Rovibrational Energies of 13C16O2 Determined with Kilohertz Accuracy.

Accurate spectroscopic data of carbon dioxide are widely used in many important applications, such as carbon monitoring missions. Here, we present comb-locked cavity ring-down saturation spectroscopy of the second most abundant isotopologue of CO2, 13C16O2. We determined the positions of 88 lines in three vibrational bands in the 1.6 µm region, 30011e/30012e/30013e-00001e, with an accuracy of a few kHz. Based on the analysis of combination differences, we obtained for the first time the ground-state rotational energies with kHz accuracy. We also provide a set of hybrid line positions for 150 13C16O2 transitions. The rotational energies (J < 50) in the 30013e vibrational state can be fitted by a set of rotational and centrifugal constants with deviations within a few kHz, indicating that the 30013e state is free of perturbations. These precise isotopic line positions will be utilized to improve the Hamiltonian model and quantitative remote sensing of carbon dioxide. Moreover, they will help to track changes in the carbon source and sink through isotopic analysis.

Fano-like Resonance due to Interference with Distant Transitions.

Narrow optical resonances of atoms or molecules have immense significance in various precision measurements, such as testing fundamental physics and the generation of primary frequency standards. In these studies, accurate transition centers derived from fitting the measured spectra are demanded, which critically rely on the knowledge of spectral line profiles. Here, we propose a new mechanism of Fano-like resonance induced by distant discrete levels and experimentally verify it with Doppler-free spectroscopy of vibration-rotational transitions of CO_{2}. The observed spectrum has an asymmetric profile and its amplitude increases quadratically with the probe laser power. Our results facilitate a broad range of topics based on narrow transitions.

Cavity-enhanced saturated absorption spectroscopy of the (30012) - (00001) band of 12C16O2.

The (30012) ← (00001) band of 12C16O2 in the 1.6 µm region is used for satellite observation of carbon dioxide in the Earth's atmosphere. Here, we report a Doppler-free spectroscopy study of this band with comb-locked wavelength-modulated cavity-enhanced absorption spectroscopy. Frequencies of 18 transitions with the rotational quantum numbers up to 42 were determined with sub-kHz accuracy, corresponding to a fractional uncertainty at the 10-12 level. With this precision, we revealed an anomalous decrease of the line shift and an increase of the line broadening for the Lamb dips of CO2 in the low-pressure regime compared to values obtained from Doppler-limited spectra at higher pressures.

Cavity ring-down spectroscopy based on a comb-locked optical parametric oscillator source.

Spectroscopy of molecules in the mid-infrared (MIR) region has important applications in various fields, such as astronomical observation, environmental detection, and fundamental physics. However, compared to that in the near-infrared, precision spectroscopy in the MIR is often limited by the light source and has not shown full potential in sensitivity. Here we report a cavity ring-down spectroscopy system using a tunable narrow-linewidth optical parametric oscillator, which fulfills the requirement of high sensitivity and high precision in the MIR region. The Lamb-dip spectrum of the N2O molecule at 2.7 µm was measured as a demonstration of spectroscopy in the MIR with kilohertz accuracy.

Dispersion-like lineshape observed in cavity-enhanced saturation spectroscopy of HD at 1.4 µm.

Precision measurement of ro-vibrational transitions in the electronic ground state of the hydrogen molecule can be used to test quantum electrodynamics and also to determine the dimensionless proton-to-electron mass ratio. Saturation spectroscopy of the 2-0 overtone transitions of hydrogen deuterium (HD) were measured with three cavity-enhanced spectroscopy methods. With a sensitivity at the 10-13cm-1 level, we revealed a dispersion-like lineshape instead of a conventional Lamb "dip," which explains the significant discrepancy among previous independent measurements. The spectra can be fit well by using the Fano profile. Centers of R(1) and R(3) lines were determined as 217 105 182 111 (19)stat(240)syskHz and 220 704 305 234 (20)stat(240)syskHz, respectively.

Seeded optical parametric oscillator light source for precision spectroscopy.

Precision spectroscopy of fundamental bands of molecules in the mid-infrared (MIR) region is of great interest in applications of trace detection and testing fundamental physics, where high-power and narrow-linewidth MIR lasers are needed. By using a frequency-stabilized near-infrared laser as a seed of the signal light of a continuous-wave optical parametric oscillator, we established a broadly tunable MIR light source that has an output power of several hundred milliwatts and a linewidth of a few tens of kilohertz. The MIR laser frequency drift was reduced to below 1 kHz by using an optical frequency comb to stabilize the frequency of the 1064 nm pumping laser. The performance of the light source was investigated and tested by measuring the saturated absorption spectroscopy of a few molecular transitions at 3.3 µm.

[Primary development of visual uroflow scale].

OBJECTIVE: To develop the visual uroflow scale (VUS), analyze the relationship of VUS score and index of free uroflowmetry, assess urination function preliminarily and improve the work efficiency in the clinic. METHODS: Male lower urinary tract symptoms (LUTS) patients, who attended the Department of Urology in Peking University People's Hospital from March 2016 to March 2017, were assessed for their urination function according to the Visual Uroflow Scale without help from clinicians before undertaking a free uroflowmetry test. And afterwards, a free uroflowmetry was undertaken, and variables including maximal flow rate (Qmax), the average flow rate (Qave) and voiding volume (VV) was obtained. During the study, 124 cases were collected and 53 cases met the inclusion and exclusion criteria and were included in the study cohort. The Spearman correlation analysis was used for analyzing the correlation of VUS scores with free uroflowmetry variables and age. The validity of VUS was evaluated. RESULTS: Most of the patients could choose the very figure matched with self-condition by first instinct without any help from the clinician. The data were analyzed by Spearman correlation analysis. In the present study, voiding time was positively correlated with the VUS score (correlation coefficient, 0.62, P < 0.05). In the present cohort, the patients chose the third and fourth figures to take longer time to urinate, implying worse LUTS situation. Flow time and VUS scores were positively correlated (correlation coefficient, 0.61, P < 0.05). The patients with higher VUS scores would spend more time on urinate, no matter how long urinary hesitation was. Both Qmax and Qave were negatively correlated with the VUS score (correlation coefficient －0.54, －0.62, P < 0.05). The study illustrated that the VUS score suggested that the Qmax basically and further reflected the urination function. And its relationship to age revealed the decreased urination function of aging male, which had reached a consensus. CONCLUSION: Development of VUS has helped the clinician assess the urination function preliminarily at the first time. Patients are assessed for a VUS score before getting surgery or receiving the drug for treatment, and can be re-assessed after. The VUS score can provide an objective quantitative basis to evaluate the treatment efficacy. In addition, considering that it is convenient, timesaving and easy to understand, the VUS is available for follow-up.

Frequency metrology of molecules in the near-infrared by NICE-OHMS.

Noise-immune cavity enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) is extremely sensitive in detecting weak absorption. However, the use of NICE-OHMS for metrology study was also hindered by its sensitivity to influence from various experimental conditions such as the residual amplitude modulation. Here we demonstrate to use NICE-OHMS for precision measurements of Lamb-dip spectra of molecules. After a dedicated investigation of the systematic uncertainties in the NICE-OHMS measurement, the transition frequency of a ro-vibrational line of C2H2 near 789 nm was determined to be 379 639 280 915.3±1.2 kHz (fractional uncertainty 3.2 × 10-12), agreeing well with, but more accurate than, the value determined from previous cavity ring-down spectroscopy measurements. The study indicates the possibility to implement the very sensitive NICE-OHMS method for frequency metrology of molecules, or a molecular clock, in the near-infrared.

Comb-locked cavity ring-down spectroscopy with variable temperature.

Temperature dependence of molecular absorption line shape is important information for spectroscopic studies and applications. In this work, we report a comb-locked cavity ring-down spectrometer employing a cryogenic cooler to perform absorption spectroscopy measurements at temperatures between 40 K and 300 K. As a demonstration, we recorded the spectrum of the R(0) line in the (2-0) band of HD at 46 K. The temperature was also confirmed by the Doppler width of the HD line. Spectra of CH4 near 1.394 µm were also recorded in a wide temperature range of 70-300 K. Lower-state energies of methane lines were analyzed by fitting these spectra, which can be directly compared with the HITRAN and TheoReTS databases. Considerable deviations were observed, indicating the need to investigate the assignments of the methane lines in this region.

[Analysis of urodynamic study of female outpatients with lower urinary tract symptoms and follow-up of the patients with detrusor underactive].

OBJECTIVE: To find out the prevalence of lower urinary tract symptoms (LUTS) and analyze the characteristics of the urodynamics diagnosis in female outpatients. To study the natural history of detrusor underactive (DU) by the followed up. METHODS: A retrospective study of the female LUTS outpatients in Peking University People's Hospital from Jan. 2005 to Dec. 2015 was performed. The basic information and the urodynamic results of a total of 656 female outpatients were collected. The distribution of storage symptoms, voiding symptoms, complications and urodynamic diagnosis were analyzed. The symptoms and urodynamic results were compared among the groups, which were divided according to age, urodynamic diagnosis and diabetes mellitus. A follow-up of 163 female DU outpatients was performed, including the treatments and the American Urological Association symptoms scores (AUAss). RESULTS: Frequency (25.03%) is the most common symptom in female outpatients, followed by stress urinary incontinence (20.04%), urgency (19.97%), and difficulty of voiding (17.32%). Stress urinary incontinence (SUI) accounted for the first (36.04%) of the whole outpatients, followed by the DU (24.08%), and bladder outlet obstruction (17.58%). The patients aged 51-60 years occupied the peak of almost all the diagnosis. There was a higher proportion of the young female patients than that of the middle and old patients diagnosed with no abnormal after the urodynamic study. The first, strong, urge and maximum bladder capacity were significantly larger in DU patients with diabetes than without diabetes. Follow-up results of the DU patients showed there was no significantly difference of the AUAss scores in both the two groups before and after the follow-up, but the quality of life decreased significantly. CONCLUSION: Female LUTS outpatients showed a main complaint of storage symptoms. SUI ranked the first in female patients with LUTS. With the increase of age, bladder sensation and detrusor function decrease. In elderly patients, DU became the first ranked disease instead of SUI. Diabetes can affect the sensory function of bladder in patients with DU, and then increase the difficulty of voiding. The patients with DU, absent from treatment, experienced a lower quality of life.

Toward a Determination of the Proton-Electron Mass Ratio from the Lamb-Dip Measurement of HD.

Precision spectroscopy of the hydrogen molecule is a test ground of quantum electrodynamics (QED), and it may serve for the determination of fundamental constants. Using a comb-locked cavity ring-down spectrometer, for the first time, we observed the Lamb-dip spectrum of the R(1) line in the overtone of hydrogen deuteride (HD). The line position was determined to be 217 105 182.79±0.03_{stat}±0.08_{syst} MHz (δν/ν=4×10^{-10}), which is the most accurate rovibrational transition ever measured in the ground electronic state of molecular hydrogen. Moreover, from calculations including QED effects up to the order m_{e}α^{6}, we obtained predictions for this R(1) line as well as for the HD dissociation energy, which are less accurate but signaling the importance of the complete treatment of nonadiabatic effects. Provided that the theoretical calculation reaches the same accuracy, the present measurement will lead to a determination of the proton-to-electron mass ratio with a precision of 1.3 parts per billion.

Laser Spectroscopy of the Fine-Structure Splitting in the 2

The fine-structure splitting in the 2^{3}P_{J} (J=0, 1, 2) levels of ^{4}He is of great interest for tests of quantum electrodynamics and for the determination of the fine-structure constant α. The 2^{3}P_{0}-2^{3}P_{2} and 2^{3}P_{1}-2^{3}P_{2} intervals are measured by laser spectroscopy of the ^{3}P_{J}-2^{3}S_{1} transitions at 1083 nm in an atomic beam, and are determined to be 31 908 130.98±0.13 kHz and 2 291 177.56±0.19 kHz, respectively. Compared with calculations, which include terms up to α^{5}Ry, the deviation for the α-sensitive interval 2^{3}P_{0}-2^{3}P_{2} is only 0.22 kHz. It opens the window for further improvement of theoretical predictions and an independent determination of the fine-structure constant α with a precision of 2×10^{-9}.

Measurement of the Frequency of the 2

The 2 ^{3}S-2 ^{3}P transition of ^{4}He was measured by comb-linked laser spectroscopy using a transverse-cooled atomic beam. The centroid frequency was determined to be 276 736 495 600.0(1.4) kHz, with a fractional uncertainty of 5.1×10^{-12}. This value is not only more accurate but also differs by as much as -49.5 kHz (20σ) from the previous result given by [Cancio Pastor et al., Phys. Rev. Lett. 92, 023001 (2004)PRLTAO0031-900710.1103/PhysRevLett.92.023001; Cancio Pastor et al.Phys. Rev. Lett.97, 139903(E) (2006)10.1103/PhysRevLett.97.139903; Cancio Pastor et al.Phys. Rev. Lett.108, 143001 (2012)10.1103/PhysRevLett.108.143001]. In combination with ongoing theoretical calculations, this work may allow the most accurate determination of the nuclear charge radius of helium.

[Comparison and discussion of different surgical methods used to treat vesicovaginal fistulas].

OBJECTIVE: To compare the feasibility and prognosis of different surgical methods used for vesicovaginal fistulas and to explore the value of electrocoagulation treating small ones. METHODS: The medical data of 19 patients who had undertaken transvaginal VVF repairs in Peking University People's Hospital between October 2008 and November 2016 were retrospectively collected. The follow-ups were performed. The patients' age ranged from 31 to 55 years with the median age of 48 years and the history length ranged from 1 month to 24 months with the median length of 3 months. Their fistula situation, surgical methods and prognosis were analyzed and the differences and similarities were compared. RESULTS: Three patients (15.79%) was performed by electrocoagulation, 4 (21.05%) by transvaginal repair, 5 (21.32%) by laparoscopic repair and 7(36.84%) by open operation. Except one patient who rejected urinary catheter and D-J catheters, the rest of the patients discharged with catheters. Twelve patients (63.2%) got full satisfaction with one operation. One of the 3 patients who undertook electrocoagulation repeated the operation for twice and got completely cured within 1 month while the other two undertook the operation once and got dry within 1 month. Three patients who undertook transvaginal repair got dry within 1 month. Two of the 5 patients who undertook laparoscopic repair had readmission for a second operation and the other 3 got dry after operation. Five of the 7 open repair patients got dry while the other 2 attempted other center for treatment. CONCLUSION: Transvaginal repair has been the main surgery procedure for VVF, but it is limited by the location of fistula and the condition of vaginal. For patients not suitable for transvaginal repair, laparoscopic repair and open surgery are feasible. However both laparoscopic repair and open surgery are more invasive. Based on that, electrocoagulation becomes a better choice. In our research, patients with small and high location fistula treated by electrocoagulation got a higher cure rate and bear less surgical trauma. Electrocoagulation used in the treatment of VVF showed advantages of less trauma, less bleeding and better satisfaction. Fistulas with low location were more suitable for transvaginal repair. Complex VVF, especially with narrow ureteral open and ureteral fistulas, were more suitable for open and laparoscopic repair. As for single and small fistula, the electrocoagulation can be the first choice.

[Effect of nicorandil on ventricular arrhythmia in patients with acute ST-segment elevation myocardial infarction underwent emergent percutaneous coronary intervention treatment].

Objective: To investigate the effect of nicorandil on ventricular arrhythmia in patients with acute ST-segment elevation myocardial infarction (STEMI) treated with emergent percutaneous coronary intervention (PCI). Methods: A total of 120 acute STEMI patients treated with emergent PCI in our hospital from January 2015 to June 2016 were randomly divided into control group and experiment group (n=60 each). Patients in both groups received conventional therapy.Patients in experiment group took 10 mg nicorandil orally before PCI and received oral nicorandil treatment (15 mg/d, three times daily) for 3 days.QT disperse(QTd), correct QTd(QTcd) and the occurrence rate of ventricular arrhythmia were compared between two groups. Results: QTd at 6, 24, 48 and 72 hours((70.6±4.4), (67.2±5.3), (55.7±8.5), (48.2±8.2) ms, respectively) after PCI was significantly lower in the experiment group than those of control group ((77.1±7.1), (71.3±6.5), (65.1±8.1), (57.2±5.4) ms, all P<0.05). The level of QTd was also significantly lower in the experiment group at 6, 24, 48 and 72 hours((77.5±7.7), (67.7±8.6), (61.2±7.5), (52.9±8.4) ms, respectively) after PCI comared to those of control group ((88.6±8.1), (79.2±7.8), (74.4±7.4), (69.6±8.6) ms, all P<0.05). There was no significant difference in the incidence of reperfusion arrhythmia during PCI procedure between the two groups.The prevalence of the ventricular premature beat in the experiment group (25/60, 41.7%) was significantly lower than in the control group(45/60, 75.0%) within 3 days after PCI(P<0.01), the prevalence of the no sustained ventricular tachycardia and ventricular fibrillation in the experiment group(6/60, 10.0%) was also significantly lower than in the control group (18/60, 30.0%, P<0.01) within 3 days after PCI. Conclusions: Nicorandil use prior and post PCI could decrease the occurrence rate of ventricular arrhythmia in STEMI patients undergoing emergent PCI, and this effect might be related with reduced QTd and QTcd post medication.

[Effect of age on urodynamic parameters of women with urinary incontinence].

OBJECTIVE: To investigate age related changes in urodynamic parameters of women with urinary incontinence. METHODS: From May 2008 to October 2015, a total of 214 patients diagnosed with urinary incontinence in Peking University People's Hospital was involved in this study. Average age was (56.97±10.68) years, ranging from 30 to 82 years, and average history was (8.44±8.85) years, ranging from one month to 50 years. Urodynamic examinations of each patient were taken before operation routinely in Department of Urology, Peking University People's Hospital. The urodynamic study was composed of non-invasive and invasive procedures. Analysis included maximal flow rate (Qmax), average flow rate, time to Qmax, voiding time, detrusor pressure at Qmax, maximal detrusor pressure, voided volume, post-void residual urine volume (PVR), the total capacity of bladder, first-, strong-, and urge-desire to void, cough leak point pressure (CLPP), and Valsalva leak point pressure (VLPP). Patients were divided into four groups according to age, Kolmogorov-Smirnov test and one-way ANOVA were used for data analysis. RESULTS: A total of 214 patients were enrolled in this study. The data of Qmax, average flow rate, voided volume, and total capacity of bladder decreased with statistical significance. The value of residual urine volume and voiding time increased without statistical significance, while the value of maximal detrusor pressure decreased. CONCLUSION: Urodynamic examination data of females with urinary incontinence changes along with the elapse of age, which was mainly observed as age ascends, and the changes in urodynamic parameters of women with urinary incontinence suggest that the value of Qmax, average flow rate, voided volume, and total capacity of bladder decreased significantly, while the value of PVR and the voiding time increased and the value of maximal detrusor pressure decreased.

ß-asarone from Acorus gramineus alleviates depression by modulating MKP-1.

In this study, we investigated the antidepressant effects of hippocampal neuron administration of ß-asarone, a selective mitogen-activated protein kinase phosphatase-1 inhibitor, in a rat model of depression. Our previous studies showed that the extracellular signal-regulated kinase signaling pathway and brain-derived neurotrophic factor expression, which is regulated by extracellular signal-regulated kinase, are key links in the biological mechanism of depression. Mitogen-activated protein kinase phosphatase-1 (MKP-1) is a negative regulatory protein of extracellular signal-regulated kinase signaling pathways. In this study, we explored the regulation of MKP-1 by ß-asarone in producing an antidepressant effect.

Normalization of the single atom counting rate in an atom trap.

The single atom counting rate of a rare isotope and the loading rate of another stable isotope with an abundance over 10 orders of magnitude larger are measured in one atom trap. The linear correlation between the measured counting/loading rates is examined to determine the (84)Kr/(82)Kr and (85)Kr/(83)Kr ratios of a Kr gas sample. Experiments show that the relative uncertainty is reduced to 1.3% when the single atom counting rate of (85)Kr is normalized by the measured (83)Kr loading rate. The measurement of the normalized single atom counting rate can be used to determine extremely low (10(-16)-10(-11)) isotope abundance. This normalization method is robust and can also be applied in other atomic systems.

The 4ν(CH) overtone of 12C2H2: sub-MHz precision spectrum reveals perturbations.

The third CH stretching vibration overtone (4ν(CH)) of the acetylene molecule has been a prototype for intra-molecular dynamics studies. Using a sensitive cavity ring-down spectrometer calibrated with precise atomic transitions, the absolute line frequencies of 50 lines of this band have been determined with sub-MHz accuracy, or relatively 2 × 10(-9). The accuracy is also confirmed by the combination differences between the transitions sharing the same upper level. The improved accuracy, two orders of magnitude better than previous studies, allows us to reveal finer ro-vibrational couplings. Fitting of the rotational energies indicates that the J-dependent interactions take place after J > 7. The precise line positions present useful confinements to the models of the intra-molecular interactions of the acetylene molecule.

Pestalotioid Species Associated with Medicinal Plants in Southwest China and Thailand.

In this paper, a total of 26 pestalotioid isolates associated with different medicinal plants from southwest China and Thailand were studied. Based on morphological examinations and multigene analyses of three gene loci (ITS, tef1-α, and tub2), these 26 isolates represent 17 species distributed in three genera, including seven new species and eight new records. The concatenated three loci tree was used to infer the occurrence of sexual recombination within each pestalotioid genus through the pairwise homoplasy index (PHI) test implemented in SplitsTree. Further, simplifying the description of pestalotioid species is discussed, and a checklist for pestalotioid species associated with medicinal plants worldwide is provided. IMPORTANCE Pestalotioid species are an important fungal group, occurring commonly as plant pathogens, endophytes, and saprophytes. The study of pestalotioid species associated with medicinal plants is significant for agriculture, industry, and pharmaceutical industry but remains poorly studied. In this study, we report 17 pestalotioid species related to medicinal plants based on morphology and molecular analyses. Our study significantly enriches the species richness of pestalotioids and provides a basis for follow-up studies.