关键词： polyhydroxyalkanoates   microwave-assisted extraction   mixed microbial cultures   bacterial biopolymer   biopolymer extraction  

摘要： BACKGROUND: Polyhydroxyalkanoates (PHAs) are a class of biodegradable biopolymers produced and accumulated by microorganisms. PHAs are recovered from microbial biomass through the stages of pretreatment, extraction and purification. An alternative recovery method is microwave-assisted extraction (MAE), which involves the supply of energy through an electromagnetic field, generating high temperatures in reduced times. A study to evaluate the recovery of PHAs from mixed microbial cultures was conducted using MAE. This method was evaluated through a four-factorial experimental design, with the efficiency as the evaluated response. PHAs were also recovered using conventional heat extraction as control. RESULTS: It was found that the highest efficiency achieved using MAE was 68 +/- 1.2% (w/w), which was close to the 66 +/- 5.3% (w/w) obtained using conventional heat extraction. The following combination of factors corresponded to the optimum conditions of experimental design: extraction time of 1 min, temperature of 130 degrees C, chloroform-to-methanol ratio of 1:1 and solvent-to-biomass ratio of 20 volumes. The efficiency increased substantially when the solvent-to-biomass ratio and chloroform-to-methanol ratio increased, although the temperature was the least significant factor. Functional groups, decomposition temperatures (263-309 degrees C) and melting point (158 degrees C) of MAE-recovered PHAs were similar to those measured for commercial poly[(3-hydroxybutyrate)-co-(3-hydroxyvalerate)]. CONCLUSIONS: MAE is a never-before-reported useful method for recovering PHAs from mixed microbial cultures, which provides for a high extraction efficiency and quality of the recovered biopolymers. (c) 2021 Society of Chemical Industry (SCI).

关键词： suburethral sling   urinary incontinence, stress   dyspareunia  

摘要： Purpose: Limited data exist regarding sexual function after single incision sling (SIS) surgery. We compared sexual function 36 months postoperatively between patients undergoing SIS and transobturator sling (TMUS) for treatment of stress urinary incontinence. Materials and Methods: Assessment of sexual function was a planned secondary objective of this prospective, multi-center study that enrolled women to Solyx SIS or Obtryx II TMUS. The primary study aim was to compare efficacy and safety using non-inferiority design at 36 months. Patient-reported outcomes of sexual function were assessed at baseline and 6, 12, 18, 24 and 36 months using Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12). Changes in sexual function were analyzed within and between groups. Outcomes for patients requiring surgical retreatment were determined. Results: Baseline characteristics were balanced using propensity score stratification (N=141 SIS, N=140 TMUS). Groups were similar in age, body mass index and concomitant surgery performed. Average length of followup was 30 months. Baseline sexual activity was similar (123/141 SIS, 114/140 TMUS, p=0.18). Severity of urinary incontinence did not correlate with baseline sexual activity. Mean PISQ-12 scores increased significantly from baseline to 36 months for both groups, indicating better sexual function at each visit. There were no significant differences in PISQ-12 scores between groups except at 36 months, where the difference was small (-2.5, 95% CI [-4.7, 0.2]). Among patients undergoing surgical retreatment (9/281, 3%), improvement in sexual function was maintained. De novo dyspareunia was rare following both treatments (SIS 1/141, TMUS 0/140, p=1.00). Conclusions: Patients have significant improvement in sexual function after SIS and TMUS. De novo sexual pain is low after sling surgery.

关键词： Dynamic liquid viscosity   Alternative refrigerants   R-1225ye(Z) and R-1243zf   Modified Joback group contribution method  

摘要： This paper aims to find parameters for the contribution of elements "-F" and "=C<" on the dynamic liquid viscosity. The found contribution of the element "-F" and "=C<" for the dynamic liquid viscosity, 707.816 for eta(a) and -2.3648 for eta(b) for element "-F" and -919.101 for eta(a) and 2.21487 for eta(b) for element "=C<" can be used to predict the dynamic viscosity of hydrofluoroolefins (HFOs) and hydrochlorofluoroolefins (HCFOs). This paper also proposes a modified Joback's method to improve the accuracy of the prediction of the dynamic liquid viscosity. The study of six potential refrigerants R-1224yd(Z), R-1233zd(E), R-1234yf, R-1234ze(E), R-1234ze(Z), and R-1336mzz(Z) shows that the proposed modified Joback's method is more accurate than the original Joback's method. The dynamic liquid viscosity of potential refrigerants R-1243zf and R-1225ye(Z) was determined with the modified Joback's method.

关键词： Transcranial magnetic stimulation   Electroencephalography   Synchrosqueezing transform   Hilbert-Huang transform   Morlet wavelet transform  

摘要： Background: Transcranial magnetic stimulation combined with electroencephalography (TMS-EEG) has become a powerful tool to assess cortical properties, such as cortical oscillation. An accurate and robust time-frequency analysis tool with high resolution would facilitate the understanding of TMS-evoked oscillations. Methods: The synchrosqueezing transform (SST), the Hilbert-Huang transform (HHT) and the Morlet wavelet transform (MWT) were used to analyze TMS-evoked oscillations. Firstly, we generated simulation data, and compared the performance of three methods to analyze the time-frequency characteristics of simulation data;then, we collected TMS-EEG data from normal people (NOR), patients with minimally conscious state (MCS) and vegetative state (VS). SST was used to analysis time-frequency characteristics of TMS-evoked oscillations in different states of consciousness. In addition, relative power (RP) and spectral entropy (SeEn) were calculated based on SST results. Results: Simulation results showed that SST detected rhythm characteristics of instantaneous signal and background signal more completely. Results of NOR group showed that SST could more accurately detect TMS-evoked oscillations with high frequency resolution than HHT and MWT. The main frequency of TMS-evoked oscillations for DOC patients (MCS: 11.73 +/- 1.94 Hz;VS: 2.06 +/- 0.25 Hz) was different from that of NOR (22.79 +/- 1.42 Hz) based on SST. RP and SeEn further verified the differences of the main frequency of TMS-evoked oscillations between NOR and DOC patients. Conclusions: The results suggest that SST is a robust analytical method and outperforms HHT and MWT in studying TMS-evoked oscillations. The main frequency of TMS-evoked oscillations of DOC was lower than that of NOR.

关键词： Metasurface lens   Alternative plasmonics   Peano space filling curve   Conformal Talbot effect  

摘要： Focusing performance of Peano space filling curve-based fractal construction is studied at communication wavelength of 1550 nm. Lensing by diffraction from these finite-sized 2D devices of the first three iterated fractal lattice system constructed with gallium-doped zinc oxide is computationally demonstrated in a systematical manner. In this regard, focusing performance parameters such as efficiency, spot size, focal length, focal depth, and fill-factor are determined on the basis of geometrical parameter sweep and fractal generation through finite difference timedomain simulations. Focusing efficiency from 48% up to 60%, absolute efficiency from 14% up to 33.98%, numerical aperture values from 0.127 up to 0.96, spot sizes from 1.02 lambda SP up to 11.25 lambda SP, and focal depth larger than focal length are introduced by all computational samples. A conformal Talbot effect is assigned when appropriate geometric values are provided. A novel perspective is offered by a newly adapted fractal lattice to optics via an alternative plasmonic material perspective, especially for an optical fiber component.

关键词： Fish oil   Morbidity   Olive oil   Preterm   Total parenteral nutrition  

摘要： Objective To compare clinical outcomes of using different alternative lipid emulsions for longer durations in babies who are at high risk for preterm morbidities. Methods Preterm infants born <= 30 wk receiving SMOFlipid versus Clinoleic with longer durations (>= 14 d) were included in this retrospective study. The authors compared demographic features, clinical applications, and morbidities between epochs: epoch 1 (Clinoleic, July 2017-June 2018) versus epoch 2 (SMOFlipid, July 2018-June 2019). Results A total of 91 infants were included in the study. In bivariate analysis;moderate bronchopulmonary dysplasia (BPD) (p = 0.000) and composite outcome [BPD, retinopathy of prematurity (ROP) needed treatment, cholestasis and late-onset sepsis and/or mortality] rates were significantly higher (p = 0.043) in Clinoleic group. In multivariate logistic regression analysis, it was found that the type of lipid emulsion used had no significant effect on these morbidities. Conclusions Since both groups had comparable morbidity and mortality, both lipid emulsions are equally safe in preterm babies requiring parenteral nutrition.

关键词： elite control   HIV cure   HIV persistence   HIV remission   HIV reservoir   immune control   posttreatment control  

摘要： Purpose of review To provide an overview of studies to date that have identified posttreatment controllers (PTCs) and to explore current evidence around clinical characteristics, immune effector function, and inflammatory and viral reservoir characteristics that may underlie the control mechanism. Recent findings PTCs are broadly defined as individuals capable of maintaining control of HIV replication after cessation of antiretroviral therapy (ART). While starting ART early after HIV infection is associated with PTC, genetic disposition or CD8+ T-cell function do not appear to explain this phenomenon, but these features have not been exhaustively analyzed in PTCs. A lower frequency of latently infected cells prior to stopping ART has been associated with achieving PTC, including a lower level of intact HIV DNA, but more studies are needed to map the genetic location, epigenetic characteristics, and tissue distribution of the intact HIV reservoir in PTCs. Current studies are small and heterogeneous and there is a significant need to agree on a uniform definition of PTC. Many aspects of PTC are still unexplored including whether specific features of genetic disposition, immune effector functions, and/or viral reservoir characteristics play a role in PTC. A large multisite international cohort study could aide in providing the important insights needed to fully understand PTC.