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Purpose: This meta-analysis compared the clinical outcome of three-dimensional (3D) printing combined with open reduction and internal fixation (ORIF) to traditional ORIF in the treatment of acetabular fractures. Methods: We searched the Cochrane Library, PubMed, Embase, VIP database, CNKI, and Wanfang database with keywords “acetabular fracture”, “3D printing”, “three-dimensional printing”, “open reduction and internal fixation”, “Acetabulum”, “Acetabula” from January 2000 to March 2020. Two reviewers independently selected articles, extracted data, assessed the quality evidence and risk bias of included trials using the Cochrane Collaboration’ s tools and/or Newcastle–Ottawa scale. When the two analysts had different opinions, they would ask the third analyst for opinion. Randomized controlled trials or retrospective comparative studies of 3D printing combined with ORIF (3D printing group) versus traditional ORIF (conventional group) in the treatment of acetabular fractures were selected. The data of operation time, intraoperative blood loss, intraoperative fluoroscopy times, incidence of complications, excellent and good rate of Matta score for reduction, and excellent and good rate of hip function score were extracted. Stata14.0 statistical software was used for data analysis. Results: Altogether 9 articles were selected, including 5 randomized controlled trials and 4 retrospective studies. A total of 467 patients were analyzed, 250 in the conventional group, and 217 in the 3D printing group. The operation time in the 3D printing group was less than that in the conventional group and the difference was statistically significant (standardized mean difference (SMD) = −1.19, 95% CI: −1.55 to −0.82, p 0.05). There was no significant difference in the excellent and good rate of hip function score at the end of postoperative follow-up between the two groups (OR = 0.84, 95% CI: 0.46–1.56, p > 0.05), but the follow-up time varies from 6 months to 40 months. Conclusion: Compared with traditional ORIF, 3D printing combined with ORIF has certain advantages in terms that 3D printing not only helps surgeons to understand acetabular fractures more intuitively, but also effectively reduces operation time, intraoperative blood loss, intraoperative fluoroscopy times, and postoperative complications. However, there were no significant differences in the excellent and good rate of Matta score for reduction and the excellent and good rate of hip function score at the end of follow-up.

A quasi-counter flow parallel-plate three-fluid membrane contactor with cooling tubes installed in the solution channels (QCPMCC) is used for air/solution/water exchange. The air and the solution streams are separated by the selectively permeable membranes. Absorption heat generated in the solution can be taken away by the water flow in the cooling tubes. A three-dimensional mathematical model describing the heat and mass transports in the membrane contactor is built based on an element including a piece of the plate membrane, half of the air channel, half of the neighboring solution channel, and half of the row of the tubes. The momentum, energy and mass conservation equations are simultaneously solved. The mean product of friction factor and Reynolds number (fRe)m, Nusselt number and Sherwood number under the conjugate heat and mass transfer boundary conditions are then obtained. Effects of the tube numbers, tube outer diameters, Reynolds numbers, and various tube shapes on the basic data are analyzed. It can be found that both the tube numbers and the tube outer diameters have small influences on the mean Nusselt numbers and Sherwood numbers for the air stream, while they have large effects on those for the solution stream.

A quasi-counter flow parallel-plate membrane contactor (QCPMC) has been applied for liquid desiccant air dehumidification. The air stream flows straightly in the rectangular channels, while the liquid desiccant (salt solution) flows in the side in and side out channels. The concept is similar to an air-to-liquid heat and mass exchanger where the air and the solution streams are separated by the selectively permeable membranes. The air is dehumidified by the water vapor transport from the air stream across the membranes into the solution side, while the solution is prevented from permeating through the membranes. A three-dimensional mathematical model describing the heat and mass transports in the membrane contactor is built based on an element including a piece of the membrane, half of the air channel, and half of the solution channel. The momentum, energy and mass conservation equations are simultaneously solved. The average product of friction factor and Reynolds number (fRe)m, Nusselt number (Num) and Sherwood number (Shm) under the conjugate heat and mass transfer boundary conditions are then obtained. Effects of the length-height ratios (x0/H), length-width ratios (x0/y0), entry ratios (xin/x0), and flow arrangements (quasi-counter, counter, and cross-flow) on the (fRe)m, Num and Shm are analyzed. It can be found that the length-height ratios (x0/H) have relatively more obvious influences on these basic values of the QCPMC.

Severe heat stroke (HS) consists of extreme hyperthermia with thermoregulatory failure, leading to high morbidity and mortality. Liver injury is a complication of HS that is associated with inflammatory responses and Kupffer cells (KCs), which are resident macrophages in the liver that serve as a major source of inflammatory cytokines; however, the association and the underlying mechanisms of KC functions in HS-induced endotoxemia and inflammation require an improved understanding. The important chemokine macrophage inflammatory protein-1α (MIP-1α) increases inflammatory responses and the secretion of inflammatory molecules from KCs, including tumor necrosis factor-α, interleukin (IL)-1β and IL-6. In addition, the activation of c-Jun N-terminal kinase (JNK) signaling is responsible for the development of liver inflammation. Therefore, HS animal and cell models were constructed in order to investigate the pathways involved in the HS-induced dysfunction of KCs. The results of the present study suggest that JNK may be involved in the MIP-1α-associated pathogenesis of KCs in HS injury.

In this study, the effect of wheel speed and mischmetal (MM) content on the magnetic properties of MMFeB ribbons was investigated. The samples were prepared via direct solidification technique. The nominal composition of the alloy ingots is MM x Fe92−x B8 with x varying from 9 to 15 in steps of 2. Experimental results show the overall magnetic properties of the ribbons. Analysis of the results shows that the magnetic properties first improve and then degrade with the wheel speed and MM content increasing. Increase in MM content leads to better formation of crystal texture in the ribbons, indicating that the α-Fe phase might undermine the formation of crystal texture. Magnetic properties results show that the coercivity of the ribbons rises with an appropriate increase in both MM content and wheel speed during melt-spun process. The strongest magnetic properties of the ribbons (remanence of M r = 0.72 T, intrinsic coercivity of H cj = 352.58 kA·m−1, and maximum energy product of (BH)max = 72.14 kJ·m−3) are obtained for compositions where x = 13 and a wheel speed of v = 20 m·s−1. The variation in maximum remanence (M r), coercivity (H cj), and maximum energy product ((BH)max) values were analyzed as a function of wheel speed for the MM13Fe79B8 melt-spun ribbons. All of the ribbons’ magnetic properties (M r, H cj, and (BH)max) first increase as the wheel speed increases up to 20 m·s−1 and then decrease gradually. The best magnetic properties are obtained at a wheel speed of 20 m·s−1, achieving M r value of 0.72 T, H cj value of 352.58 kA·m−1, and (BH)max value of 72.14 kJ·m−3.

Crowned dens syndrome(CDS) is a major imaging manifestation of "coronary" calcified deposits around the odontoid, with pain, stiffness, fever, and even cervical cord compression in the upper head and neck. It was first described by Bouvet et al. in 1985, and the onset was generally thought to be caused by crystal deposition. The clinical manifestations of CDS are often similar to meningitis and often accompanied by an increase in inflammatory markers in the blood. As a result, it is very easy to obtain missed diagnosis and misdiagnosis, and it is clinically prone to obtain wrong or unnecessary treatment. At present, the diagnosis of CDS is based on the imaging findings in CT as a "golden standard". NASIDs drugs and corticosteroids are the main treatment. The prognosis is also generally good, and the imaging findings of the patients with the disease disappear completely within 3 months.

By fieldwork, this paper analyzed the distribution feature of soil particles and its mechanism on the platform gardern in South Fujian, the results showed that the deeper to the earth, the bigger the soil particles were, and the soil particles became bigger with the surface became higher and steeper, style of cultivation and plants had close relation with the soil particles size at the same time. Applying organic fertilizer and taking reasonable land use pattern are presented to improve the soil particle structure and rural urbanization finally.

In this thesis, we take SH79F32 as main chip, the ultrasonic sensor of HC-SR04 as collection tools, wireless transceiver based on nRF905 as communication tool, and reach the function of wireless sensor networks. Through Altium DXP-2004 to conduct schematic design and draw PCB, and then solder circuit boards, use the software of Keil to design process, to realize wireless ultrasonic sensor communication between different microcontrollers, after that, complete the design and production of wireless ultrasonic sensor design and production.

This paper is about a kind of instrument which can detect the fault object by acoustic sensor detecting the object Surface acoustic signals, through the analysis of the acoustic signal of the intensity and frequency content, so determining the object if abnormal conditions occur. Design by using Piezoelectricity material as the sensing head, the signal processing circuit is based on SH79F32 microcontroller as the core, the single-chip microcomputer, integration with ADC, the analog signal from the sensor to convert them into digital signals, in the procedure, carries on processing to the signal frequency components, filter out low-frequency components, acoustic signal was finally measured on a screen display. including hardware design, production, processing, software programming, to obtain the acoustic fault detector, and to test its performance, results show successful.

This paper, based on STM32 and nRF905 wireless module, introduces a wireless temperature gathering and transmitting system. From RF modules and master control module, the hardware platform has been designed, beyond that, the paper introduces the temperature sensor network software design. The test show that the system is stable, and datas are reliable.

The wireless sensor network (WSN) is the development trend of the technology of sensor. This paper, based on the nRF905 wireless module, introduces a wireless temperature gathering and transmitting system. From RF modules and master control module, the hardware platform has been designed, beyond that, the paper introduces the temperature sensor network software design. The test show that the system is stable, and data are reliable.

Resonance light scattering (RLS) technique was applied to study macromolecular entanglements in highly dilute poly(vinyl methyl ether) (PVME)/poly(ethylene oxide) (PEO) solution during phase transition process. Temperature dependences of RLS intensities of PVME, PEO and PVME/PEO solutions were recorded. In addition, simulated temperature dependence of RLS intensity of PVME/PEO solution was drawn supposing there was no interaction between PEO and PVME. Comparison between the measured with the simulated results indicated that there were obvious differences in RLS intensities and transition temperatures. The present work proved the existence of entanglements during phase separation in highly dilute solution. Moreover, a model was proposed to describe the entanglement behavior.

The wireless sensor network (WSN) is the development trend of the technology of sensor. This paper, based on the nRF905 wireless module, introduces a wireless temperature gathering and transmitting system. From RF modules and master control module, the hardware platform has been designed, beyond that, the paper introduces the temperature sensor network software design. The test show that the system is stable, and datas are reliable.

The wireless sensor network (WSN) is the development trend of the technology of sensor. This paper, based on the nRF905 wireless module, introduces a wireless temperature gathering and transmitting system. From RF modules and master control module, the hardware platform has been designed, beyond that, the paper introduces the temperature sensor network software design. The test show that the system is stable, and datas are reliable.

Based on the object's polarization effects, polarization is a newly emerging method in the field of remote sensing. Both objects and atmosphere have polarization effects, however, the atmosphere's polarization effects are much stronger than that of objects'. Consequently, atmosphere polarization effects will interfere or even cover objects' when observing with sensors. How to maximally eliminate the polarized effects generated by the atmosphere is a crucial problem in polarization remote sensing. Atmospheric neutral point is an area where the degree of atmosphere polarization is near to zero; therefore, if sensors are set up in this area, atmosphere polarization would be greatly eliminated, which is the main content of separating the effects between objects and atmosphere by its neutral point method. In this paper, after processing and analyzing the experimental data got from the first polarization remote sensing flight experiment with atmosphere neutral point, the degree of polarization images captured in neutral and non-neutral point area were obtained, and it can be seen that the main value of polarized degree of images got in neutral point area was obviously smaller than that in non-neutral point area. The results showed that the theory mentioned above was logical and practical. An innovation in our study is that the requirements needed in polarization remote sensing flight with neutral point were clarified. In the meantime, a qualitative conclusion was drawn that observing with longer wavelength is more applicable to polarization remote sensing.

Cardiac troponin-I (cTnI) is one of the three regulatory subunits of the cardiac troponin which has the high sensibility and specificity of responding to myocardial injury. Studies have demonstrated that cTnI is released into the blood stream within hours following acute myocardial reperfusion injury. The clinical utility of cTnI for the assessment of myocardial damage is that it is more specific than creatine kinase MB (CKMB). This study investigated cTnI as a sensitive marker of myocardial reperfusion injury and its clinical value on beating heart surgery with right sub-axiliary incision.From December 2002 through December 2004, 100 patients with atrial septal defect (ASD), ventricular septal defect (VSD), atrial septal defect and ventricular septal defect (ASD + VSD), and tetralogy of Fallot were randomly divided into two groups: the treatment group (n = 50) was operated on with a beating heart under extracorporeal circulation (ECC), and the control group (n = 50) on an conventional arresting heart under ECC. The two groups both used a right sub-axillary incision. Blood samples from a central venous catheter (CVC) were collected before, at the end of aortic clamping, immediately after discontinue cardiopulmonary bypass (CPB), 3, 6, 24, and 48 hours after operation. The Abbott Axsym system with hol-automation fluorescent immunity analyzer was used for the quantitative determination of cTnI. cTnI was detected to investigate the effect of myocardial ischemia reperfusion injury and the clinical value of beating heart surgery with right sub-axillary incision.There were no significant differences between the two groups before operation. At the end of aortic clamping and thereafter, cTnI significantly increased in both groups, and reached the peak point at 6 hours after operation. At all the tested points, cTnI was significantly higher in the control group than the beating heart group (P0.05), especially at 6 hours post operation (P0.01). The operating time and ECC duration were shortened and the dosage of dopamine was decreased, when compared with the control group.There was less cTnI measured in the beating heart group than in the control group after CPB, demonstrating that beating heart surgery may significantly reduce myocardial reperfusion injury.

Art design is an important component of human civilization. With the computer aided design technology being used universally in art designs, educators are facing challenges as well as opportunities. Computer based technology has profoundly impacted art design education and has greatly stimulated designers' creative thinking. Traditional art deign education must accommodate this digitalized approach. Educators must help students to become proficient in computer skills, and most importantly to obtain extensive professional knowledge and to enhance aesthetic skills.