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81.
Objective: The focus of this study was to develop and optimize in situ implant formulation of meloxicam by quality by design (QbD) principle for long-term management of musculoskeletal inflammatory disorders.

Methods: The formulation was optimized by Box–Behnken design with polylactide-co-glycolide (PLGA) level (X1), N-methyl pyrrolidone level (X2) and PLGA intrinsic viscosity (X3) as the independent variables and initial burst release of drug (Y1), cumulative release (Y2), and dissolution efficiency (Y3) as the dependent variables. The formulation was physicochemically characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and powder X-ray diffraction (PXRD). Pharmacokinetic studies of the optimized formulation were performed on Sprague--Dawley rats.

Results: Y1 was significantly affected by X2 and X3. Y2 was affected by X1 and X3 while Y3 was affected by all three independent variables employed in the formulations. Responses for the optimized formulation were in close agreement with the values predicted by the model. SEM photomicrographs indicated uniform gel formulation. No chemical interaction between the components of formulation was observed by FT-IR and meloxicam was found to be present in the amorphous form in the gel matrix as revealed by PXRD. The maximum plasma concentration (Cmax), time to achieve Cmax and area under plasma concentration curve were significantly different from those of the solution formulation used as the control. Plasma concentration of meloxicam was maintained above its IC50 concentration required for COX-2 inhibition for 23 days.

Conclusion: Meloxicam in situ implant may provide long-term management of inflammatory conditions with improved patient compliance and better therapeutic index.  相似文献   

82.
光耦合器是具有绝缘安全性及在输入和输出之间实现电气信号隔离功能的器件,其绝缘和噪声抑制特性来自于采用的机械结构和材料。  相似文献   
83.
The last five to ten years have brought a technology-explosion in research and development of the printed circuit board (PCB). The great challenges for PCB producers have been the introduction of laser drilling and the required design-guidelines for 100 µm line and space as well as the frequent application of “state of the art” ball grid arrays (BGA) with 800 µm array pitches. The rapid development of semiconductor components resulted in smaller grid dimensions, which has been another challenge for the PCB makers. The reduction of the grid dimensions from 800 µm to 500 µm has been a big step for the PCB fabrication. However, the current degree of miniaturization even requires the transition to a 75 µm-technology. The line and space widths become ever more critical, and smaller grid dimensions require smaller laser drilled holes. Thereby the demands on the circuit carrier increase dramatically. Primarily base materials and registration techniques must be improved essentially to be able to produce these carriers with high yield and competitive costs. The usage of big production panel formats will be essential in the price war. Based on the state of the art, the aim of this contribution is to give the reader details on AT&S experiences and objectives of the establishment of new technologies. In particular, process steps such as registration, solder mask, conductor layer and base material structuring, laser and mechanical drilling as well as future surface finishing approaches are emphasized.  相似文献   
84.
We present first-principles calculations on SmCo5 using the self-consistent full-potential linearized augmented plane wave (FPLAPW) method. We systematically study the effect of considering the spin–orbit coupling and Coulomb correlations in the Sm f shell on the magnetic properties, electronic structure and spin-density maps. The calculated magnetic moment and magnetocrystalline anisotropy are in good agreement with experimental values when the LDA + U + SO scheme is used. This confirms the adequacy of using this scheme in SmCo5. The spin-density maps in the (0 0 1) plane show that the effect of the spin–orbit coupling on the spin-density structure of Sm atoms is stronger than that of Coulomb correlation. The reverse however, is true for Co atoms. We also study the influence of the magnetization direction on the energy bands through comparing the features of band structure when magnetization direction is along or perpendicular to the c-axis.  相似文献   
85.
Seven water and sediment samples were collected and tested for decolorizing crystal violet. Pseudomonas aeruginosa was the most effective isolate for dye decolorization. The LC50 of the crystal violet (115 mg/l) was measured using Artemia salina as a biomarker. The effect of different heavy metals on crystal violet decolorization was investigated. Cd2+ and Fe3+ ions showed marginal enhancement of the decolorization process, the rate was 1.35 mg/l/h compared to (1.25 mg/l/h) for the control. Phenol and m-cresol showed no effect on crystal violet decolorization, meanwhile p-cresol and p-nitrophenol reduced the decolorization rate to 1.07 and 0.01 mg/l/h, respectively. P. aeruginosa cells were immobilized by entrapment in agar-alginate beads. The beads were cultivated and reused in Erlenmeyer flask and in an air bubble column bioreactor and they enhanced the crystal violet decolorization rate to 3.33 and 7.5 mg/l/h, respectively.  相似文献   
86.
This paper explores numerical and experimental studies on the performance of a pneumatic conveying dryer. The four-way coupling Eulerian–Lagrangian approach is utilized in the numerical study and the experimental study is carried out in a pilot-scale vertical pneumatic conveying dryer of diameter 8.1 cm and 4.5 m length. The effects of Reynolds number, particle size, solid mass flow rate, and inlet gas temperature on the dryer performance are investigated. It is found that the present model predictions agree well with the experimental data. Generally, it is concluded that the drying rate increases as the Reynolds number increases, while increasing the particle size or the solid mass flow rate decreases the drying rate.  相似文献   
87.
In the Advanced Video Coding (AVC) standard, motion estimation (ME) adopts many new features to increase the coding performances such as block matching algorithm (BMA), motion vector prediction (MVP) and variable block size motion estimation (VBSME). However, VBSME is utilized in the MPEG4-AVC/H.264 standard which leads to high computational complexity and data dependency that make the hardware implementation very complex.  相似文献   
88.
The three cationic surfactants based on Schiff base were laboratory prepared, (E)-decyl-4-[(2-hydroxyethylamino) methyl]-N,N-dimethyl benzenaminium bromide (I), (E)-dodecyl-4-[(2-hydroxyethylamino)methyl]-N,N-dimethyl benzenaminium bromide (II) and (E)-hexadecyl-4-[(2-hydroxyethylamino)methyl]-N,N-dimethyl benzenaminium bromide (III) were evaluated as corrosion inhibitors for carbon steel in acid medium and antimicrobial agents against sulfate reducing bacteria, SRB. Three techniques were used for the corrosion inhibition evaluation, namely; weight loss, polarization and electrochemical impedance. The serial dilution method was used to evaluate the inhibiting effect of these compounds on the sulfate reducing bacteria growth. The results showed that the prepared compounds have good antimicrobial activities against the SRB as well as they have high efficiency as corrosion inhibitors for carbon steel in 1 M HCl.  相似文献   
89.

   

We present a fabrication process of low-cost superlattices and simulations related with the heat dissipation on them. The influence of the interfacial roughness on the thermal conductivity of semiconductor/semiconductor superlattices was studied by equilibrium and non-equilibrium molecular dynamics and on the Kapitza resistance of superlattice's interfaces by equilibrium molecular dynamics. The non-equilibrium method was the tool used for the prediction of the Kapitza resistance for a binary semiconductor/metal system. Physical explanations are provided for rationalizing the simulation results.  相似文献   
90.
A continuous evolution of business process parameters, constraints and needs, hardly foreseeable initially, requires a continuous design from the business process management systems. In this article we are interested in developing a reactive design through process log analysis ensuring process re-engineering and execution reliability. We propose to analyse workflow logs to discover workflow transactional behaviour and to subsequently improve and correct related recovery mechanisms. Our approach starts by collecting workflow logs. Then, we build, by statistical analysis techniques, an intermediate representation specifying elementary dependencies between activities. These dependencies are refined to mine the transactional workflow model. The analysis of the discrepancies between the discovered model and the initially designed model enables us to detect design gaps, concerning particularly the recovery mechanisms. Thus, based on this mining step, we apply a set of rules on the initially designed workflow to improve workflow reliability. The work presented in this paper was partially supported by the EU under the SUPER project (FP6-026850) and by the Lion project supported by Science Foundation Ireland under Grant No. SFI/02/CE1/I131.  相似文献   
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