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Background/objective Brain metastasis in osteosarcoma (BMO) is rare and its clinical characteristics are often buried among studies on brain metastasis of bone and soft tissue sarcomas. The aim of the present study was to summarize the incidence, clinical characteristics, treatment and outcomes of patients with BMO. Methods This retrospective study included 7 patients with BMO who received treatment in our center between 2005 and 2019. The clinical medical records of the 7 patients, together with data of 70 BMO patients published in 33 articles and retrieved by means of PubMed and Medline, were analyzed, retrospectively. Results Data analysis of the 97 BMO patients showed a high correlation between the interval from the primary diagnosis to BMO occurrence and the interval from the primary diagnosis to prior metastases. Multivariate analysis showed that chemotherapy, radiotherapy and surgery were three main factors affecting the overall survival of BMO patients (HR = 0.427; HR = 0.372; HR = 0.296). Surgery combined with chemotherapy or radiotherapy offered a better overall survival than surgery alone. Conclusion Patients with BMO may obtain survival benefits from regular neuroimaging and early aggressive multi-disciplinary interventions including surgical resection, postoperative radiotherapy and chemotherapy. Synopsis This is a retrospective study describing the characteristics of metastasic intervals, locations, clinical features and prognosis in 97 patients with brain metastasis of osteosarcoma (BMO). Multivariate analysis showed that chemotherapy was effective as surgery and radiotherapy for the treatment of BMO. Our findings emphasize the importance of regular neuroimaging and early aggressive multi-disciplinary interventions including surgical resection, postoperative radiotherapy and chemotherapy.

In this work, the simulating analysis of PoP structure under the temperature range from 0 °C to 125 °C is carried out using direct thermal-cycle analysis and Coffin-Manson method. The results show that the maximum accumulating inelastic hysteresis energy appears on the solder ball in the bottom fine-pitch ball grid array (FBGA) structure. The thermal-fatigue crack initiates in the two symmetrical corners of solder ball in FBGA structure. The thermal-fatigue damage evolves fast in the outer row corner's balls then slowly propagates into the inner row balls in FBGA structure. By analyzing the failure data of solder balls, a thermal-fatigue failure criterion is defined where the critical failure probability value is about 80%.

Background: Intralesional excision with curettage is the standard method of giant cell tumor (GCT) treatment, but the ideal filling material after curettage remains controversial. The purpose of this study was to compare the oncological and functional outcomes which underwent cementation or bone grafting after GCT curettage around the knee. Methods: We reported 136 cases with GCTs in distal femur or proximal tibia who accepted curettage from five clinical centers during the last 15 years. All patients were divided into two groups according to filling materials. Recurrence-free survival proportions were used to evaluate oncological outcomes while the Musculoskeletal Tumor Society (MSTS) 93 functional score was used to evaluate functional outcomes. Other parameters including surgical complication, general condition, and radiological classification had been analyzed. The valid statisitical data was analyzed using SPSS 13.0 software. Results: After GCT curettage, 86 patients (63.2%) accepted bone grafting while 50 patients (36.8%) accepted cementation. There was no statistical difference in age, gender, tumor location, radiological classification, fixation, follow-up time, and MSTS 93 functional score between cementation group and bone grafting group. The recurrence-free survival proportions showed that the recurrence rate in bone grafting group was higher than it in cementation group (P = 0.034). Surgical complication was lower in cementation group than that in bone grafting group but without statistically significant difference (P = 0.141). Conclusions: Parameters including patients’ age, gender, tumor location, and radiological classification did not affect surgeons’ treatments in cavity filling after GCT curettage. Cementation should be recommended because of easy usage, the similar postoperative knee function with bone grafting, and the better local tumor control than bone grafting. Key words: Bone Grafting; Cementation; Giant Cell Tumor; Knee

According to the structure and production processing requirements of polyester filament winding head, a finite element dynamic model of the winding system in parameters time-varying was established. By using the method of numerical calculation, the dynamic characteristics of the winding head were analyzed in three processes: rapid starting-up in empty volume, winding filament process and stopping in full volume. By studying the influence of the three processing under large stiffness coupling and soft stiffness coupling in the winding head, the role of the coupling stiffness and spindle structure was revealed in different working process.

Modern planetary-scale online services have massive data to transfer over the wide area network (WAN). Due to the tremendous cost of building WANs and the stringent timing requirement of distributed applications, it is critical for network operators to make efficient use of network resources to optimize data transfers. By leveraging software-defined networking (SDN) and reconfigurable optical devices, recent solutions design centralized systems to jointly control the network layer and the optical layer. While these solutions show it is promising to significantly reduce data transfer times by centralized cross-layer control, they do not have any theoretical guarantees on the proposed algorithms. This paper presents approximation algorithms and theoretical analysis for the online transfer scheduling problem over optical WANs. The goal of the scheduling problem is to minimize the makespan (the time to finish all transfers) or the total sum of completion times. We design and analyze various greedy, online scheduling algorithms that can achieve 3-competitive ratio for makespan, 2-competitive ratio for minimum sum completion time for jobs of unit size, and 3α-competitive ratio for jobs of arbitrary transfer size and each node having degree constraint d, where α = 1 when d = 1 and α = 1.86 when d ≥ 2. We also evaluated the performance of these algorithms and compared the performance with prior heuristics.

In this article, the failure behaviors of different solder balls and arrays used in a commercial produce were investigated experimentally and computationally. The results indicated that the effect of different solder balls and arrays on the failure behavior of Package-on-Package (PoP) structure cannot be ignored. For example, the failure mechanism of a structure with 2 × 15 solder balls could be characterized as a deformation-cracking-delamination model under axially tensile loading, while as a deformation-instability model under three-point bending loading. The allowable deformation of the former is ten times larger than that of the latter. In addition, the failure behavior for a structure with different solder balls and arrays varies. It is strongly dependent on the stiffness of PoP structure, which is dominated by the number and array of the solder balls. The relationship between the stiffness and the number appears nonlinear. More specifically, there is the maximum value for a structure.

The paper presents a failure analysis of tower axle in the water tank wire drawing machine. Material of the tower axle is 40Cr steel. In order to analyze the failure reasons of tower axle in the water tank wire drawing machine, we take experimental means such as morphological analysis, mechanical property testing, micro-metallography and scanning electron microscopy (SEM) of fracture observation, etc. The results show that the fracture of tower axle belongs to brittle fracture. The content of inclusions is more, and the composition is complex in the material. The heat treatment technology is improper. Improper quenched and tempered processing technologies cause more reticular and blocky ferrite in the steel. These are the main reasons for fracture of the tower axle.

Failure behaviors of die and die attach adhesives for high integration and intensive 3-dimension stacked package device were carried out by using in-situ scanning electron microscope (SEM) in three-point bending tests and finite element (FE) analysis with the cohesive zone model. These experimental results indicated that the failure model consisted mainly of discontinuous cracks bridge-link pattern between the dies for the typical package on package (PoP) specimen, in which the discontinuous crack-bridging model for different fracture toughness of die attach adhesives was demonstrated by the mixed-model in the complex stress status. And the simulation results indicated also that the cohesive zone model (CZM) with an uncoupled bilinear traction-separation law (TSL) can characterize the fracture mechanism and discontinuous crack-bridging process of these samples. Some dominated parameters in the bilinear CZM could also qualitatively describe the damage initiation and evolution of cohesive elements. Therefore, the numerical and experimental results are in good agreement.

The dragonfly wing, which consists of veins and membrane, is of biological hierarchical material. We observed the cross-sections of longitudinal veins and membrane using Environmental Scanning Electron Microscopy (ESEM). Based on the experiments and previous studies, we described the longitudinal vein and the membrane in terms of two hierarchical levels of organization of composite materials at the micro- and nano-scales. The longitudinal vein of dragonfly wing has a complex sandwich structure with two chitinous shells and a protein layer, and it is considered as the first hierarchical level of the vein. Moreover, the chitinous shells are concentric multilayered structures. Clusters of nano-fibrils grow along the circumferential orientation embedded into the protein layer. It is considered as the second level of the hierarchy. Similarly, the upper and lower epidermises of membrane constitute the first hierarchical level of organization in micro scale. Similar to the vein shell, the membrane epidermises were found to be a paralleled multilayered structure, defined as the second hierarchical level of the membrane. Combining with the mechanical behavior analysis of the dragonfly wing, we concluded that the growth orientation of the hierarchical structure of the longitudinal vein and membrane is relevant to its biomechanical behavior.

This article presents design and measurement of a planar multiband (GSM850/900, DCS, PCS, and UMTS bands) antenna used in a laptop computer. The antenna can be identified by crossly connecting a meandered inverted-F configuration and a T-shaped monopole. The inverted-F part is mainly responsible for GSM-band operation. To cover the DCS, PCS, and UMTS bands, a T-shaped monopole is added. Although directly connecting them together, VSWR cannot meet the specification at the higher band. Therefore, an open-tub is added at bottom end of the T-shaped monopole. It is investigated that the stub serves as a capacitive match element. After tuning length of this stub, all properties of the pentaband antenna include the bandwidth, radiating pattern, and gain variation can satisfy practical applications. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:857–861, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25859

Lidar (Light detection and ranging) has special capabilities for remote sensing of many different behaviours of the atmosphere. One of the techniques which show a great deal of promise for several applications is Raman scattering. The detecting capability, including maximum operation range and minimum detectable gas concentration is one of the most significant parameters for lidar remote sensing of pollutants. In this paper, based on the new method for evaluating the capabilities of a Raman lidar system, we present an evaluation of detecting capability of Raman lidar for monitoring atmospheric CO2 in Hefei. Numerical simulations about the influence of atmospheric conditions on lidar detecting capability were carried out, and a conclusion can be drawn that the maximum difference of the operation ranges caused by the weather conditions alone can reach about 0.4 to 0.5km with a measuring precision within 30ppmv. The range of minimum detectable concentration caused by the weather conditions alone can reach about 20 to 35 ppmv in vertical direction for 20000 shots at a distance of 1 km on the assumption that other parameters are kept constant. The other corresponding parameters under different conditions are also given. The capability of Raman lidar operated in vertical direction was found to be superior to that operated in horizontal direction. During practical measurement with the Raman lidar whose hardware components were fixed, aerosol scattering extinction effect would be a significant factor that influenced the capability of Raman lidar. This work may be a valuable reference for lidar system designing, measurement accuracy improving and data processing.

By the aid of the international mining software SURPAC, a geologic database for a multi-metal mine was established, 3D models of the surface, geologic fault, ore body, cavity and the underground openings were built, and the volume of the cavity of the mine based on the cavity 3D model was calculated. In order to compute the reserves, a grade block model was built and each metal element grade was estimated using Ordinary Kriging. Then, the reserve of each metal element and every sublevel of the mine was worked out. Finally, the calculated result of each metal reserve to its actual prospecting reserve was compared, and the results show that they are all almost equal to each other. The absolute errors of Sn, Pb, and Zn reserves are only 1.45%, 1.59% and 1.62%, respectively. Obviously, the built models are reliable and the calculated results of reserves are correct. They can be used to assist the geologic and mining engineers of the mine to do research work of reserves estimation, mining design, plan making and so on.

Study design To develop a high-accuracy, easy-manipulated, and low-cost cervical pedicle three-dimensional locator for guiding cervical pedicle screw placement. Objectives To improve the safety of cervical pedicle screw insertion, simplify its manipulation, and offer safety guarantees in clinical application. Summary of background data Because of the complicacy of the anatomic structure of cervical pedicle, clinical application of cervical pedicle screw remained hard to popularize. And recent advances on cervical pedicle location did not simplify the manipulation of procedure significantly. Without aid of locator, distance and angle errors were difficult to control. So far, the only instrument for the location of pedicle "computer-assisted image-guided surgical system" is too expensive for clinical use. Furthermore, it has not yet been documented on location instrument for insertion of cervical pedicle screws. Methods The high-accuracy three-dimensional locator, made of stainless steel was designed to aid cervical pedicle nail placement. The cadavers were inserted nails under guidance of the locator that has been input the corresponding parameters collected from CT images. Results were evaluated by CT scans. Results A total of 90 nails were inserted into cervical pedicles, 90% of which were found right in the pedicles; 10% had pedicle cortex breaches. Parallel offset error of the locator in cross-sectional and lateral CT image that was 0.56 +/- 0.70 and 1.04 +/- 0.99; angular offset error was 1.69 +/- 2.41 and 6.54 +/- 7.08. Conclusion Three-dimensional locator of cervical pedicle and its localization technique achieved good results for individuated screws insertion into cervical pedicles, having such advantages as easy manipulation, high accuracy, and low cost. The system presented safety guarantee to the application and advanced the prevalence of pedicle techniques. Its principium and design were demonstrated feasible.

The main obstacle in developing chemical sensor is that most of chemical sensing materials lack satisfactory sensitivity and selectivity to the chemical objects. In recent year, a great amount of efforts in solving the problem have been made, for instance, by composing sensing array with different materials or pattern recognition based on artificial neural networks. These efforts, however, are quite limited due to the fact that the excitation signal on single or fixed frequency is not suitable for sensing elements with different optical characteristics. In this paper, a new pattern recognition method based on multi-sensor multi-spectrum is proposed. The multi-sensor is composed of the sensing array made by non-selective sensing material and excited by a continuous spectrum. As the continuous spectrum covers a relatively wide frequency scope, the sensor array can describe different optical characteristics and create abundant sensing information. The adaptive sampling procedure of the spectrum and data processing algorithms are also given for the universal pattern recognition. The experiment results show that the method proposed in this paper can reduce evidently the requirements on sensitivity and selectivity of the sensing materials and is thus helpful to the practical realization of the chemical sensor.

A new pure rotational Raman-lidar system for monitoring atmospheric temperature is presented. Instead of using the double grating monochromator, the system employs two high resolution spectral resolving channels,each of which is composed of a three-stage Fabry-Perot etalon combined with a filter with band width of 7nm. The transmitting light source is an injection-seeded Nd:YAG laser. This configuration can achieve a high rejection rate (10-10) to Mie-Rayleigh elastic scattering (at 532nm wavelength)，and has an extremely narrow receiving bandwidth (less than 10pm) for pure rotation Raman scattering of N2 with quantum numbers of ±6 and ±12 respectively. Therefore, the system effectively rejects the interference of background radiation and pure rotational Raman scattering of O2, and the measurement of daytime tropospheric temperature from a single Raman spectral line intensity ratio using the lidar system is made possible because of the narrow receiving bandwidth. The temperature measurement precision of this Raman-lidar is improved at the same time. At last, two_channels signals were simulated by using balloon-based sounding temperature profile. The simulation demonstrated the feasibility of this lidar for atmospheric temperature profile measurement.