A Symbol layout classification for mathematical formula using layout context

We describe a symbol classification technique for identifying the expected locations of neighboring symbols in mathematical expressions. We use the seven symbol layout classes of the DRACULAE math notation parser (Zanibbi, et al., 2002) to represent expected locations for neighboring symbols: Ascender, Descender, Centered, Open Bracket, Non-Scripted, Variable Range (e.g., integrals) and Root. A new feature based on the shape context (Belongie, et al., 2002), named layout context, is used to describe the arrangement of neighboring symbols relative to a reference symbol, and the nearest neighbor rule is used for classification. 1917 mathematical symbols from the University of Washington III document database are used in our experiments. Using a leave-one-out estimate, our best classification rate reaches nearly 80%. In our experiments, we find that the size of the reference symbol neighborhood area, the number and the sampling positions of the points of the key points model representing a symbol\u27s location, play important roles in the classification process

Identifying Layout Classes for Mathematical Symbols Using Layout Context

We describe a symbol classification technique for identifying the expected locations of neighboring symbols in mathematical expressions. We use the seven symbol layout classes of the DRACULAE math notation parser (Zanibbi, Blostein, and Cordy, 2002) to represent expected locations for neighboring symbols: Ascender, Descender, Centered, Open Bracket, Non-Script, Variable Range (e.g. integrals) and Square Root. A new feature based on shape contexts (Belongie et al., 2002) named layout context is used to describe the arrangement of neighboring symbol bounding boxes relative to a reference symbol, and the nearest neighbor rule is used for classification. 1917 mathematical symbols from the University of Washington III document database are used in our experiments. Using a leave-one-out estimate, our best classification rate reaches nearly 80%. In our experiments, we find that the size of the symbol neighborhood, and number and arrangement of key points representing a symbol affect performance significantly

Polypropylene based anion exchange fiber for enrichment and determination of trace indium by GFAAS

Indium was enriched and separated by a new polypropylene based anion exchange fiber before determined by graphite furnace atomic absorption spectrometry (GFAAS). Indium can be enriched quantitatively by 0.1 g of fiber at the flow rate within 6 mL·min-1 in the pH 4 and can be desorbed quantitatively with 10 mL of 1.0 M nitric acid from the fiber column. The fibers were soaked in 2 M sodium hydroxide sodium hydroxide solution for activation and were washed with distilled water at least thirty times until neutral for regeneration, The saturated capacity of the fiber for In(III) was 1.32 mg·g-1. The activation energy (Ea) of the fiber adsorption In(III) was 89.3 kJ·mol-1. The method was used to enrich trace In(III) in artificial samples solution and zinc concentrate solution before determination. The method detection limit was 0.08 ng·mL-1, the recoveries were 96.8-101%, and the relative standard deviations (RSD) were 0.1-2.1%. KEY WORDS: Anion exchange fiber, Separation, Enrichment, Indium, GFAAS Bull. Chem. Soc. Ethiop. 2011, 25(2), 295-298

Minimally invasive surgery for uterine fibroids

The incidence of uterine fibroids, which comprise one of the most common female pelvic tumors, is almost 70–75% forwomen of reproductive age. With the development of surgical techniques and skills, more individuals prefer minimallyinvasive methods to treat uterine fibroids. There is no doubt that minimally invasive surgery has broad use for uterinefibroids. Since laparoscopic myomectomy was first performed in 1979, more methods have been used for uterine fibroids,such as laparoscopic hysterectomy, laparoscopic radiofrequency volumetric thermal ablation, and uterine artery embolization,and each has many variations. In this review, we compared these methods of minimally invasive surgery for uterinefibroids, analyzed their benefits and drawbacks, and discussed their future development

Optimization of enantioselective production of chiral epichlorohydrin catalyzed by a novel epoxide hydrolase from domestic duck liver by response surface methodology

Enantiopure epichlorohydrin is a valuable epoxide intermediate for preparing optically active pharmaceuticals. In the present study, a novel epoxide hydrolase prepared from domestic duck liver was used as biocatalyst for producing (S)-epichlorohydrin which preparation process was optimized by response surface methodology. Response surface methodology was performed to evaluate the effects of reaction temperature, pH and reaction time on production of (S)-epichlorohydrin by the novel epoxide hydrolase. (S)-epichlorohydrin production was optimized by Box-Behnken. Three reaction parameters were optimized as follows: pH value 7.10, reaction temperature 32.44°C and reaction time11.06 h. The adequately high R2 value 0.9599 and F score 13.29 indicated the statistical significance of the model. The enantioselective excess of (S)-epichlorohydrin after optimization was 86.14% while thepredicted value was 85.55%. In conclusion, enantioselective hydrolysis conditions optimization to enhance optical purity of (S)-epichlorohydrin could be easily and effectively done by response surfacemethodology; the developed production process indicated the novel epoxide hydrolase from domestic duck liver was high efficient biocatalyst for preparing enantiopure epichlorohydrin

Impact of operative vaginal delivery on early postpartum pelvic floor function in primipara

Objective To evaluate the effect of operative vaginal delivery on early postpartum pelvic floor function in primipara. Methods Clinical data of 345 parturients with vaginal delivery were collected. According to the mode of delivery， all cases were divided into the natural delivery group （n = 170）， vacuum-assisted delivery group （n = 130） and forceps-assisted delivery group（n = 45）. The pelvic floor muscle strength and three-dimensional ultrasound of the pelvic floor were examined 6-12 weeks after delivery. The abnormal rate of pelvic floor muscle strength， bladder neck mobility rate， cystocele rate， enlargement rate of levator hiatal area， levator ani muscle injury rate， anal sphincter injury rate were statistically compared among three groups. Results There were no significant differences in the maternal age， body mass index， gestational weight gain， gestational age and newborn birth weight among three groups （all P > 0.05）. The abnormal rate of pelvic floor muscle strength in the forceps-assisted delivery group was higher than that in the natural delivery group （P < 0.017）， whereas there were no significant differences in the remaining pairwise comparison （both P > 0.017）. The levator ani muscle injury rate in the forceps-assisted delivery group was higher than those in the natural delivery and vacuum-assisted delivery groups （both P < 0.017）， and the levator ani muscle injury rate in the vacuum-assisted delivery group was higher than that in the natural delivery group （P < 0.001）. There were no significant differences in the abnormal rate of bladder neck mobility， cystocele rate， enlargement rate of levator hiatal area and anal sphincter injury rate among three groups （all P > 0.05）. Pelvic floor ultrasound indicated that among 52 women with pelvic floor muscle injury， 9 cases had normal pelvic floor muscle strength. The results of consistency test between two methods were Kappa = 0.061 and P = 0.029. Conclusions Compared with the natural delivery group， the pelvic floor injury is the most severe and the levator ani muscle injury rate is the highest in the forceps-assisted delivery group. These two methods are independent of each other. Pelvic floor ultrasound can clearly show pelvic floor muscle injury after delivery， which plays an important role in the postpartum screening of pelvic floor

Spotlight on iron and ferroptosis: research progress in diabetic retinopathy

Iron, as the most abundant metallic element within the human organism, is an indispensable ion for sustaining life and assumes a pivotal role in governing glucose and lipid metabolism, along with orchestrating inflammatory responses. The presence of diabetes mellitus (DM) can induce aberrant iron accumulation within the corporeal system. Consequentially, iron overload precipitates a sequence of important adversities, subsequently setting in motion a domino effect wherein ferroptosis emerges as the utmost pernicious outcome. Ferroptosis, an emerging variant of non-apoptotic regulated cell death, operates independently of caspases and GSDMD. It distinguishes itself from alternative forms of controlled cell death through distinctive morphological and biochemical attributes. Its principal hallmark resides in the pathological accrual of intracellular iron and the concomitant generation of iron-driven lipid peroxides. Diabetic retinopathy (DR), established as the predominant cause of adult blindness, wields profound influence over the well-being and psychosocial strain experienced by afflicted individuals. Presently, an abundance of research endeavors has ascertained the pervasive engagement of iron and ferroptosis in the microangiopathy inherent to DR. Evidently, judicious management of iron overload and ferroptosis in the early stages of DR bears the potential to considerably decelerate disease progression. Within this discourse, we undertake a comprehensive exploration of the regulatory mechanisms governing iron homeostasis and ferroptosis. Furthermore, we expound upon the subsequent detriments induced by their dysregulation. Concurrently, we elucidate the intricate interplay linking iron overload, ferroptosis, and DR. Delving deeper, we engage in a comprehensive deliberation regarding strategies to modulate their influence, thereby effecting prospective interventions in the trajectory of DR’s advancement or employing them as therapeutic modalities