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In most coastal alluvial plains, the groundwater area of the aquifer is a rich environment that has experienced an extended period of marine deposition and is highly vulnerable to increasing urbanization. Excessive exploitation of groundwater has resulted in recent seawater intrusion and connate water leakage, leading to freshwater salinization. In this study, a novel workflow is designed for groundwater appraisal. First, revised one-dimensional direct transformation schemes were developed and applied to extensive vertical electrical sounding (VES) points sampled by a Schlumberger array to obtain the VES-based calibrated transformed resistivity (V-CTR), as calibrated by the modified reflection coefficient and novel depth correction factor. Next, the interfaces of all leaky confined aquifers (LCAs) and the saline water zone were quantitatively determined via hybrid interpretation methods. Finally, to better understand the salt level (i.e., fresh, brackish, or saline) and perform assessments of the groundwater quality, total dissolved solids (TDS) planar distributions were interpolated using two different power functions linking the V-CTR and measured TDS from the sampled boreholes for the corresponding aquifer unit. The workflow was examined based on hydrological and geophysical data acquired at the Yangtze River Delta (Nantong Region, Jiangsu Province, China). The interpreted results are of great significance for understanding the groundwater distribution associated with the Quaternary geology and hydrogeology and can be potentially used to analyze and guide the development and utilization of water resources in the study area.

Field trials were conducted to study the responses of grain yield and nitrogen (N) use efficiency at five input rates (N0, N82.5, N165, N247.5, and N330 kg ha−1) in a set of nine of the most representative rice cultivars. Grain yields of rice across the nine cultivars were increased significantly by N level. All the cultivars contained a significant linear plus plateau or quadratic relationship between N levels and grain yields.The minimum yields (means of 2 years) at N0, N82.5, N165, N247.5, and N330 level all occurred in No. 2 cultivar. Compared with the grain yield of No. 2 at different N levels, those of the maximum cultivars increased by 37.1 (No. 8), 39.1 (No. 7), 48.4 (No.3), 43.3 (No. 4), and 43.9% (No. 3), respectively. In 2011, the highest average apparent nitrogen recovery efficiency (ANRE) in grain of the 4 N levels occurred in No. 3 cultivar (45.9%), followed by No. 4, No. 6, and No. 1, and the highest average agronomic efficiency (AE) in grain of the 4 N levels occurred in No. 9 cult...

MicroRNAs (miRNAs) have emerged as important regulators in multiple myeloma (MM). miR-1271 is a tumor suppressor in many cancer types. However, the biological role of miR-1271 in MM remains unclear. In the present study, we elucidated the biological role of miR-1271 in MM. Results showed that miR-1271 was significantly decreased in primary MM cells from MM patients and MM cell lines. Overexpression of miR-1271 inhibited proliferation and promoted apoptosis of MM cells. Conversely, suppression of miR-1271 showed the opposite effect. Bioinformatics algorithm analysis predicted that smoothened (SMO), the activator of Hedgehog (HH) signaling pathway, was a direct target of miR-1271 that was experimentally verified by a dual-luciferase reporter assay. Furthermore, overexpression of miR-1271 inhibited SMO expression and HH signaling pathway. Conversely, the restoration of SMO expression markedly abolished the effect of miR-1271 overexpression on cell proliferation, apoptosis and HH signaling pathway in MM cells. Taken together, the present study suggests that miR-1271 functions as a tumor suppressor that inhibits proliferation and promotes apoptosis of MM cells through inhibiting SMO-mediated HH signaling pathway. This finding implies that miR-1271 is a potential therapeutic target for the treatment of MM.

BACKGROUND The aim of this study was to analyze reasons why open surgery was done after percutaneous vertebroplasty and kyphoplasty. MATERIAL AND METHODS Patients (587 vertebral bodies) treated with percutaneous vertebroplasty or kyphoplasty in the Xi'an Honghui Hospital of Shanxi Province from January 2008 to January 2012 were retrospectively analyzed and 13 patients were enrolled in the study. These 13 patients had serious adverse events after percutaneous vertebroplasty or kyphoplasty. Their average age was 64.5 years old. Nine patients had spinal cord injury and 4 had nerve root injury. All the patients underwent open surgery within 4-12 h after definitive diagnosis. RESULTS All 13 cases were followed up (average time 14.1 months, range 3-47 months). Reasons for open surgery included cement extravasation (6 cases, 46.2%), puncture mistake (3 cases, 23.1%), and false selection of indications (4 cases, 30.8%). At last follow-up, skin feeling was better than that before open surgery in 4 cases with nerve root injury, and muscle strength recovered to grade 5 (3 cases) and grade 4 (1 case). In 9 cases with spinal cord injury, 7 patients improved and 2 remained at the same ASIA level. CONCLUSIONS The main reasons for open surgery after percutaneous vertebroplasty and kyphoplasty were cement extravasation (the most common reason), puncture mistake, and false selection of indications.

A series of Lu3-xAl5O12:xCe3+ green phosphors with excellent morphology and high luminescence efficiency were prepared by adding different fluxes (H3BO3, NaF, and BaF2). The results show that fluxes do not affect the crystal structure but can improve the morphology and luminescence intensity. The optimum of H3BO3, NaF, BaF2 are 1.0 wt%, 15 wt%, 12 wt% and the luminescence intensity increased by 85%, 35%, 17% compare to the non-flux sample, respectively. The luminescence intensity and thermal stability of samples prepared by composite fluxes have been enhanced because of uniform particle size with nearly spherical morphology. The luminescence intensity of the sample prepared by 1.5 wt% H3BO3+15 wt% NaF is 88% higher than without adding flux, 1.0 wt% H3BO3+12 wt% BaF2 increased by 103%. Moreover, the luminescence intensity of the sample prepared by 1.5 wt% H3BO3+12 wt% BaF2 is 6% higher than non-flux at 200 °C. This has mainly been attributed to the significantly improved fluidity of high-temperature viscous reactions, the particles have the same growth trend in all directions, so the particle size and morphology of Lu3Al5O12:Ce3+ have been optimized. This study provides an effective strategy for improving the luminescence intensity and thermal stability of Lu3Al5O12:Ce3+.

We put forward an assessment system of thoracolumbar osteoporotic fracture (ASTLOF) evaluating the severity of thoracolumbar osteoporotic fracture. This study was to investigate its efficacy in guiding clinical practice.Three hundred and eighty-one patients with thoracolumbar vertebral osteoporosis fracture admitted to the hospital from January 2010 to December 2011 were enrolled in the study. All cases were evaluated by ASTLOF including evaluation of morphological changes, MRI, bone mineral density and pain. The patients were treated with different methods according to ASTLOF score. All patients were followed up on a regular basis. The treatment results were assessed by VAS and ODI.All patients were followed up with an average of 20.1 (range: 6-30) months. There were 91 cases of ASTLOF score4 points. Their average VAS score decreased from 8.0 ± 1.7 points to 2.0 ± 1.3 with statistical significance (P0.05) and the average ODI score decreased from 69.5 ± 2.8 to 38.1 ± 1.5 (P0.05). One hundred and thirty-two cases were with ASTLOF score=4, with the average VAS score decreased from 8.2 ± 1.4 to 1.9 ± 1.2 (P0.05) and the average ODI score decreased from 71.5 ± 3.7 to 36.2 ± 2.5 (P0.05). There were 158 cases of ASTLOF score ≥ 5, with the VAS score decreased from 8.0 ± 1.7 to 2.0 ± 1.3 and the ODI score decreased from 69.5 ± 2.8 to 38.1 ± 1.5.ASTLOF based on the severity of thoracolumbar osteoporotic fracture was suggested to be helpful in guiding clinical practice.

Modeling of induced polarization (IP) phenomena is important for developing effective methods for remote sensing of subsurface geology. However, the quantitative interpretation of IP data in a complex 3-D environment is still a challenging problem of applied geophysics. This letter develops a method of determining a 3-D distribution of the four parameters of the Cole-Cole model based on surface IP data. The method takes into account the nonlinear nature of both electromagnetic induction and IP phenomena. The solution of the 3-D IP inverse problem is based on the regularized conjugate gradient method. The method was tested on a synthetic model with variable dc conductivity, intrinsic chargeability, time constant, and relaxation parameters, and it was also applied to the actual 3-D IP survey data. We demonstrate that the four parameters of the Cole-Cole model, namely, dc electrical resistivity, chargeability, time constant, and the relaxation parameter, can be recovered from the observed IP data simultaneously.

Buck-IPT system is composed of a front power regulation buck circuit and a behind inductive power transfer circuit (IPT), which is higher-order, multi-operating-mode, compound nonlinear system. Aiming at dynamic problems such as large inductor current and slow response in the start-up progress, this paper proposes a dynamic characteristic optimization control method. Firstly, this paper proposes a reduced second-order time-varying model considering the inverter's equivalent load characteristic. And then, Based on this model, a sliding-mode control using the exponential reaching law is applied to optimize the start-up process of the Buck-IPT system. Finally, the simulation and experiment results have verified that the proposed method can realize good dynamic performance with fast response, limited-current of front inductor, no overshoot of front capacitor voltage.

TiO2 nanotubes have been extensively investigated in osseointegration and drug delivery due to their high porosity and large surface area. In this study, coatings with nanopore/nanotube porous composite structure were prepared on the surface of TC4 (Ti-6Al-4V) alloy plates by constant current anodization and secondary anodization; then, heat treatment was conducted under appropriate conditions. To understand the effect of heat treatment parameters on the related properties and subsequent applications, the as-formed nanotubes were characterized by scanning electron microscope, energy-dispersive X-ray spectroscopy, X-ray diffraction, Raman spectroscopy, potentiodynamic polarization and electrochemical impedance spectroscopy. Based on the characterization results, the widely accepted field-assisted dissolution equilibrium theory on the growth mechanism of nanotubes was questioned, and the oxygen bubble mould theory was applied as a reasonable explanation. It is concluded that 350 °C is a more suitable temperature for heat treatment while 550 °C tends to cause more distinct structural destruction of TiO2 nanotubes, consequently deteriorating the corrosion resistance in modified simulated body fluid. The nanopore/nanotube porous composite materials fabricated by this method are able to effectively promote bone regeneration and repair, showing their inherent potential for application in artificial implants.

A well-defined three-dimensional (3-D) reconstruction of bone-cartilage transitional structures is crucial for the osteochondral restoration. This paper presents an accurate, computationally efficient and semi-automated algorithm for the alignment and segmentation of two-dimensional (2-D) serial to construct the 3-D model of bonecartilage transitional structures. Entire system includes the following five components: (1) image harvest, (2) image registration, (3) image segmentation, (4) 3-D reconstruction and visualization, and (5) evaluation. A computer program was developed in the environment of Matlab for the semi-automatic alignment and automatic segmentation of serial sections. Semi-automatic alignment algorithm based on the position’s cross-correlation of the anatomical characteristic feature points of two sequential sections. A method combining an automatic segmentation and an image threshold processing was applied to capture the regions and structures of interest. SEM micrograph and 3-D model reconstructed directly in digital microscope were used to evaluate the reliability and accuracy of this strategy. The morphology of 3-D model constructed by serial sections is consistent with the results of SEM micrograph and 3-D model of digital microscope.

All-inorganic perovskites have gained considerable significance. Despite their superior thermal robustness, poor phase stability has rendered inorganic perovskites adverse. Herein, on the basis of first-principles calculations, we find that the incorporation of rubidium (Rb) and potassium (K) in an appropriate ratio will stabilize CsPbI2Br perovskites considerably, in which the cooperative interactions between Rb/K, I and Br play an important role. Besides, it is verified that 2D orthorhombic CsPbI3 with a thickness of ~1 nm exhibits outstanding stability, even exceeding the non-perovskite, yellow structure and has a suitable band gap for solar cell applications.

Our aim was to investigate the causes of and treatment strategies for surgical complications of thoracic spinal stenosis.Between May 1990 and May 2010, 283 patients with thoracic spinal stenosis were treated in our department. Three physicians were assigned to patient follow-up. Patient medical records and radiographs were reviewed. Complications were categorised as perioperative, mid- to long-term and donor-site.Follow-up was completed for 254 patients; 249 patients survived. Follow-up time ranged from one to 19 years, with a mean of six years and two months. There were 107 cases with complications an incidence rate of 42.1%. Eleven cases were pulmonary infection, seven transient nerve-root injury, three pulmonary injury and one vertebral canal haematoma, all of which resolved. Thirteen cases of spinal cord injury postoperatively were treated using dehydration and corticosteroid therapy; eight recovered to the preoperation level, and five deteriorated. Eleven cases resulted in dural injury, and four led to cerebrospinal fluid leakage. There were five cases of wound-fat liquefaction and one of wound infection. Seven cases with deep venous thrombosis of the lower limb resolved by elevating the affected limb and administration of low-molecular-weight dextran. Seven cases of delayed wound healing recovered following change of dressings and antibiotic administration. Four cases of delayed bone-graft fusion recovered by extending the external fixation time. One case of bone-graft absorption was treated by iliac bone grafting and bracing. Two cases of internal fixation breakage were treated by removing the internal fixation.Thoracic spinal stenosis surgery may result in various complications but has a good prognosis with proper treatment. The key points in reducing complications are the surgeon's familiarity with operative imperatives and the appropriate surgical approach.

Neuroblastoma (NB) is the most prevalent type of extracranial solid tumour in young children. To improve current understanding of the mechanisms, which modulate cancer cell proliferation, invasion and migration, investigations have focused on microRNAs (miRs), a class of small non‑coding RNAs, which post‑transcriptionally regulate gene expression during various crucial cell processes. The present study aimed to investigate the role of miR‑451 in NB. Human NB tissue and adjacent normal tissue were surgically removed, and the expression of miR‑451, and development and pathological characteristics of NB were investigated. The expression of miR‑451 was reduced in the NB tissue, compared with that in the adjacent tissue, and correlations between the reduction in miR‑451 and unfavourable variables included tumour size (P=0.0081), differentiation (P=0.0217), lymph node metastasis (P=0.0489), tumour‑node‑metastasis stage (0.0220) and distant metastases (P=0.0201). Transfection of the SK‑N‑SH and GI‑LA‑N NB cell lines with miR‑451 inhibited cell growth, invasion and migration. Furthermore, the present study demonstrated that macrophage migration inhibitory factor (MIF) was regulated directly by miR‑451 and was a critical mediator of the biological effects of miR‑451 in NB. The re‑expression of MIF markedly reversed the carcinogenic inhibitory property of miR‑451. These data provide a more detailed understanding of the essential role of miR‑451 in NB, which relies on regulation of the expression of MIF.

Short-segment U-shaped pedicle screw fixation has been widely used to treat thoracolumbar burst fracture. Some studies have reported the disadvantages of traditional U-shaped pedicle screw, which included a relatively high rate of adjacent segment degeneration and screw failure, including screw pullout and breakage. The purpose of this study was to assess the efficacy of open reduction and fixation using KumaFix fixation system in treatment of thoracolumbar burst fractures.From June 2011 to June 2012, 45 consecutive patients with thoracolumbar burst fractures were enrolled. They were randomly assigned to treatment with KumaFix (the treatment group, n = 23) or traditional U-shaped pedicle screw (the control group, n = 22). The patients were followed up postoperatively and were assessed with regard to radiologic and clinical outcomes. Radiologic outcomes were assessed mainly on the basis of Cobb angle and vertebral wedge angle. Clinical outcomes were evaluated mainly with use of Visual Analog Scale (VAS) for pain and the Oswestry Disability Index (ODI) Questionnaire.All patients were followed up from 9 to 22 months. There were no significant differences between the two groups with regard to preoperative indices. The operation time in the treatment group was significantly lower than that in the control group. Preoperative Cobb angles and vertebral wedge angles in two groups were significantly decreased after surgery, and these have been well maintained at the last follow-up with mild correction losses. The results of clinical outcome showed lower VAS and ODI scores in two groups compared with those preoperative, and the treatment group had greater improvement on the ODI compared with the control group at the last follow-up.Compared with traditional U-shaped pedicle screw, KumaFix fixation system can achieve gradual, controlled reduction, provide enough space for bone implantation, and avoid acceleration of adjacent segment degeneration. It is an effective and reliable technique to treat thoracolumbar burst fractures.

Previous studies have suggested that percutaneous vertebroplasty might alter vertebral stress transfer, leading to adjacent vertebral failure. However, no three-dimensional finite element study so far accounted for the stress distributions on different cement volumes. The purpose of this study was to evaluate the stress distributions on the endplate under different loading conditions after augmentation with various volumes of bone cement.L2-L3 motion segment data were obtained from CT scans of the lumbar spine from a cadaver of a young man who had no abnormal findings on roentgenograms. Three-dimensional model of L2-L3 was established using Mimics software, and finite element model of L2-L3 functional spinal unit (FSU) was established using Ansys10.0 software. For simulating percutaneous vertebral augmentation, polymethylmethacrylate (PMMA) was deposited into the bipedicle of the L2 vertebra. The percentage of PMMA volume varied between 15% and 30%. The stress distributions on the endplate of the augmented vertebral body were calculated under three different loading conditions.In general, the stress level monotonically increased with bone cement volume. Under each loading condition, the stress change on the L2 superior and inferior endplates in three kinds of finite element models shows monotonic increase. Compared with the stress-increasing region of the endplate, the central part of the L2 endplate was subject to the greatest stress under three kinds of loading conditions, especially on the superior endplate and under flexion.The finite element models of FSU are useful to optimize the planning for vertebroplasty. The bone cement volume might have an influence on the endplate of the augmentation, especially the superior endplate. It should be noted that the optimization of bone cement volume is patient specific; the volume of the bone cement should be based on the size, body mineral density, and stiffness of the vertebrae of individual patients.

STUDY DESIGN A prospective self-controlled study. OBJECTIVE The aim of the present study was to compare the application and clinical outcomes of transposterior arch lateral mass screw and lateral mass screw fixation of the atlas in the treatment of atlantoaxial instability. SUMMARY OF BACKGROUND DATA Atlas posterior screw fixation techniques comprise transposterior arch lateral mass screw fixation and lateral mass screw fixation. Previous studies have focused mainly on the feasibility of the anatomy and the biomechanics of the methods. METHODS From June 2006 to February 2011, 66 patients with atlantoaxial instability were randomly assigned for treatment with transposterior arch lateral mass screw or lateral mass screw fixation of the atlas, combined with axis pedicle screw fixation. Patients were followed up regularly. The operation time, blood loss, intraoperative complications, Japan Department of Orthopedics Association Score, visual analog scale score, and bone fusion rates were recorded. RESULTS The operation was successful in all 66 cases, with all patients showing improvement in clinical symptoms. There were significant differences in operation time and blood loss between the 2 groups (P

Disorders in occipitocervical region are difficult to treat. Complications often occur after fusion surgery and may be life-threatening in severe cases. This study is to investigate the causes and treatment strategies for the postoperative complications of occipitocervical fusion. Between May 1985 and May 2011, 316 patients with various occipitocervical diseases underwent occipitocervical surgery, with or without internal fixation. Two physicians were assigned for patients follow-up. Their medical records and radiographs were reviewed and the postoperative complications, including those at the occipitocervical region and donor site, were analyzed. Three hundred cases were followed up from 24 months to 26 years with an average of 9 years and 8 months, and the follow-up rate was 94.9 %. There were 16 cases with complications after surgery in the uninstrumented fusion group; the incidence was 33.3 %. These included 11 patients (22.9 %) with complications in occipitocervical region and five patients (11.9 %) with donor-site complications. 45 complications presented in the instrumented fusion group, the incidence was 17.9 %. These included 30 patients (11.9 %) with complications in occipitocervical region and 15 patients (5.9 %) with donor-site complications. Perioperative complications included vertebral artery injury, spinal cord injury, nerve root injury, suffocation, cerebrospinal fluid leakage, and infection. Mid- to long-term complications included bone-graft displacement or absorption, aggravated vertebral dislocation, improper screw placement, spinous process fracture, and internal fixation breakage. Donor-site complications were hematoma, pain and infection. The surgery of occipitocervical fusion carries a relative high risk for complications, especially if no instrumentation is used. The key points in reducing complications are the surgeon’s familiarity with the anatomy of occipitocervical region and the appropriate internal fixation.

A real time simulator for infrared scenes is required to evaluate the performances of recognition and tracking of information processing machine in seeker. A real time simulator for infrared scenes composed of two Intel i860 processors is described in the paper. We first describe the hardware architecture of our system, then we give out schematic diagram illustrating how to compute the image sequences of infrared scenes based on our hardware system. Finally, experimental results indicate that the simulator can meet the needs of application in practice.

We have developed a kind of magnetic reference technique and correction method(MRTC) in the 3D array data acquisition and processing of CSAMT. In this paper, firstly, the magnetic reference technique was put forward, which has facilitated the data acquisition of CSAMT. Secondly, details were given to show how the magnetic field correction method was to achieve, which guaranteed the accuracy of the calculation of Cagniard resistivity. Thirdly, model tests have been done for half space, layered-earth, and 3D models. And finally, field trial and MRTC data processing have been carried out. The results have showed that the MRTC in CSAMT improved the quality of apparent resistivity curve very much, the standard deviation of apparent resistivity has been controlled under 3% or less. This technique provides CSAMT with a great mobility and flexibility.

The problem and its resolvent about redundancy of co-linear points in estimating the fundamental matrix (FM) which is a basic tool in scene analysis are developed, based on the application in computer vision of epipolar geometry and perspective geometric invariants. The redundancy means that, on a line, there are at most three points that can be used as matching points to estimate the FM, the others are the redundant points. Its proof in theory and experimental results show that the accuracy and stability of FM are distinctly improved by eliminating the redundant points.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.