Multi-harmonic near-infrared-ultraviolet dual-comb spectrometer.

Dual-comb spectroscopy in the ultraviolet (UV) and visible would enable broad bandwidth electronic spectroscopy with unprecedented frequency resolution. However, there are significant challenges in generation, detection, and processing of dual-comb data that have restricted its progress in this spectral region. In this work, we leverage robust 1550 nm few-cycle pulses to generate frequency combs in the UV-visible. We combine these combs with a wavelength multiplexed dual-comb spectrometer and simultaneously retrieve 100 MHz comb-mode-resolved spectra over three distinct harmonics at 386, 500, and 760 nm. The experiments highlight the path to continuous dual-comb coverage spanning 200-750 nm, offering extensive access to electronic transitions in atoms, molecules, and solids.

Broadband 1-GHz mid-infrared frequency comb.

Mid-infrared (MIR) spectrometers are invaluable tools for molecular fingerprinting and hyper-spectral imaging. Among the available spectroscopic approaches, GHz MIR dual-comb absorption spectrometers have the potential to simultaneously combine the high-speed, high spectral resolution, and broad optical bandwidth needed to accurately study complex, transient events in chemistry, combustion, and microscopy. However, such a spectrometer has not yet been demonstrated due to the lack of GHz MIR frequency combs with broad and full spectral coverage. Here, we introduce the first broadband MIR frequency comb laser platform at 1 GHz repetition rate that achieves spectral coverage from 3 to 13 µm. This frequency comb is based on a commercially available 1.56 µm mode-locked laser, robust all-fiber Er amplifiers and intra-pulse difference frequency generation (IP-DFG) of few-cycle pulses in χ(2) nonlinear crystals. When used in a dual comb spectroscopy (DCS) configuration, this source will simultaneously enable measurements with µs time resolution, 1 GHz (0.03 cm-1) spectral point spacing and a full bandwidth of >5 THz (>166 cm-1) anywhere within the MIR atmospheric windows. This represents a unique spectroscopic resource for characterizing fast and non-repetitive events that are currently inaccessible with other sources.

Amniotic fluid glucose level in PPROM pregnancies: a glance at the old friend.

INTRODUCTION: To determine the amniotic fluid glucose levels in pregnancies complicated by preterm prelabor rupture of membranes (PPROM) based on the presence of microbial invasion of the amniotic cavity and/or intra-amniotic inflammation. METHODS OF STUDY: A total of 142 women with singleton pregnancies complicated by PPROM between gestational ages 24 + 0 and 36 + 6 weeks were included. Amniocentesis was performed at the time of admission. The assessments of microbial invasion of the amniotic cavity (using both cultivation and non-cultivation techniques) and intra-amniotic inflammation (amniotic fluid interleukin-6 levels ≥ 3000 pg/mL) were performed on all the women. Based on the presence of microbial invasion of the amniotic cavity and/or intra-amniotic inflammation, the women were further categorized into the subgroups: (i) intra-amniotic infection (the presence of both microbial invasion of the amniotic cavity and intra-amniotic inflammation); (ii) sterile intra-amniotic inflammation (the presence of intra-amniotic inflammation without microbial invasion of the amniotic cavity); (iii) colonization (the presence of microbial invasion of the amniotic cavity without intra-amniotic inflammation); and (iv) negative amniotic fluid (the absence of either microbial invasion of the amniotic cavity or intra-amniotic inflammation). Amniotic fluid glucose levels were assessed using enzymatic reference method with hexokinase. RESULTS: There was a difference in the amniotic fluid glucose levels among the women with intra-amniotic infection, sterile intra-amniotic inflammation, colonization, and those with negative amniotic fluid (p < .0001). No difference was found in the amniotic fluid glucose levels between women with intra-amniotic infection and those with sterile intra-amniotic inflammation [infection: median 11.6 mg/dL (0.7 mmol/L) vs. sterile: median 6.3 mg/dL (0.4 mmol/L); p = .41] and between women with colonization and negative amniotic fluid [colonization: median 21.6 mg/dL (1.2 mmol/L) vs. negative: median 23.4 mg/dL (1.3 mmol/L; p = .67]. Women with intra-amniotic infection and sterile intra-amniotic inflammation had lower amniotic fluid glucose levels than women with colonization and with negative amniotic fluid in crude analysis as well as after adjustment for gestational age at sampling. Amniotic fluid glucose level of 10 mg/dL (0.56 mmol/L) was the optimal concentration for the identification of intra-amniotic inflammation in women with PPROM. CONCLUSIONS: The presence of intra-amniotic inflammation was associated with lower amniotic fluid glucose levels in singleton pregnancies complicated with PPROM. An amniotic fluid glucose level of 10 mg/dL (0.56 mmol/L) was the optimal concentration for the identification of intra-amniotic inflammation in PPROM pregnancies. In the absence of better amniotic fluid markers, amniotic glucose could be used as a marker of intra-amniotic inflammation, with very good specificity in PPROM pregnancies.

History and current trends in the treatment of idiopathic overactive bladder.

OBJECTIVE: Historical and current view on the therapy of overactive bladder. METHODS: This review summarizes the historical approach and current therapy of overactive bladder. The articles were gathered from Pubmed and Scopus databases. Studies published before December 2020 were used for the review. RESULTS AND CONCLUSION: Overactive bladder is a condition that quite a lot reduces the quality of life of our patients. Our therapeutic approach starts with non-pharmacological treatment, such as pelvic floor exercises. The next step is a pharmacological approach. The entry level drug is trospium. If the effect is not sufficient, propiverine, solifenacin, fesoterodine, darifenacin or mirabegron are used. Electrostimulation or botulinum toxin A application is an option only in cases that didnt respond to pharmacological treatment. It is safe to say, that in the end, there is a way of reducing the severity of overactive bladder symptoms for every  patient.

Cervical Gardnerella vaginalis in women with preterm prelabor rupture of membranes.

OBJECTIVE: To determine the association between microbial invasion of the amniotic cavity (MIAC) and/or intra-amniotic inflammation (IAI) and the cervical prevalence of Gardnerella vaginalis DNA in pregnancies with preterm prelabor rupture of membrane (PPROM). METHOD: In total, 405 women with singleton pregnancies complicated with PPROM were included. Cervical fluid and amniotic fluid samples were collected at the time of admission. Bacterial and G. vaginalis DNA were assessed in the cervical fluid samples using quantitative PCR technique. Concentrations of interleukin-6 and MIAC were evaluated in the amniotic fluid samples. Loads of G. vaginalis DNA ≥ 1% of the total cervical bacterial DNA were used to define the cervical prevalence of G. vaginalis as abundant. Based on the MIAC and IAI, women were categorized into four groups: with intra-amniotic infection (both MIAC and IAI), with sterile IAI (IAI without MIAC), with MIAC without IAI, and without either MIAC or IAI. RESULTS: The presence of the abundant cervical G. vaginalis was related to MIAC (with: 65% vs. without: 44%; p = 0.0004) but not IAI (with: 52% vs. without: 48%; p = 0.70). Women with MIAC without IAI had the highest load of the cervical G. vaginalis DNA (median 2.0 × 104 copies DNA/mL) and the highest presence of abundant cervical G. vaginalis (73%). CONCLUSIONS: In women with PPROM, the presence of cervical G. vaginalis was associated with MIAC, mainly without the concurrent presence of IAI.

All-fiber frequency comb at 2 µm providing 1.4-cycle pulses.

We report an all-fiber approach to generating sub-2-cycle pulses at 2 µm and a corresponding octave-spanning optical frequency comb. Our configuration leverages mature erbium:fiber laser technology at 1.5 µm to provide a seed pulse for a thulium-doped fiber amplifier that outputs 330 mW average power at a 100 MHz repetition rate. Following amplification, nonlinear self-compression in fiber decreases the pulse duration to 9.5 fs, or 1.4 optical cycles. The spectrum of the ultrashort pulse spans from 1 to beyond 2.4 µm and enables direct measurement of the carrier-envelope offset frequency. Our approach employs only commercially available fiber components, resulting in a design that is easy to reproduce in the larger community. As such, this system should be useful as a robust frequency comb source in the near-infrared or as a pump source to generate mid-infrared frequency combs.

Effects of Coadsorbed Water on the Heterogeneous Photochemistry of Nitrates Adsorbed on TiO2.

Nitric acid, a well-known sink of NO x gases in the atmosphere, has been found to be photoactive while adsorbed on tropospheric particles. When adsorbed onto semiconductive metal oxides, nitrate's photochemical degradation can be interpreted as a photocatalytic process. Yet, the photolysis of nitrate ions on the surface of aerosols can also be initiated by changes in the symmetry of the ion upon adsorption. In this study, we use quantum chemistry to model the vibrational spectra of adsorbed nitrate on TiO2, a semiconductor component of atmospheric aerosols, and determine the kinetics of the heterogeneous photochemical degradation of nitrate under simulated solar light. Frequencies and geometry calculations suggest that the symmetry of chemisorbed nitrate ion depends strongly on coadsorbed water, with water changing the reactive surface of TiO2. Upon irradiation, surface nitrate undergoes photolysis to yield nitrogen-containing gaseous products including NO2, NO, HONO, and N2O, in proportions that depend on relative humidity (RH). In addition, the heterogeneous photochemistry rate constant decreases an order of magnitude, from (5.7 ± 0.1) × 10-4 s-1 on a dry surface to (7.1 ± 0.8) × 10-5 s-1 when nitrate is coadsorbed with water above monolayer coverage. Little is known about the roles of coadsorbed water on the heterogeneous photochemistry of nitrates on TiO2, along with its impact on the chemical balance of the atmosphere. This work discusses the roles of water in the photolysis of surface nitrates on TiO2 and the concomitant renoxification of the atmosphere.

Comparison of two long-term gestagen regimens in the management of recurrent vulvovaginal candidiasis: A pilot study.

Vulvovaginal candidiasis (VVC) is a hormonal-dependent infection but in contrast to sporadic VVC, therapy of recurrent vulvovaginal candidiasis (RVVC) is still unsolved. Long-term administration of medroxyprogesterone acetate was evaluated for the management of RVVC. Overall, 20 patients were treated with Depo-Provera; 14 patients were treated with Provera. Gestagen therapy was evaluated based on visual analogue scale (VAS), the frequency of attacks, the side effects of gestagens and the consumption of antifungals. There was a reduced symptomatology in both of the groups and substantial reduction in antifungal drug consumption during the second year of gestagen use. Twenty-four patients (70.6%) evaluated their condition regarding the vulvovaginal area as improvement (VAS decrease of 3-5 points). Five patients (14.7%) mentioned minimal or no improvement. Further, a number of antifungal drug-treated episodes dropped dramatically during the study period. Both regimes provided similar results, but five patients from the Depo-Provera group had to withdraw from gestagen therapy. Gestagen supplementation ameliorated the quality of life for the majority of patients with RVVC and suggested a potential role in the management of this syndrome, even if beneficial effect was evident after longer application, and some patients met with side effects that led to an interruption of therapy.

Photochemistry of nitrate chemisorbed on various metal oxide surfaces.

Atmospheric aerosols are known to provide an important surface for gas-solid interfaces that can lead to heterogeneous reactions impacting tropospheric chemistry. In this work, α-Fe2O3, TiO2, γ-Al2O3, SiO2 and ZnO, common components of atmospheric aerosols, served as models to investigate the gas-solid interface of nitric acid with aerosols in the presence of simulated solar radiation. Adsorbed nitrate and gaseous products can be continuously monitored with infrared spectroscopy (IR). Kinetic studies of adsorbed species were carried out using attenuated total reflectance infrared spectroscopy (ATR-FTIR). Ex situ simultaneous infrared spectroscopy of gas-phase products using a 2 m long path cell allowed the detection of gaseous products at early stages of the heterogeneous photochemical reaction. In addition, photoactive gaseous products, such as HONO, were detected as gas analysis was carried out outside the region of irradiation. All reactions were found to be first order with respect to adsorbed nitric acid and yielded gas-phase products such as NO, NO2, N2O4, N2O, and HONO. While the correlation between semiconductor properties of the metal oxide and the heterogeneous photochemical rate constant (j) is not direct, the semiconductor properties were found to play a role in the formation of relatively high proportions of greenhouse gas nitrous oxide (N2O).

Umbilical cord blood levels of cortisol and dehydroepiandrosterone sulfate in preterm prelabor rupture of membrane pregnancies complicated by the presence of histological chorioamnionitis.

OBJECTIVE: The main aim of this study was to determine the levels of cortisol and dehydroepiandrosterone sulfate (DHEA-S) and the cortisol/DHEA-S ratio in the umbilical cord blood according to the presence of histological chorioamnionitis and fetal inflammatory response in pregnancies complicated by prelabor rupture of membranes at fewer than 34 gestational weeks. METHODS: Seventy-two women with singleton pregnancies complicated by preterm prelabor rupture of membranes between gestational ages 24+0 and 33+6 weeks were included in the study. The sample of blood was obtained from the umbilical cord after delivery of the newborn. The umbilical cord blood cortisol and DHEA-S levels were evaluated using commercial immunoassay kits. A cortisol/DHEA-S ratio was calculated. RESULTS: The presence of histological chorioamnionitis was not associated with higher median levels of cortisol (32.1 nmol/L vs. 33.0 nmol/L; p = 0.53), DHEA-S (2.6 µmol/L vs. 2.5 µmol/L; p = 0.83), or cortisol/DHEA-S ratio (19.5 vs. 18.7;p = 0.90). Higher median levels of DHEA-S (3.1 µmol/L vs. 2.3 µmol/L; p = 0.03) but not cortisol (91.0 nmol/L vs. 32.0 nmol/L; p = 0.06) or cortisol/DHEA-S ratio (24.5 vs. 18.7; p = 0.46) were observed when fetal inflammatory response was present. CONCLUSIONS: The presence of fetal inflammatory response but not the presence of histological chorioamnionitis per se was associated with increased DHEA-S levels in the umbilical cord blood.

Soluble Toll-like receptor 1 family members in the amniotic fluid of women with preterm prelabor rupture of the membranes.

OBJECTIVE: To determine soluble Toll-like receptor (sTLR) 1, sTLR2 and sTLR6 concentrations in amniotic fluid (AF) of women with preterm prelabor rupture of membranes (PPROM) and if there is an association with microbial invasion of the amniotic cavity and histological chorioamnionitis (HCA). METHODS: Cross-sectional study was performed. Forty-two women with singleton PPROM pregnancies at a gestational age between 24 + 0 and 36 + 6 weeks were included in the study (twenty-two women with presence of both microbial invasion of the amniotic cavity and HCA, and 20 women without microbial invasion of the amniotic cavity and HCA). Amniocenteses were performed, and the concentrations of sTLRs were determined by sandwich enzyme-linked immunosorbent assays. RESULTS: Women with microbial invasions of the amniotic cavity and HCA (n = 22) had significantly higher median sTLR1, sTLR2 and sTLR6 levels than those without (n = 20). (20.4 ng/mL vs. 0.44 ng/mL; p < 0.0001, 577.6 ng/mL vs. 60.7 ng/mL; p < 0.0001 and 0.44 ng/mL vs. 0.26 ng/mL; p = 0.02, respectively). CONCLUSIONS: Women with microbial invasion of the amniotic cavity and HCA had higher AF sTLR1, 2 and 6 levels.