The phenolic composition and antioxidant activity of tea with different parts of Sideritis condensate at different steeping conditions

Tea with different parts (flower, leaf, seed) of Sideritis condensate infused at different temperatures (60 and 100°C) and times (5, 10 and 30 minutes) were assessed for their phenolic composition and antioxidant activities. Leaf tea had the highest total phenolic content where as seed tea had the lowest.Leaves soaked at 100°C for 10 minutes had the highest total phenolic content. Total phenolic content of flower tea increased with increase in extraction temperature and time. Radical scavenging activities of leaves infused at 60°C for 5, 10 and 30 minutes were statistically in the same group but lower than those of leaves soaked at 100°C for 5, 10 and 30 min. The major phenolic compound identified from almost all aqueous infusions was the p-coumaric acid. The conditions of tea prepared from leaves of the Sideritis condensata at 100°C for 5, 10 and 30 minutes are the most appropriate conditions in regard to extraction of the highest total phenolics and the strongest antioxidant activity

Multicarrier Rate-Splitting Multiple Access: Superiority of OFDM-RSMA over OFDMA and OFDM-NOMA

Rate-splitting multiple access (RSMA) is a multiple access technique generalizing conventional techniques, such as, space-division multiple access (SDMA), non-orthogonal multiple access (NOMA), and physical layer multi-casting, which aims to address multi-user interference (MUI) in multiple-input multiple-output (MIMO) systems. In this study, we leverage the interference management capabilities of RSMA to tackle the issue of inter-carrier interference (ICI) in orthogonal frequency division multiplexing (OFDM) waveform. We formulate a problem to find the optimal subcarrier and power allocation for downlink transmission in a two-user system using RSMA and OFDM and propose a weighted minimum mean-square error (WMMSE)-based algorithm to obtain a solution. The sum-rate performance of the proposed OFDM-RSMA scheme is compared with that of conventional orthogonal frequency division multiple access (OFDMA) and OFDM-NOMA by numerical results. It is shown that the proposed OFDM-RSMA outperforms OFDM-NOMA and OFDMA under ICI in diverse propagation channel conditions owing to its flexible structure and robust interference management capabilities.Comment: Updated version of published paper in IEEE Communications Letters with correction in optimization problem (17b

Particle size effects in the thermal conductivity enhancement of copper-based nanofluids

We present an analysis of the dispersion characteristics and thermal conductivity performance of copper-based nanofluids. The copper nanoparticles were prepared using a chemical reduction methodology in the presence of a stabilizing surfactant, oleic acid or cetyl trimethylammonium bromide (CTAB). Nanofluids were prepared using water as the base fluid with copper nanoparticle concentrations of 0.55 and 1.0 vol.%. A dispersing agent, sodium dodecylbenzene sulfonate (SDBS), and subsequent ultrasonication was used to ensure homogenous dispersion of the copper nanopowders in water. Particle size distribution of the copper nanoparticles in the base fluid was determined by dynamic light scattering. We found that the 0.55 vol.% Cu nanofluids exhibited excellent dispersion in the presence of SDBS. In addition, a dynamic thermal conductivity setup was developed and used to measure the thermal conductivity performance of the nanofluids. The 0.55 vol.% Cu nanofluids exhibited a thermal conductivity enhancement of approximately 22%. In the case of the nanofluids prepared from the powders synthesized in the presence of CTAB, the enhancement was approximately 48% over the base fluid for the 1.0 vol.% Cu nanofluids, which is higher than the enhancement values found in the literature. These results can be directly related to the particle/agglomerate size of the copper nanoparticles in water, as determined from dynamic light scattering

Glaucoma after Penetrating Keratoplasty: Incidence, Risk Factors, and Management

Purpose. To report the incidence and risk factors for postkeratoplasty glaucoma (PKG), as well as its management. Subjects and Methods. 122 eyes, (43% with pseudophakic and aphakic bullous keratopathy (PABK)) which underwent penetrating keratoplasty (PK), were analyzed. Results. The rate of PKG development was 34% within 39 months of follow-up. PABK, corneal perforations, keratitis, and previous high intraocular pressure (PHIOP) were high risk factors for PKG. Glaucoma was controlled medically in 62% of PKG cases. Surgery (Ex-PRESS shunt in 63%) and diode laser cyclophotocoagulation were applied in others (38%). The rate of postoperative complications and graft survival was similar in eyes with and without PKG. Conclusion. PHIOP, preoperative diagnoses other than keratoconus, and corneal dystrophies were highly associated with PKG. Ex-PRESS shunts were effective in refractory PKG. If glaucoma is controlled, it is possible to obtain similar rates of graft survival and postoperative complications in eyes with and without PKG

Phenolic components, antioxidant activity, and mineral analysis of Capparis spinosa L

In addition to being consumed as food, caper (Capparis spinosa L.) fruits are also used in folk medicine to treat inflammatory disorders, such as rheumatism. C. spinosa L. is rich in phenolic compounds, making it increasingly popular because of its components’ potential benefits to human health. We analyzed a number of individual phenolic compounds and investigated in vitro biological activities of C. spinosa L. Sixteen phenolic constituents were identified using reverse phase-high performance liquid chromatography (RP-HPLC). Total phenolic compounds (TPCs), ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were used as determinants of antioxidant capacity. C. spinosa L. exhibited strong antioxidant activity and contained high levels of antioxidant compounds. Gentisic, sinapic and benzoic acid were detected in C. spinosa L. No gallic acid, proto-catechuic acid, proto-catechuic aldehyde, chlorogenic acid, p-OH benzoic acid, vanillic acid, caffeic acid, syringic acid, vanillin, syringaldehyde, p-coumaric acid, ferulic acid or rosmarinic acid were identified. Iron and zinc were present at high levels in samples. C. spinosa L. appears to be a good source of antioxidants and minerals that might serve to protect health and combat several diseases.Key words: Antioxidant, capers, Capparis spinosa L., phenolics

Urodynamic and Frequency-Volume Chart Parameters Influencing Anticholinergic Resistance in Patients With Neurogenic Detrusor Overactivity

Purpose Neurogenic detrusor overactivity (NDOA) is characterized by involuntary detrusor muscle contractions during bladder filling in patients with neurological disorders. Anticholinergic therapy is the primary treatment; however, the reasons for treatment resistance in NDOA are not well understood. This study aimed to identify predictors of treatment failure by comparing urodynamic and frequency-volume chart data between patients with NDOA who respond and patients who do not respond to anticholinergic therapy. Methods We reviewed the records of 362 patients presenting with lower urinary tract symptoms and selected 85 who had NDOA and were on anticholinergic therapy. Ultimately, 67 patients were analyzed. We categorized these individuals into responders (group R) and nonresponders (group NR) based on clinical and urodynamic improvements. Three-day frequencyvolume charts and urodynamic study results were retrospectively reviewed. Results Of the 85 initial patients, 12 refused medication, and 6 were lost to follow-up. Pre- to posttreatment changes differed significantly between groups in the number of urgency urinary incontinence (UUI) episodes per 24 hours (P=0.001), maximum cystometric capacity (mL, P=0.003), NDOA frequency (P=0.004), and bladder compliance (mL/cm H2O, P=0.003). Multivariate analysis revealed that NDOA frequency (P=0.014) and UUI episodes per 24 hours (P=0.002) were significant factors associated with treatment failure. Conclusions NDOA varies according to underlying neurological conditions. The frequencies of UUI episodes and NDOA in urodynamic studies can predict resistance to initial anticholinergic treatment