Research on the phase error of a Sagnac interferometer induced by modulation of a multifunctional integrated optical modulator.

High-precision IFOG requires an optical sensitivity of up to 10-8 rads-1 for interferometers; noise and error are two of the main reasons limiting its accuracy improvement. Any potential source of the signal error is worth being studied. This article introduces work on the modulation signal error caused by the mechanical vibration energy loss of MIOC crystals. This article theoretically derives and simulates the frequency spectrum of an energy loss from the perspective of electromechanical coupling and verifies it through experiments. This article also verifies the influence of MIOC mechanical loss on the output of a Sagnac interferometer through experiments. This study is an indispensable part of the bottleneck for improving the accuracy of ultrahigh-precision closed-loop IFOG and has potential engineering application value.

[Impact of different diagnostic criteria for assessing mild micro-hepatic encephalopathy in liver cirrhosis: an analysis based on a prospective, multicenter, real-world study].

Objective: To compare the differences in the prevalence of mild micro-hepatic encephalopathy (MHE) among patients with cirrhosis by using the psychometric hepatic encephalopathy score (PHES) and the Stroop smartphone application (Encephal App) test. Methods: This prospective, multi-center, real-world study was initiated by the National Clinical Medical Research Center for Infectious Diseases and the Portal Hypertension Alliance and registered with International ClinicalTrials.gov (NCT05140837). 354 cases of cirrhosis were enrolled in 19 hospitals across the country. PHES (including digital connection tests A and B, digital symbol tests, trajectory drawing tests, and serial management tests) and the Stroop test were conducted in all of them. PHES was differentiated using standard diagnostic criteria established by the two studies in China and South Korea. The Stroop test was evaluated based on the criteria of the research and development team. The impact of different diagnostic standards or methods on the incidence of MHE in patients with cirrhosis was analyzed. Data between groups were differentiated using the t-test, Mann-Whitney U test, and χ (2) test. A kappa test was used to compare the consistency between groups. Results: After PHES, the prevalence of MHE among 354 cases of cirrhosis was 78.53% and 15.25%, respectively, based on Chinese research standards and Korean research normal value standards. However, the prevalence of MHE was 56.78% based on the Stroop test, and the differences in pairwise comparisons among the three groups were statistically significant (kappa = -0.064, P < 0.001). Stratified analysis revealed that the MHE prevalence in three groups of patients with Child-Pugh classes A, B, and C was 74.14%, 83.33%, and 88.24%, respectively, according to the normal value standards of Chinese researchers, while the MHE prevalence rates in three groups of patients with Child-Pugh classes A, B, and C were 8.29%, 23.53%, and 38.24%, respectively, according to the normal value standards of Korean researchers. Furthermore, the prevalence rates of MHE in the three groups of patients with Child-Pugh grades A, B, and C were 52.68%, 58.82%, and 73.53%, respectively, according to the Stroop test standard. However, among the results of each diagnostic standard, the prevalence of MHE showed an increasing trend with an increasing Child-Pugh grade. Further comparison demonstrated that the scores obtained by the number connection test A and the number symbol test were consistent according to the normal value standards of the two studies in China and South Korea (Z = -0.982, -1.702; P = 0.326, 0.089), while the other three sub-tests had significant differences (P < 0.001). Conclusion: The prevalence rate of MHE in the cirrhotic population is high, but the prevalence of MHE obtained by using different diagnostic criteria or methods varies greatly. Therefore, in line with the current changes in demographics and disease spectrum, it is necessary to enroll a larger sample size of a healthy population as a control. Moreover, the establishment of more reliable diagnostic scoring criteria will serve as a basis for obtaining accurate MHE incidence and formulating diagnosis and treatment strategies in cirrhotic populations.

[Comparison of air filled anterior approach of sternocleidomastoid muscle and space of sternocleidomastoid muscle for treatment of thyroid papillary carcinoma under axillary endoscope].

Objective: To evaluate the application of the anterior sternocleidomastoid muscle approach in transaxillary endoscopic thyroidectomy. Methods: The clinical data of 180 patients undergoing transaxillary endoscopic thyroidectomy for thyroid cancer in the Department of General Surgery of the Affiliated Hospital of Nantong University from March 2021 to March 2023 were retrospectively analyzed. There were 27 males and 153 females, aged (37.5±8.0)years, range: 27 to 52 years. The anterior approach of sternocleidomastoid muscle was used in 100 cases, and the interspace approach of sternocleidomastoid muscle was used in 80 cases between the two groups. The postoperative efficacy, complications and satisfaction of the two groups were compared. Results: There was no difference between the two groups in the number of lymph node dissection (using nano carbon tracer), hospital stay, and postoperative complications (transient decrease in parathyroid function, laryngeal nerve injury) (P>0.05). The anterior approach of sternocleidomastoid muscle had shorter cavity building time[(17.8±2.9)vs(20.1±3.7) min], less drainage volume the second day after operation[(18.7±5.2)vs(23.5±6.3) ml], and less discomfort in the neck (P<0.05). Conclusion: The anterior approach of sternocleidomastoid muscle under complete transaxillary endoscopy has certain advantages in the time of cavity construction, the drainage volume the second day after the operation, and the reduction of cervical discomfort after the operation. The operation is safe and reliable.

Effect of avian influenza virus subtype H9N2 on the expression of complement-associated genes in chicken erythrocytes.

1. The H9N2 subtype avian influenza virus can infect both chickens and humans. Previous studies have reported a role for erythrocytes in immunity. However, the role of H9N2 against chicken erythrocytes and the presence of complement-related genes in erythrocytes has not been studied. This research investigated the effect of H9N2 on complement-associated gene expression in chicken erythrocytes.2. The expression of complement-associated genes (C1s, C1q, C2, C3, C3ar1, C4, C4a, C5, C5ar1, C7, CD93 and CFD) was detected by reverse transcription-polymerase chain reaction (RT-PCR). Quantitative Real-Time PCR (qRT-PCR) was used to analyse the differential expression of complement-associated genes in chicken erythrocytes at 0 h, 2 h, 6 h and 10 h after the interaction between H9N2 virus and chicken erythrocytes in vitro and 3, 7 and 14 d after H9N2 virus nasal infection of chicks.3. Expression levels of C1q, C4, C1s, C2, C3, C5, C7 and CD93 were significantly up-regulated at 2 h and significantly down-regulated at 10 h. Gene expression levels of C1q, C3ar1, C4a, CFD and C5ar1 were seen to be different at each time point. The expression levels of C1q, C4, C1s, C2, C3, C5, C7, CFD, C3ar1, C4a and C5ar1 were significantly up-regulated at 7 d and the gene expression of levels of C3, CD93 and C5ar1 were seen to be different at each time point.4. The results confirmed that all the complement-associated genes were expressed in chicken erythrocytes and showed the H9N2 virus interaction with chicken erythrocytes and subsequent regulation of chicken erythrocyte complement-associated genes expression. This study reported, for the first time, the relationship between H9N2 and complement system of chicken erythrocytes, which will provide a foundation for further research into the prevention and control of H9N2 infection.

[Progress in the treatment of refractory macular hole by human amniotic membrane].

The surgery of refractory macular hole is often very tough for its uncertain prognosis. There is no unified definition for refractory macular hole, which usually refers to macular hole with a long duration, large diameter, or failure of initial operation. Treatment success can be achieved in some cases by expanding the range of internal limiting membrane peeling or filling with autologous tissue. Human amniotic membrane is a kind of tissue with strong anti-inflammatory and anti-fibrosis effects, and has been widely used in the treatment of ocular surface diseases. In recent years, amniotic membrane has been used in treating refractory macular hole. Some positive results have been achieved, including improvement of postoperative macular structure and increase of visual function. This review focuses on the mechanism, efficacy and prospect of human amniotic membrane in the treatment of refractory macular hole, providing reference for clinical practice and research.

[Epidemiological characteristics of herpes zoster in Xicheng district of Beijing in 2019: based on the health information system of medical institutions].

Objective: Using data of health information system (HIS) of medical institutions to study epidemiological characteristics of herpes zoster in Xicheng district of Beijing. Methods: To collect data of outpatient herpes zoster cases of all 42 medical institutions in 2019 based on HIS. After distinguishing the reduplicated cases, we organized these data for descriptive epidemiological analysis. Results: A total of 3 982 primary outpatient cases were investigated, the estimated incidence was 3.38‰ (3 982/1 178 999). The incidence was 2.90‰ (1 655/570 320) for males and 3.82‰ (2 327/608 679) for females and with increasing trends with age. Herpes zoster occurred from January to December. These cases mainly visited tertiary hospitals, with central departments as dermatology and traditional Chinese medicine involved. For the first identified cases, the average age was (60.48±15.43) years old. The ages of disseminated herpes zoster patients was (74.00±8.98) years old, while the age of herpes zoster in the outer ear was (54.32±15.73) years old. The top three diseases were herpes zoster, post-herpetic neuralgia, and Herpes zoster with other neurological complications, with proportions as 82.65% (3 291/3 982), 10.37% (413/3 982), and 4.37% (174/3 982), respectively. Conclusions: Most herpes zoster cases were more than 50 years old in Xicheng district of Beijing, with females have seen more than males. Complications commonly occurred among individuals more than 50 years old and with the most widely seen complication as post-herpetic neuralgia.

[Association between platelet parameters and risk for stroke in people with different blood pressure levels: Dongfeng-Tongji cohort].

Objective: To explore the associations of platelet parameters platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW) and plateletcrit (PCT) with the risk for stroke in people with different blood pressure levels. Methods: All the participants were from Dongfeng-Tongji cohort, including 38 295 retired employees from Dongfeng Motor Corporation at the first follow-up survey. After excluding participants with coronary heart disease, stroke, cancer, history of platelet influential drug use and those with missed data of platelet parameters or blood pressure or lost to follow-up, finally a total of 21 294 participants were included in this study. All the participants completed baseline questionnaires, physical examinations, clinical biochemical tests, and blood sample collection. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and the corresponding 95% confident intervals (CIs) for the associations between platelet parameters and risk for stroke in people with different blood pressure levels. Results: After a mean follow-up of 8.0 years, 1 578 participants developed incident stroke [1 266 ischemic stroke (IS) cases and 312 hemorrhagic stroke (HS) cases]. Compared with the participants with PLT<188×109/L, those with PLT≥188×109/L among hypertension cases were significantly associated with higher risks for stroke and IS (stroke: HR=1.27, 95%CI: 1.12-1.44; IS: HR=1.39, 95%CI: 1.21-1.60). Among hypertension group, compared with participants with PCT<0.165%, PCT≥0.165% were significantly associated with higher risk for stroke (HR=1.15, 95%CI: 1.01-1.30) and lower risk for HS (HR=0.70, 95%CI: 0.53-0.93); Among non-hypertension and hypertension group, PCT ≥0.165% were significantly associated with higher risks of IS (HR=1.27, 95%CI: 1.05-1.54; HR=1.31, 95%CI: 1.14-1.50). MPV and PDW were not significantly associated with risk for stroke. Risk for stroke increased significantly in hypertension cases with different platelet parameters levels compared with non-hypertension cases with lower levels of each platelet parameters. Conclusion: Higher levels of PLT and PCT could increase the risks for stroke and IS in middle-aged and elderly hypertension patients, and lower levels of PCT could decrease the risk for HS in hypertension patients.

[Evaluation the application of intra-operative cell salvage in cesarean section based on multicenter data].

Objective: To investigate the safety, efficacy and application indication of intra-operative cell salvage (IOCS) in cesarean section. Methods: A total of 1 265 pregnant women who received IOCS blood transfusion during cesarean section in 11 tertiary A hospitals from August 2016 to January 2019 were collected and divided into <1 500 ml group (796 cases) and ≥1 500 ml group (469 cases) according to the amount of blood loss during cesarean section. The general clinical data, ultrasonic imaging data, perinatal and puerperium indicators were analyzed retrospectively. The risk factors of intraoperative blood loss ≥1 500 mL using IOCS transfusion were analyzed by logistic multivariate regression. Results: (1) A total of 848 001 ml of blood was recovered and a total of 418 649 ml of blood was transfused in 1 265 pregnant women who received IOCS transfusions, which was equivalent to 23 258 U red blood cell suspension, greatly saving medical resources. The intraoperative blood loss in <1 500 ml group and ≥1 500 ml group was 800 ml (300-1 453 ml) and 2 335 ml (1 500-20 000 ml), respectively. No amniotic fluid embolism, severe adverse reactions, shock and death occurred in the two groups. (3) Multivariate regression analysis showed that age ≥35 years (OR=1.5, 95%CI: 1.1-1.9), prenatal hemoglobin level <110 g/L (OR=1.7, 95%CI: 1.3-2.2), history of uterine surgery (OR=1.8, 95%CI: 1.3-2.6), placenta previa (OR=1.9, 95%CI: 1.1-3.1), placenta accreta (OR=2.6, 95%CI: 1.8-3.9), blood pool in the placenta (OR=1.6, 95%CI: 1.1-2.3), abnormal posterior placenta muscle wall (OR=1.8, 95%CI: 1.2-2.6), placenta projecting to the anterior uterine wall (OR=3.0, 95%CI: 1.3-7.0) were risk factors for blood loss ≥1 500 ml in obstetric transfusion using IOCS technique, with statistical significance (all P<0.05). Conclusion: IOCS is safe and effective in cesarean section, which could save the medical resources and reduces medical expenses, however, it is necessary to strictly master the application indication.

[QARS1 gene related glutaminyl-tRNA synthetase deficiency syndrome: report of three cases and a review of literature].

Objective: To investigate the clinical characteristics, treatment and prognosis of QARS1 gene related glutaminyl-tRNA synthetase deficiency. Methods: To summarize and analyze the clinical manifestations, imaging, laboratory examination, genetic variant characteristics and treatment of three patients from the Fujian Medical University Affiliated Union Hospital, the 900th Hospital of People's Liberation Army, the First Medical Center of People's Liberation Army General Hsopital carrying compound heterozygous variations in QARS1 gene with a long-term follow-up in China. A literature search was conducted using Wanfang, Weipu, China National Knowledge Infrastructure (CNKI) and Pubmed databases with the keywords "QARS", "QARS1" and "glutaminyl-tRNA Synthetase"(up to December 2019). Results: Case 1, a female 53 days of age, was admitted to the Fujian Medical University Affiliated Union Hospital for treatment because of the complaint of repetitive seizures for one month after birth and fever for one day. The seizure occurred within the first 2 hours of life with multiple forms and often had a status as persisted from hours to days. The seizures were resistant to many anti-epilepsy drugs (AED) and ketogenic diet but later controlled by clonazepam. However, she died at the age of seven years. Case 2 (younger brother of case 1), a one-hour-old boy, was hospitalized because of seizures after birth for 1 hour. Intrauterine growth retardation was discovered during late-pregnancy. The boy presented seizures and microcephaly immediately after birth, and his epilepsy was pharmacoresisitant. Case 3, an 8-month-old girl, was admitted due to recurrent convulsions for nearly two months. The girl had mild developmental retardation and hypotonia after birth. The infantile spasm was observed at her age of 6 months and disappeared under treatment with Vitamin B6, vigabatrin combined with adreno-cortico-tropic-hormone and magnesium sulfate. However, the seizure pattern turned to tonic seizures later. She was seizures free now with clobazam and zonisamide treatment. All of them manifested as a syndrome composed of severe global developmental retardation, progressive microcephaly, hypotonia from the very beginning, mild hypoproteinemia and diffuse brain atrophy. Genetic studies revealed compound heterozygous variations of QARS1 gene which were not reported previously. A review of the literature reported a total of 22 patients from 18 unrelated families all over the world. Except for 5 cases without epilepsy,all the patients shared very similar clinical manifestations as classic pentalogy. The recommended effective treatment for epilepsy has not been reported yet. Conclusions: Glutaminyl-tRNA synthetase deficiency caused by QARS1 gene variations manifested as a clinical syndrome's pentalogy, characterized by microcephaly, cerebral atrophy, intractable early-onset epileptic encephalopathy, global developmental retardation and severe muscle hypotonia.

Optical fiber surface waveguide with Fabry-Perot cavity for sensing.

A parallel structured optical fiber Fabry-Perot interferometer sensor is proposed and demonstrated for refractive index and strain sensing with low temperature cross sensitivity. The device consists of two Fabry-Perot cavities fabricated by a femtosecond laser: one is inscribed in the fiber surface waveguide and used for sensing, and the other one is located in the fiber core for referencing. Part of the light propagating in the fiber core can be directed to the fiber surface waveguide via an X coupler. Because of the evanescent field, the light traveling along the fiber surface waveguide interacts with the surrounding medium and enables external refractive index sensing. The measurement sensitivity of the device is enhanced due to the Vernier effect associated with the parallel structured two Fabry-Perot interferometers. The sensitivities of ∼843.3nm/RIU and ∼101.8pm/µÎµ have been obtained for refractive index and strain, respectively, and the corresponding temperature cross sensitivities are ∼9.6×10-6RIU/∘C and ∼7.956×10-2µÎµ/∘C, respectively. The device is featured with high robustness, compact size, and large sensitivity.

Silencing of miR-330-5p stimulates osteogenesis in bone marrow mesenchymal stem cells and inhibits bone loss in osteoporosis by activating Bgn-mediated BMP/Smad pathway.

OBJECTIVE: To illustrate the role of micro ribonucleic acid (miR)-330-5p in regulating osteogenesis through biglycan (Bgn)-mediated bone morphogenetic protein (BMP)/Smad pathway. MATERIALS AND METHODS: A mouse model of osteoporosis (OP) was established by ovariectomy (OVX). BMD and miR-330-5p levels in mice undergoing sham operation or OVX were determined. BMD and BV/TV in OP mice with in vivo knockdown of miR-330-5p were measured by Micro-CT. After silencing of miR-330-5p in mouse primary bone marrow stromal cells (BMSCs), expression changes in osteogenesis-associated genes, ALP activity, and mineralization ability were assessed. Subsequently, the interaction between miR-330-5p and Bgn was examined by Dual-Luciferase reporter gene assay and Western blotting. Then, Bgn levels in BMSCs undergoing osteogenesis at different time points were measured. At last, the regulatory effects of miR-330-5p/Bgn axis on the BMP/Smad pathway, ALP activity, and mineralization ability in BMSCs were evaluated. RESULTS: BMD was decreased and miR-330-5p was upregulated in OP mice. OP mice with in vivo knockdown of miNA-330-5p presented higher BMD and BV/TV than controls. Transfection with miR-330-5p inhibitor upregulated osteogenesis-associated genes, ALP activity, and mineralization ability in BMSCs. Bgn was time-dependently upregulated in BMSCs undergoing osteogenesis, which was indicated to be the target gene of miR-330-5p. Besides, Bgn level was negatively regulated by miR-330-5p. Importantly, Bgn was able to reverse the regulatory effects of miR-330-5p on the BMP/Smad pathway, ALP activity, and mineralization ability in BMSCs. CONCLUSIONS: Knockdown of miR-330-5p facilitates osteogenesis in BMSCs through the Bgn-induced BMP/Smad pathway, thus alleviating the progression of OP.

[Association of polycyclic aromatic hydrocarbon exposure and CYP1A1 gene and enzyme activity of peripheral blood monocyte cells in coke oven workers].

Objective: To explore the association between polycyclic aromatic hydrocarbons (PAHs) exposure and cytochrome P450 CYP1A1 expression at gene and enzyme activity levels in the peripheral blood monocyte cells in coke oven workers, and to provide a certain basis for the biological monitoring of health damage in coke oven workers. Methods: We surveyed 118 coke oven workers and 63 controls (energy power workers in the same company) using self-designed questionnaire, determined their post-shift urinary 1-hydroxypyrene (1-OH-Py) concentration using high performance liquid chromatography (HPLC)-fluorescence detector method. We also isolated the peripheral blood mononuclear cell (PBMC) from fasting venous blood, and detected DNA damage using comet assay, CYP1A1 mRNA level using the real-time fluorescent quantitative PCR (FQ-PCR), and EROD activity using spectrophotometry. Statistical analyses including one-way analysis of variance and multiple linear regressions were used to analyze the association of urinary 1-OH-Py and CYP1A1 mRNA level and EROD activity. Results: Compared to the control group, the urinary 1-OH-Py concentration and PBMC DNA tail moment were significantly increased in coke oven workers (P<0.05), and CYP1A1 gene level and EROD activity in PBMC were significantly decreased (P<0.05). Multiple linear regression showed that a ten-fold increase of urinary 1-OH-Pycon centration was associated with a decrease of 0.77 (95%CI: -1.33--0.21) in CYP1A1 gene level, and a decline of 0.15 (95%CI: -0.76--0.16) in EROD activity of PBMC in coke oven workers (P<0.05). Conclusion: Occupational PAHs exposure induced DNA damage, which was associated with the decreased level in CYP1A1 gene cavel and EROD activity in PBMC of coke oven workers.

[Impact of informal e-waste recycling on human health].

Increasing e-waste has become a major problem for global environment and public health. In the process of dismantling and recycling of disordered electronic waste, heavy metals such as lead and brominated flame retardants and organic substances are released into environmental media such as air, soil, dust and water, which is harmful to the health of local residents. Taking an e-waste dismantling area in Guangdong Province as an example, this paper reviews exposure levels of heavy metals and organic matters in e-waste recycling areas in China, as well as the health effects of local residents. Previous studies have found that e-waste recycling activities led to serious environmental pollution and high exposure levels of heavy metals and organic matters in local residents, which has a certain impact on the physiological functions of various human systems. The establishment of a centralized dismantling zone can effectively reduce the load level of various pollutants.

Role of microRNA-218-5p in the pathogenesis of chronic obstructive pulmonary disease.

OBJECTIVE: Chronic obstructive pulmonary disease (COPD) is an inflammatory lung disease characterized by inflammatory cell activation and the release of inflammatory mediators. By measuring microRNA expression in the plasma of COPD subjects, we aimed to identify the clinical relevance of plasma miRNA levels in these patients. PATIENTS AND METHODS: A total of 40 COPD patients and 40 healthy controls were enrolled in the study. The COPD model of C57BL/6 mice was also developed by exposing them to cigarette smoke (CS). The expression of microRNA-218-5p was detected by qRT-PCR in all the subjects and mice. The serum level of IL-18 and TGF-ß1 was also detected via ELISA kit. To investigate the effects of miR-218-5p, 10 mg/kg of miR-218-5p inhibitor (miR-218-5p antagonist), a scrambled control or PBS (solvent) was intranasally administered on the first and the fourth exposure day, before the start of CS exposure. RESULTS: The results showed that miR-218-5p was significantly down-regulated in patients with COPD, compared to normal subjects. There was a negative correlation between the plasma miR-218-5p level and the duration of disease since diagnosis in COPD ex-smokers. CS-induced COPD mice experiments with a miR-218-5p inhibitor demonstrated a protective role of miR-218-5p in cigarette smoke-induced inflammation and COPD. CONCLUSIONS: These findings supported that miR-218-5p may, therefore, play an important role in the pathogenesis of COPD.

A novel flow sensor based on resonant sensing with two-stage microleverage mechanism.

The design, simulation, fabrication, and experiments of a novel flow sensor based on resonant sensing with a two-stage microleverage mechanism are presented in this paper. Different from the conventional detection methods for flow sensors, two differential resonators are adopted to implement air flow rate transformation through two-stage leverage magnification. The proposed flow sensor has a high sensitivity since the adopted two-stage microleverage mechanism possesses a higher amplification factor than a single-stage microleverage mechanism. The modal distribution and geometric dimension of the two-stage leverage mechanism and hair are analyzed and optimized by Ansys simulation. A digital closed-loop driving technique with a phase frequency detector-based coordinate rotation digital computer algorithm is implemented for the detection and locking of resonance frequency. The sensor fabricated by the standard deep dry silicon on a glass process has a device dimension of 5100 µm (length) × 5100 µm (width) × 100 µm (height) with a hair diameter of 1000 µm. The preliminary experimental results demonstrate that the maximal mechanical sensitivity of the flow sensor is approximately 7.41 Hz/(m/s)2 at a resonant frequency of 22 kHz for the hair height of 9 mm and increases by 2.42 times as hair height extends from 3 mm to 9 mm. Simultaneously, a detection-limit of 3.23 mm/s air flow amplitude at 60 Hz is confirmed. The proposed flow sensor has great application prospects in the micro-autonomous system and technology, self-stabilizing micro-air vehicles, and environmental monitoring.

[Application of uterine lower part breakwater-like suture operation in placenta previa].

Objective: To explore the efficacy and safety of uterine lower posterior wall breakwater-like suture technique in controlling the intraoperative bleeding of placenta previa. Methods: From June 2016 to June 2017, 47 patients were diagnosed placenta previa in Union Hospital, Tongji Medical College of Huazhong University of Science and Technology. Posterior wall breakwater-like suture technique was used preferentially, as for cases with poor myometrium layer, lower anterior wall stitch suture was used at the same time. Bilateral descending branches of uterine artery ligation and Cook balloon compression of uterine lower segment was conducted when necessary. The clinic data of the 47 cases were analyzed. Results: Thirty cases (63.8, 30/47) were diagnosed placenta inccreta or percreta by ultrasound or MRI preoperatively. Senventeen cases were diagnosed as placenta accreta (36.2%, 17/47) . Thirty-four cases had the previous history of cesarean section. The average cervical canal length of 47 patients was (2.8±0.9) cm. There were 19 cases (40.4%,19/47) with 1 time posterior wall breakwater-like sutured and 16 cases (34.0%,16/47) with 2 or 3 times posterior wall breakwater-like sutured; 12 cases (25.5%,12/47) were treated with anterior wall stitch suture simultaneously.Ten cases (21.3%, 10/47) underwent uterine artery ligation, 17 cases (36.2%, 17/47) underwent COOK balloon compression on the staxis surface of lower segment. None of them had postpartum hemorrhage or performed internal iliac artery embolization. The median blood loss in the operation was 700 ml, the percentiles 25 was 500 ml, and the percentiles 75 was 1 200 ml. The blood loss ≥1 000 ml in 18 (38.3%, 18/47) patients,and the most serious one was 2 500 ml. The median blood transfusion volume (including allogenetic transfusion and autotransfusion) was 450 ml, the percentiles 25 was 228 ml, and the percentiles 75 was 675 ml. The average vaginal bleeding volume was (150±63) ml first day after operation. The mean hospitalization time was (4.7±1.0) days. The mean gestational weeks of pregnancy termination was (36.1±1.5) weeks, and the mean birth weight of newborns was (2 817±492) g. Apgar score:1-minute 7.8±1.1, 5-minute 8.9±0.8. No neonatal death, 16 cases were transferred to neonatal ICU (34.0%, 16/47) mainly for premature delivery and low birth weight. No complication was found in 6 months post-operation. Conclusions: Uterine posterior wall breakwater-like suture technique is a simple, safe and effective way in controlling intraoperative bleeding of placental previa.Lower anterior wall stitch suture could effectively stop bleeding and restore the normal uterine shape. Combined application of various methods could significantly reduce the incidence of postpartum hemorrhage and hysterectomy, and improve maternal and fetal prognosis.

[Preliminary study on reading speed test with IReST for normally-sighted young Chinese readers].

Objective: To assess the reading speed of normally-sighted young Chinese with the International Reading Speed Texts (IReST) Chinese version, and evaluate the normal range of the texts, the equivalence of the ten different texts and the potential clinical value. Methods: Evaluation of diagnostic techniques. Participants aged 18 to 35 years old with junior high school or above education and best corrected visual acuity no less than 0.6 were recruited. Best corrected visions of both eyes and binocular vision were tested, and ocular and nervous system diseases were excluded with slit-lamp microscope and funduscope. All the ten texts were read aloud at a distance of 40cm one by one according to a random sequence for each participant. Reading speeds were calculated based on the reading time measured with a stopwatch and number of characters read correctly. The procedure was repeated once again a week later. Data were collected with Epidata and further analyzed with R software. Data accorded with normal distribution and homogeneity of variance were compared by t-test, or by rank sum test. Results: One hundred and three volunteers aged (26.0±2.8) years old participated in the survey. Among them, 66% were female, 96.1% had college education, 53.4% wear glasses in daily life. The best corrected vision of both distance and near were 1.0 (decimal). For the first test, average reading speed for all the participants and texts was (295±51) characters/min,much faster than the normal range provided by the reading cards. No significant difference was found between different texts, and the biggest variance between texts was 11 characters/min(P>0.05). The average reading speed of the second test was (315±53) characters/min, which was faster than the first one (P<0.05) . No statistic relationship was found between reading speed and age, education level or wearing of glasses. However, women read faster than men, and significant difference was found between male and female volunteers in 5 texts during the first test. Conclusions: Normally-sighted young Chinese readers read faster than the normal range provided by IReST cards. There is significant variance of reading speed between different individuals. Although learning effect due to the repeated tests should be considered, the ten texts are of favorable consistency. IReST can be a useful tool for assessing reading performance, especially for comparing results before and after interventions with different texts. (Chin J Ophthalmol, 2018, 54: 120-124).

Visualization and automatic detection of defect distribution in GaN atomic structure from sampling Moiré phase.

Quantitative detection of defects in atomic structures is of great significance to evaluating product quality and exploring quality improvement process. In this study, a Fourier transform filtered sampling Moiré technique was proposed to visualize and detect defects in atomic arrays in a large field of view. Defect distributions, defect numbers and defect densities could be visually and quantitatively determined from a single atomic structure image at low cost. The effectiveness of the proposed technique was verified from numerical simulations. As an application, the dislocation distributions in a GaN/AlGaN atomic structure in two directions were magnified and displayed in Moiré phase maps, and defect locations and densities were detected automatically. The proposed technique is able to provide valuable references to material scientists and engineers by checking the effect of various treatments for defect reduction.