Coherence-controlled chaotic soliton bunch.

Controlling the coherence of chaotic soliton bunch holds the promise to explore novel light-matter interactions and manipulate dynamic events such as rogue waves. However, the coherence control of chaotic soliton bunch remains challenging, as there is a lack of dynamic equilibrium mechanism for stochastic soliton interactions. Here, we develop a strategy to effectively control the coherence of chaotic soliton bunch in a laser. We show that by introducing a lumped fourth-order-dispersion (FOD), the soliton oscillating tails can be formed and generate the potential barriers among the chaotic solitons. The repulsive force between neighboring solitons enabled by the potential barriers gives rise to an alleviation of the soliton fusion/annihilation from stochastic interactions, endowing the capability to control the coherence in chaotic soliton bunch. We envision that this result provides a promising test-bed for a variety of dynamical complexity science and brings new insights into the nonlinear behavior of chaotic laser sources.

The High Resistance Loop (H-Loop) Technique for Arthroscopic Repair of Subscapularis.

The subscapularis tendon is more challenging and riskier to repair than the posterior upper rotator cuff. The knotless anchor suture in subscapularis repair simplified the repair process and had an excellent postoperative effect. We describe a new knotless anchor stitching method, the H-Loop technique. The simplicity and efficiency of the technique make it particularly suitable for small subscapular tendon tears.

Alternative approaches to modeling heterogeneity to analyze injury severity sustained by motorcyclists in two-vehicle crashes.

The presence of unobserved factors in the motorcycle involved two-vehicle crashes (MV) data could lead to heterogenous associations between observed factors and injury severity sustained by motorcyclists. Capturing such heterogeneities necessitates distinct methodological approaches, of which random and scale heterogeneity models are paramount. Herein, we undertake an empirical evaluation of random and scale heterogeneity models, exploring their efficacy in delineating the influence of external determinants on the degree of injury severity in crashes. Within the effects of scale heterogeneity, this study delves into two dominant models: the scaled multinomial logit model (S-MNL) and its generalized counterpart, the G-MNL, which encompasses both the S-MNL and the random parameters multinomial logit model (RPL). While the random heterogeneity domain is represented by the random parameters multinomial logit and an upgraded variant - the random parameters multinomial logit model with heterogeneity in means and variances (RPLHMV). Motorcycle involved two-vehicle crashes data were extracted from the UK STATS19 dataset from 2016 to 2020. Likelihood ratio tests are computed to assess the temporal variability of the significant factors. The test result demonstrates the temporal variations over a five-year study period. Some very important differences started to show up across the years based on the model estimation results: that the RPLHMV model statistically outperforms the G-MNL model in the 2016, 2018, and 2019 models, while the S-MNL model is statistically superior in the 2017 and 2020 years. These important findings suggest that the origin of heterogeneity in explaining factor weights can be captured by scale effects, not just random heterogeneity. In addition, the model results further show that motorcyclists' injury severities are significantly affected by motorcycle-related characteristics; there is the added factor of external influences, such as non-motorcycle drivers (males, young drivers, and elderly drivers) and vehicles (the moving status, age, and types of vehicles) that collide with motorcycles. The results of this paper are anticipated to help policymakers develop effective strategies to mitigate motorcycle involved two-vehicle crashes by implementing appropriate measures.

Three-Dimensional Magnetic Resonance Imaging Fast Field Echo Resembling a Computed Tomography Using Restricted Echo-Spacing Sequence Is Equivalent to 3-Dimensional Computed Tomography in Quantifying Bone Loss and Measuring Shoulder Morphology in Patients With Shoulder Dislocation.

PURPOSE: To evaluate the equivalence of 3-dimensional (3D) magnetic resonance imaging (MRI) (FRACTURE [Fast field echo Resembling A CT Using Restricted Echo-spacing]) and 3D computed tomography (CT) in quantifying bone loss in patients with shoulder dislocation and measuring morphologic parameters of the shoulder. METHODS: From July 2022 to June 2023, patients with anterior shoulder dislocation who were aged 18 years or older and underwent both MRI and CT within 1 week were included in the study. The MRI protocol included an additional FRACTURE sequence. Three-dimensional reconstructions of MRI (FRACTURE) and CT were completed by 2 independent observers using Mimics software (version 21.0) through simple threshold-based segmentation. For bone defect cases, 2 independent observers evaluated glenoid defect, percentage of glenoid defect, glenoid track, Hill-Sachs interval, and on-track/off-track. For all cases, glenoid width, glenoid height, humeral head-fitting sphere radius, critical shoulder angle, glenoid version, vault depth, and post-processing time were assessed. The paired t test was used to assess the differences between 3D CT and 3D MRI (FRACTURE). Bland-Altman plots were constructed to evaluate the consistency between 3D CT and 3D MRI (FRACTURE). Interobserver and intraobserver agreement was evaluated with the interclass correlation coefficient. The paired χ2 test and Cohen κ statistic were used for binary variables (on-track/off-track). RESULTS: A total of 56 patients (16 with bipolar bone defect, 5 with only Hill-Sachs lesion, and 35 without bone defect) were ultimately enrolled in the study. The measurements of 21 bone defect cases showed no statistically significant differences between 3D CT and 3D MRI: glenoid defect, 4.05 ± 1.44 mm with 3D CT versus 4.16 ± 1.39 mm with 3D MRI (P = .208); percentage of glenoid defect, 16.21% ± 5.95% versus 16.61% ± 5.66% (P = .199); glenoid track, 18.02 ± 2.97 mm versus 18.08 ± 2.98 mm (P = .659); and Hill-Sachs interval, 14.29 ± 1.93 mm versus 14.35 ± 2.07 mm (P = .668). No significant difference was found between 3D CT and 3D MRI in the diagnosis of on-track/off-track (P > .999), and diagnostic agreement was perfect (κ = 1.00, P < .001). There were no statistically significant differences between the 2 examination methods in the measurements of all 56 cases, except that the post-processing time of 3D MRI was significantly longer than that of 3D CT: glenoid height, 34.56 ± 1.98 mm with 3D CT versus 34.67 ± 2.01 mm with 3D MRI (P = .139); glenoid width, 25.32 ± 1.48 mm versus 25.45 ± 1.47 mm (P = .113); humeral head-fitting sphere radius, 22.91 ± 1.70 mm versus 23.00 ± 1.76 mm (P = .211); critical shoulder angle, 33.49° ± 2.55° versus 33.57° ± 2.51° (P = .328); glenoid version, -3.25° ± 2.57° versus -3.18° ± 2.57° (P = .322); vault depth, 37.43 ± 1.68 mm versus 37.58 ± 1.75 mm (P = .164); and post-processing time, 89.66 ± 10.20 seconds versus 360.93 ± 26.76 seconds (P < .001). For all assessments, the Bland-Altman plots showed excellent consistency between the 2 examination methods, and the interclass correlation coefficients revealed excellent interobserver and intraobserver agreement. CONCLUSIONS: Three-dimensional MRI (FRACTURE) is equivalent to 3D CT in quantifying bone loss in patients with shoulder dislocation and measuring shoulder morphologic parameters. LEVEL OF EVIDENCE: Level II, development of diagnostic criteria (consecutive patients with consistently applied reference standard and blinding).

Elaborating the Occurrence and Distribution of Per- and Polyfluoroalkyl Substances in Rivers and Sediment around a Typical Aging Landfill in China.

Per- and polyfluoroalkyl substances (PFASs) are bioaccumulative and widely distributed persistent organic pollutants (POPs). Understanding the distribution of and ecological risks posed by PFASs is critical, particularly for PFAS emissions and accumulation from a common urban pollution source. The transformation characteristics and ecological risks of PFASs from a typical aging municipal landfill leachate were systematically monitored and assessed over five years in this study. The results showed that the total PFAS concentrations (ΣPFASs) in the rivers were between 26.4 and 464.3 ng/L, whereas in sediment, ΣPFASs ranged from 9.5 to 58.5 ng/g (w/w). The presence of perfluorooctanoic acid (PFOA) was the most prominent PFAS in both water (39.4-152.3 ng/L) and sediment (1.1-56.1 ng/g). In a five-year monitoring study, the concentration of PFASs in the aging landfill decreased by 23.3%, with higher mean concentrations observed during summer (307.6 ng/L) compared to winter (250.4 ng/L). As for the pollution distribution, the suspended particulate matter-water partition coefficient (log Kd) of carboxylic acid (PFCAs) and perfluoroalkane sulfonic acids (PFSAs) ranged from 1.53 to 2.65, and from 1.77 to 2.82, respectively. PFSAs and long-chain PFCAs exhibited a greater propensity for sediment association compared to short-chain PFCAs. An ecological risk assessment of four typical PFASs, PFOA, perfluorooctane sulfonate (PFOS), perfluorobutanoic acid (PFBA), and perfluorobutane sulfonic acid (PFBS), utilizing the hazard quotient method revealed that the rivers surrounding the typical aging landfill exhibited a low contamination risk for PFOA, while no ecological risks were associated with the other three FPASs. This study contributes to an enhanced comprehension of the occurrence, distribution, and risk of PFASs in the rivers in rivers and sediment surrounding a typical aging landfill site in China, thereby providing crucial reference information for ensuring water quality safety.

Bivariate joint analysis of injury severity of drivers in truck-car crashes accommodating multilayer unobserved heterogeneity.

Truck-involved crashes, especially truck-car crashes, are associated with serious and even fatal injuries, thus necessitating an in-depth analysis. Prior research focused solely on examining the injury severity of truck drivers or developed separate performance models for truck and car drivers. However, the severity of injuries to both drivers in the same truck-car crash may be interrelated, and influencing factors of injury severities sustained by the two parties may differ. To address these concerns, a random parameter bivariate probit model with heterogeneity in means (RPBPHM) is applied to examine factors affecting the injury severity of both drivers in the same truck-car crash and how these factors change over the years. Using truck-car crash data from 2017 to 2019 in the UK, the dependent variable is defined as slight injury and serious injury or fatality. Factors such as driver, vehicle, road, and environmental characteristics are statistically analyzed in this study. According to the findings, the RPBPHM model demonstrated a remarkable statistical fit, and a positive correlation was observed between the two drivers' injury severity in truck-car crashes. More importantly, the effects of the explanatory factors showing relatively temporal stability vary across different types of vehicle crashes. For example, car driver improper actions and lane changing by trucks, have a significant interactive effect on the severity of injuries sustained by drivers involved collisions between trucks and cars. Male truck drivers, young truck drivers, older truck drivers, and truck drivers' improper actions, elevate the estimated odds of only truck drivers; while older car and unsignalized crossing increase the possibility of injury severity of only car drivers. Finally, due to shared unobserved crash-specific factors, the 30-mph speed limit, dark no lights, and head-on collision, significantly affect the severity of injuries sustained by drivers involved in collisions between trucks and cars. The modeling approach provides a novel framework for jointly analyzing truck-involved crash injury severities. The findings will help policymakers take the necessary actions to reduce truck-car crashes by implementing appropriate and accurate safety countermeasures.

Exploring weather-related factors affecting the delay caused by traffic incidents: Mitigating the negative effect of traffic incidents.

BACKGROUND: Existing studies mainly focus on the relationship between real-time weather and traffic crash injury severity, while few scholars have investigated the operation risk levels caused by traffic incidents. Identifying weather-related factors that affect the incident-induced delay is helpful for estimating the delay levels when an incident occurs. Accordingly, the present study profoundly explores the relationship between weather conditions and traffic delays caused by traffic incidents. METHODS: The traffic incident and weather datasets from January 1 to December 31, 2020, in New York State are used. To that end, the hazard-based duration and multinomial logit modeling frameworks are employed to determine the effect of weather conditions on the duration of traffic delay and the delay severity, respectively. More importantly, to account for multiple layers of unobserved heterogeneity, a random parameter with heterogeneity in means approach is introduced into the above two models. RESULTS: (1) The strong breeze (wind speed over 8 m/s) and low visibility (visibility under 5 km) significantly affect the duration of delay. (2) Hot day (between 20 and 30 °C) has a 344.03 % greater probability of minor delay. A strong breeze has a higher probability of severe delay. The low visibility is found to increase the estimated odds of moderate delay and severe delay by 51.15 % and 13.39 %, respectively. In comparison, the normal visibility (between 10 and 20 km) significantly decreases the estimated odds of severe delay by 119.17 %. CONCLUSIONS: Compared with other weather factors, wind speed, temperature, and visibility have the greatest impact on the traffic delay levels after a traffic accident, and there are significant differences in the impact under different delay severity. Findings from this study will help policymakers to establish comprehensive differentiating security measures to resolve traffic delays.

Combined Metabolome and Transcriptome Analysis Elucidates Sugar Accumulation in Wucai (Brassica campestris L.).

Wucai (Brassica campestris L.) is a leafy vegetable that originated in China, its soluble sugars accumulate significantly to improve taste quality during maturation, and it is widely accepted by consumers. In this study, we investigated the soluble sugar content at different developmental stages. Two periods including 34 days after planting (DAP) and 46 DAP, which represent the period prior to and after sugar accumulation, respectively, were selected for metabolomic and transcriptomic profiling. Differentially accumulated metabolites (DAMs) were mainly enriched in the pentose phosphate pathway, galactose metabolism, glycolysis/gluconeogenesis, starch and sucrose metabolism, and fructose and mannose metabolism. By orthogonal projection to latent structures-discriminant s-plot (OPLS-DA S-plot) and MetaboAnalyst analyses, D-galactose and ß-D-glucose were identified as the major components of sugar accumulation in wucai. Combined with the transcriptome, the pathway of sugar accumulation and the interact network between 26 DEGs and the two sugars were mapped. CWINV4, CEL1, BGLU16, and BraA03g023380.3C had positive correlations with the accumulation of sugar accumulation in wucai. The lower expression of BraA06g003260.3C, BraA08g002960.3C, BraA05g019040.3C, and BraA05g027230.3C promoted sugar accumulation during the ripening of wucai. These findings provide insights into the mechanisms underlying sugar accumulation during commodity maturity, providing a basis for the breeding of sugar-rich wucai cultivars.

Rapid and sensitive detection of ammonia in water by a long period fiber grating sensor coated with sol-gel silica.

A sensitive ammonia sensor based on long-period fiber grating (LPFG) is designed and manufactured for the detection of ammonia concentration in water. Femtosecond laser direct writing technology is used to write LPFGs on standard single-mode silica fiber. A thin layer doped with basic dyes is coated on the optical fiber for sensing by using the sol-gel method. The thicknesses of sol-gel layers, which play a key role in the sensitivity of the LPFG sensor, were carefully studied. Experimental results show that LPFG with a functional layer of ∼340 nm has the best sensing performance, and the detection limit is 0.08 ppm. The response time of the sensor is less than one minute, and the sensor has good repeatability with a short recovery time. Compared with other organic molecules and ions in water, the proposed LPFG sensor has not only good reusability, but also selectivity for the detection of ammonia.

Ultralow Doppler frequency extraction for the self-mixing dual-frequency laser velocimetry.

In self-mixing dual-frequency laser Doppler velocimetry, the self-mixing Doppler frequency shift of the optical frequency difference is a linear function of the velocity of an external dynamic object; however, it is always ultralow for signal processing. Therefore, an ultralow frequency extraction method based on artificial neural networks (NNs) is presented because NNs can accurately create a fitting function for a Doppler signal and extend the signal to the DC value, increasing the signal length and sampling points without yielding unnecessary influences on the Doppler frequency. We precisely measured Doppler frequencies in the frequency domain with a low sampling rate and calculated the velocities for a target with longitudinal movements. Compared to time-domain extraction, frequency-domain extraction can reflect the complete information of the original Doppler signal. This feature potentially contributes to the signal processing of velocimetry in practical engineering applications.

Rapid and sensitive detection of Staphylococcus aureus by using a long-period fiber grating immunosensor coated with egg yolk antibody.

The rapid and reliable detection of bacteria plays an important role in clinical and veterinary practice. A stable, label free, compact, and sensitive long-period fiber grating (LPFG) sensor based on egg yolk antibody (IgY) was proposed for the detection of Staphylococcus aureus (S. aureus). LPFG was fabricated with laser writing technology, and specific IgY was further immobilized on the grating region and then combined with the corresponding bacteria. S. aureus was detected by tracking the change of resonance wavelength in the LPFG transmission spectrum caused by bacteria-antibody interaction induced by the increase of biological cover thickness and density after the immune reaction. The testing results showed that the proposed sensor was selective and sensitive to S. aureus measurement, and the detection limit is approximately 33 CFU/ml. The proposed antibody immobilization method is very simple, and the optical fiber can be manufactured in batch to reduce the cost. The detection time of the sensor is around 20 min, which is fast and suitable for detection. The assay was successfully applied for the quantitative analysis of S. aureus in natural waters and met the needs of on-site screening trace pathogenic bacteria in food safety control.

Sex Disparities of Genomic Determinants in Response to Immune Checkpoint Inhibitors in Melanoma.

Background: Despite the acknowledged sex-related differences in immune response and immune checkpoint inhibitor (ICI) efficacy, little is known about the sex disparities in melanoma of novel genomic determinants for ICI therapies. Methods: Pretreatment genomic profiles and clinical characteristics of 631 melanoma patients treated with ICIs (i.e., inhibitors of CTLA-4, PD-1/PD-L1, or both) were comprehensively curated. Genomic factors, i.e., significantly mutated genes (SMGs), mutational signatures, and molecular subtypes were identified, and their associations with ICI treatment efficacy in male and female patients were evaluated. Results: Of the 15 SMGs identified in this study, three genes (i.e., CFH, DGKG, and PPP6C) were found to exhibit sex differences with respect to ICI efficacy. Among these, CFH mutations exhibited both response rate and survival benefits in male, but not in female patients. A total of four mutational signatures (i.e., signatures 1, 4, 7, and 11) were extracted. Male patients with signature 4 (also known as smoking-related signature) had an inferior ICI response rate and overall survival. However, this association was not significant in females. An immune subtype based on mutational activities was found to be significantly associated with poor ICI survival in female patients. Conclusion: We uncovered several sex-dependent genomic correlates of response to ICI treatment, such as male-biased CFH mutations and signature 4 and the female-biased immune resistance subtype. The findings derived from this research provide clues for exploring different immunotherapeutic approaches in male and female patients with melanoma.

Morphological characteristics and transcriptome analysis at different anther development stages of the male sterile mutant MS7-2 in Wucai (Brassica campestris L.).

BACKGROUND: The discovery of male sterile materials is of great significance for the development of plant fertility research. Wucai (Brassica campestris L. ssp. chinensis var. rosularis Tsen) is a variety of non-heading Chinese cabbage. There are few studies on the male sterility of wucai, and the mechanism of male sterility is not clear. In this study, the male sterile mutant MS7-2 and the wild-type fertile plant MF7-2 were studied. RESULTS: Phenotypic characteristics and cytological analysis showed that MS7-2 abortion occurred at the tetrad period. The content of related sugars in the flower buds of MS7-2 was significantly lower than that of MF7-2, and a large amount of reactive oxygen species (ROS) was accumulated. Through transcriptome sequencing of MS7-2 and MF7-2 flower buds at three different developmental stages (a-c), 2865, 3847, and 4981 differentially expressed genes were identified in MS7-2 at the flower bud development stage, stage c, and stage e, respectively, compared with MF7-2. Many of these genes were enriched in carbohydrate metabolism, phenylpropanoid metabolism, and oxidative phosphorylation, and most of them were down-regulated in MS7-2. The down-regulation of genes involved in carbohydrate and secondary metabolite synthesis as well as the accumulation of ROS in MS7-2 led to pollen abortion in MS7-2. CONCLUSIONS: This study helps elucidate the mechanism of anther abortion in wucai, providing a basis for further research on the molecular regulatory mechanisms of male sterility and the screening and cloning of key genes in wucai.

Downregulation of miR-892b inhibits the progression of osteoarthritis via targeting cyclin D1 and cyclin D2.

BACKGROUNDS: Osteoarthritis (OA) is an orthopedic inflammatory disease which can cause functional disability and chronic pain. MiRNAs are known to play important roles in OA. To identify the targets for the treatment of OA, bioinformatics analysis was performed to explore differentially expressed miRNAs between OA and normal samples. METHODS: Bioinformatics analysis was conducted to identify differentially expressed miRNAs. To mimic OA in vitro, primary chondrocytes were stimulated with IL-1ß. Meanwhile, flow cytometry was performed to detect the cell apoptosis and cycle distribution. In addition, protein and mRNA expressions were detected by Western blot and RT-qPCR, respectively. Finally, in vivo model of OA was constructed to investigate the function of miR-892b in OA. RESULTS: The data indicated that miR-892b was identified to be upregulated in OA samples. Additionally, miR-892b antagomir markedly reversed IL-1ß-induced growth decline of chondrocytes via inhibiting the apoptosis. IL-1ß notably elevated the expressions of MMP1 and MMP13 and downregulated the level of Aggrecan in chondrocytes, while miR-892b antagomir reversed these phenomena. Meanwhile, cyclin D1 and cyclin D2 were the direct targets of miR-892b. In addition, IL-1ß-induced G1 phase arrest in chondrocytes was partially abolished by of miR-892b antagomir. In vivo study indicated miR-892b antagomir could significantly alleviate the symptom of OA in a rat model. CONCLUSION: MiR-892b antagomir inhibits the progression of OA via targeting Cyclin D1 and Cyclin D2. Thus, our finding might supply a novel target for OA treatment.

MOF-Assisted Synthesis of Highly Mesoporous Cr2O3/SiO2 Nanohybrids for Efficient Lewis-Acid-Catalyzed Reactions.

The facile fabrication of porous solid acids is highly desired for replacing hazardous liquid acids for many acid-catalyzed reactions in the industry. Herein, we present a bottom-up strategy to construct ultrastable mesoporous Cr2O3/SiO2 nanohybrids (denoted as Meso-Cr-Si-O) with highly dispersed Lewis acid sites by pyrolysis of a SiO2@MIL-101 precursor prepared via nanocasting by a reverse double-solvent approach, which can guarantee the efficient encapsulation of SiO2 nanoparticles (NPs) inside the MIL-101 pores. The pore environment of Meso-Cr-Si-O can be well tuned by simply controlling the amount of silica within the MIL-101 pores and the pyrolysis temperature. Pyridine adsorption experiments demonstrate that the density of Lewis acidic sites in the obtained Meso-Cr-Si-O is much higher than that of MIL-101-derived Cr2O3 NPs. Benefitting from its highly mesoporous nanostructure with abundant acid sites, the optimal Meso-Cr-Si-O exhibits a significantly improved catalytic activity for the Lewis-acid-catalyzed Meerwein-Ponndorf-Verley reduction of cyclohexanone with 4.5 times higher yield of cyclohexanol than that of the MIL-101-derived Cr2O3 NPs, representing the first efficient Cr2O3-based catalytic system for this reaction.

The effect of preoperative administration of morphine in alleviating intraoperative pain of percutaneous transforaminal endoscopic discectomy under local anesthesia: A STROBE compliant study.

Local anesthesia is routinely recommended for percutaneous transforaminal endoscopic discectomy (PTED). However, the intense intraoperative pain remains a serious problem. The purpose of the current study is to find a safe and effective method to alleviate the intense pain during PTED for lumbar disc herniation (LDH) under local anesthesia.This study retrospectively analyzed 63 LDH patients who accepted PTED under local anesthesia. Thirty-one patients received intramuscular injection of morphine before PTED, while the other 32 were not. The 10 points visual analogue scale (VAS) was used to assess the patients' maximum leg and back pain. Patients were asked to grade their experiences of surgery and anesthesia on a 5-point Likert-type scale after the surgery. Modified Mac Nab Criteria were used to evaluate the surgical outcomes after 3-month follow-up.The intraoperative VAS scores of patients who accepted preoperative intervention decreased significantly. The postoperative VAS scores of both groups showed no significance. Patients who received preoperative intervention reported a higher subjective satisfaction rate with the surgery experience. According to the Modified Mac Nab criteria, the surgical outcomes of both groups were similar through the 3-month follow-up. After injection of morphine, 4 patients complained nausea and 2 patients experienced vomiting.Preoperative intramuscular injection of morphine could reduce the patients' pain during the PTED surgery and improve the patients' satisfaction without affecting the surgical outcome. Except for a higher incidence of nausea and vomiting, this method is relatively safe and convenient.

Two-hook technique for nucleus extraction in manual sutureless extracapsular cataract extraction.

Nucleus extraction in manual sutureless extracapsular cataract extraction (ECCE) using the 2-hook technique is described. After capsulorhexis and hydrodissection are performed, the nucleus is moved into the anterior chamber and extracted by pulling with a Sinskey hook and pressuring the scleral bed with a Kuglen hook. In a series of 1320 eyes, 85% achieved a corrected visual acuity of 5/10 or better postoperatively. Complications were posterior capsule rupture, vitreous loss, and transient corneal edema. Manual sutureless ECCE using the 2-hook technique is safe and efficient and does not require expensive instrumentation.

Theoretical analysis of the individual contributions of chiral arrays to the chiroptical properties of tris-diamine ruthenium chelates.

Calculations of the excitation energies, oscillator and rotational strengths, and the CD spectra of 16 diastereoisomers of the tris-diamine ruthenium chelates [Ru(en)(3)](2+), [Ru(pn)(3)](2+), and [Ru(bn)(3)](2+) have been performed at the TDDFT/B3LYP/LanL2DZ+6-31G* level including solvent effects. The individual contributions of the chiral arrays, Delta/Lambda octahedral core, delta/lambda twists of the ligand rings, and R/S chiral carbons to the rotational strengths of related transitions have been quantitatively determined and graphically presented. It was found that the three chiral arrays Delta, delta and S each make their contributions to the CD spectra of the chelates with the sign alternated between negative and positive from long wavelength to short, but the intensities of the extrema are different for different chiral arrays. By simply combining the contributions of related chiral arrays in the chelates, all CD spectra of the 16 isomers obtained at the TDDFT level can be well reproduced, and those of the other conformers can also be well predicted, as expected. These findings not only make it possible to determine the absolute configurations and conformations of related chelates in solution from their CD spectra but also provide a deep insight into the chiroptical properties of the chelates.

[Anti-infectious effect of sustained antravitreal amphotericin B drug delivery system on experimental rabbit fungal endophthalmitis of Candida albicans].

OBJECTIVE: To evaluate the efficacy and toxicity of sustained intravitreal amphotericin B drug delivery system (DDS) on experimental rabbit fungal endophthalmitis of Candida albicans. METHODS: Fifty New Zealand rabbits received central vitrectomy were followed by Candida albicans suspension (10(4) colony forming unit, cfu) injection. Rabbits were grouped randomly into five with ten in each as follows: Group A, endophthalmitis control group; Group B, DDS of vehicle alone; Group C, topical treatment with amphotericin B eyedrop; Group D, 5 microg of amphotericin B intravitreal injection every week for two weeks; Group E, DDS contained 1 mg of amphotericin B. Slit-lamp and indirect-ophthalmoscope were performed at different time for two months and vitreous opacity was compared between each group. The intraocular drug concentration was measured with high performance liquid chromatography (HPLC). Light and electron microscope were conducted to evaluate the toxicity of DDS and the effect of vehicle on intraocular structure. Electroretinography (ERG) was employed to evaluate the function of retina before and after the implantation of DDS. RESULTS: Endophthalmitis was obviously inhibited in group E while vitreous was still opacity in other groups. The drug concentration in vitreous cavity was stable and remained for two months in group E while rapidly went down two weeks later in group D. No toxic evidence was found in ocular, liver and kidney tissue and retinal ultrastructure was normal. There was no difference in ERG study before and after the DDS was implanted. CONCLUSIONS: Sustained intravitreal amphotericin B DDS can significantly suppress the formation of fungal colony and inhibit the development of infection with long and stable intraocular drug concentration maintenance. The vehicle and amphotericin B DDS are safe to intraocular structure.