Simultaneous separation and determination of seven biphenyl cyclooctene lignans in Schisandra chinensis and its preparations by micellar electrokinetic chromatography with dual organic solvent system.

INTRODUCTION: Gomisin is a natural dibenzo cyclooctene lignan, which is mainly derived from the family Magnoliaceae. It has anti-inflammatory, antioxidant, anti-tumor, anti-aging, and hypoglycemic effects. Gomisins play important roles as medicines, nutraceuticals, food additives, and cosmetics. OBJECTIVE: The objective of this study is to establish a micellar electrokinetic chromatography (MEKC) method for simultaneous separation and determination of seven biphenyl cyclooctene lignans (Gomisin D, E, G, H, J, N, and O) in Schisandra chinensis and its preparations. METHODS: The method was optimized by studying the effects of the main parameters on the separation. The method has been validated and successfully applied to the determination of seven Gomisins in S. chinensis and its preparations. RESULTS: In the separation system, the running buffer was composed of 20 mM Na2HPO4, 8.0 mM sodium dodecyl sulfate (SDS), 11% (v/v) methanol, and 6.0% (v/v) ethanol. A diode array detector was used with a detection wavelength of 230 nm, a separation voltage of 17 kV, and an operating temperature of 25°C. Under this condition, the seven analytes were separated at baseline within 20 min, and a good linear relationship was obtained with correlation coefficient ranging from 0.9919 to 0.9992. The limit of detection (LOD, S/N = 3) and the limit of quantification (LOQ, S/N = 10) ranged from 0.8 to 0.9 µg/mL and from 2.6 to 3.0 µg/mL, respectively. The recovery rate was between 99.1% and 102.5%. CONCLUSION: The experimental results indicated that this method is suitable for the separation and determination of seven Schisandra biphenyl cyclooctene lignan compounds in real samples. At the same time, it provides an effective reference for the quality control of S. chinensis and its preparations.

Ridge with no-tillage facilitates microbial N2 fixation associated with methane oxidation in rice soil.

Aerobic methane-oxidizing bacteria (MOB) play a crucial role in mitigating the greenhouse gas methane emission, particularly prevalent in flooded wetlands. The implementation of ridge with no-tillage practices within a rice-rape rotation system proves effective in overcoming the restrictive redox conditions associated with waterlogging. This approach enhances capillary water availability from furrows, especially during periods of low rainfall, thereby supporting plant growth on the ridges. However, the microbe-mediated accumulation of soil organic carbon and nitrogen remains insufficiently understood under this agricultural practice, particularly concerning methane oxidation, which holds ecological and agricultural significance in the rice fields. In this study, the ridge and ditch soils from a 28-year-old ridge with no-tillage rice field experiment were utilized for incubation with 13C-CH4 and 15NN2 to estimate the methane-oxidizing and N2-fixing potentials. Our findings reveal a significantly higher net production of fresh soil organic carbon in the ridge compared to the ditch soil during methane oxidation, with values of 626 and 543 µg 13C g-1 dry weight soil, respectively. Additionally, the fixed 15N exhibited a twofold increase in the ridge soil (14.1 µg 15N g-1 dry weight soil) compared to the ditch soil. Interestingly, the result of DNA-based stable isotope probing indicated no significant differences in active MOB and N2 fixers between ridge and ditch soils. Both Methylocystis-like type II and Methylosarcina/Methylomonas-like type I MOB catalyzed methane into organic biomass carbon pools. Soil N2-fixing activity was associated with the 15N-labeling of methane oxidizers and non-MOB, such as methanol oxidizers (Hyphomicrobium) and conventional N2 fixers (Burkholderia). Methane oxidation also fostered microbial interactions, as evidenced by co-occurrence patterns. These results underscore the dual role of microbial methane oxidation - not only as a recognized sink for the potent greenhouse gas methane but also as a source of soil organic carbon and bioavailable nitrogen. This emphasizes the pivotal role of microbial methane metabolism in contributing to soil carbon and nitrogen accumulation in ridge with no-tillage systems.

Stereopsis after bilateral implantation of Toric intraocular lenses in high myopic cataract patients with astigmatism.

Purpose: To evaluate near, intermediate, distance visual acuity and stereopsis after bilateral implantation of Toric intraocular lenses (IOLs) in high myopic patients with astigmatism. Methods: Bilateral Toric or non-Toric IOL implantation (n â€‹= â€‹40 eyes each) was performed on high myopic cataract eyes with astigmatism. Best-corrected distance visual acuity (BCDVA), uncorrected intermediate visual acuity (UCIVA), uncorrected near visual acuity (UCNVA), residual refractive astigmatism (RRA), and near, intermediate, and distance stereoacuity were measured postoperatively at 7 days, 1 month, and 3 months. Results: The three-month postoperative BCDVA, UCIVA, and UCNVA of the Toric group were 0.08 â€‹± â€‹0.07, 0.30 â€‹± â€‹0.11, and 0.23 â€‹± â€‹0.14 LogMAR. All improved over the preoperative assessments (P â€‹< â€‹0.05). The RRA, UCIVA, and UCNVA were significantly better in the Toric group than the non-Toric group at all follow-up examinations (all P â€‹< â€‹0.05). At 3 months, the median near and intermediate stereoacuity of the Toric group were 100 (range 40 - 400) and 120 (range 50 - 400) arcsec, which were better than the non-Toric group (both P â€‹< â€‹0.05). Fine near stereopsis ≥100 arcsec was present in 65% of the Toric patients, and 50% had good intermediate stereopsis of ≥100 arcsec. However among non-Toric patients, only 15% and 5% achieved fine near and intermediate stereopsis. The postoperative BCDVA and best-corrected distance stereoacuity were similar in the two groups (P â€‹> â€‹0.05). Conclusions: In bilateral high myopic cataract patients with astigmatism, Toric IOLs not only improved UCIVA, UCNVA, and RRA, but also enhanced near and intermediate stereopsis acuity.

Accuracy of the FY-L formula in calculating intraocular lens power after small-incision lenticule extraction.

Purpose: The study aimed to assess the accuracy of the FY-L formula in calculating intraocular lens (IOL) power after small-incision lenticule extraction (SMILE). Methods: For the post-SMILE IOL calculation of the same eye, the IOL power targeting the pre-SMILE eyes' lowest myopic refractive error was used. The FY-L formula, the Emmetropia Verifying Optical Formula (EVO-L), the Barrett True-K no history, and the Shammas-L, respectively, were used to calculate the predicted refractive error of target IOL power. A comparison was made between the change in spherical equivalent induced by SMILE (SMILE-Dif) and the variance between IOL-Dif (IOL-Induced Refractive Error) before and after SMILE. The prediction error (PE) was defined as SMILE-Dif minus IOL-Dif. The proportion of eyes with PEs within ±0.25 D, ±0.50 D, ±0.75 D, and ±1.00 D, the numerical and absolute prediction errors (PEs and AEs), and the median absolute error (MedAE) were compared. Results: In total, 80 eyes from 42 patients who underwent SMILE were included in the study. The FY-L formula generated the sample's lowest mean PE (0.06 ± 0.76 D), MAE (0.58 ± 0.50 D), and MedAE (0.47 D), respectively. The PEs in ±0.25 D, ±0.50 D, ±0.75 D, and ±1.00 D comprised 28.8%, 46.3%, 70.0%, and 87.5%, respectively, for the FY-L formula. Compared to other formulas, the FY-L formula produced the highest value with PEs for the percentage of eyes in ±0.50 D, ±0.75 D, and ±1.00 D. Conclusion: This study demonstrates that the FY-L formula provides satisfactory outcomes in estimating the IOL power in the eyes after SMILE.

Methanogenic and methanotrophic communities determine lower CH4 fluxes in a subtropical paddy field under long-term elevated CO2.

Clarifying the effects of elevated CO2 concentration (e[CO2]) on CH4 emissions from paddy fields and its mechanisms is a crucial part of the research on agricultural systems in response to global climate change. However, the response of CH4 fluxes from rice fields to long-term e[CO2] (e[CO2] duration >10 years) and its microbial mechanism is still lacking. In this study, we used a long-term free-air CO2 enrichment experiment to examine the relationship between CH4 fluxes and the methanogenic and methanotrophic consortia under long- and short-term e[CO2]. We demonstrated that contrary to the effect of short-term e[CO2], long-term e[CO2] decreased CH4 fluxes. This may be associated with the reduction of methanogenic abundance and the increase of methanotrophic abundance under long-term e[CO2]. In addition, long-term e[CO2] also changed the community structure and composition of methanogens and methanotrophs compared with short-term e[CO2]. Partial least squares path modeling analysis showed that long-term e[CO2] also could affect the abundance and composition of methanogens and methanotrophs indirectly by influencing soil physical and chemical properties, thereby ultimately altering CH4 fluxes in paddy soils. These findings suggest that current estimates of short-term e[CO2]-induced CH4 fluxes from paddy fields may be overestimated. Therefore, a comprehensive assessment of climate­carbon cycle feedbacks may need to consider the microbial regulation of CH4 production and oxidation processes in paddy ecosystems under long-term e[CO2].

A spiral slotted transducer with high longitudinal-torsional conversion rate.

The longitudinal-torsional (L-T) composite piezoelectric transducer has wide applications in material processing, welding, and other fields due to its exceptional machining efficiency. This study introduces a spiral slotted L-T transducer, which is designed to achieve a high L-T conversion rate at low operating frequency. The equivalent spring concept is employed to derive the equivalent circuit of the L-T transducer, which provides a convenient study for the frequency characteristics of the transducer. A finite element model is developed to analyze the performance of the transducer and investigate the effect of the spiral slot parameters on the resonance frequency, amplitude, and the L-T conversion rate of it. Two prototype transducers are constructed and measured experimentally. Theoretical computation results, finite element simulation results, and experimental results are compared to each other. The comparison results demonstrate that the proposed computation model provides accurate prediction of the L-T coupling resonance frequency of the transducer. By adjusting the spiral slot parameters of the transducer, a higher L-T conversion rate can be achieved, which may have more applications in practical engineering.

Evaluation of new approach to enhance visualization performance in cataract surgery: 3D visualization system with coaxial illumination.

PURPOSE: To evaluate the visualization performance of different approaches, including the 3D visualization system with coaxial illumination and the 3D system or microscope with standard illumination. SETTING: Fuzhou Eye Hospital, Fuzhou City, China. DESIGN: Cross-sectional study. METHODS: This 2-part performance assessment for visualization composed of an objective analysis using surgical video images and a subjective survey collecting feedback from surgeons. Data of each eye were obtained with 3 approaches: standard operating microscope with standard illumination (SOM-S), 3D visualization system with standard illumination (3D-S), and 3D visualization system with coaxial illumination (3D-C). RESULTS: 112 eyes (107 cases) and 6 cataract surgeons were involved. The red reflex value was markedly greater in the 3D-C approach compared with other 2 approaches ( P < .001). Compared with the SOM-S approach, the red reflex increased by 55%, 57%, and 53% in the 3D-C approach, corresponding to nuclear grades of II, III, and IV, respectively. In the questionnaire survey, red reflex scores were consistently significantly higher in the 3D-C approach than those in the others ( P < .001). Depth of field was enhanced in both 3D approaches compared with the SOM-S approach ( P < .05). The only minor advantage of the SOM system over the 3D-C approach was in the surrounding field clarity score, and the difference was not statistically significant ( P = 1.000). CONCLUSIONS: The 3D-C approach significantly increased the red reflex in both objective and subjective assessments. Surgeon responses also showed a superior performance for the 3D-C approach.

Modelling methane emissions and grain yields for a double-rice system in Southern China with DAYCENT and DNDC models.

Methane (CH4) is an important greenhouse gas that contributes to climate change and one of its major sources is rice cultivation. The main aim of this paper was to compare two well-established biogeochemical models, namely Daily Century (DAYCENT) and DeNitrification-DeComposition (DNDC) for estimating CH4 emissions and grain yields for a double-rice cropping system with tillage practice and/or stubble incorporation in the winter fallow season in Southern China. Both models were calibrated and validated using field measured data from November 2008 to November 2014. The calibrated models performed effectively in estimating the daily CH4 emission pattern (correlation coefficient, r = 0.58-0.63, p < 0.001), but model efficiency (EF) values were higher in stubble incorporation treatments, with and without winter tillage (treatments S and WS) (EF = 0.22-0.28) than that in winter tillage without stubble incorporation treatment (W) (EF = -0.06-0.08). We recommend that algorithms for the impacts of tillage practice on CH4 emission should be improved for both models. DAYCENT and DNDC also estimated rice yields for all treatments without a significant bias. Our results showed that tillage practice in the winter fallow season (treatments WS and W) significantly decreased annual CH4 emissions, by 13-37 % (p < 0.05) for measured values, 15-20 % (p < 0.05) for DAYCENT-simulated values, and 12-32 % (p < 0.05) for DNDC-simulated values, respectively, compared to no-till practice (treatments S), but had no significant impact on grain yields.

The impact of preloaded intraocular lens implantation system (TECNIS iTec®) in routine cataract surgery in China: a time-motion analysis.

OBJECTIVE: To evaluate the impact on surgical efficiency and labor time cost of preloaded intraocular lens (IOL) implantation system compared with manual IOL implantation system in age-related cataract surgery in China. METHODS: This study was an observational, multicenter, prospective time-motion analysis. IOL preparation time, operation time, cleaning time, number and cost of cataract surgeries in eight participating hospitals were collected. The linear mixed model was used to explore factors associated with the difference in operation time between the preloaded IOL implantation system and the manual IOL implantation system. A time-motion model was constructed to convert the operation time cost saved by using preloaded IOL into economic benefits from hospital and social perspective, respectively. RESULTS: There were 2,591 cases included in the study (preloaded IOL: 1,591 cases; manual IOL: 1,000 cases). The preloaded IOL implantation system was significant time-saving in both preparation time and operation time compared to the manual IOL implantation system (25.48s vs. 47.04s, P < 0.001 and 353.84s vs. 367.46s, P = 0.004, respectively). An average total of 35.18s can be saved by using preloaded IOL per procedure. The results of linear mixed model showed that the type of IOL was the main factor leading to the difference in preparation time between preloaded IOL and manual IOL implantation system. By switching from manual IOL to preloaded IOL, the model projected additional 392 surgeries can be performed each year and an increase in revenue of $565,282 per hospital, a 9% increase from hospital perspective. And the annual productivity loss saved by using preloaded IOL was $3,006 in eight hospitals from perspective of society. CONCLUSION: Compared with manual IOL implantation system, the preloaded IOL implantation system reduces lens preparation time and operation time, which increases potential surgical volume and revenue, and reduces the loss of work productivity. This study provides real-world evidence to support the advantages of the preloaded IOL implantation system in improving efficiency of ophthalmic surgery in China.

Application of three-dimensional visualization technology in phacoemulsification benefits the dry eye symptoms of patients after cataract surgery.

Purpose: To investigate the effects of the three-dimension visualization system on dry eye in patients after cataract phacoemulsification. Methods: Seventy-one patients (104 eyes) were enrolled in this study and assigned to the conventional microscopic group (CM group) or three-dimension group (3D group). Ocular Surface Disease Index, The Schirmer I test (SIt), lipid layer thickness (LLT), noninvasive tear breakup time (NIBUT) and other factors associated with dry eye were recorded before and 1 week and 1 month after surgery. The operation time and intraoperative light intensity (ILI) were also recorded. Results: The ILI in the 3D group was significantly lower than that in the CM group (33% vs. 60%, p < 0.01). There was an interaction (group and time) effect for first NIBUT (NIBUT-F), average NIBUT (NIBUT-Ave), tear meniscus height (TMH) and the score of eye redness (Pinteraction < 0.05). The main effects of group on SIt, LLT, NIBUT-F, NIBUT-Ave and the score of eye redness were significant (Pgroup < 0.05). In the CM group, SIt, LLT, NIBUT-F, NIBUT-Ave, TMH were lower than those of the 3D group, the score of eye redness was higher than that of the 3D group at 1 week and 1 month after surgery (all p < 0.05). The changes in NIBUT-F and NIBUT-Ave between before surgery and 1 week after surgery showed negative correlations with ILI (p < 0.01). Conclusion: Compared with microscopic surgery, the 3D visualization system can provide better tear film stability for patients after cataract surgery.

Efficient and Bright Deep-Red Light-Emitting Diodes based on a Lateral 0D/3D Perovskite Heterostructure.

Bright and efficient deep-red light-emitting diodes (LEDs) are important for applications in medical therapy and biological imaging due to the high penetration of deep-red photons into human tissues. Metal-halide perovskites have potential to achieve bright and efficient electroluminescence due to their favorable optoelectronic properties. However, efficient and bright perovskite-based deep-red LEDs have not been achieved yet, due to either Auger recombination in low-dimensional perovskites or trap-assisted nonradiative recombination in 3D perovskites. Here, a lateral Cs4 PbI6 /FAx Cs1- x PbI3 (0D/3D) heterostructure that can enable efficient deep-red perovskite LEDs at very high brightness is demonstrated. The Cs4 PbI6 can facilitate the growth of low-defect FAx Cs1- x PbI3 , and act as low-refractive-index grids, which can simultaneously reduce nonradiative recombination and enhance light extraction. This device reaches a peak external quantum efficiency of 21.0% at a photon flux of 1.75 × 1021 m-2 s-1 , which is almost two orders of magnitude higher than that of reported high-efficiency deep-red perovskite LEDs. Theses LEDs are suitable for pulse oximeters, showing an error <2% of blood oxygen saturation compared with commercial oximeters.

Visual outcomes and subjective experience with three intraocular lenses based presbyopia correcting strategies in cataract patients.

To compare the visual outcomes and subjective experience of three intraocular lenses (IOL) implant strategies. Retrospective comparative study. This study comprised patients who underwent phacoemulsification and bilateral implantation of extended depth of focus (EDOF) IOL (ZXR00; EDOF group), blended implantation of EDOF and bifocal IOL (ZXR00/ZLB00; blended group), and bilateral implantation of trifocal IOL (AT LISA tri 839MP; trifocal group). The outcomes included visual acuity (VA), visual defocus curve, contrast sensitivity, visual quality, quality of life, spectacle independence, and patient satisfaction. Follow-up was performed 3 months after the surgery. This study included 114 eyes of 57 patients (20 in EDOF group; 16 in blended group; 21 in trifocal group). Patients in the three groups had high quality of life, patient satisfaction, and good contrast sensitivity. The EDOF group had the worst near VA, but the visual quality was the best. The blended group had good VA and slight photic disturbance. The trifocal group obtained the best whole range of VA, but the photic disturbance was significantly severe than the EDOF group. Both the blended and trifocal groups achieved high spectacle independence, but some patients in the EDOF group need spectacle when dealing with close-range tasks.

Stereopsis and visual acuity: Bilateral trifocal versus blended extended depth of focus and diffractive bifocal intraocular lenses.

Purpose: To compare stereopsis and visual acuity (VA) between bilateral implantation of trifocal intraocular lenses (IOL) and blended implantation of an extended depth of focus (EDOF) IOL with a bifocal IOL. Methods: This is a non-randomized, prospective comparative study included 74 eyes of 37 patients who underwent phacoemulsification and bilateral implantation of AT LISA tri 839MP IOL (bilateral group; 21 patients) or blended implantation of Tecnis Symfony ZXR00 and Tecnis ZLB00 IOL (blended group; 16 patients). The primary outcomes were stereoacuity and binocular VA. The secondary outcomes were visual defocus curve, quality of life, and patient satisfaction. Follow-up was performed 3 months after the surgery. Results: The mean near stereoacuity was 49.76 ± 22.67 and 120.63 ± 90.94 seconds of arc (arcsec) in the bilateral and blended groups, respectively (P < 0.001). Near stereoacuity was positively correlated with VA difference of two eyes (r = 0.896, P < 0.001). The mean binocular uncorrected visual acuity at 40 cm, 80 cm, 5 m, and corrected distance visual acuity at 5 m of the bilateral and blended groups was not statistically significant different. The bilateral group had better VA at a vergence from -2.5 to -4.0 D. Both groups obtained high quality of life and patient satisfaction scores. Conclusion: The bilateral and blended groups achieved good binocular VA, quality of life, and high patient satisfaction. However, the near stereoacuity of the blended group was worse.

Winter drainage and film mulching cultivation mitigated CH4 emission by regulating the function and structure of methanogenic archaeal and fermenting bacterial communities in paddy soil.

Winter flooding of harvested rice fields is a typical cropping system in mountainous areas, which emits considerable amounts of CH4. Plastic film mulching cultivation is recognized as an important rice cultivation practice in paddy field for water-saving irrigation. However, the effects of these managements on CH4 emissions in paddy soil and the underlying microbial mechanism are unclear. A field experiment was carried out with the application of winter drainage followed by traditional rice cultivation (WD), winter drainage followed by plastic film mulching cultivation (MC), as well as winter flooding followed by traditional rice cultivation (WF) as control in hilly paddy fields. We investigated the CH4 emissions, functional (CH4 production rate, 13C isotope) and structural (abundance, structure) responses of soil methanogenic archaeal and fermenting bacterial communities during rice season. Shifting the fields from WF into WD and MC substantially mitigated CH4 emissions by 62.3% and 59.2%, respectively, paralleled with the enhancement of soil Eh and the reductions of soil DOC content. Compared with WF, WD and MC both significantly decreased CH4 production rates and the copy numbers of mcrA gene. Moreover, an increasing contribution of hydrogenotrophic methanogenesis (from 30.7% to 50.0%) to total CH4 production was observed during the conversion from WF to MC under an anaerobic incubation, paralleled with the decreased acetate content and increased δ13C values of acetate-methyl and total acetate. The communities of methanogenic archaea and fermenting bacteria strongly responded to the shift from WF to WD, while MC only showed significant effects on the methanogenic archaeal communities. Compared with WF, WD and MC significantly increased the relative abundance of Methanothrix, Methanosarcina and Methanocella, while those of Methanoregula, Massilia and Geobacter were decreased. The co-occurrence networks showed that WD and MC induced the loss of mixed methanogenic fermentation modules, indicating the decrease in functional biodiversity and redundancy of fermenting bacterial and methanogenic archaeal communities.The findings suggest that WD and MC approach mitigate CH4 emission by regulating the function and structure of methanogenic archaeal and fermenting bacterial communities in paddy soil, which represent the effective management strategies considering the water availability and CH4 mitigation in paddy-field agriculture.

Simultaneous separation and determination of six furanocoumarins in Radix Angelicae dahuricae by CZE with dual CDs system.

A novel, simple and efficient capillary electrophoresis method was developed to simultaneous determination of six furanocoumarins (psoralen, isopsoralen, imperatorin, isoimperatorin, phellopterin, and cnidilin). The separation buffer consisted of 30 mM boric acid, 12 mM sulfobutylether-ß-cyclodextrin and 1.5 mM 2-hydroxypropyl-ß-cyclodextrin (pH 7.8); the voltage was 20 kV, the temperature was 25 °C and the detection wavelength was at 246 nm with a diode array detector (DAD). Under the above conditions, the analytes could be separated with high resolution in less than 7 min. This method was used to simultaneously determine the content of psoralen, imperatorin, isoimperatorin and phellopterin in Angelica Dahurica Radix. And good linearities were obtained with correlation coefficients from 0.9992 to 0.9999. The limits of detection (LOD, S/N = 3) and the limits of quantitation (LOQ, S/N = 10) ranged from 0.6 to 3.0 µg/mL and from 2.1 to 9.9 µg/mL, respectively. The recoveries ranged between 98.8% and 101.8%. The results indicated the method can achieve baseline separation and quantitative analysis of furanocoumarins in Chinese herbal medicines and formulations.

Acoustic radiation force of a sphere with a hemispherically split boundary condition in a plane wave.

In this paper, an analytical expression of the acoustic radiation force (ARF) for a spherical particle with a hemispherically split impedance boundary in a plane wave is deduced. Numerical calculations are carried out by considering the effect of the magnitude and phase of the acoustic impedance on the ARF. Computation results show that the increase in the magnitude of the acoustic impedance results in an overall decrease in the ARF, whereas the phase of the acoustic impedance results in a decrease in the ARF in the low frequency region. As the frequency increases, the positive phase angle leads to a decrease in the ARF, and the negative phase angle causes the ARF to increase rapidly. For a hemispherically split impedance sphere, the values of the ARF range from those of the rigid sphere and uniform impedance sphere. The finite-element models for the calculation of the ARF of a hemispherically split impedance boundary sphere are established and the correctness of the analytical theory is proved by numerical comparison. This work is expected to contribute theoretical support to the acoustic manipulation of particles with a nonuniform hemispherically split structure.

[Methane Production Potential and Methanogenic Pathways in Paddy Soils Under Different Rice-based Cropping Systems].

Differences inmethane (CH4) production potential in paddy soils under different rice-based cropping systems and especially in the methanogenic pathways (mainly acetate fermentation and CO2/H2 reduction) remain unclear. Anaerobic incubations of soil with or without fluoromethane (CH3F) inhibitor (2% and 0%) were conducted. With the soils from three typical paddy ecosystems (rice-wheat rotation, RW; rice-fallow, RF; double-rice, DR) in China, the cumulative concentration of CH4 production, CH4 production potential, dissolved organic carbon (DOC) content, and acetic acid content were determined. Meanwhile, the relative contribution of acetate-dependent methanogenesis (fac) was quantified using the stable carbon isotope method. The results showed that the CH4 production potential was 7.18 µg·(g·d)-1 in RF, which was significantly lower than that in RW[10.33 µg·(g·d)-1]and DR[13.42 µg·(g·d)-1] (P<0.05). Correlation analysis showed that CH4 production potential was significantly negatively correlated with soil cation exchange capacity and pH (P<0.01); the addition of CH3F significantly inhibited CH4 production (P<0.05). The content of DOC and acetic acid in DR were 255 mg·kg-1 and 7.34 mg·kg-1, respectively, which were 17%-51% and 22%-23% higher than those in RW and RF, respectively. The δ13CH4 and δ13CO2 values were affected greatly by different rice-based cropping systems, and the highest δ13CH4 value was -43.89‰ in RF, which was more positive than that of RW and DR by 11.06‰ and 8.33‰, respectively (P<0.05). By contrast, the lowest value of δ13CO2 was observed in RF, which was more negative than that of RW (7.63‰) and DR (5.14‰) (P<0.05). The α(CO2/CH4) values of RW and RF were 1.057 and 1.058, respectively, which were significantly lower than 1.062 in DR (P<0.05). The fac values of RF ranged from 84% to 98%, being 34%-38% and 20%-23% higher than those of RW and DR, respectively (P<0.05).

Simultaneous separation and determination of five chlorogenic acid isomers in Honeysuckle by capillary electrophoresis using self-synthesized ionic liquid [N-methylimidazole-ß-cyclodextrin] [bromide] as separation selector.

A simple, comprehensive, and efficient capillary electrophoresis method using a self-synthesized ionic liquid [N-methylimidazole-ß-cyclodextrin] [bromide] as a separation selector was developed for the simultaneous separation and determination of five chlorogenic acid isomers (chlorogenic acid, cryptochlorogenic acid, neochlorogenic acid, isochlorogenic acid A, isochlorogenic acid B). After optimization of separation conditions, the electrolyte solution was 50 mM ammonium acetate buffer containing 0.7% (w/w) ionic liquid [N-methylimidazole-ß-cyclodextrin] [bromide] (pH 4.8), 15 kV of the electric field was applied at 25°C, and the detection wavelength was at 237 nm. Under the optimal separation conditions, good linearities were obtained with linear correlation coefficients of the five analytes of 0.9994-0.9998, and the limits of detection and the limits of quantification were 0.6-2.8 and 2.2-9.5 µg/ml. Excellent accuracy and precision were obtained for the five analytes. The intraday and interday precision of standards ranged from 0.5 to 1.3% and from 1.2 to 1.9%. The intraday and interday precision of samples ranged from 1.0 to 1.9% and from 1.2 to 2.6%. The sample recovery rates were between 98.0 and 101.8%. This method was successfully applied for the analysis of five components in Honeysuckle Chinese medicinal preparations. The mechanisms involved in the separation of five analytes by [N-methylimidazole-ß-cyclodextrin] [bromide] were discussed.

Intraocular lens power calculation after two different successive corneal refractive surgeries.

Purpose: To report two challenging intraocular lens power calculation cases with patients each underwent different successive corneal refractive surgeries, respectively. Observations: Biometry data, including the Back to Front corneal radii ratio (B/F ratio), were collected by Lenstar, IOL Master, and Pentacam AXL for Case 1 (received radial keratotomy (RK) and photorefractive keratectomy (PRK)) and Case 2 (received RK and laser-assisted in situ keratomileusis (LASIK)). The IOL power calculation was determined by several methods, including Shammas, Haigis-L, and Barrett True-K, which are available in the American Society of Cataract and Refractive Surgery online calculator and Pentacam AXL. The Barrett True-K (no history, post-RK) was more accurate in Case 1 (increased B/F ratio), whereas the Shammas, Haigis-L, and Barrett True-K (no history, post-LASIK/PRK) were more accurate in Case 2 (decreased B/F ratio). Conclusion and importance: The B/F ratio may be a factor to be considered when selecting the IOL power calculation formula for patients who undergo two different corneal refractive surgeries. The further study focusing on this issue should be performed to clarify the results in the future.