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A robust and compact blue optical frequency reference within blue region was designed. A 40‐mW tellurium‐stabilized single‐frequency blue diode laser in external cavity was designed with an absorption spectroscopy method based on tellurium molecular transitions. Furthermore, the uncertainty of the frequency stabilization can be pushed to 2 × 10−9 at a 10‐s integration time. In addition, the correspondence frequency instability was 1.3 MHz when the laser wavelength was 445.75 nm. This study indicates that high‐stability frequency reference within the blue region can be achieved with an external cavity diode laser as opposed to the diode‐pumped frequency‐doubled solid‐state laser. [ABSTRACT FROM AUTHOR]

We designed a single‐frequency green laser system that can deliver a 60‐mW frequency‐tunable single‐longitudinal‐mode laser beam, having a 6.5 MHz linewidth at around 519 nm. An external cavity diode laser can provide a wavelength‐tunable single frequency laser beam, but its output power is limited. Therefore, an injection‐locked laser was designed with a Fabry–Perot type green InGaN laser diode in an external Littrow‐type cavity as the master laser and another laser diode of the same model as the slave laser. Injection locking can effectively enhance the output power and narrow the linewidth of the master laser. We found that the injection locking occurred at longitudinal mode matching between the master laser and slave laser diodes, which is located at a specific frequency for a periodical applied current. The side peaks of the injection locking due to the transverse mode mismatching were recorded and analyzed. [ABSTRACT FROM AUTHOR]

The 2 1Π state of NaH has been observed up to the last bound vibrational level using pulsed optical-optical double resonance fluorescence depletion spectroscopy. A total of 20 rovibrational energy levels (v = 2–4 and J = 1–9) were assigned to this electronic state by means of comparing the successive rovibrational spectra to the eigenvalues of the ab initio potential energy curve. The decrease of background fluorescence near the atomic asymptotic limit Na(3d) + H(1s) is an indication of reaching the dissociation limit of the NaH 2 1Π state. Unobserved rovibrational levels (v = 0 and 1) are due to poor Franck-Condon overlap of 2 1Π ← A1Σ+ transition within the accessible rovibrational levels of intermediate A1Σ+ state of this work. [ABSTRACT FROM AUTHOR]

The nd 1Δg (n=6, 7, and 8) Rydberg states of Na2 correlating with the asymptotic limits of Na(3s)+Na(nd) have been observed using high-resolution cw optical-optical double resonance spectroscopy corresponding to the rovibrational transitions X 1Σg+(v″,J″)+hνpump→B 1Πu(v′,J′)+hνprobe→nd 1Δg(v,J). Totals of 104, 83, and 45 identified rovibrational e/f-parity levels in the ranges of v=0–11, 11≤J≤83; v=0–10, 11≤J≤83; and v=0–10, 11≤J≤65, have been assigned to the 6d 1Δg, 7d 1Δg, and 8d 1Δg states, respectively. Using the observed quantum levels, molecular constants were determined from the Dunham fits of the e-parity levels and the Rydberg–Klein–Rees potential curves were constructed for the nd 1Δg(n=6–8) states. The characteristics of the estimated Λ-doubling splitting constants (q0, qv, and μ) with n(=5–8) of the nd 1Δg series have been explored. Detailed investigations reveal that the nd 1Δg(n=6–8) states involve L uncoupling from the internuclear axis and each of these states is affected by an asymmetric perturbation caused by the up and down adjacent states. The rotational-branch intensity and position anomalies in the observed spectra of the nd 1Δg series (n=5–8) of Na2 lead to the conclusion that due to the effects of the L-uncoupling perturbations, the same l complexes approaching the same ion-core limits result in the same l-mixing processes which lead to the formation of the supercomplexes due to the anisotropy of the molecular-ion [Na2+(3s)] field. This would open up opportunities to study the effects of L uncoupling and perturbations in the nd series and high Rydberg states of other alkali dimers. [ABSTRACT FROM AUTHOR]

The 1 3Δg state of Na2 has been studied extensively by both filtered fluorescence and ionization detection and analyzed by both Dunham-type expansion and near-dissociation expansion (NDE) models in the analysis. Our observations have covered 99.998% of the potential well depth with the outermost Rydberg–Klein–Rees (RKR) turning point at 28.02 Å. NDE analysis gives Te=28 032.468 (±0.021) cm-1, De=7162.436 (±0.021) cm-1, and Re=3.463 81 (±0.000 28) Å. Significant long-range behavior in the near dissociation levels has been observed. Fitting of the RKR turning points gives the long-range coefficients C5=1.388 (±0.031)×106 cm-1 Å5 and C6=0.4008 (±0.0046)×108 cm-1 Å6. These newly observed results show reasonable agreement with recent theoretical calculations. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

This paper critically surveys the best available spectroscopic data for the two lowest electronic states (X 1Σ+g and a 3Σ+u) of K2. Since both states are known up to dissociation, they can be used to determine Coulomb and exchange contributions to the intermediate and long range interaction potentials. The multipolar expansion representation of the Coulomb (dispersion) energy at long range (-ΣnCnR-n) and the exponential representation of the exchange energy (Ae-αR) as well as a variety of theoretical calculations are compared with these empirical results. Finally, dissociation energy values are discussed and improved dissociation energies for the X 1Σ+g (De=4449.1±1.0 cm-1) and the a 3Σ+u state (De=252.9±1.1 cm-1) proposed. © 1994 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The 4 1Σ+g ‘‘shelf’’ state of Na2 was extensively investigated using optical–optical double resonance spectroscopy and an ultrasensitive ionization detector. A total of 179 vibrational levels-(0≤v≤127 are from previous work by using filter-photomultiplier tube fluorescence detection) were observed in this state, which covered more than 99.8% of the well depth. The Rydberg–Klein–Rees (RKR) potential energy curve was constructed with maximum outer turning point R178+ = 17.60 Å. The comparison of the long range portion of the RKR potential energy curve and the potential curve calculated from V(R)=ΣnCn/Rn is discussed. Avoided crossings around the shelf with the 3 1Σ+g state and near dissociation with the 5 1Σ+g state are also discussed. [ABSTRACT FROM AUTHOR]

Using optical–optical double resonance and an ultrasensitive ionization detector, we have been able to extensively study a wide range of internuclear distances for the 5 1Σ+g state of Na2. Using a combination of spectroscopic data and the ab initio calculations, we have constructed a hybrid potential which has an outer well at shelf region. For this hybrid potential, there are 54 vibrational levels in the inner well (which all have been observed in this work) and 12 vibrational levels in the outer well (of which only the last level has been observed in this work). Above the potential barrier, 78 additional vibrational levels have been observed in this work. These spectroscopic data represent about 99.8% of the potential well depth. [ABSTRACT FROM AUTHOR]

The 3 1Σ+g state of Na2 has been extensively studied using an optical–optical double resonance technique and a shielded cylindrical space-charge-limited ionization detector. A wide range of vibrational quantum numbers 0≤v≤141 was observed which covered over 99.9% of the potential well depth. A ‘‘shelf’’ on the potential energy curve was found near v=23. A hybrid potential was constructed based on the Rydberg–Klein–Rees (RKR) potential curve and a local inverse perturbation approach (IPA) for the shelf region. For this potential, there is a shallow second local minimum ∼5 cm-1 in depth at the shelf region. The long range energy also compares well with long range theory. [ABSTRACT FROM AUTHOR]

All quasibound vibrational energy levels v=27 and 28 of the Na2 3 1Πg state were accessed by using optical–optical double resonance and detected with a shielded ionization detector. The line broadening due to the tunneling effect was observed to be larger than 1 cm-1 at the rovibrational level v=28, J=31. The potential curve has been determined by the Rydberg–Klein–Rees method and modified using Jeung’s calculation for the large distance barrier and comparison of the calculated and the measured line widths. The barrier height was found to be ∼126 cm-1 above its asymptotic limit (3s+4p) at 5.98 Å. There also exists an unobserved shallow outer well with depth ∼35 cm-1 at 9.5 Å according to our modification of Jeung’s calculated potential. One way to possibly probe this outer well is also discussed. [ABSTRACT FROM AUTHOR]

BackgroundEvidence-based medicine has been regarded as a prerequisite for ensuring health care quality. The increase in health care professionals’ adoption of web-based medical information and the lack of awareness of alternative access to evidence-based online resources suggest the need for an investigation of their information-searching behaviors of using evidence-based online medical databases. ObjectiveThe main purposes of this study were to (1) modify and validate the internet-specific epistemic beliefs in medicine (ISEBM) questionnaire and (2) explore the associations between health care professionals’ demographics, ISEBM, and intention to use evidence-based online medical databases for clinical practice. MethodsHealth care professionals in a university-affiliated teaching hospital were surveyed using the ISEBM questionnaire. The partial least squares-structural equation modeling was conducted to analyze the reliability and validity of ISEBM. Furthermore, the structural model was analyzed to examine the possible linkages between health professionals’ demographics, ISEBM, and intention to utilize the evidence-based online medical databases for clinical practice. ResultsA total of 273 health care professionals with clinical working experience were surveyed. The results of the measurement model analysis indicated that all items had significant loadings ranging from 0.71 to 0.92 with satisfactory composite reliability values ranging from 0.87 to 0.94 and average variance explained values ranging from 0.70 to 0.84. The results of the structural relationship analysis revealed that the source of internet-based medical knowledge (path coefficient –0.26, P=.01) and justification of internet-based knowing in medicine (path coefficient 0.21, P=.001) were correlated with the intention to use evidence-based online medical databases. However, certainty and simplicity of internet-based medical knowledge were not. In addition, gender (path coefficient 0.12, P=.04) and academic degree (path coefficient 0.15, P=.004) were associated with intention to use evidence-based online medical databases for clinical practice. ConclusionsAdvancing health care professionals’ ISEBM regarding source and justification may encourage them to retrieve valid medical information through evidence-based medical databases. Moreover, providing support for specific health care professionals (ie, females, without a master’s degree) may promote their intention to use certain databases for clinical practice.

Vibrational levels (v = 6–42) of the NaH C1Σ+ state including the inner and outer wells and the near-dissociation region were observed by pulsed optical-optical double resonance fluorescence depletion spectroscopy. The absolute vibrational quantum number is identified by comparing the vibrational energy difference of this experiment with the ab initio calculations. The outer well with v up to 34 is analyzed using the Dunham expansion and a Rydberg-Klein-Rees (RKR) potential energy curve is constructed. A hybrid double-well potential combined with the RKR potential, the ab initio calculation, and a long-range potential is able to describe the whole NaH C1Σ+ state including the higher vibrational levels (v = 35–42). The dissociation energy of the NaH C1Σ+ state is determined to be De(C) = 6595.10 ± 5 cm−1 and then the dissociation energy of the NaH ground state De(X) = 15 807.87 ± 5 cm−1 can be derived. [ABSTRACT FROM AUTHOR]

Huai-Shan-Yao (Chinese yam; Rhizome Dioscoreae) is a common food in china. In the present study, we evaluated the protective effects of the crude extract of Huai-Shan-Yao on acute kidney and liver injuries in rats induced by ethanol. Results of pharmacological, biochemical and pathologic observations all showed that rats treated with the extract of Huai-Shan-Yao had decreased damage in renal tubules as well as decreased inflammation in the central vein and necrosis in the liver tissue. [ABSTRACT FROM AUTHOR]

A shielded cylindrical space-charge-limited diode ionization detector with high sensitivity and high resolution has been constructed to detect ionization in metal vapors, e.g., multiphoton ionization in the sodium atom and collisional associative ionization in the Rydberg states of the sodium dimer. The diode design and construction and measurements of its characteristics are described. Using this diode detector, a wide variety of high resolution spectroscopy can be obtained using techniques such as two-photon excitation, optical–optical double resonance, perturbation-facilitated optical–optical double resonance, and all-optical triple resonance. [ABSTRACT FROM AUTHOR]

In this study, the B 1 Π excited state of NaH has been experimentally studied for the first time. Pulsed laser-induced fluorescence excitation spectroscopy was used to investigate the B 1 Π electronic state of NaH. A total of 48 ro-vibronic transitions were observed, including within the B - X (0-0) and B - X (0-1) transition bands. Only one B -state vibrational level was identified, and a series of PQR lines, with eight e -parity and eight f -parity sublevels ( v ' = 0, J ' = 1-8), were assigned. The level assignment was supported by a comparison of the experimental line positions with the ab initio calculations, the dispersed laser-induced fluorescence spectrum of the NaH B 1 Π → X 1 ∑ + emission, and the V-type optical-optical double resonance spectra. The Dunham-type coefficients, the mean internuclear distance, the harmonic vibrational frequency ω, and the dissociation energies D 0 and D e of the B 1 Π state were determined., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

The effect of polarization on the ladder-type electromagnetically induced transparency (EIT) spectra of 133 Cs atoms at room temperature for the transitions 6 2 P 1/2 -6 2 P 3/2 -11 2 S 1/2 is experimentally studied. The entire spectra with additional peaks arising from the Doppler effect are observed. As the relative angle between the probe's and coupling's plane of polarization arranges at 0 ° , 45 ° , and 90 ° , the peak height ratio of 44'3" to 44'4" increases by more than 7 times with corresponding values of 0.19, 0.69, and 1.4. Meanwhile, that of 45'4" to 44'4" are found to be 0.61, 0.87, and 1.23 (doubled), respectively. A theoretical model built to explain the experimental results with the considerations of optical pumping effect, two-photon transition probability, dephasing rate, and integration all over the velocity distribution. The simulation and experimental results are well-agreed.

Stimulated emission pumping with fluorescence depletion spectroscopy is used to determine the NaD X 1 Σ + ground-state dissociation energy and its isotopic shift. A total of 230 rovibrational levels in the range 9 ≤ v″ ≤ 29 and 1 ≤ J″ ≤ 11 are observed, where v″ = 29 is about 50 cm -1 below the dissociation limit. Analysis of the highest five vibrational levels yields the dissociation energy D e = 15 822 ± 5 cm -1 with a vibrational quantum number at dissociation v D = 31.2 ± 0.1. The energy difference in the well depth of this isotopologue with respect to that of NaH is δD e = D e (NaH) - D e (NaD) = -7 cm -1 . A new set of Dunham coefficients is derived to fit all the observed energy levels to within the experimental uncertainty.

Background: The active components of Gardenia (Gardenia jasminoides Ellis, GJ) exhibit a hypoglycemic effect by improving insulin secretion and lowering plasma lipids. In the present study, we fed a water extract of gardenia to steroid-induced insulin-resistant (SIIR) rats and observed changes in signaling proteins in order to elucidate the mechanisms of the insulin-sensitizing effect of GJ and evaluate its possibility as an insulin-sensitizing agent., Methods: Normal Wistar rats were randomly divided into a control group (i.e., saline) and experimental groups (GJ 100 and 200 mg/kg). Blood samples were taken at 0, 30, and 60 min for plasma glucose assay in order to determine the optimal dose to induce the hypoglycemic effect. SIIR rats were then randomly divided into a control group (i.e., saline) and an experimental group (optimal dose of gardenia extract) to observe the insulin-sensitizing effect of the extract. Finally, western blot analysis was performed to detect intracellular signaling proteins to elucidate the mechanisms of the insulin-sensitization effect of GJ., Results: The normal Wistar rats in the GJ 200 mg/kg group exhibited significant hypoglycemic activity. Meanwhile, the SIIR rats had higher plasma glucose levels than normal rats. There was no obvious change in insulin level, but the insulin sensitivity index and homeostasis model assessment index were significantly elevated. Meanwhile, a significant hypoglycemic effect was observed with GJ 200 mg/kg. In addition, intracellular signaling proteins including insulin receptor substrate-1 (IRS-1) and peroxisome proliferator-activated receptor (PPARγ) were elevated in muscle cells., Conclusions: The optimal dose of GJ aqueous extract of 200 mg/kg exerts a PPARγ-activating hypoglycemic effect and improves insulin resistance in SIIR rats. Therefore, it is a potential insulin-sensitizing agent in type 2 diabetes mellitus with insulin resistance.

Aims. To evaluate the efficacy of rosiglitazone (TZD) and electroacupuncture (EA) combined therapy as a treatment for type 2 diabetes mellitus (T2DM) patients by randomized single-blind placebo controlled clinical trial. Methods. A total of 31 newly diagnostic T2DM patients, who fulfilled the study's eligibility criteria, were recruited. The individuals were randomly assigned into two groups, the control group (TZD, N = 15) and the experimental group (TZD + EA, N = 16). Changes in their plasma free fatty acid (FFA), glucose, and insulin levels, together with their homeostasis model assessment (HOMA) indices, were statistically compared before and after treatment. Hypoglycemic activity (%) was also compared between these two groups. Results. There was no significant difference in hypoglycemic activity between the TZD and TZD + EA group. The effectiveness of the combined therapy seems to derive from an improvement in insulin resistance and a significant lowering of the secreted insulin rather than the effect of TZD alone on T2DM. The combined treatment had no significant adverse effects. A lower plasma FFA concentration is likely to be the mechanism that causes this effect. Conclusion. This combined therapy seems to suppress endogenous insulin secretion by improving insulin resistance via a mechanism involving a reduction in plasma FFA. This trial is registered with ClinicalTrials.gov NCT01577095.

In our previous research, Cordyceps militaris (CM) had a hypoglycemic effect in normal rats. In this study we wanted to elucidate whether CM also had an effect on diabetic rats. Twelve rats with streptozotocin-induced diabetes were separated randomly into 2 groups. First, aqueous extracts of CM 10 mg/kg (CM group) or saline (control group) was fed to the rats; then the plasma glucose levels were assayed. Second, the signaling proteins IRS-1 and GLUT-4 collected from the muscle were detected. Finally, another 2 groups of rats were injected with atropine 0.1 mg/kg intraperitoneally just before the CM/saline feeding, and the assays mentioned above were repeated. Blood glucose decreased 7.2% in the CM group but only 1.5% in the control group (P < 0.05). The IRS-1 signal was 2.9-fold higher than actin in the CM group but only 0.8-fold higher in the control group (P < 0.005). In GLUT-4 signal, the difference was 1.7- vs. 0.6-fold, respectively, compared with actin (P < 0.05). However, atropine injection made CM-induced hypoglycemia or elevation of IRS-1 and GLUT-4 not significant. In conclusion, CM had a hypoglycemic effect in diabetic rats and atropine blocked it. Therefore, the cholinergic activation also was considered to be involved in the hypoglycemic effect of CM in rats with streptozotocin-induced diabetes.

The probability of two-photon transition (TPT) under a control field to inhibit the quantum interference and enhance the nonlinear optical cross section is observed. Essentially, this is a V-type electromagnetically induced transparency (EIT) with TPT instead of one photon transition. Numerical simulation based on solving the steady state density matrix can qualitatively fit the experimental data. A model of double-Lorentzian profile is used to fit the observed spectrum and give the de-convolution information of the inhibition of TPT spectrum due to EIT and enhancement on the wings of TPT. The frequency shift of the inhibit center is linear to the intensity of the control field (one-photon) and quadratic to the intensity of probe field (two-photon). Under the control field, a factor of 10 enhancements on the wings of the TPT is observed.

The dissociation energy of the ground state of NaH was determined by analyzing the observed near dissociation rovibrational levels. These levels were reached by stimulated emission pumping and fluorescence depletion spectroscopy. A total of 114 rovibrational levels in the ranges 9

We present detailed investigations of our previously reported observations of the 3(1)Delta(g) and 4(1)Delta(g) Rydberg states having separated-atom limits of Na(3s) + Na(4d) and Na(3s) + Na(4f), respectively, of Na(2) using high-resolution cw optical-optical double resonance spectroscopic measurements and analyzing the assigned rovibrational energy levels both by the individual linear fit method and the Dunham polynomial fit method. We have sorted out e/f-parity observed energy levels, and then from the Dunham polynomial fits of the e-parity levels, we have derived molecular constants and constructed Rydberg-Klein-Rees potentials of the 3(1)Delta(g) and 4(1)Delta(g) states, which appear to be twin states with an avoided crossing at R(c) = 4.10 A and a splitting of DeltaE(c) = 94 cm(-1). The potentials are in good agreement with the ab initio calculations and linear fit results. The Lambda-doubling splittings and the (f-d) l-mixing are investigated. A detailed discussion is focused on the adiabatic interaction of the perturbed molecular wave functions/states causing mutual amplitude/intensity sharing giving rise to avoided crossing between the 3(1)Delta(g) and 4(1)Delta(g) states.

The 71Pig Rydberg state of Na2 correlating with the separated atom limit Na(3s) + Na(5p) has been observed using high-resolution cw optical-optical double resonance spectroscopy. A total of 104 identified rovibrational levels in the range v = 0-12 and 11

The phenomenon of electronic orbital angular momentum L uncoupled from its internuclear axis has been observed in the sodium dimer using high-resolution cw optical-optical double-resonance spectroscopy. When L uncoupling occurs, the degeneracy of Lambda doubling is removed. In our experiment, the intermediate B (1)Pi(u) state of Na(2) is excited from the thermally populated ground X (1)Sigma(g) (+) state by a single-line Ar(+) laser. Then, a single-mode dye laser is used to probe the Rydberg states from the intermediate state. The signals are detected by monitoring the UV fluorescence from the triplet gerade states back to the a (3)Sigma(u) (+) state via collision energy transfer. Under our experimental resolution, the splitting of Lambda doubling in the 5 (1)Delta(g) state of Na(2) can be measured. A total of 136 rovibronic levels with ef parities have been assigned to the 5 (1)Delta(g) state. The Lambda-splitting constants deduced from these data are q(0)=0.376(90)x10(-4) cm(-1), q(v)=0.114(6)x10(-4) cm(-1), and mu=0.76(33)x10(-8) cm(-1). In general, the Lambda splitting of the Delta states is considerably smaller than that of the Pi states. However, the first-order splitting constants q(0) and q(v) reported here are larger than those in the B (1)Pi(u) state. This is due to the L uncoupling of the Rydberg states.

The doubly excited valence (3p+3p) 2 (1)Delta(g) state of Na(2) is experimentally observed by using optical-optical double resonance spectroscopy. A single line Ar(+) laser (a total of nine lines) was used to pump the sodium dimers from thermally populated ground state X (1)Sigma(g) (+) to the intermediate B (1)Pi(u) state. Then, a single mode Ti:sapphire laser was used to probe the doubly excited 2 (1)Delta(g) state. Violet fluorescence emitted from the highly excited states (mainly 2 (3)Pi(g) or 3 (3)Pi(g) states which are transferred from 2 (1)Delta(g) state via collision) to the a (3)Sigma(u) (+) state was monitored by a filtered photomultiplier tube (PMT). A total of 582 rovibrational levels of 2 (1)Delta(g) state were observed, identified, and assigned to the vibrational and rotational quantum numbers in the range of 0< or =v< or =28 and 11< or =J< or =99, respectively. The absolute vibrational quantum number assignment was verified by comparing the totally resolved fluorescence with the calculated Franck-Condon factors between 2 (1)Delta(g) state and B (1)Pi(u) state. Dunham coefficients and Rydberg-Klein-Rees potential curve were derived from these observed quantum levels. The primary molecular constants of Na(2) 2 (1)Delta(g) state are T(e)=32 416.759(15) cm(-1), omega(e)=124.8484(36) cm(-1), B(e)=0.119 158(3) cm(-1), and R(e)=3.508 20(5) A.

Aim: To study the effect of yam in Taiwan, which is a commonly used Chinese medicine, on hepato-nephro-toxicity in rats., Methods: Crude water extract of yam (Dioscorea alata L), was used to treat rats with an acute toxicity induced by acetaminophen (APAP) challenge., Results: The pharmacological and biochemical studies showed the extract of yam had the effect of kidney secureness and liver fortification (P < 0.01). The pathologic sections showed good improvements in renal tubular degranulation changes, necrosis and disintegration. The extract of yam also possessed a good protection against the inflammation of central vein and necrosis of liver tissue., Conclusion: The liver and kidneys are originated from the same source. Pathologically, deficiency of the life essence in the kidney may lead to the blood deficiency in the liver. The results showed that the yam could prevent the damages of the liver and kidneys, thus preserving their functions. This could b e the reason why the yam was commonly used in traditional Chinese medicine, as seen in Liuwei Dihuang Wan be used in the case of deficiency of liver-yin and kidney-yin.