Suppression of frequency-mixing effect for pm-level heterodyne interferometers based on "zero coupling" optical path length control.

Optical path length (OPL) noise resulting from stray light significantly constrains interferometry displacement measurements in the low-frequency band. This paper presents an analytical model considering the presence of stray light in heterodyne laser interferometers. Due to the cyclic nonlinear coupling effect, there will be some special OPLs of stray light, minimizing the frequency-mixing impact to zero. Consequently, we propose a noise suppression scheme that locks the OPL of stray light at the zero coupling point. Therefore, we significantly enhanced the interference displacement measurement noise within the low-frequency band. Experimental results show that the interferometer achieves a displacement noise level lower than 6 pm/Hz1/2 covering 1 mHz.

Evaluation of the efficacy of wrist arthroscopic surgery for aseptic necrosis of lunate bone.

OBJECTIVE: To explore the use of wrist arthroscopy for treatment of aseptic necrosis of lunate bone and its curative effect. METHODS: From March 2012 to January 2016, 12 patients with aseptic necrosis of lunate bone underwent necrotic lunate bone extirpation assisted by wrist arthroscopy, and the scaphocapitate joint treated with fusion-stabilization were selected. Among these patients, 10 patients were male and two patients were female. The age of these patients ranged from 25 to 42 years old, with an average age of 32 years old. These lesions were located in the right hand in eight patients, and in the left hand in four patients. Lichtman stage: stage IIIA in two patients, and stage IIIB in 10 patients. All patients were diagnosed by anterior lateral radiographs and magnetic resonance imaging (MRI). From the second day after the surgery, patients underwent active motion for the metacarpophalangeal joint and interphalangeal joints. When the X-ray film indicated that the fracture had healed, patients began to resume their daily activities and work. After surgery, the plain films of all planes, including the axial plane of the scaphoid, were taken every month, until fracture healing. All patients were followed up for a mean duration of 8 months, and the Mayo wrist score was used to assess the range of motion of the wrist joint and grip force during the follow-ups for objective function evaluation. RESULTS: Fracture healing was obtained in all patients within 9-12 weeks after the operation, and average healing time was 10 weeks. The duration of follow-up ranged between 6-14 months, and the mean duration was 8 months. According to the modified Mayo wrist score, the objective function of the wrist joint was evaluated as follows: flexion and extension range of the wrist joint was 40°-110°, with an average of 105°, which was 80% of that of the unaffected side. Radioulnar deviation was 45°-80°, with an average of 55°, which was 82% of that of the unaffected side. Grip force was 25-48 kg, with an average of 40 kg, which was 84% of that of the unaffected side. The modified Mayo wrist score was good in eight patients, acceptable in three patients, and poor in one patient. CONCLUSIONS: Wrist arthroscopy is an effective and feasible tool for the treatment of aseptic necrosis of the lunate bone, and the right kind of surgical procedure should be selected for different stages of the disease, and wrist arthroscopy is applied timely, in order to achieve the desired therapeutic effect.

Artificial intelligence based Chinese clinical trials eligibility criteria classification / 生物医学工程学杂志

Subject recruitment is a key component that affects the progress and results of clinical trials, and generally conducted with eligibility criteria (includes inclusion criteria and exclusion criteria). The semantic category analysis of eligibility criteria can help optimizing clinical trials design and building automated patient recruitment system. This study explored the automatic semantic categories classification of Chinese eligibility criteria based on artificial intelligence by academic shared task. We totally collected 38 341 annotated eligibility criteria sentences and predefined 44 semantic categories. A total of 75 teams participated in competition, with 27 teams having submitted system outputs. Based on the results, we found out that most teams adopted mixed models. The mainstream resolution was applying pre-trained language models capable of providing rich semantic representation, which were combined with neural network models and used to fine-tune the models with reference to classifier tasks, and finally improved classification performance could be obtained by ensemble modeling. The best-performing system achieved a macro

External right-angle measurement using a two-autocollimator system.

We report on a non-contact method for external right-angle measurement using two autocollimators. A precise mathematical model is deduced to evaluate and deduct the measuring error. The values measured with our method are very coincident compared with the results measured by a ZYGO interferometer. The measuring accuracy is superior to 0.1 arcsec for the right-angle errors within 3.0 arcsec and becomes 0.4 arcsec for the extended right-angle errors within 8.0 arcsec. This method can be widely used in situations for external right-angle measurement, such as angle measurement for the body of torsion balance and test mass in spaceborne laser interferometry.

Inter-satellite laser link acquisition with dual-way scanning for Space Advanced Gravity Measurements mission.

Laser link acquisition is a key technology for inter-satellite laser ranging and laser communication. In this paper, we present an acquisition scheme based on the differential power sensing method with dual-way scanning, which will be used in the next-generation gravity measurement mission proposed in China, called Space Advanced Gravity Measurements (SAGM). In this scheme, the laser beams emitted from two satellites are power-modulated at different frequencies to enable the signals of the two beams to be measured distinguishably, and their corresponding pointing angles are determined by using the differential power sensing method. As the master laser beam and the slave laser beam are decoupled, the dual-way scanning method, in which the laser beams of both the master and the slave satellites scan uncertainty cones simultaneously and independently, can be used, instead of the commonly used single-way scanning method, in which the laser beam of one satellite scans and that of the other one stares. Therefore, the acquisition time is reduced significantly. Numerical simulation and experiments of the acquisition process are performed using the design parameters of the SAGM mission. The results show that the average acquisition time is less than 10 s for a scanning range of 1-mrad radius with a success rate of more than 99%.

Charactering the metabolism of cryptotanshinone by human P450 enzymes and uridine diphosphate glucuronosyltransferases in vitro.

Cryptotanshinone (CT) is the main active component in the root of Salvia miltiorrhiza Bunge (SMB) that displays antibacterial, anti-inflammatory and anticancer activities. In this study, we characterized phase I and phase II metabolism of CT in human liver microsomes in vitro and identified the metabolic enzymes (CYPs and UGTs) involved. The metabolites of CT generated by CYPs were detected using LC-MS/MS and the CYP subtypes involved in the metabolic reactions were identified using chemical inhibitors of CYP enzymes and recombinant human CYP enzymes (CYP1A2, CYP2A6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4). Glucuronidation of CT was also examined, and the UGT subtypes involved in the metabolic reactions were identified using recombinant human UGT enzymes (1A1, 1A3, 1A4, 1A5, 1A6, 1A7, 1A8, 1A9, 1A10, 2B4, 2B7, 2B15 and 2B17). After adding NADPH to the human liver microsomes incubation system, CT was transformed into 6 main dehydrogenation and hydroxylation metabolites. CYP2A6, CYP3A4 and CYP2C19 were the major contributors to the transformation of its hydroxylation metabolites. CYP2C19, CYP1A2 and CYP3A4 were the major contributors to the transformation of its hydrogenation metabolites in human liver microsomes. This study showed that the metabolites at m/z of 473 were mediated by UGT1A9 and that the metabolites at m/z of 489 were mediated by UGT2B7 and UGT2B4. CT was extensively metabolized by UGTs following metabolism by CYPs in the liver.

Molecular mechanism of polygonatum sibiricum polysaccharide in the prevention and treatment of postmenopausal osteoporosis / 中国组织工程研究

BACKGROUND: Previous studies have found that polygonatum sibiricum polysaccharide (PSP) exhibits anti-osteoporosis effect, but its therapeutic effect in ovariectomized osteoporotic rats and the molecular mechanisms are poorly understood. OBJECTIVE: To investigate the effect of administration of PSP on the bone microstructure, bone mineral density as well as osteoblast- and osteoclast-related gene expression in rats. METHODS: Twenty-five infertile female Sprague-Dawley rats aged 3 months were randomly allotted into five groups (n=5 per group): sham operation (same volume normal saline), model, zoledronate (0.2 mg/kg?d), high-dose PSP (800 mg/kg?d) and medium-dose PSP (400 mg/kg?d) groups. All rats were subjected to ovariectomy except sham operation group. The administration was intragastrically given every 2 days beginning at 7 days after modeling and lasted 12 weeks. Then, the rats were sacrificed, and the uterus was weighed. The bilateral tibias were removed, one side for histomorphometric analysis by micro-CT, and the other one for RNA detection by qualified PCR. RESULTS AND CONCLUSION: Compared with the sham operation group, the rat body mass in the model group was significantly increased and the weight of uterus was significantly decreased (P < 0.05). Compared with the model group, zoledronate and high-dose PSP could significantly alleviate the excessive increase in body mass (P < 0.05). The bone mineral density in the model group was decreased by 63% compared with the sham operation group (P < 0.01), Compared with the model group, after 12-week high-dose PSP and zoledronate administration, the bone mineral density was increased by 44% and 38%, respectively (P < 0.01); the trabecular bone volume fraction and trabecular number rose significantly(P<0.05),while the trabecular separation decreased significantly(P<0.05).In vivo,PSP could significantly promote the expression levels of osteoblast-related genes (alkaline phosphatase, RUNX2, Col1a1 and osteocalcin), and significantly inhibit the expression levels of osteoblast-related genes (ACP5 and CTSK) (P < 0.05). These results imply that high-dose PSP can reduce bone loss and decrease of bone mineral density, improve the destruction of bone microstructure, as well as promote osteoblast-related genes but inhibit osteoclast-related gene mRNA expression in the ovariectomized rats.

Analysis of non-linearity in differential wavefront sensing technique.

An analytical model of a differential wavefront sensing (DWS) technique based on Gaussian Beam propagation has been derived. Compared with the result of the interference signals detected by quadrant photodiode, which is calculated by using the numerical method, the analytical model has been verified. Both the analytical model and numerical simulation show milli-radians level non-linearity effect of DWS detection. In addition, the beam clipping has strong influence on the non-linearity of DWS. The larger the beam clipping is, the smaller the non-linearity is. However, the beam walking effect hardly has influence on DWS. Thus, it can be ignored in laser interferometer.

Analysis of the Treatment of the Syndrome Differentiation and Treatment of Dysmenorrhea of

Objective]The article summarizes in diagnosis and treatment of dysmenorrhea academic thoughts and characteristics of drug use. [Methods] Summary by readingtext and access to a large number of relevant literature,the history of famous experts,combined with the actual clinical, summarized his main syndrome differentiation and treatment of dysmenorrhea thought and medication. [Results] Fu Qingzhu according to the onset of time divided into 5 types of dysmenorrhea, menstruation comes or breaks suddenly when pain exists or disappears, the menstruation upcoming accompanies abdomen ache, abdominal pain after menstruation,the menstruation upcoming lower abdominal pain and hematemesis and the umbilicus pain when the menstruation upcoming.Fu Qingzhu thought according to the pathogenesis of dysmenorrhea mainly with the liver, spleen and kidney three organs close relationship, the syndrome is stagnation of the liver qi and blood deficiency, liver depression of the fire, kidney deficiency and liver qi stagnation and reversal of liver qi, deficiency of spleen Yang, treatment with soothing liver and reinforcing kidney mainly.[Conclusion] Fu Qingzhu ’s idea in the dysmenorrhea was analyzed in detail, and pointed out the mistakes in the syndrome differentiation and put forward the original opinion and treatment of medicine, in order to inherit traditional Chinese medicine academic, improve the curative effect of dysmenorrhea.

Note: Inter-satellite laser range-rate measurement by using digital phase locked loop.

This note presents an improved high-resolution frequency measurement system dedicated for the inter-satellite range-rate monitoring that could be used in the future's gravity recovery mission. We set up a simplified common signal test instead of the three frequencies test. The experimental results show that the dominant noises are the sampling time jitter and the thermal drift of electronic components, which can be reduced by using the pilot-tone correction and passive thermal control. The improved noise level is about 10(-8) Hz/Hz(1/2)@0.01Hz, limited by the signal-to-noise ratio of the sampling circuit.

A dual-heterodyne laser interferometer for simultaneous measurement of linear and angular displacements.

Picometer laser interferometry is an essential tool for ultra-precision measurements in frontier scientific research and advanced manufacturing. In this paper, we present a dual-heterodyne laser interferometer for simultaneously measuring linear and angular displacements with resolutions of picometer and nanoradian, respectively. The phase measurement method is based on cross-correlation analysis and realized by a PXI-bus data acquisition system. By implementing a dual-heterodyne interferometer with a highly symmetric optical configuration, low frequency noises caused by the environmental fluctuations can be suppressed to very low levels via common-mode noise rejection. Experimental results for the dual-heterodyne interferometer configuration presented demonstrate that the noise levels of the linear and angular displacement measurements are approximately 1 pm/Hz(1/2) and 0.5 nrad/Hz(1/2) at 1 Hz.

Protective effect of ginsenoside Rg1 again PC-12 cells in OGD injury through mTOR/Akt/FoxO3 signaling pathway / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the protective effect of ginsenoside Rg1 on oxygen-glucose deprivation (OGD) in PC-12 cells, and preliminarily discuss the potential molecular mechanism of mTOR/Akt/FoxO3 signaling pathway.</p><p><b>METHOD</b>The OGD PC-12 cell model was established. The cell viability was measured by MTT assay. After the pretreatment with Rg1 with the concentration of 10, 20, 40 micromol x L(-1) for 24 h, the cell viability was observed. Lactate dehydrogenase (LDH) release, superoxide dismutase (SOD) ac- tivity and malondialdehyde (MDA) level were detected by colorimetry assay. mTOR, p-Akt(ser473), p-Akt(tjr308), Akt, p-FoxO3, FoxO3 in cytoplasm and nucleus, and total FoxO3 protein expression were detected by Western blot assay.</p><p><b>RESULT</b>OGD could significantly in- hibit cell proliferation in 4-24 h in a time-dependent manner. After pretreatment for 24 h, Rg1 (20, 40 micromol x L(-1)) could notably elevate the cell viability and SOD viability and reduce the LDH release and MDA content. Besides, Rg1 also inhibited OGD-induced mTOR and p-Akt(ser473) decreases. After treatment for 6 h, OGD could reduce FoxO3 phosphorylation and promote FoxO3 in cytoplasm. This data suggested that Rg1 could protect PC-12 cell injury through mTOR/p-Akt/FoxO3 signaling pathway.</p><p><b>CONCLUSION</b>Ginsenoside Rg1 could attenuate OGD-induced PC-12 cell injury. Its action mechanism may be closely related to activation of mTOR/p-Akt/FoxO3 signaling pathway.</p>

Fundamental limits on the digital phase measurement method based on cross-correlation analysis.

Ultra-precision phase measurement is a key technology for state-of-the-art laser interferometry. In this paper we present a fully digital phase measurement method based on cross-correlation analysis, and analyze the measurement errors caused by sampling quantization, intrinsic white noise and non-integral-cycle sampling. The last error source results in a cyclic error that has not been reported ever. We used a high-performance data acquisition system to carry out the cross-correlation-based phase measurement, and obtained a noise level of 1.2 × 10(-6) rad/Hz(1/2)[commercial at]1 Hz. Moreover, the cyclic phase error of about 10(-2) rad/Hz(1/2), caused by non-integral-cycle sampling, had been observed. In order to demonstrate the application of this precision phase measurement method, an ultra-precision heterodyne laser interferometer, consisting of digital phase measurement system and ultra-stable optical bench, was constructed for displacement measurement. The experimental results showed that a measurement resolution of 63 pm had been achieved.

[DFT and surface-enhanced Raman scattering studies of BPA].

On the base of the vibration theory, the spectrum of bisphenol A(BPA) molecule was calculated by the density functional theory(DFT) using B3LYP/6-311G(d), and the normal Raman spectrum (NRS) of BPA was assigned in detail. The surface enhanced Raman scattering (SERS) of the BPA molecule was obtained by gold sol enhancement. The adsorption of BPA to gold surface was analyzed: in acidic pH, the molecule was adsorbed on the gold surface by =CO-, the vibration of the band O-H disappeared, and the benzene ring was perpendicular on the surface of gold sol.

Detection of bovine, goat, pig and chicken derived ingredients in animal products with universal PCR-microarray method / 生物工程学报

We analyzed the sequence of vertebrate molecular marker genes, then we selected the mitochondrial DNA (mtDNA) 16S rRNA gene as marker gene. In order to detect four kinds of animal-derived ingredients, which including bovine, goat, pig and chicken. We utilized a pair of universal primers, designed four sets of species-specific microarray probes and two pairs of quality control probes. We optimized the PCR amplifications and hybridization conditions, therefore these four kinds of animal-derived ingredients could be rapid and accurate detected by this approach. The detection limits were all reaches 1 pg. We established the detection platform of these four kinds of animal-derived ingredients. This universal PCR-microarray assay provides a new method for the identification of animal-derived ingredients in the import-export field.

PCR-mtDNA for detecting components of duck origin in foodstuff and feedstuff / 生物工程学报

Mitochondrial cytochrome oxidase III (COIII) of duck was successfully amplified by PCR-mtDNA with duck muscle DNA as the template (GenBank Accession No. DQ655706). Cloning sequence analysis shows that the 784 bp nucleotides of COIII gene were contained. Through homology analysis, we confirmed that the cytochrome oxidase III (COIII) was relatively conservative. The method of PCR-mtDNA can be designed to detect the components of duck origin. And then, the method of PCR can be applied to amplify with the muscle DNA of various animal and feedstuff as the template, repeated verification, the primer (P3, P4) with strong specificity and good stability is screened, which can only amplify the sequence of duck. The special sequence contains 226 bp, the amplified product of 226 bp was sequenced and analyzed, it showed 100% homology with duck mtDNA COIII gene, which proved the accuracy of the special primer. The test that used different concentration of DNA with P3 and P4 is the sensitive experiment by PCR. The result showed that the primer has much specialty and rather sensitivity. So it is a way to detect the duck origin in the muscle of various animal and feedstuff.