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Based on the large eddy simulation (LES) and Lighthill acoustic analogy (LAA) methods, a hybrid simulation technique, so-called LESâ–“LAA, for improving wind buffeting noises generated by opening rear windows of a running vehicle is presented in this article. The wind buffeting noises are simulated by the LESâ–“LAA and experimentally verified. Some factors affecting the wind buffeting noise, such as vehicle speed and window opening scale, are investigated. To decrease the wind buffeting noises, some attempts are made by attaching absorption materials in the compartment and mounting a plexiglass baffle at an appropriate position for reducing wind noise. The results show that the calculation errors on the sound pressure level (SPL) of the LESâ–“LAA are less than 2%. The SPL of wind noise reaches a maximum value at a rear-window opening scale of 42% and is positively correlated to the vehicle speed. The wind buffeting noise of opening windows on both sides is lower than that of opening one. After mounting the baffle, the reduction of interior noise reaches to 27.26 dB. A conclusion is drawn that the proposed LESâ–“LAA method and the buffeting noise control measures are accurate, effective and feasible, which may be directly applied to vehicles and have potential for solving other aeroacoustic engineering problems.

With large-scale construction of landfills, the study of the properties of municipal solid waste (MSW) has become an important subject. The objective of this study is to propose a new constitutive model for MSW considering the effect of biodegradation. The indicators representing the degree of biodegradation are first discussed, and the impact of biodegradation on the mechanical properties of MSW is then formulated in volumetric strain by introducing a biodegradation-induced void change parameter, which provides a fundamental understanding of the change in waste properties with long-term biodegradation. On the basis of this, a constitutive model is developed following the framework of critical state soil mechanics, and the proposed model is validated by comparing simulations and experimental data of triaxial tests and of a long-term settlement experiment. Finally, the effects of MSW composition and biodegradation are analysed by parametric studies.

To investigate the changes in cell autophagy and the molecular mechanism of rapamycin affecting the fracture healing.Sprague-Dawley (SD) rats were used to establish the right femoral shaft fracture models, and then underwent immunofluorescence assay to detect the autophagy level in bone tissues. After model establishment, SD rats were divided into two groups, the control group and the rapamycin group (1 mg/kg/d). Respectively, at the 2nd, 4th, and 6th week, rats were randomly selected from each group for X-ray and Micro-computed tomography (Micro-CT) examinations to determine callus growth, immunofluorescence assay to detect the protein expression of light chain 3 II (LC3 II), immunohistochemistry to evaluate the autophagy level through detecting the expression of Beclin1 in rats, Western blotting assay to detect cell apoptosis in tissues, hematoxylin and eosin staining (HE staining) to evaluate the osteoblastic activity through count of osteoblast in bone tissue at the end of fracture, and measure the expression of vascular endothelial growth factors (VEGF).Significant increases were seen in protein expression of cells in bone tissues at the end of fracture. In rapamycin group, callus formation and calcification level in rats were all higher than those in control group; compared with control group, for rats in rapamycin group, cell autophagy was significantly elevated in bone tissues, while cell apoptosis at the end of fracture was reduced with a significant increase in osteoblastic activity. The expression of VEGF in rapamycin group was higher than that in control group.Rapamycin can facilitate fracture healing through inducing cell apoptosis and suppressing cell apoptosis in bone tissues.

To explore the safety and efficiency of transvaginal surgical treatment of cesarean scar pregnancy (CSP).A retrospective analysis of 54 CSP patients that received treatment in our hospital from October 2011 to September 2015 was performed, dividing two groups: Group A (n=34) received transvaginal cesarean scar pregnancy focus clearance surgery while Group B (n=20) received transcervical resection following methotrexate/mifepristone-combined treatment. The basic clinical findings were collected and analyzed, along with the curative effects between the two groups.Differences in age (30.91 ± 4.59 years vs. 31.91 ± 5.53 years) for gravidity (2.97 ± 1.24 times vs. 2.75 ± 1.48 times), cesarean section (1.24 ± 0.43 vs. 1.20 ± 0.41), time interval from last cesarean section (56.53 ± 32.93 months vs. 58.70 ± 39.44 months), menelipsis (51.35 ± 10.90 days vs. 57.85 ± 16.62 days), pre-operative serum-hCG (27953.65 ± 37517.10 mIU/L vs. 17368.24 ± 35094.14 mIU/L), operation time (43.34 ± 12.38 min vs 40.07 ± 16.88 min), menstruation recovery time (1.23 ± 0.53 months vs. 1.55 ± 0.76 months) were not statistically significant (p0.05). The differences in the intraoperative blood loss (43.34 ± 12.38 ml vs. 40.07 ± 16.88 ml), average hospital stay (7.61 ± 2.47 days vs. 12.42 ± 3.64 days), time for β-hCG to return to normal (18.50 ± 8.19 mIU/L vs. 29.00 ± 12.96 mIU/L) between the two groups were statistically significant (p0.05). Group A was significantly lower than Group B.Transvaginal surgery is an effective and relatively safe treatment option for CSP patients.

Broad infrared emissions at 1131, 1107 and 1291 nm were observed in the bismuth doped aluminosilicate glasses under 532, 690 and 808 nm excitation respectively. The origin of the broadband infrared luminescence was investigated in the aluminosilicate glasses. Based on the energy matching conditions, it is suggested that the infrared luminescence centres might be Bi1+ ions and BiO molecules. The broadband infrared luminescent characteristics of the glasses indicate that they are promising for broadband optical fibre amplifiers and tunable lasers.

Geographic information systems (GIS) have been widely used to study spatial variability in different atmospheric processes. In this study, we used a GIS approach to explore the potential to examine variation patterns of lightning strikes at different scales so that micro-, synoptic-, and planetary-scale processes can be linked in explaining and modeling the distribution patterns of lightning strikes. The data collected by the ground-based lightning detection system for an entire month in the western United States were used as an example. Lightning strike density surfaces were generated using different kernel bandwidths, or search radii. It has been recognized that density surfaces are useful in visual interpretation of spatial patterns at different scales, but there are insufficient data on how well such surfaces can be used in quantitative analysis of point distribution patterns. In our study, the resulting surfaces were compared quantitatively with gridded lightning strikes using meshes, or fishnets, of different cell sizes. The fishnet cell sizes ranged from 1 km for micro-scale processes to 50 km for synoptic- and planetary-scale processes. The results suggest that there is a threshold in the search radius or kernel bandwidth, above which a significant amount of errors would be introduced in quantitative analysis. It could be argued that it is possible to achieve a balance between the need for visual interpretation of distribution patterns and the need for quantitative analysis at different scales. We used the lightning data of August 1990 and digital elevation models of 1 km resolution to perform a case study on the relationship between lightning occurrence and topography. Our results indicate that at different spatial scales, the relationships between lightning density and topography may reflect different processes that influenced the spatial distribution pattern of the lightning occurrence.

Multiparous early lactation Holstein cows (n = 16) were used in a randomized complete block design to determine the effects of feeding fatty acid calcium and the interaction of forage quality on production performance and biochemical indexes in early lactation cow. Treatments were as follows: (i) feeding low-quality forage without supplying fatty acid calcium (Diet A), (ii) feeding low-quality forage with supplying 400 g fatty acid calcium (Diet B), (iii) feeding high-quality forage without supplying fatty acid calcium (Diet C) and (iv) feeding high-quality forage with supplying 400 g fatty acid calcium. This experiment consisted 30 days. The milk and blood samples were collected in the last day of the trail. Intakes were recorded in the last 2 days of the trail. Supplementation of fatty acid calcium decreased significantly dry matter intake (DMI) (p < 0.01). Addition fatty acid calcium decreased milk protein percentage (p < 0.01) and milk SNF percentage (p < 0.01), but increased MUN (p < 0.05). Supplemented fatty acid decreased concentration of blood BHBA (p < 0.05), but increased TG, NEFA, glucagon, GLP-1, CCK, leptin, ApoA-IV, serotonin and MSH concentration in blood, the CCK concentration and feed intake showed a significant negative correlation (p < 0.05).

To study the effects of acute hypoxia and intermittent hypoxic acclimatization on cardiac systolic and diastolic functions in rats.Cardiac functions were investigated after intermittent hypoxic acclimatizated (3000 m and 5000 m, 2 wk respectively, 4 h/d) and normoxic rats were exposed to hypoxia (8000 m) for 4 h.The systolic functional parameters such as LVSP, +dp/dtmax, Vpm, Vmax and the diastolic functional parameter -dp/dtmax of acute hypoxic rats were reduced significantly as compared with normoxic control rats. After hypoxic acclimatization, the left ventricular functions of rats were increased significantly as compared with those of acute hypoxic rats. But they were still lower than those of normoxic control rats.Acute hypoxia can affect cardiac functions and hypoxic acclimatization can alleviate the hypoxic effects on cardiac functions.

To observe the preventive and therapeutic effects of gangliosides on acute altitude hypoxic brain damage.Fifteen Wistar rats, weighed 180-220 g, were randomly divided into 3 groups, hypoxia group A, hypoxia group B and normoxia group. The rats in hypoxia group A were exposed to a simulated altitude of 7000 m for 5 hours and the rats in hypoxia group B were exposed to hypoxia after intraperitoneal administration of mixed gangliosides (100 mg/kg/d) for 3 days.Gangliosides could ameliorate the severity of damage in neuronal bodies, cellular skeletons and synapses, especially in synapses.It is suggested that gangliosides are effective in preventing and treating hypoxic brain damages by decreasing the accumulation of intracellular Ca2+, and stabilizing CaM and CaM PKII activity during acute hypoxia.

To correlate the injury of vascular endothelial cells during various pathological conditions with the change of vWF (von Willebrand Factor) in different VEC lines.Flow cytometer(FCM) were used to defect the immunoflourescent stained vWF in pulmonary artery endothelial cells (PAEC) of pig and aortic endothelial cells(AEC) of rats.The positive rates of vWF in PAEC of pigs is similar with that in AEC of rats under normal condition, but it decreased differently after hypoxic or cold injury. It was very interesting that the mean fluorescence intensity of positive PAEC or AEC exposed to hypoxia or cold elevated significantly compared with those of control.The change of vWF in VEC can be used to evaluate the function of VEC under different stress.

Until recently, China had been isolated from Western countries for almost 30 years. Surgeons of Western countries, perhaps, are interested to know what is happening in surgery in China. This communication reviews the current interests in Chinese surgery. It is by no means complete, nor is that the intention. The intention is to introduce to our foreign colleagues a general overview of some highlights in Chinese surgery.

The findings from dissections, injection studies, and angiograms of 180 specimens of the anterior portion of left and right iliac crests taken from 90 cadavers are reported. These findings suggested that the deep circumflex iliac vessels were suitable for use as a nutritive pedicle in microvascular free transfer of iliac bone. Therefore, the technique of microvascular free transfer of iliac bone based on these vessels was developed and applied clinically in 2 cases with good results. The advantages and disadvantages of using the superficial circumflex iliac vessels or the deep circumflex iliac vessels as the vascular pedicle for iliac grafts also are discussed.

The findings from dissection, injection studies, corrosion specimens, and angiograms in 300 specimens of the iliogluteal region taken from 150 cadavers are reported. These findings suggest that the deep superior branches of the superior gluteal vessels may serve a nutritive pedicle in microvascular free transfer of iliac bone. Therefore, the operative technique has been developed and applied clinically with good results. The selection of different vessels as a nutritive pedicle for the free transfer of iliac bone is discussed.

In order to meet the requirements of sensing and controllong the metal cutting process automatically, a lot of effert has been made. Up to now the variability of thermal emf signal prevents it from being applied satisfactorily.

The diffuse phase transition in the polycrystal ferroelectrics Pb(Mgl/3Nb2/3)O3 and Pb(Nil/3Nb2/3)O, has been investigated under pressure up to 14kb. With increasing pressure p, diffuse factor u increase linearly, Curie-Weiss constant C and average Curie temperature T av decrease linearly. The phase transition becomes more diffused with increasing p. The ⟨E⟩ ∼ T curve can be explained in terms of the statistical model for diffuse phase transition. Using Martirena and Burfoot's experimental formula where T m is a temperature where e has the maximum in the ⟨e⟩ ∼ T curve, m and B are constants, the effect of pressure on the diffuse phase transition of the ferroelectrics Pb(Mg1/3Nb2/3)O, and Pb(Ni1/3Nb2/3)O3 can be analysed. Analogically, using the formula The pressure dependence of e at the various temperatures is shown.