of the nasolacrimal duct (χ2 = 10.794, P = 0.001), meconium aspiration syndrome (χ2 = 6.252, P = 0.012), and cesarian section (χ2 = 5.118, P = 0.024). Neonatal ocular prophylaxis was a protective factor for severe conjunctivitis (χ2 = 6.905, P = 0.009). CONCLUSIONS: Staphylococcus is the most common pathogen of severe ON. Nasolacrimal duct obstruction (NLDO) is a risk factor for ON.

Thygeson's superficial punctate keratitis (TSPK): a paediatric case report and review of the literature.

BACKGROUND: Thygeson's superficial punctate keratitis (TSPK) is reportedly a rare disease with an insidious onset, numerous remissions and exacerbations, and a long duration. The corneal lesions are elevated, whitish-grey in colour, and granular in the intraepithelium. A few reported cases of TSPK exist, and paediatric experience is limited. Due to the unknown aetiology and controversial treatment strategies for TSPK, we performed a literature review to summarize the criteria for the diagnosis, treatment and prognosis of TSPK to provide a basis for the treatment of TSPK in paediatric patients. CASE PRESENTATION: The clinical course of a boy with TSPK who repeatedly presented with episodes of tearing, photophobia and foreign body sensation in both eyes is described. Irritation was uncontrollable with antiviral and antibiotic medications, and it was managed by corticosteroids. No recurrence was reported at the 1-year follow-up after corticosteroid replacement and tapering. CONCLUSIONS: The clinical features, treatment and prognosis between adult and paediatric TSPK patients have many similarities. The diagnosis of TSPK in children is more difficult, leading to missed diagnosis. TSPK needs to be carefully differentiated from other types of keratitis, especially intraepithelial secondary and other infectious ocular surface diseases.

Influence of Vitamin A deficiency on the transcriptomic profile of rat meibomian glands.

PURPOSE: Vitamin A deficiency (VAD) is associated with chalazion in young children. However, the underlying molecular mechanism remains unclear. In the present study, transcriptome data from rat meibomian glands (MGs) were analyzed to reveal specific molecular responses to VAD. METHODS: Total RNA was extracted and purified for library preparation and transcriptome sequencing. Differentially expressed genes (DEGs) between vitamin A normal (VAN) and VAD rats were analyzed using DESeq software. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of DEGs were performed using the GO seq R package and KOBAS software. Real-time quantitative reverse transcription polymerase chain reaction was used to validate the RNA sequencing results. RESULTS: The number of DEGs in the VAD group compared to the VAN group was 3129 (1531 upregulated and 1598 downregulated) in the rat MGs. VAD upregulated a large number of lipid metabolism-related genes. GO analysis showed that the most enriched and meaningful terms were related to lipid metabolism (e.g., "oxidation-reduction process, GO: 0,055,114," "lipid metabolic process, GO: 000,662"). KEGG pathway analysis showed that most of the enriched signaling pathways were involved in lipid metabolism, including the PPAR signaling pathway associated with retinoic acid (RA)-mediated nuclear receptors. CONCLUSION: These findings demonstrate that VAD regulates the expression of numerous genes in the rat MG and that many of these genes are involved in lipid metabolic pathways.

Incidence of retinopathy of prematurity in southwestern China and analysis of risk factors.

BACKGROUND: The aim of this study was to screen for retinopathy of prematurity (ROP) in southwestern China and understand the prevalence and risk factors of ROP, which may provide evidence useful in the prevention and treatment of ROP. MATERIAL/METHODS: 1864 preterm infants (gestational age of <37 weeks and birth weight of ≤2500 g) underwent ROP screening from January 2009 to November 2012 in Southwest China. The medical information of infants during perinatal period was reviewed, and risk factors of ROP were determined. A total of 1614 infants were recruited for final analysis. RESULTS: Incidence of ROP was 12.8%. The first, second, third, and fourth stage of ROP was found in 64.6%, 29.6%, 3.4%, and 0.5% of infants, respectively. No fifth stage of ROP was observed. In addition, 7.7% of infants required surgical intervention. In our Department of Neonatology, the incidence of ROP was 20.0%, which was significantly higher than in non-hospitalized patients (9.9%). The incidence of ROP remained unchanged over the years. Independent risk factors of ROP included low birth weight (p=0.049), low gestational age (p=0.008), days of oxygen supplementation (p=0.008), and myocardial injury after birth (p=0.001). CONCLUSIONS: The prevalence of ROP in preterm infants is relatively high in Southwest China, and low birth weight, low gestational age, days of oxygen supplementation, and myocardial injury after birth are independent risk factors for ROP.

Flipped Classroom Based on Outcomes-Based Education Improves Student Engagement and Clinical Analysis Competence in Undergraduates Ophthalmology Clerkship.

Objective: To investigate the effectiveness of flipped classrooms (FC) based on outcomes-based education (OBE) on clinical ophthalmology clerkships. Methods: Ninety-nine undergraduates were non-randomly assigned to the FC based on the OBE (FC-OBE) group or traditional lecture (TL) group in the ophthalmology clerkship. Pre- and post-tests were performed to assess student learning outcomes. Anonymous questionnaires were collected to compare students' attitudes and classroom engagements between the two groups. Results: More participants agreed FC-OBE was helpful in developing teamwork ability and knowing the work standard. Teaching staff in the FC-OBE classroom received higher evaluations. More participants in the FC-OBE group had higher classroom engagement in skills and emotions than in the TL group. The post-class test scores, mainly case analysis scores were higher in the FC-OBE group than in the TL group. Conclusion: FC-OBE classroom improves student engagement and clinical analysis competence in undergraduate ophthalmology clerkship.

Measuring the effective height for atom gravimeters by applying a frequency jump to Raman lasers.

As the existence of the gravity gradient, the output of gravimeters is actually the gravitational acceleration at the reference instrumental height. Precise knowledge of the reference height is indispensable in the utilization of gravity measurements, especially for absolute gravimeters. Here, we present an interferometric method to measure the distance between the atomic cloud and a reflecting mirror directly, which consequently determines the reference height of our atom gravimeter. This interferometric method is based on a frequency jump of Raman lasers applied at the π pulse of the atom interferometer, which induces an additional phase shift proportional to the interested distance. An uncertainty of 2 mm is achieved here for the distance measurement, and the effect of the gravity gradient on absolute gravity measurements can thus be constrained within 1 µGal. This work provides a concrete-object-based measurement of the reference height for atom gravimeters.

Effects of microRNA-29a on retinopathy of prematurity by targeting AGT in a mouse model.

BACKGROUND: This study aimed to explore the effects of microRNA-29a (miR-29a) on retinopathy of prematurity (ROP) by targeting angiotensinogen (AGT) expression in a mouse model. METHODS: Ninety-six C57BL/6J mice were selected and divided into the normal control group (n = 12) and the oxygen-induced retinopathy (OIR) group (n = 84). All the mice in the OIR group were assigned to the following seven groups (12 mice in each group): the blank, miR-29a mimics, miR-29a inhibitors, empty plasmid, miR-29a mimics + si-AGT, miR-29a inhibitors + si-AGT and si-AGT groups. ADPase histochemical staining was conducted to detect the morphology of retinal neovascularization. H&E staining was performed to quantify retinal neovascularization. The qRT-PCR assay was applied to detect the expression levels of miR-29a and the AGT mRNA. Western blotting was used to detect the protein expressions of AGT, vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), angiotensin (ANG) and angiotensin II (AngII). RESULTS: Compared with the normal control group, miR-29a expression decreased, while the AGT mRNA expression and the protein expression levels of AGT, VEGF, HGF, ANG and AngII increased, and retinal vascular density and neovascularization also increased in the OIR group. In the OIR group, compared with the blank, empty plasmid, miR-29a inhibitors and miR-29a inhibitors + si-AGT groups, miR-29a expression increased, while the AGT mRNA expression and protein expression levels of AGT, VEGF, HGF, ANG and AngII decreased, and retinal vascular density and neovascularization also decreased in the miR-29a mimics, miR-29a mimics + si-AGT and si-AGT groups. CONCLUSION: MiR-29a could inhibit retinal neovascularization to prevent the development and progression of ROP by down-regulating AGT.

Refractive status and optical components of premature babies with or without retinopathy of prematurity at 3-4 years old.

PURPOSE: To investigate the refractive status and optical components of premature babies with or without retinopathy of prematurity (ROP) at 3-4 years old, and to explore the influence of prematurity and ROP on the refractive status and optical components. METHODS: Premature babies receiving fundus examination were recruited into ROP group and non-ROP group, with age-matched full-term babies as controls. RESULTS: The incidence of myopia was the highest in ROP (3/59, 5.08%). The incidence of astigmatism was significantly different between ROP (37.29%, 22/59) and controls (17.86%, 15/84). The corneal refractive power in ROP and non-ROP was more potent compared with controls (P<0.05); corneal curvature was steeper (P<0.05); lens thickness was thinner (P<0.05); ocular axial length was shorter P<0.05). The gestational age was negatively related to corneal astigmatism and astigmatism, positively associated with vitreous thickness and axial length. The birth-weight was negatively associated with corneal astigmatism, astigmatism and corneal refractive power, positively related to corneal radius of curvature, vitreous thickness and ocular axial length. CONCLUSION: Premature babies with or without ROP are susceptible to myopia and astigmatism. ROP, prematurity and low birth-weight synergistically influence the development of refractive status and optical components, of which the prematurity and low birth-weight are more important.