[In vitro optical assessment of three types of non-diffractive extended depth-of-focus intraocular lenses].

Objective: To evaluate the in vitro optical performance of three types of non-diffractive extended depth-of-focus (EDoF) intraocular lenses (IOLs). Methods: Experimental study. Three Vivity IOLs, three Eyhance IOLs, and three ES60 IOLs were included. The professional optical bench OptiSpheric® IOL PRO 2 and an ISO-2 corneal model were applied. The through-focus modulation transfer function (MTF) and predicted visual acuity (logarithm of the minimum angle of resolution) of different spatial frequencies and different focuses under apertures of 3.0 mm and 4.5 mm were recorded. The aspheric monofocal (Tecnis ZCB00), diffractive EDoF (Tecnis Symfony), and trifocus (STF1) IOLs, as well as the lowest visual requirement criteria of EDoF IOLs of American Academy of Ophthalmology served as assessment controls. Results: For the 3.0-mm aperture, the peak value of the MTF was highest with ZCB00, followed by Eyhance, ES60, Vivity, Symfony, and STF1. All experimental non-diffractive EDoF IOLs had two MTF peaks, and the distance between both peaks was longest with Vivity (1.76 D), followed by ES60 (1.43 D) and Eyhance (1.36 D). Among the control IOLs, Symfony had two MTF peaks, and the peak MTF of the intermediate focus was highest. STF1 had three MTF peaks, and the peak MTF of the near focus was highest. For the 4.5-mm aperture, the ranking of the MTF peak of the six types of IOLs was the same as that for the 3.0-mm aperture. Vivity had an increased MTF peak of the distance focus, but a decreased intermediate focus MTF peak, while the MTF peaks of the distance, intermediate, and near focuses in the other IOLs decreased, compared to those for the 3.0-mm aperture. The predicted visual acuity of the distance focus of the three types of non-diffractive EDoF IOLs was all better than 0.0. The predicted visual acuity of the intermediate focus of the Vivity IOL and the ES60 IOL was 0.11 and 0.05 better than that of the Eyhance IOL, respectively. Based on the predicted visual acuity of 0.2, Vivity and ES60 had a depth of focus of at least 0.50 D exceeding ZCB00, while Eyhance had a depth of focus of 0.40 D exceeding ZCB00. Conclusions: In the experiments in vitro, the three types of non-diffractive EDoF IOLs exhibited varying degrees of intermediate to near focus optical performance while maintaining distance focus optical performance. The Eyhance IOL showed better distance focus optical performance than ES60 and Vivity IOL. The Vivity IOL and the ES60 IOL showed better depth of focus extensions than the Eyhance IOL and met the lowest visual requirement criteria of EDoF IOLs of American Academy of Ophthalmology.(This article was published ahead of print on the Online-First Publishing Platform for Excellent Scientific Researches of Chinese Medical Association Publishing House on April 29, 2024).

[Accuracy comparison of total keratometry and standard keratometry in intraocular lens power calculations for post-corneal refractive surgery cataract patients].

Objective: To compare the accuracy of intraocular lens (IOL) power calculations using total keratometry (TK) versus standard keratometry (K) in post-corneal refractive surgery cataract patients. Methods: This retrospective case series study included 30 patients (36 eyes) with a history of laser corneal refractive surgery who underwent cataract extraction and IOL implantation at Qingdao Eye Hospital, Affiliated to Shandong First Medical University, from September 2022 to December 2023. The cohort comprised 16 males and 14 females, with an average age of (53.6±8.1) years. IOL power was calculated using the K-based Haigis-L and Barrett True-K formulas, as well as the TK-based Haigis and Barrett Universal Ⅱ formulas. Postoperative objective refraction was performed to obtain the actual refractive status of the operated eyes. The refractive prediction error (RPE) was defined as the difference between the actual spherical equivalent and the predicted refraction. The absolute value of the RPE was taken as the refractive absolute error (RAE). Differences in errors calculated by the four formulas were compared. Results: TK showed good consistency with K, with TK being on average 0.50 D lower than K. Analysis of variance revealed statistically significant differences in RPE among the four formulas (P<0.001). The RPE for the TK-based Haigis formula was (0.17±0.09) D, and for the Barrett Universal Ⅱ formula, it was (0.21±0.11) D, both significantly better than the K-based Haigis-L formula (-0.61±0.12) D and Barrett True-K formula (-0.57±0.11) D (all P<0.001). The percentage of eyes with postoperative RPE<±1.00 D was higher for the TK-based Haigis (92%, 33 eyes) and Barrett Universal Ⅱ (86%, 31 eyes) formulas compared to the TK-based Barrett True-K (75%, 27 eyes) and Haigis-L formulas (67%, 24 eyes), with statistically significant differences (P<0.05). Conclusions: Compared with K, TK improves the accuracy of IOL power calculation in post-corneal refractive surgery patients. Both the TK-based Barrett Universal Ⅱ and Haigis formulas demonstrate high accuracy.

[Efficacy and short-term outcomes of myocardial protection using single-dose histidine-tryptophan-ketoglutarate cardioplegia during aortic root surgery with different duration of myocardial ischemia].

Objective: To explore the efficacy of myocardial protection with single-dose histidine-tryptophan-ketoglutarate (HTK) cardioplegia during aortic root operation, and the correlation between short-term clinical outcomes and duration of myocardial ischemia. Methods: The data of clinical cases undergoing myocardial protection with single-dose HTK cardioplegia during aortic root operation from January 2018 to December 2022 were retrospectively reviewed. Patients were divided into conventional HTK cardioplegia group (<3 h) and prolonged HTK cardioplegia group (≥3 h) according to duration of intraoperative myocardial ischemia. A 1∶1 propensity score matching was performed and the correlations between duration of myocardial ischemia and postoperative short-term outcomes (30-day mortality, readmission, mechanical circulation support and renal insufficiency) were analyzed. Results: A total of 282 patients were included in the final analysis, with 210 cases in the conventional HTK cardioplegia group and 72 cases inthe prolonged HTK cardioplegia group before matching. After matching, there were 64 cases (53 males and 11 females) in the conventional HTK cardioplegia group, with a mean age of (49.4±14.2) years. The prolonged HTK cardioplegia group had 64 cases (55 males and 9 females), with a mean age of (50.5±12.3) years. Higher sensitivity troponin [12 h: 10.1 (4.6, 18.7) µg/Lvs 4.1(2.2, 8.6) µg/L, P=0.002; 24 h: 7.7 (4.5, 19.0) µg/L vs 4.8 (2.2, 11.9) µg/L, P=0.025] and creatine kinase isoenzyme[12 h: 46.3 (28.1, 62.4) µg/L vs 20.7(14.1, 32.9) µg/L, P<0.001; 24 h: 26.3(13.4, 49.2) µg/L vs 14.5 (10.1, 33.5)µg/L, P=0.011] after surgery was detected in prolonged HTK cardioplegia group. Comparisons of other primary and secondary endpoint events showed no significant differences between the two groups (all P>0.05). Multivariate binary logistic regression showed that duration of myocardial ischemia had no significant effect on postoperative 30-day mortality (OR=1.255, 95%CI: 0.500-3.148, P=0.629), 30-day readmission (OR=0.378, 95%CI: 0.069-2.065, P=0.261) and mechanical circulation support (OR=0.991, 95%CI: 0.331-2.970, P=0.998). Conclusion: During aortic root surgery, single-dose HTK cardioplegia may provide satisfactory myocardial protection, and there was no significant correlation between duration of myocardial ischemia and short-term clinical outcomes.

[Comparison of formulas for intraocular lens power calculation after corneal refractive surgery].

Objective: To evaluate the accuracy of five intraocular lens (IOL) power calculation formulas for calculating IOL power in patients with previous myopia-corrected corneal refractive surgery. Methods: In this case series study, a total of 30 eyes of 30 patients who had excimer laser corneal refractive surgery for myopia and subsequent cataract surgery in Qingdao Eye Hospital from April 2020 to October 2022 were included. The Pentacam anterior segment analysis system and IOLMaster were used to measure ocular parameters, including axial length, anterior chamber depth, keratometry, lens thickness, and mean true net power (mTNP). Five formulas were used for IOL power calculation: Shammas formula, Olsen formula, SRK/T (mTNP) formula, Haigis-L formula, and Barrett True-K formula. After cataract extraction, we obtained the actual postoperative refraction by measuring the objective refraction. The prediction error was determined as the difference between the actual postoperative refraction and the predicted refraction, and the absolute value of the prediction error was the absolute error. The differences in the calculation errors of the 5 formulas were compared. Results: Regarding the prediction errors, the results of the SRK/T (mTNP) and Olsen formulas were better than those of Shammas and Haigis-L, and the differences were statistically significant (all P<0.05). The proportion of eyes with an absolute error of 0.50 D for Barrett True-K was highest (70%, 21/30), followed by the SRK/T (mTNP) formula (67%, 20/30). The proportions of eyes with an absolute error within 1.00 D for Barrett True-K, SRK/T (mTNP), and Olsen were all over 80%, with 24 eyes, 24 eyes, and 25 eyes, respectively. Conclusions: The Barrett True-K formula showed high accuracy in predicting the refraction after cataract extraction in patients with a history of corneal refractive surgery for myopia. The calculation result of the Haigis-L formula was highly unstable.

[Safety and efficacy of toric intraocular lens implantation for more than 5 years].

Objective: To evaluate the clinical safety and efficacy of toric intraocular lens (IOL) implantation for more than 5 years. Methods: This study was a prospective cohort study in which subjects were continuously observed over a two-year period (May 2014 to May 2016) in nine hospitals. The study randomly assigned subjects to two groups using a central dynamic randomization system: the study group, which received Proming® IQ toric IOL implants, and the control group, which received AcrySof® IQ toric IOL implants. The subjects completed a one-year follow-up, during which various measures were taken and evaluated, including visual acuity, IOL rotation, postoperative complications, intraocular pressure, and subjective evaluation (preoperatively and at 1 day, 6 months, 1 year, and 5 years post-surgery). The main statistical analysis methods include the Mann-Whitney U test, independent sample t-test, Wilcoxon signed rank test, paired sample t-test, chi-square test, and Fisher's exact test. Results: A total of 45 eyes (26 in the study group and 19 in the control group) completed the five-year continuous observation period. The mean age of the subjects was (72.07±10.67) years and the mean interval from surgery to the last visit was (5.39±0.47) years. After five years, there were no significant differences in uncorrected distance visual acuity (0.20±0.26 vs. 0.16±0.13, t=0.17,P=0.752), best corrected distance visual acuity[0.00(0.00, 0.20) vs. 0.05±0.10, U=188.00, P=0.880], uncorrected near visual acuity[0.50 (0.20, 0.60) vs. 0.42±0.20, t=0.35, P=0.857], and best corrected near visual acuity (0.13±0.16 vs. 0.17±0.23, U=161.00, P=0.884) between the two groups. However, all measures improved significantly from baseline levels in both groups (all P<0.05). Five years after surgery, no matter objective refraction [(-0.67±0.85) D vs. (-0.73±1.08)D] or subjective refraction[-0.50 (-1.00, 0.00)D vs. (0.69±0.87)D], the degree of cylindrical degree is significantly lower than preoperative corneal astigmatism [(1.27±0.49) D vs. (1.34±0.82) D, all P<0.001]. In addition, there were no significant differences in intraocular pressure, subjective evaluation of visual adverse symptoms, distance vision spectacle independence, or overall satisfaction evaluation between the two groups (all P>0.05). The IOL rotation was 3.0°(1.0°, 6.0°) in the study group and 4.0°(2.0°, 6.0°)in the control group (U=185.50,P=0.574), indicating no significant difference between the groups in terms of rotational stability. Five years after surgery, there were 7 cases of posterior capsular opacification in the study group and 4 cases in the control group. There were no cases of IOL glistening in the study group, but 5 cases (26.32%) were observed in the control group. Conclusions: The long-term effects of Proming® toric IOL implantation in correcting cataracts with regular corneal astigmatism are clear after five years, with few complications and stable results.

Outcomes of intensification of induction chemotherapy for children with high-risk acute myeloid leukemia: A report from the Children's Oncology Group.

BACKGROUND: High-risk pediatric acute myeloid leukemia confers a poor prognosis, and alternative strategies are needed to improve outcomes. We hypothesized that intensifying induction on the AAML1031 clinical trial would improve outcomes compared to the predecessor trial AAML0531. METHODS: Patients on AAML0531 received cytarabine (1600 mg/m2 )/daunorubicin (150 mg/m2 )/etoposide (ADE) for induction II and patients on AAML1031 received mitoxantrone (48 mg/m2 )/cytarabine (8000 mg/m2 ) (MA). Stem cell transplant (SCT) conditioning included busulfan/cyclophosphamide on AAML0531, whereas AAML1031 used busulfan/fludarabine and liberalized donor eligibility. Patients were included in this analysis if they met high-risk criteria common to the two trials by cytogenics or poor disease response after induction I ADE. RESULTS: MA provided no benefit over ADE at: induction II response (complete response [CR]: 64% vs. 62%, p = .87; measurable residual disease [MRD]+: 57% vs. 46%, p = .34); or intensification I response (CR: 79% vs. 94%, p = .27; MRD+: 27% vs. 20%, p = 1.0). When considered with altered SCT approach, MA did not improve 5-year disease-free survival (24% ± 9% vs. 18% ± 15%, p = .63) or 5-year overall survival (35% ± 10% vs. 38% ± 18%, p = .66). MA was associated with slower neutrophil recovery (median 34 vs. 27 days, p = .007) and platelet recovery (median 29 vs. 24.5 days, p = .04) and longer hospital stay (32 vs. 28 days, p = .01) during induction II. CONCLUSION: Intensification of induction II did not improve treatment response or survival, but did increase toxicity and resource utilization. Alternative strategies are urgently needed to improve outcomes for pediatric patients with high-risk acute myeloid leukemia (trials registered at clinicaltrials.gov NCT01371981, NCT00372593).

[Clinical and experimental study of late postoperative opacification of hydrophilic acrylic intraocular lenses].

Objective: To analyze the cause of late postoperative opacification of hydrophilic acrylic intraocular lenses (IOLs) and the effect of IOL replacement surgery. Methods: This retrospective case series study comprised 15 eyes of 15 patients who were diagnosed as late postoperative opacification of hydrophilic acrylic IOLs from January 2019 to June 2020 at Qingdao Eye Hospital of Shandong First Medical University. The clinical data of patients were reviewed, and two IOLs were examined by scanning electron microscopy and energy dispersive X-ray spectroscopy. The intraoperative and postoperative complications of IOL replacement surgery were evaluated, and best corrected visual acuity was compared before and after surgery. Preoperative and postoperative data were compared using the paired t test. Results: The interval between the first IOL implantation and the detection of IOL opacification in 15 patients was (27.3±5.9) months. All the 15 patients had unilateral IOL opacification, and 9 patients had hypertension. Glycosylated hemoglobin A1c was significantly higher than the normal value in 4 of the 10 patients who underwent cataract surgery at our hospital. Confocal microscopy disclosed coralliform deposits on the superficial IOL optic. Scanning electron microscopy and energy dispersive X-ray spectroscopy showed the presence of calcium and phosphorus crystals in the opacification region of IOLs. Visual acuity in all 13 eyes receiving IOL exchange was significantly improved from 1.03±0.64 (logarithm of the minimum angle of resolution) to 0.39±0.21 (P<0.05). Posterior capsule rupture (4 eyes), new IOL implanted in the ciliary sulcus (3 eyes) and zonule breaking (1 eye) occurred during IOL replacement. Conclusions: IOL opacification is related with the IOL material and calcium ion concentration on the IOL surface. IOL replacement surgery can improve visual acuity safely and effectively. (Chin J Ophthalmol, 2021, 57: 512-518).

Effects of sarcopenia, hypoalbuminemia, and laparoscopic surgery on postoperative complications in elderly patients with colorectal cancer: A prospective study.

With the increasing number of elderly patients, the risk of diseases such as colorectal cancer (CRC) has increased. The objective of this prospective study was to explore the effects of sarcopenia, hypoalbuminemia, and laparoscopic surgery on postoperative complications among elderly patients who recently underwent colorectal surgery. Patients aged over 65 years who underwent surgery for CRC at the First Affiliated Hospital of Wenzhou Medical University were considered for this study. The demographical and clinical characteristics of these patients, as well as postoperative complications, were prospectively analyzed. The patients were divided into two groups depending on the diagnosis of sarcopenia, and the clinical variables corresponding to the two groups were compared. Further, the risk factors associated with postoperative complications were evaluated using univariate analysis and multivariate logistic regression analysis. A total of 360 patients fulfilled the inclusion criteria. Incidences of postoperative complications in the sarcopenia and non-sarcopenia groups were at 38.3% and 27.3%, respectively. In addition, sarcopenia (p=0.029) and hypoalbuminemia (p=0.010) were identified as independent risk factors, while laparoscopic surgery (p=0.023) was identified as a protective factor for postoperative complications. However, laparoscopic surgery was a protective factor for postoperative complications in the colon group only (p=0.001). Sarcopenia and hypoalbuminemia are independent risk factors that influence the probability of developing complications following CRC surgery. Laparoscopic surgery is a protective factor for postoperative complications of CRC patients, particularly colon cancer patients.

[CD38 dictates cardiac damage through mitochondrial apoptotic pathway under hypoxic-ischemic conditions].

Objective: To explore the mechanism of CD38-mediated cardiac damage under hypoxic-ischemic (H/I) conditions. Methods: Twenty CD38(-/-) male mice (8-week-old) and 20 wild-type (WT) male C57BL/6J mice (8-week-old) were randomly selected to construct the model of approximately 25% of the total body surface area (TBSA) burn injury. The cardiomyocytes (CMs) were separated from neonatal mice (1day) to construct the H/I injury model. Ad-CD38 adenovirus was transfected into CD38(-)/- primary CMs to callback CD38 expression. Animal experiments were grouped into WT-control group, CD38(-/-)-control group, WT-burn group, and CD38(-/-)-burn group (10 mice in each group). Primary CMs were divided into 6 groups: WT-normoxia group, CD38(-/-)-normoxia group, CD38(-/-)+Ad-CD38-normoxia group, WT-H/I group, CD38(-/-)-H/I group, CD38(-/-)+Ad-CD38-H/I group. The release of lactic dehydrogenase (LDH) from CMs and the cell viability were measured to estimate the level of myocardial injury. Ultrastructure of cardiomyocytes was examined by electron microscope. CD38 protein level and mitochondrial apoptosis-related proteins were detected by Western blot. Flow cytometry was used to detect mitochondrial reactive oxygen species (MitoSOX) of CMs under H/I condition. Cardiac function of mice was detected by ultrasonic apparatus. Results: (1) Animal experiments: The expression level of cardiac CD38 in WT-burn group was significantly higher than that in sham group (P<0.001). The heart function of CD38(-/-)-burn group was obviously better than WT-burn group [ejection fraction (EF)%: (84.70±2.31)% vs (76.10±2.96)%, shortening fraction (FS)%: (48.90±5.00)% vs (38.10±2.80)%] (both P<0.001). (2) Cell experiments: The expression level of cardiac CD38 in WT CMs under H/I condition was significantly higher than that in WT CMs under normoxia condition (P<0.05). The level of LDH, apoptotic cell and MitoSOX in CD38(-/-)-H/I group were fewer than WT-H/I group and CD38(-/-)+Ad-CD38(-)H/I group [(11.2±3.0)% vs (18.2±3.4)% and (17.6±4.0)%, (13.0±2.8)% vs (23.1±4.9)% and (23.3±6.0)%, (162±11)% vs (228±18)% and (220±18)%] (all P<0.001). The levels of cleaved-caspase3, Cytochrome-C in CD38(-/-)-H/I group were significantly lower than those in WT-H/I group and CD38(-/-)+Ad-CD38-H/I group (P<0.001). The cell viability in CD38(-/-)-H/I group was higher than that in WT-H/I group and CD38(-/-)+Ad-CD38-H/I group (0.355±0.043 vs 0.280±0.051 and 0.291±0.024) (all P<0.05). Electron microscopy results showed that structure of mitochondria in CD38(-/-)-H/I group was better than in WT-H/I group and CD38(-/-)+Ad-CD38-H/I group. Conclusion: Overexpression of CD38 contributes to cardiac damage by stimulating mitochondrial apoptotic pathway.

[Effect and mechanism of cardiac adipose triglyceride lipase overexpression on burn-induced cardiac injury].

Objective: To explore the effect and potential mechanism of cardiac adipose triglyceride lipase (ATGL) overexpression on burn-induced cardiac injury. Methods: Eight-week-old C57BL/6J mice with cardiac ATGL overexpression driven by the myosin heavy chain (MHC) promoter (MHC-ATGL burn group) and wild-type (wild-type burn group) mice were randomly chose to the following experiments with burn injury after 24 h (n=8/group), MHC-ATGL mice and wild-type mice with corresponded age and sex were included as control. Cardiac ATGL protein expression, serum levels of cardiac troponin T and cardiac kinase-MB (CK-MB), cardiac free fatty acid and reactive oxygen species were detected. The wild-type and MHC-ATGL burn groups were not only compared with their corresponded control groups, but also compared between each other. Results: The hair color and development were shown little difference between each group. ATGL protein expression is elevated in wild-type burn group (1.00±0.68 vs 3.09±0.93, P=0.023) and decreased in MHC-ATGL burn group (17.84±2.41 vs 10.36±2.22, P<0.001), while ATGL protein expression is still increased in MHC-ATGL burn group compared with wild-type burn group (P<0.001). Serum levels of cardiac troponin T and CK-MB were both elevated in wild-type burn group and MHC-ATGL burn group [(0.456±0.131) vs (0.076±0.019) µg/L and (0.219±0.089) vs (0.060±0.019) µg/L, (1 421±162) vs (221±67) U/L and (761±142) vs (221±41) U/L] (all P<0.001), while serum levels of cardiac troponin T and CK-MB was still decreased in MHC-ATGL burn group compared with wild-type burn group (P<0.001). In addition, cardiac free fatty acid was increased in wild-type burn group and little difference was found in MHC-ATGL burn group [(2.54±0.51) vs (0.46±0.27) mmol/L, P<0.001, and (0.81±0.38) vs (0.59±0.25) mmol/L, P=0.251], while cardiac free fatty acid was significant reduction in MHC-ATGL burn group compared with wild-type burn group (P<0.001). Levels of cardiac reactive oxygen species was both elevated in wild-type burn group and MHC-ATGL burn group [(1.89±0.23) vs (1.00±0.18) and (1.38±0.17) vs (0.95±0.13)] (both P<0.001), while levels of cardiac reactive oxygen was reduction in MHC-ATGL burn group compared with wild-type burn group (P<0.001). Conclusion: Cardiac ATGL overexpression may protect against burn-induced cardiac injury through reducing free fatty acid and reactive oxygen species production.

[Preliminary clinical observations of the effect of posterior continuous curvilinear capsulorhexis with intraocular lens optic capture in the treatment of pediatric cataract].

Objective: To observe the preliminary clinical effect of intraocular lens optic capture through posterior continuous curvilinear capsulorhexis in the treatment of pediatric cataract. Methods: It was a retrospective case series study. Forty-three eyes of 28 children underwent posterior continuous curvilinear capsulorhexis with posterior chamber intraocular lens optic capture to treat cataract from June 2017 to October 2018 in Qingdao Eye Hospital. Postoperative best corrected visual acuity, diopters, intraocular pressure, the position of intraocular lens, and postoperative complications were assessed. The distribution of preoperative and postoperative best corrected visual acuity was analyzed by Fisher's exact probability test. Results: Twenty-eight patients were 14 females and 14 males aged from 2 years old to 12 years old [mean age, (7±4) years]. All intraocular lenses were successfully captured in the posterior capsule. Patients were followed-up for 6.0 to 12.0 months (mean, 8.4 months). Except 2 eyes from one uncooperative child, the distribution of preoperative and postoperative best corrected visual acuity (<0.1, 0.1-<0.3, 0.3-<0.5, ≥0.5) had a significant difference (17, 17, 4, 3 eyes vs. 4, 4, 5, 28 eyes, P<0.01). At the last postoperative follow-up visit, the mean spherical equivalent was (0.21±0.74) D. Transient intraocular hypertension occurred in 3 eyes at 1 week after surgery and was controlled with stopping the use of corticosteroid eyedrops. No visual axis opacification or intraocular lens decentration or tilt was observed during the follow-up period. No other complications such as iris synechia, secondary glaucoma, retinal detachment, and cystoid macular edema were observed. Conclusions: Posterior continuous curvilinear capsulorhexis with intraocular lens optic capture is a safe and effective technique to treat pediatric cataract. It has a significant effect on the prevention of visual axis opacification after cataract surgery in children. (Chin J Ophthalmol, 2020, 56: 343-348).

Creation of Electron-Positron Pairs in Photon-Photon Collisions Driven by 10-PW Laser Pulses.

A novel approach is proposed to demonstrate the two-photon Breit-Wheeler process by using collimated and wide-bandwidth γ-ray pulses driven by 10-PW lasers. Theoretical calculations suggest that more than 3.2×10^{8} electron-positron pairs with a divergence angle of 7° can be created per shot, and the signal-to-noise ratio is higher than 10^{3}. The positron signal, which is roughly 100 times higher than the detection limit, can be measured by using the existing spectrometers. This approach, which could demonstrate the e^{-}e^{+} pair creation process from two photons, would provide important tests for two-photon physics and other fundamental physical theories.

[A multicenter study of the effectiveness and safety of Toric intraocular lens implantation].

Objective: To evaluate the effectiveness and safety of Proming(®)Toric intraocular lens (IOL) in adults with cataract combined with corneal regular astigmatism. Methods: Multicentre, randomized, open and positive parallel controlled clinical study. A total of 121 patients (121 eyes) who had cataract combined with corneal regular astigmatism and met the inclusion criteria were enrolled in 9 hospitals from May 2014 to May 2016. There were 45 males and 76 females and the median age was 71 (42-88) years old. A total of 121 patients (121 eyes) were randomly assigned to the study group and the control group through the Central Randomization System. Sixty patients (60 eyes) of the study group were implanted with Proming(®)Toric IOL (Model: AT1BH-AT6BH) from Eyebright Medical Technology (Beijing) Co., Ltd., and 61 patients (61 eyes) of the control group were implanted with AcrySof (®)IQ Toric IOL (Model: SN6AT2-SN6AT7) from Alcon Laboratories, Inc. The visual acuity, IOL axial position, slit lamp examination, residual astigmatism and contrast sensitivity were recorded at 1 day, 1 week, 1 month, 3 months, 6 months and 1 year postoperatively. Statistical analysis was performed using χ(2) test, independent sample t test, Mann-Whitney U test, Friedman repeated measured ANOVA on ranks and non-parametric 2-factor variance analysis. Results: A total of 118 patients completed 6 months of follow-up, including 59 from the study group and 59 from the control group. The difference between the two groups in terms of the percentage of best corrected distance visual acuity (BCDVA) reaching 20/40 was 1.69% [100% (59/59) vs. 98.31% (58/59) ], and the lower limit of the 95% CI (-1.60%) was greater than -10.00%. A total of 90 patients were followed up for 1 year, including 43 patients from study group and 47 patients from control group. At 1 year after operation, the percentages of the BCDVA up to 20/40 were 97.67%(42/43) in the study group and 97.87% (46/47) in the control group, and there was no significant difference between the two groups (χ(2)=0.00, P=0.95);the percentages of the uncorrected distance visual acuity (UCDVA) up to 20/40 were 81.40%(35/43) in the study group and 82.98%(39/47) in the control group, and there was no significant difference between the two groups (χ(2)=0.04, P=0.84). At 1 year follow-up, the difference of contrast sensitivity at 18.0 c/d under the bright light, dark light, bright glare and dark glare between the two groups was not statistically significant (U=468.50, P=0.17;U=528.00, P=0.28;U=465.50, P=0.19;U=629.00, P=0.39);the difference of residual astigmatism between the two groups was not statistically significant (U=798.50, P=0.08);the difference of IOL rotation degree between the two groups was not statistically significant (U=869.00, P=0.25). There were no severe inflammatory responses nor other complications associated with IOL in both groups at each follow-up point. Conclusion: The visual quality, astigmatism correction effect, rotation stability and safety of Proming(®)Toric IOL for the treatment of cataract combined with corneal regular astigmatism is equivalent to AcrySof(®) IQ Toric IOL. (Chin J Ophthalmol, 2018, 54: 349-356).

Probing of free and localized excitons and trions in atomically thin WSe2, WS2, MoSe2 and MoS2 in photoluminescence and reflectivity experiments.

We report on detailed temperature dependent (T = 7-295 K) optical spectroscopy studies of WSe2, WS2, MoSe2 and MoS2 monolayers exfoliated onto the same SiO2/Si substrate. In the high energy region of absorption type (reflectivity contrast-RC) and emission (photo-luminescence-PL) spectra of all the monolayers resonances related to the neutral and charged excitons (X and T) are detected in the entire measured temperature range. The optical amplitudes of excitons and trions strongly depend on the temperature and two dimensional carrier gas (2DCG) concentration. In the low energy PL spectra of WSe2 and WS2 we detect a group of lines (L) which dominates the spectra at low temperatures but rapidly quenches with the increase in the temperature. Interestingly, in the same energy range of the RC spectra recorded for WS2, we observe an additional line (L 0), which behaves in the same way as the L lines in the PL spectra. The optical amplitude of L 0 and T resonances in the RC spectra strongly increases with the growth of the 2DCG concentration. On the base of these observations we identify the L 0 resonance in the RC spectra as arising from the fine structure of the trion. We also propose that the line interpreted previously in PL spectra of WSe2 and WS2 as related to the biexciton emission is a superposition of the biexciton, trion and localized exciton emission. We find that with the temperature increase from 7-295 K the total PL intensity decreases moderately in WSe2 and WS2, strongly in MoS2 and dramatically in MoSe2.

Isolation and characterization of novel microsatellite markers in Mercenaria mercenaria.

Mercenaria mercenaria, also known as the hard clam, is widely distributed in the coastal waters of temperate and tropical areas in the Asian Pacific region. This species is widely popular in the international market, especially in the United States, Europe, and other Western countries, because of its high protein value, taste, and simple farming requirements. In this study, 17 novel microsatellite loci from the M. mercenaria genome were developed using the fast isolation by amplified fragment length polymorphism of sequences containing repeats protocol. Thirty-two wild individuals were used to evaluate the degree of polymorphism of these markers. Results indicated that there were 11 polymorphic loci and six monomorphic loci, and the number of alleles per locus and the polymorphism information content ranged from two to six and from 0.059 to 0.498, respectively. The observed and expected heterozygosity varied from 0.0625 to 0.5333 and 0.0615 to 0.4977, respectively. The Y1-4 locus deviated significantly from Hardy-Weinberg equilibrium (HWE) after Bonferroni correction was applied, while the other loci were in HWE. These loci will provide useful information for M. mercenaria population genetic studies.

Isolation and characterization of new microsatellite loci in Fenneropenaeus penicillatus.

Fenneropenaeus penicillatus is one of the major economic shrimp species in China. In this study, 14 novel microsatellite loci were developed using the fast isolation protocol with amplified fragment length polymorphism of sequences containing repeats (FIASCO). Polymorphisms were tested in 30 individuals from a single-wild population. The results showed that the number of alleles at each locus ranged from two to four, and the polymorphism information content varied from 0.314 to 0.692. The observed and expected heterozygosities ranged from 0.3343 to 0.6542 and from 0.3458 to 0.6657, respectively. Three loci deviated significantly from Hardy-Weinberg equilibrium after a Bonferroni correction was applied, while no deviations were detected in the other 11 loci. The new microsatellite loci identified in this study could be useful in future F. penicillatus population genetic, conservation research, population structure assessment, and linkage map construction studies.

Isolation and characterization of microsatellite markers in Atrina vexillum Born.

Atrina vexillum Born is an economically valuable species, widely distributed in the coastal waters of temperate and tropical areas of the Asia Pacific region. Twenty one novel microsatellite loci were identified in the genome of A. vexillum Born using the protocol for fast isolation by amplified fragment length polymorphism of sequence containing repeats. Thirty-two wild type individuals were used to evaluate the degree of polymorphism of these markers. We identified 13 polymorphic and 8 monomorphic loci with the number of alleles per locus and the polymorphism information content ranging from 2 to 5 and 0.141 to 0.664, respectively. The observed and expected heterozygosity varied from 0.1250 to 0.7000 and 0.1223 to 0.6216, respectively. Two loci deviated significantly from Hardy-Weinberg equilibrium (HWE) after Bonferroni correction, whereas the other loci were in HWE. These loci are expected to provide useful information for population genetic studies of A. vexillum Born.