A triangular-trapezoidal dual-channel shaping algorithm for resistive anode readout systems and its FPGA implementation.

This paper introduces a novel digital triangular-trapezoidal double-channel shaping algorithm to enhance the counting rate of resistive anode detectors. The algorithm is based on the trapezoidal shaping algorithm and improves it. At the extreme counting rate, the trapezoidal shaping algorithm cannot alleviate the pulse pileup, so the counting rate cannot meet the requirements of a high performance detector. The triangular-trapezoidal double-channel shaping algorithm is introduced in the resistance anode detector, which can replace the trapezoidal shaping filtering algorithm to process the output signal of the resistance anode detector and obtain the single photon position information. This improvement improves the counting rate of the resistor anode detector and reduces the resolution degradation caused by pulse pileup. The algorithm is simulated by System Generator software and implemented on FPGA (field programmable gate array). The triangular-trapezoidal double-channel shaping algorithm presented in this paper plays an important role in reducing electronic noise and pulse pileup. The algorithm is subjected to simulation testing, and it can recognize signals with a minimum pulse interval of 1 µs and counting rate up to 1000 kcps.

Optical Surface-guided Radiation Therapy for Upper and Lower Limb Sarcomas: An Analysis of Setup Errors and Clinical Target Volume-To-Planning Target Volume Margins.

Purpose: To assess the clinical benefits of surface-guided radiation therapy (SGRT) in terms of setup error, positioning time, and clinical target volume-to-planning target volume (CTV-PTV) margin in extremity soft tissue sarcoma (STS). Methods and Materials: Fifty consecutive patients treated with radiation therapy were selected retrospectively. Treatment setup was performed with either laser-based imaging only (control group), or with laser-based and daily optical surface-based imaging (SGRT group). Pretreatment cone beam computed tomography images were acquired daily for the first 3 to 5 fractions and weekly thereafter, with the frequency adjusted as necessary. Translational and rotational errors were collected. CTV-PTV margin was calculated using the formula, 2.5Σ + 0.7σ. Results: Each group consisted of 10 and 15 upper and lower limb STSs, respectively. For patients with upper limb sarcomas, the translation errors were 1.64 ± 1.34 mm, 1.10 ± 1.50 mm, and 1.24 ± 1.45 mm in the SGRT group, and 1.48 ± 3.16 mm, 2.84 ± 2.85 mm, and 3.14 ± 3.29 mm in control group in the left-right, supero-inferior, and antero-posterior directions, respectively. Correspondingly, for patients with lower limb sarcomas, the translation errors were 1.21 ± 1.65 mm, 1.39 ± 1.71 mm, and 1.48 ± 2.10 mm in the SGRT group, and 1.81 ± 2.60 mm, 2.93 ± 3.28 mm, and 3.53 ± 3.75 mm in control group, respectively. The calculated CTV-PTV margins of the SGRT group and control group were 5.0, 3.8, 4.1 versus 5.9, 9.1, 10.1 mm for upper limb sarcomas; and 4.2, 4.7, 5.2 mm versus 6.3, 9.6, and 11.4 mm for lower limb sarcomas in the left-right, supero-inferior, and antero-posterior directions, respectively. Conclusions: Daily optical surface guidance can effectively improve the setup accuracy of extremity STS patients, and safely reduce the required CTV-PTV margins.

Construction and validation of a neovascular glaucoma nomogram in patients with diabetic retinopathy after pars plana vitrectomy.

BACKGROUND: Neovascular glaucoma (NVG) is likely to occur after pars plana vitrectomy (PPV) for diabetic retinopathy (DR) in some patients, thus reducing the expected benefit. Understanding the risk factors for NVG occurrence and building effective risk prediction models are currently required for clinical research. AIM: To develop a visual risk profile model to explore factors influencing DR after surgery. METHODS: We retrospectively selected 151 patients with DR undergoing PPV. The patients were divided into the NVG (NVG occurrence) and No-NVG (No NVG occurrence) groups according to the occurrence of NVG within 6 months after surgery. Independent risk factors for postoperative NVG were screened by logistic regression. A nomogram prediction model was established using R software, and the model's prediction accuracy was verified internally and externally, involving the receiver operator characteristic curve and correction curve. RESULTS: After importing the data into a logistic regression model, we concluded that a posterior capsular defect, preoperative vascular endothelial growth factor ≥ 302.90 pg/mL, glycosylated hemoglobin ≥ 9.05%, aqueous fluid interleukin 6 (IL-6) ≥ 53.27 pg/mL, and aqueous fluid IL-10 ≥ 9.11 pg/mL were independent risk factors for postoperative NVG in patients with DR (P < 0.05). A nomogram model was established based on the aforementioned independent risk factors, and a computer simulation repeated sampling method was used to internally and externally verify the nomogram model. The area under the curve (AUC), sensitivity, and specificity of the model were 0.962 [95% confidence interval (95%CI): 0.932-0.991], 91.5%, and 82.3%, respectively. The AUC, sensitivity, and specificity of the external validation were 0.878 (95%CI: 0.746-0.982), 66.7%, and 95.7%, respectively. CONCLUSION: A nomogram constructed based on the risk factors for postoperative NVG in patients with DR has a high prediction accuracy. This study can help formulate relevant preventive and treatment measures.

Promotion of self-directed learning abilities among Chinese medical students through preparing for career calling and enhancing teaching competencies in medical education: a cross-sectional study.

BACKGROUND: Medical students face a heavy burden as they are tasked with acquiring a vast amount of medical knowledge within a limited time frame. Self-directed learning (SDL) has become crucial for efficient and ongoing learning among medical students. However, effective ways to foster SDL ability among Chinese medical students are lacking, and limited studies have identified factors that impact the SDL ability of medical students. This makes it challenging for educators to develop targeted strategies to improve students' SDL ability. This study aims to assess SDL ability among Chinese medical students and examine the effects of career calling and teaching competencies on SDL ability, as well as the possible mechanisms linking them. METHODS: Data were collected from 3614 respondents (effective response rate = 60.11%) using cross-sectional online questionnaires and analyzed using IBM SPSS Statistics 22.0. The questionnaire comprised a Demographic Characteristics Questionnaire, Self-directed Learning Ability Scale (Cronbach's alpha = 0.962), Teaching Competencies Scale, and Career Calling Scale. RESULTS: The average SDL ability score of Chinese medical students was 3.68 ± 0.56, indicating a moderate level of SDL ability. The six factors of the Self-directed Learning Ability Scale-self-reflection, ability to use learning methods, ability to set study plans, ability to set studying objectives, ability to adjust psychological state, and willpower in studying-accounted for 12.90%, 12.89%, 12.39%, 11.94%, 11.34%, and 8.67% of the variance, respectively. Furthermore, career calling was positively associated with SDL learning ability (ß = 0.295, p < 0.001), and SDL learning ability was positively associated with teaching competencies (ß = 0.191, p < 0.01). Simple slope analysis showed that when the level of teaching competencies was higher, the influence of career calling on SDL ability was stronger. CONCLUSIONS: Chinese medical students' SDL ability has room for improvement. Medical students could strengthen their willpower in studying by setting milestones goals with rewards, which could inspire their motivation for the next goals. Teachers should guide students to learn experience to improve students' reflective ability. Educators play a crucial role in bridging the gap between career calling education and SDL ability enhancement, highlighting the significance of optimal teaching competencies. Colleges should focus on strengthening teachers' sense of career calling and teaching competencies.

Pharmacokinetics of Nifedipine-Sustained Release Tablets in Healthy Subjects After a Single Oral Administration: Bioequivalence Analysis and Food Effects.

We compared newly developed delayed-release oral tablets (test) of 30-mg nifedipine (NFP) with its marketed counterpart (30 mg; reference) in healthy adult Chinese volunteers to assess the former's bioequivalence. This was a randomized, open-label, four-period, crossover trial study including fasting and fed trials. The participants were randomly administered test or reference formulations (1:1 ratio) throughout each period, with a 7-day washout period. In the next session, they were administered the alternate products. Liquid chromatography-tandem mass spectrometry and WinNonlin software were used to evaluate the bioequivalence of the maximum plasma concentration (Cmax ) of NFP and the area under the concentration-time curve (AUC). In total, 46 and 48 people participated in the fasting and postprandial trials. In both groups, the 90% confidence intervals of geometric mean ratios of Cmax , AUC from time zero to time t, and AUC from time zero to infinity were in the equivalence range (80%-125%). When NFP was administered concomitantly with a high-fat meal, time to maximum concentration was approximately twofold earlier, absorption was approximately 4.8% less, and Cmax exhibited a slight change relative to those under fasting conditions. Moreover, no serious adverse events were recorded in the participants. The present findings confirm the bioequivalence of test and reference formulations of NFP tablets under fasting and postprandial conditions.

Investigation of the pharmacological effect and mechanism of mountain-cultivated ginseng and garden ginseng in cardiovascular diseases based on network pharmacology and zebrafish experiments.

Ginseng (Panax ginseng C.A. Mey) is a kind of perennial herb of the Panax genus in the Araliaceae family. The secondary metabolites of mountain-cultivated ginseng (MCG) and garden ginseng (GG) vary greatly due to their different growth environments. To date, the differences in their pharmacological effects on cardiovascular diseases (CVDs) and their clinical applications remain unclear. To distinguish between the components of MCG and GG, ultra-high-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF/MS) was performed. Next, the relationship between the expression of metabolites and the categories of the sample were analyzed using supervised partial least squares discriminant analysis and orthogonal partial least squares discriminant analysis. A network-based pharmacology approach was developed and applied to determine the underlying mechanism of different metabolites in CVD. In the present study, the role of MCG and GG in angiogenesis and their protective effects on damaged blood vessels in a vascular injury model of zebrafish were investigated. Using UPLC-Q-TOF/MS, 11 different metabolites between MCG and GG were identified. In addition, 149 common target genes associated with the metabolites and CVD were obtained; these targets were related to tumor protein P53, proto-oncogene tyrosine-protein kinase Src, human ubiquitin-52 amino acid fusion protein, ubiquitin-40S ribosomal protein S27a, polyubiquitin B, signal transducer and activator of transcription 3, isocitrate dehydrogenase 1, vascular endothelial growth factor A, glycose synthase kinase-3B, and coagulation factor II and were associated with the regulation of the phosphoinositide 3-kinase-Akt signaling pathway, the tumor necrosis factor signaling pathway, and the hypoxia-inducible factor-1 (HIF-1) signaling pathway, which play important roles in the curative effect in CVD treatment. Both types of ginseng can promote the growth of the subintestinal vessel plexus and protect injured intersegmental vessels through the HIF-1α/vascular endothelial growth factor signaling pathway in a dose-dependent manner. In addition, MCG has a stronger impact than GG. This is the first time metabolomics and network pharmacology methods were combined to study the difference between MCG and GG on CVDs, which provides a significant theoretical basis for the clinical treatment of CVD with two kinds of ginseng.

Pharmacokinetics of Esomeprazole Magnesium After Single Oral Doses in Healthy Subjects: Bioequivalence Study and Food Effects.

This study was designed to evaluate the bioequivalence of the newly developed delayed-release oral suspension (test) 40 mg esomeprazole magnesium compared to its marketed counterpart (40 mg; reference) in healthy adult Chinese subjects. We conducted randomized, open-label, two-period, single-dose, two-way crossover trials over a 7-day washout period, comprising a fasting trial and a fed trial. The subjects were administered the test or reference products in a 1:1 ratio at random throughout each period. Then, in the next session, they received the alternate products. Liquid chromatography-tandem mass spectrometry and WinNonlin software were used to assess the bioequivalence of esomeprazole peak plasma concentration (Cmax ) and area under the concentration-time curve (AUC). Overall, 33 subjects participated in the fasting trial and 42 subjects participated in the fed trial. Under both situations, the 90% confidence interval for the ratio of geometric means of Cmax , AUC0-t , and AUC0-∞ were within equivalence ranges (80%-125%). In these trials, no severe adverse events or protocol violations were observed. Moreover, when esomeprazole was administered while fed, the tmax was delayed, and both Cmax and AUC were reduced. The results of this research suggest that the test and reference formulations were bioequivalent under fasting and fed states.

Bioequivalence and Evaluation Parameters Based on the Pharmacodynamics of Miglitol in Healthy Volunteers.

The aim of this study was to explore the bioequivalence of miglitol based on pharmacodynamic properties. The study was performed as a single-dose, randomized, open-label, 3-period, 3-way crossover trial over a 7-day washout period. Forty-eight subjects were randomly assigned into 3 groups: (1) miglitol test formulation/sucrose coadministration, (2) miglitol reference formulation/sucrose coadministration, and (3) sucrose administration alone. Serum glucose concentrations were measured by the hexokinase detection method. The peak serum glucose concentration (Cmax ) and the area under the serum glucose concentration-time curve through 4 hours (AUC0-4h ) were used as the main pharmacodynamic parameters to evaluate bioequivalence. The 90% confidence intervals for the geometric mean ratios of Cmax and AUC0-4h were 94.81%-101.07% and 98.82%-100.72%, respectively, which were all within the bioequivalence range of 80.00%-125.00%. The test and reference formulations of miglitol were pharmacodynamically bioequivalent during the trial.

Parallelized fiber Michelson interferometers with advanced curvature sensitivity plus abated temperature crosstalk.

In this Letter, we proposed a super sensitive optic-fiber curvature sensor with ultra-low temperature crosstalk based on Vernier effect and achieved it experimentally. This sensor composes a pair of parallelized 2CFMIs (2-core-fiber Michelson interferometers) in similar lengths, both of which are involved sensing, but there is a rotation angle between their cross-sections. When the rotation angle approaches 180°, the magnification factor for curvature sensitivity is doubled compared with conventional Vernier effect, while for temperature it is always 1. Therefore, advanced curvature sensitivity and abated temperature crosstalk can be realized simultaneously when demodulating Vernier envelops. The experiment results indicate that the curvature sensitivity of this sensor reached 214.533nm/m-1, and temperature crosstalk was as low as 0.000276m-1/∘C. The fabrication process is extremely flexible and repeatable, and the magnification factor of Vernier effect could be controlled conveniently.

Cytotoxic Activity of Inositol Angelates and Tirucallane-Type Alkaloids from Amoora Dasyclada.

Three new inositol angelate compounds (1-3) and two new tirucallane-type alkaloids (4 and 5) were isolated from the Amoora dasyclada, and their structures were established mainly by means of combination of 1D and 2D nuclear magnetic resonance and HR-ESI-MS. Based on cytotoxicity testing, compounds 4 and 5 exhibited significant cytotoxic activity against human cancer cell line HepG2 with IC50 value at 8.4 and 13.2 µM. In addition, compounds 4 and 5 also showed remarkable growth inhibitory activity to Artemia salina larvae.

Concave-lens-like long-period fiber grating bidirectional high-sensitivity bending sensor.

A novel bidirectional high-sensitivity fiber-optic bending sensor based on the concave-lens-like long-period fiber grating (CLL-LPFG) is designed and demonstrated. The CLL-LPFG is composed by an array of arc-shaped grating planes, and accordingly, its refractive index modulation serves as a concave lens. As a result, the eigencladding mode of the device gets closer to the device surface than the conventional counterpart. Therefore, the proposed sensor provides a more sensitive result. The experimental results show that the bending sensitivities of the CLL-LPFG reach -32.782 nm/m-1 within the bending range of 0-2.08 m-1, which is about sixfold compared to the reported arts. The sensitivity can be potentially improved by optimizing the grating parameters, and the temperature characteristics of the CLL-LPFG can be used to manipulate the grating spectrum.

Realizing torsion detection using berry phase in an angle-chirped long-period fiber grating.

We demonstrate the fabrication of an angle-chirped long-period fiber grating (ACLPFG) in a single-mode fiber via CO2 laser pulses. Because of the Berry phase introduced by the ACLPFG, the interference acquires an extra phase difference determined by the torsion of the device. By using that unique characteristic of the proposed device, a high sensitivity sine function torsion response is achieved. The torsion sensitivity is significantly improved, and the temperature crosstalk is effectively avoided by using the relative measurement technology. The torsion sensitivity is ~16 folds (~0.94 nm/ (rad/m)) higher than that of the normal long-period fiber grating (LPFG) with only ~0.006 nm/°C temperature crosstalk within the range of 25-80 °C, which is ~10 folds lower than that of the normal LPFG.

Common Carotid Artery Sonography Versus Transthoracic Echocardiography for Cardiac Output Measurements in Intensive Care Unit Patients.

OBJECTIVES: This study was designed to test the effectiveness of common carotid artery sonography in comparison with transthoracic echocardiography (TTE) for cardiac output measurements to provide an easier alternative for cardiac output monitoring in the intensive care unit. METHODS: This study included 148 patients who had common carotid artery Doppler examinations and TTE performed within 8 hours of each other, and the cardiac output measurement results were compared with each other. RESULTS: The mean age of the participants ± SD was 56.8 ± 16.2 years, with male patients composing 54.7% of the cohort. There was no significant difference in carotid and TTE cardiac output between different sexes, age groups, patients with and without mechanical ventilation, and primary indication groups. The overall intraclass correlation coefficient between the carotid and TTE cardiac output was 0.537. In patients with septic shock, multiple trauma, and respiratory failure, the intraclass correlation coefficients between TTE and carotid cardiac output were 0.241, 0.061, and 0.095, respectively. CONCLUSIONS: Carotid cardiac output shows moderate agreement with TTE cardiac output; thus, its use may be considered as an alternative for estimating cardiac output in emergencies and when TTE cardiac output is unobtainable. However, in patients with septic shock, multiple trauma, and respiratory failure, the use of carotid cardiac output is not recommended.

In vivo and in vitro induction of the apoptotic effects of oxysophoridine on colorectal cancer cells via the Bcl-2/Bax/caspase-3 signaling pathway.

Oxysophoridine (OSR) is a major active alkaloid extracted from Sophoraalopecuroides L. The aim of the present study was to investigate the induction of the apoptotic effects of OSR on colorectal cancer cells in vivo and in vitro. The results of the MTT and colony formation assays demonstrated that the proliferation of HCT116 cells was inhibited by OSR in vitro. The characteristics of cellular apoptosis in OSR-treated HCT116 cells were analyzed by Hoechst 33258 staining. It was also observed that the expression of caspase-3, B-cell lymphoma-2 (Bcl-2) associated X protein (Bax) and cytochrome c increased significantly upon OSR treatment. However, the expression of Bcl-2 and poly ADP-ribose polymerase-1 (PARP-1) was downregulated in OSR-treated cells compared with untreated cells. The in vivo experiments identified that OSR significantly inhibited the growth of the transplanted mouse CT26 tumor tissue, upregulated the expression of caspase-3, Bax and cytochrome c and downregulated the expression of Bcl-2 and PARP-1, as detected by reverse transcription-quantitative polymerase chain reaction and western blotting. It may be concluded that OSR significantly induced apoptotic effects on colorectal cancer cells in vivo and in vitro, and that its mechanism may be associated with the Bcl-2/Bax/caspase-3 signaling pathway.

Dual Inhibition of Topoisomerase II and Tyrosine Kinases by the Novel Bis-Fluoroquinolone Chalcone-Like Derivative HMNE3 in Human Pancreatic Cancer Cells.

Both tyrosine kinase and topoisomerase II (TopII) are important anticancer targets, and their respective inhibitors are widely used in cancer therapy. However, some combinations of anticancer drugs could exhibit mutually antagonistic actions and drug resistance, which further limit their therapeutic efficacy. Here, we report that HMNE3, a novel bis-fluoroquinolone chalcone-like derivative that targets both tyrosine kinase and TopII, induces tumor cell proliferation and growth inhibition. The viabilities of 6 different cancer cell lines treated with a range of HMNE3 doses were detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cellular apoptosis was determined using Hoechst 33258 fluorescence staining and the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) assay. The expression of activated Caspase-3 was examined by immunocytochemistry. The tyrosine kinase activity was measured with a human receptor tyrosine kinase (RTK) detection kit using a horseradish peroxidase (HRP)-conjugated phosphotyrosine (pY20) antibody as the substrate. The topoisomerase II activity was measured using agarose gel electrophoresis with the DNA plasmid pBR322 as the substrate. The expression levels of the P53, Bax, Bcl-2, Caspase-3, -8, -9, p-cSrc, c-Src and topoisomerase II proteins were detected by western blot analysis. The proliferation of five of the six cancer cell lines was significantly inhibited by HMNE3 at 0.312 to 10 µmol/L in a time- and dose-dependent manner. Treatment of the Capan-1 and Panc-1 cells with 1.6 to 3.2 µM HMNE3 for 48 h significantly increased the percentage of apoptotic cells (P<0.05), and this effect was accompanied by a decrease in tyrosine kinase activity. HMNE3 potentially inhibited tyrosine kinase activity in vitro with an IC50 value of 0.64±0.34 µmol/L in Capan-1 cells and 3.1±0.86 µmol/L in Panc-1 cells. The activity of c-Src was significantly inhibited by HMNE3 in a dose- and time-dependent manner in different cellular contexts. Compared with the control group, HMNE3 induced increased expression of cellular apoptosis-related proteins. Consistent with cellular apoptosis data, a significant decrease in topoisomerase IIß activity was noted following treatment with HMNE3 for 24 h. Our data suggest that HMNE3 induced apoptosis in Capan-1 and Panc-1 cells by inhibiting the activity of both tyrosine kinases and topoisomerase II.

Nonylphenol Toxicity Evaluation and Discovery of Biomarkers in Rat Urine by a Metabolomics Strategy through HPLC-QTOF-MS.

Nonylphenol (NP) was quantified using liquid chromatography tandem mass spectrometry (LC-MS/MS) in the urine and plasma of rats treated with 0, 50, and 250 mg/kg/day of NP for four consecutive days. A urinary metabolomic strategy was originally implemented by high performance liquid chromatography time of flight mass spectrometry (HPLC-QTOF-MS) to explore the toxicological effects of NP and determine the overall alterations in the metabolite profiles so as to find potential biomarkers. It is essential to point out that from the observation, the metabolic data were clearly clustered and separated for the three groups. To further identify differentiated metabolites, multivariate analysis, including principal component analysis (PCA), orthogonal partial least-squares discriminant analysis (OPLS-DA), high-resolution MS/MS analysis, as well as searches of Metlin and Massbank databases, were conducted on a series of metabolites between the control and dose groups. Finally, five metabolites, including glycine, glycerophosphocholine, 5-hydroxytryptamine, malonaldehyde (showing an upward trend), and tryptophan (showing a downward trend), were identified as the potential urinary biomarkers of NP-induced toxicity. In order to validate the reliability of these potential biomarkers, an independent validation was performed by using the multiple reaction monitoring (MRM)-based targeted approach. The oxidative stress reflected by urinary 8-oxo-deoxyguanosine (8-oxodG) levels was elevated in individuals highly exposed to NP, supporting the hypothesis that mitochondrial dysfunction was a result of xenoestrogen accumulation. This study reveals a promising approach to find biomarkers to assist researchers in monitoring NP.

[Rapid Identification of Fresh-cut and Sulphur Fumigation Processed Fritillaria thunbergii Bulb Slices Based on Near-infrared Spectroscopy].

OBJECTIVE: A rapid identification model of the fresh-cut and sulphur fumigation processed Fritillaria thunbergii bulb slices was developed by near-infrared spectroscopy (NIR) with chemometrics method. METHODS: 186 batches of Fritillaria thunbergii bulb slices were collected from the two main producing areas Ningbo and Pan'an in Zhejiang Province, and the near-infrared spectrums were gathered to establish the qualitative identification model by discriminant analysis. RESULTS: The identification model was developed by choosing the spectrum of 9,881.46-4,119.20 cm(-1) and "MSC + spectrum + Ns" to the original spectral preprocessing, and then was verified by prediction set, with 100% identify accuracy. CONCLUSION: The rapid identification model of the fresh-cut and sulphur fumigation processed Fritillaria thunbergii bulb slices by NIR is feasible and efficient.

Planifilum yunnanense sp. nov., a thermophilic thermoactinomycete isolated from a hot spring.

A thermophilic actinomycete, strain LA5(T), was isolated from a hot spring in Yunnan province, People's Republic of China. The isolate grew aerobically at temperatures of 50-75 degrees C. Aerobic mycelia were not observed. Single spores were produced along the substrate hypha. Strain LA5(T) was characterized chemotaxonomically by having MK-7 as the predominant menaquinone and iso-C(17 : 0) (27.7 %) and C(16 : 0) (22.4 %) as the major fatty acids. The cell wall contained meso-diaminopimelic acid. The DNA G+C content was 56.8 mol%. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain LA5(T) belongs to the genus Planifilum. Levels of DNA-DNA relatedness between strain LA5(T) and Planifilum fimeticola H0165(T) and Planifilum fulgidum 500275(T) were 43.6 and 52.7 %, respectively. On the basis of phenotypic properties and phylogeny, strain LA5(T) represents a novel species of the genus Planifilum, for which we propose the name Planifilum yunnanense sp. nov., with the type strain LA5(T) (=CCTCC AA206002(T)=KCTC 13052(T)).

[Determination of selenium in Chinese herbs by hydride generation atomic fluorescence spectrometry].

A method for the determination of selenium by hydride generation atomic fluorescence spectrometry (HG-AFS) was proposed in this paper. The experimental conditions including the temperature of atomizer, height of atomizer, lamp current, flow rate of carrier gas, concentration of KBH4, and acidic medium that affect the generation of hydride and the sensitivity of the method were investigated and optimized. The influence of coexisting foreign ions on the determination of selenium was also investigated. The detection limit of the proposed method was found to be 0.21 ng.mL-1. The proposed method was successfully applied to the determination of selenium in ten kinds of Chinese herbs, and the recoveries were in the range of 95%-105%.