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Magnetic anomaly detection (MAD) is a passive method used to detect the ferromagnetic objects by revealing the anomalies in the ambient Earth magnetic field. This article proposed a novel MAD algorithm based on signal modulation for magnetic sensor array. The new method transforms the original magnetic anomaly into a modulated signal and then detects the target magnetic anomaly signal by using a time–frequency analysis method. Compared with traditional algorithms, the MAD algorithm proposed in this article has three advantages: first, the influence of geomagnetic background is suppressed by calculating the magnetic field difference of the array sensor, and the trend of magnetic field difference is removed by empirical mode decomposition. Second, it properly fuses the magnetic anomaly signal of the sensor array and uses the time–frequency analysis method, which can improve the detection ability of weak magnetic anomaly signals. Third, the new method does not depend on the motion state and characteristics of the target, and it has a good adaptability to the background magnetic field. The simulation results show that this novel detection method has a good ability in the low signal-to-noise ratio (SNR) anomalies detection. For weak magnetic anomaly with an SNR of −6.9 dB, the detection probabilities and false alarm rate are about 0.9648 and 0.001, respectively. The real-world detection experiment proved that this algorithm can detect the weak magnetic anomaly in the geomagnetic background.

Metallic glasses with high magnetomechanical power efficiency are widely used in laminated magneto-electric devices, from passive magnetometers and solid-state converters to very-low-frequency emitters. The remaining challenge is to simultaneously enhance the magnetomechanical power coupling and quality factors that are usually counterbalanced in metallic glasses. Here, we investigate the relaxations and surface configurations in annealed metallic glasses and their impacts on the magnetomechanical properties. We found an opportune annealing condition that maximizes the power efficiency when a surface-oxidation film of boron oxide is formed with excessive boron atoms that are separated from a surface-crystalline film. We confirm the findings by demonstrating a magneto-electric gyrator that has a power efficiency of 96% and magneto-electric antennas that have an increased emission intensity by 20% than that with traditionally annealed metallic glasses.

A miniature three-axis induction magnetometer (IM) for borehole logging was designed, manufactured, and tested. The form of the IM is a cube with 12 coils at edges, which are embedded in a ring cylinder. Thus, the 12 coils are placed along the x , y , and z axes. Each axis consists of four coils that are connected in series. The length, inner diameter, and outer diameter of the ring cylinder are 40, 43, and 64 mm, respectively. The mass of the IM is 450 g. The working frequency bandwidth is set within 1 Hz–10 kHz. The equivalent induction magnetic noise level of the IM is less than 10 pT/√Hz at 100 Hz for three axes. The features and the noise performances of the IM show the potential for its use in borehole logging.

Quantitative modeling of the transient electromagnetic (TEM) response requires consideration of the full transmitter waveform, i.e., not only the specific current waveform in a half cycle but also the bipolar repetition. In this paper, we present a novel temporal interpolation and convolution (TIC) method to facilitate the accurate TEM modeling. We first calculate the temporal basis response on a logarithmic scale using the fast digital-filter-based methods. Then, we introduce a function named hamlogsinc in the framework of discrete signal processing theory to reconstruct the basis function and to make the convolution with the positive half of the waveform. Finally, a superposition procedure is used to take account of the effect of previous bipolar waveforms. Comparisons with the established fast Fourier transform method demonstrate that our TIC method can get the same accuracy with a shorter computing time.

In this paper, a quantitative model for describing the sensitivity of fluxgate sensors is presented. The model, which is illustrated by introducing the periodically changed apparent permeability as a periodic function, can accurately predict the sensitivity of fluxgate sensors. Compared with the previous works, the sensitivity of fluxgate can be predicted more simply and accurately. The model is verified by measuring the time-varying apparent permeability of a permalloy ring core. Sensitivity of a ring-core configuration fluxgate and a Foster configuration fluxgate is measured. The experiments results validate the model furthermore. The model can be applied to describe the sensitivity of other configurations by modifying the apparent permeability formula in the model. This method provides a new avenue to study the sensitivity of the fluxgate sensors.

A 2 nV/ $\surd $ Hz and 10 fA/ $\surd $ Hz at 1-Hz ultralow noise preamplifier is designed to improve the sensitivity of the induction magnetometer (IM) from 0.1 Hz to 10 kHz. Meanwhile, the noise characteristics of IM are analyzed and distinguished. A novel optimization method to find the minimum length of the core under the required noise level and the limited IM weight is proposed. Furthermore, an optimal IM prototype from 0.1 Hz to 10 kHz is developed with the noise level of 1 pT/ $\surd $ Hz at 1 Hz and 1.5 fT/ $\surd $ Hz at 2 kHz. The length is only 360 mm and the weight is 1.5 kg. The measurement results of the IM also confirm the theoretical noise model and the optimization method.

A narrowband, high sensitivity, and low-power consumption induction magnetometer (IM) receiving sensor is designed, built, and tested for through-the-Earth (TTE) communications in this paper. The optimization method is described mathematically and applied for building an IM (central frequency 3180 Hz and 3-dB bandwidth 200 Hz). In this paper, we move the resonant frequency of the coils to the central frequency and optimize the parameters of the IM to minimize the equivalent input magnetic noise level to 7 fT/√Hz within 3-dB bandwidth. The IM dimensions are Φ 40 mm × 350 mm and the power consumption is

Induction magnetometer (IM) is the transducer for measuring the magnetic field's variations, which is widely used in space research, geophysical exploration, and so on. Among all kinds of IMs, IMs of 0.1 mHz to 1 Hz with negative feedback flux and chopper stabilized amplifiers are especially popular used for the magnetotelluric method in geophysical explorations. In this paper, the equivalent input magnetic noise (EIMN) of IMs of 0.1 mHz to 1 Hz is discussed and modeled. Seven main noise sources are described, numerical evaluated, and experimental modeled separately. At last, an experimental IM is built and its EIMN is measured low to 0.1 mHz to confirm the theoretical model.

Objective In order to develop and compare mPEG-PLA micelles and mPEG-PLA/TPGS mixed micelles, with the intention to develop a highly efficient formulation for nimodipine (NIM), NIM-loaded micelles and mixed micelles were made and their pharmacokinetics were studied. Methods Single factor experiments and orthogonal experiments were designed to optimize the final preparation process, characterizations and drug release behaviors were studied. Pharmacokinetics of NIM micelles, NIM mixed micelles were researched and were compared to NIM solution. Results Micelles and mixed micelles were prepared by solvent evaporation method, with relatively high drug loading efficiency and within nano-particle size range. The CMC value of mPEG-PLA was lower than that of mPEG-PLA/TPGS. The results of FTIR and TEM confirmed the spherical core–shell structure of micelles as well as mixed micelles, and the encapsulation of NIM inside the cores. In vitro release showed that micelles and mixed micelles had sustained release effect in the forms of passive diffusion and dissolution process, respectively. Following intraperitoneal administration (5 mg/kg), micelles and mixed micelles were absorbed faster than solution, and with larger MRT (0 – t ) , smaller CL z and larger AUC (0 – t ) as compared to that of solution, which showed micelles and mixed micelles had higher retention, slower elimination and higher bioavailability. This experiment also showed that mixed micelles released NIM more stably than micelles. By evaluate the bioequivalence, NIM micelles and NIM mixed micelles were testified non-bioequivalent to NIM solution. Conclusion Micelles and mixed micelles could sustain the NIM concentrations more efficiently in plasma as compared to solution. Mixed micelles were the best ones since they had high loading content and released more stably. Thus, apprehending micelles and mixed micelles were suited as poor aqueous solubility drug carriers, and mixed micelles were better due to their high loading content and more stable release.

The induction magnetometer (IM) is one of the most widely used tools to measure the variation of magnetic field in space research, geophysical exploration, environment monitoring, and so on. In this work, we proposed two different kinds of optimization methods for an IM in the frequency range of 0.1 mHz to 1 kHz; the first is for a known core and the other is for a limited IM's volume. The optimum IM we designed, with weight less than 3 kg, diameter 45 mm, length 850 mm, and 1Hz noise level 0.2 pT/√Hz, made a new record of IM for the Magnetotelluric (MT) method and was beneficial to those in the MT field working in oil and mineral explorations. The experimental results of the optimum IM fully confirm the theoretical optimization.

This research was designed to explore the role of joint and nonarticular clinical manifestations traditionally evaluated in Chinese herbal medicine in predicting efficacy of treatment for rheumatoid arthritis.Three hundred ninety-six patients were randomly divided to receive Western medicine (WM) therapy, 197 cases; and traditional Chinese herbal medicine (TCM), 199 cases. A complete physical examination and 18 clinical manifestations typically assessed in TCM were recorded before the randomization. The WM therapy included diclofenac extended action tablets, methotrexate, and sulfasalazine. The TCM therapy included Glucosidorum Tripterygll Totorum tablets and Yishen Juanbi tablets. The American College of Rheumatology (ACR) response criteria were used for efficacy evaluation. All data were analyzed using the SPSS11.5 statistical package.ACR20 and 50 responses with WM treatment were higher at 24 weeks than in the TCM group. In the WM group, 89% achieved ACR20 whereas 65.8% on TCM reached this response In the WM group, efficacy was negatively related to subjective symptoms of dizziness, and positively related to joint tenderness and thirst as recorded at entry. In contrast, in the TCM group the efficacy was positively related to joint tenderness and joint pain, and negatively related to the joint stiffness and more nocturia.Symptoms including those not directly related to joints and those inquired about in TCM may have influence on the efficacy of therapy, and might merit further study to ascertain if they can be helpful to guide specific therapy.

In this article, the dielectric dispersive models in Terahertz range are determined with the classical dielectric theory and genetic algorithm (GA). Four samples' models, glass, plywood, spruce-pine-fir (SPE) wood and drywall, are established. And the models have been proved to have a good agreement with the experimental results measured by terahertz technology and terahertz time domain spectroscopy and other equipments. It is concluded that the determined models are effective in this frequency range, and GA is an effective tool for calculating the models' parameters. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2540–2545, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22776

Tripterygium wilfordii Hook F. (TwHF) based therapy has been proved as effective in treating rheumatoid arthritis (RA), yet the predictors to its response remains unclear. A two-stage trial was designed to identify and verify the baseline symptomatic predictors of this therapy. 167 patients with active RA were enrolled with a 24-week TwHF based therapy treatment and the symptomatic predictors were identified in an open trial; then in a randomized clinical trial (RCT) for verification, 218 RA patients were enrolled and classified into predictor positive (P+) and predictor negative (P−) group and were randomly assigned to accept the TwHF based therapy and Methotrexate and Sulfasalazine combination therapy (M&S) for 24 weeks, respectively. Five predictors were identified (diuresis, excessive sweating, night sweats for positive; and yellow tongue-coating, thermalgia in the joints for negative). In the RCT, The ACR 20 responses were 82.61% in TwHF/P+ group, significantly higher than that in TwHF/P− group (P = 0.0001) and in M&S/P+ group (P < 0.05), but not higher than in M&S/P− group. Similar results were yielded in ACR 50 yet not in ACR 70 response. No significant differences were detected in safety profiles among groups. The identified predictors enable the TwHF based therapy more efficiently in treating RA subpopulations.

This study is designed to compare the efficacy and safety of traditional Chinese medicine (TCM) with western medicine (WM) in the management of rheumatoid arthritis (RA). This is a 24-week, randomized, multicenter, single-blind study comparing TCM with WM (as used in China) carried out between June 2002 and December 2004 in nine research centers in China, involving 489 patients. Patients were randomized to receive TCM (n = 247), MTX and SSZ (n = 242). MTX was started at a dose of 5 mg to a final dose of 7.5–15 mg weekly. The maintenance dose was 2.5–7.5 mg weekly. The starting dose of SSZ was 0.25 g bid, increasing by 0.25 g a day once a week to a final dose of 0.5–1 g qid. The maintenance dose was 0.5 g tid to qid. Primary end point was the proportion of patients with response according to the American College of Rheumatology 20 % improvement criteria (ACR20) at weeks 24. At 24 weeks, ACR20 responses were 53.0 % in TCM group and 66.5 % in WM group, (P < 0.001) at 24 weeks. ACR 50 responses were 31.6 % of TCM group and 42.6 % in WM group, (P = 0.01). ACR70 responses were 12.6 % in TCM group and 17.4 % in WM group, (P = 0.14). Side effects were observed more frequently in WM group. In this study, ACR20, ACR50 responses at 24 weeks were significantly better in the WM treated group, by intention to treat (ITT) and per protocol analysis. The ACR 70 response showed no significant difference between the two groups. TCM, while effective in treating RA, appears to be less effective than WM in controlling symptoms, but TCM is associated with fewer side effects.

When the transient electromagnetic (TEM) method is used in prospecting, primary excitation in a transient system can have any shape. This paper obtains the response of these waveforms by the time-domain approach, which approximates the energizing pulse as a superposition of step functions. We also used a new hankel transform filters made by F.N Kong to calculate the response of step waveform for in-loop configuration. As the step response is logarithmic sampling, cubic spline interpolation is used for the accurate convolution. By the analysis of some normal waveforms, we find that our method is effective in calculating the response of any arbitrary pulse in TEM method.

In this article, a novel 0.2 THz imaging system is presented. It is made up of Gunn oscillator, dual mode antenna, off-axis reflector antenna and Schottky diode detector. It has many merits such as: small-size, low-cost, low-power-supply, and room-temperature-operational compared to the THz-time domain spectrometer (THz-TDS) which has a large-size, is expensive, and has strict requirements to working conditions.

The predictive roles of symptom combination traditionally evaluated in traditional Chinese medicine (TCM) in the treatment of rheumatoid arthritis (RA) were explored. Three hundred and ninety six patients were randomly divided into 197 subjects receiving Western medicine therapy (WM) and 199 subjects receiving TCM therapy (TCM). A complete physical examination and 18 clinical manifestations typically assessed in TCM were recorded before the randomization. The ACR responses were used for efficacy evaluation. ACR20 and 50 responses with WM treatment were higher than in the TCM group. The 18 symptoms in RA could be clustered into 4 symptom combinations with factor analysis, which represent joint symptoms, cold pattern, deficiency pattern and hot pattern in TCM respectively. TCM would be more effective in patients with weak-symptom combination 3 (deficiency pattern in TCM), and WM would be more effective in patients with symptom combination 2 (cold pattern in TCM). Symptom combinations judged with TCM may have influence on the efficacy of therapy in the treatment of RA.

OBJECTIVE To analyze the indications of the therapies for rheumatoid arthritis (RA) with neural network model analysis. METHODS Three hundred and ninety-seven patients were included in the clinical trial from 9 clinical centers. They were randomly divided into Western medicine (WM) treated group, 194 cases; and traditional Chinese herbal medicine (CM) treated group, 203 cases. A complete physical examination and 18 common clinical manifestations were prepared before the randomization and after the treatment. The WM therapy included voltaren extended action tablet, methotrexate and sulfasalazine. The CM therapy included Glucosidorum Tripterygii Totorum Tablet and syndrome differentiation treatment. The American College of Rheumatology 20 (ACR20) was taken as efficacy evaluation. All data were analyzed on SAS 8.2 statistical package. The relationships between each variable and efficacy were analyzed, and the variables with P

Objective To evaluate the correlations between clinical symptoms and treatment efficacy in patients with rheumatoid arthritis (RA). Methods Four hundred and thirteen patients were included in the clinical trial from 9 clinical centers. They were randomly divided into Western medicine-treated group with 204 cases and Chinese herbal drug-treated group with 209 cases. Eighteen clinical symptoms were evaluated before and after treatment. The Western medicine therapy included voltaren extended release tablets, methotrexate and sulfasalazine. The Chinese herbal drug therapy included glucosidorum Tripterygii totorum tablets and Yishen Juanbi Tablets combined with treatment based on syndrome differentiation. The American College of Rheumatology 20 (ACR20) was used as efficacy evaluation criteria. Results In the Chinese herbal drug-treated group, clinical symptoms such as arthralgia and tenderness of joints were positively correlated with the efficacy after 12-week treatment, while frequent urination at night was negatively correlated. In the same group, tenderness of joints and fever were positively correlated with the efficacy after 24-week treatment, while deep-colored and turbid urine was negatively correlated. In the Western medicine-treated group, tenderness of joints and thirst were positively correlated with the efficacy after 12-week treatment, while vertigo was negatively correlated. And in the same group, tenderness of joints was positively correlated with the efficacy after 24-week treatment, while heaviness of limbs was negatively correlated to the efficacy. The statistical results showed that the treatment efficacy was improved when the correlated symptoms were included in the indications. Conclusion The treatment efficacy of RA is correlated with some symptoms, so further studies should proceed on these correlations in order to achieve better treatment outcome.

Magnetic anomaly detection (MAD) is an effective method for the detection of ferromagnetic targets against background magnetic fields. Currently, the performance of MAD systems is mainly limited by the background geomagnetic noise. Several techniques have been developed to detect target signatures, such as the synchronous reference subtraction (SRS) method. In this paper, we propose an adaptive coherent noise suppression (ACNS) method. The proposed method is capable of evaluating and detecting weak anomaly signals buried in background geomagnetic noise. Tests with real-world recorded magnetic signals show that the ACNS method can excellently remove the background geomagnetic noise by about 21 dB or more in high background geomagnetic field environments. Additionally, as a general form of the SRS method, the ACNS method offers appreciable advantages over the existing algorithms. Compared to the SRS method, the ACNS algorithm can eliminate the false target signals and represents a noise suppressing capability improvement of 6.4 dB. The positive outcomes in terms of intelligibility make this method a potential candidate for application in MAD systems.