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This study aimed to investigate the effect of dexamethasone (DEX) on chemotaxis and phagocytic activity of neutrophils for spermatozoa and semen quality of preserved boar semen. The different concentrations of dexamethasone were added to boar semen dilutions to detect its effects on the chemotaxis of neutrophils and phagocytosis of neutrophils and sperm motility sperm malformation rate, plasma membrane integrity, mitochondrial activity, and spermatozoa motility parameters. The study results showed that the experimental groups of DEX significantly inhibited the phagocytosis and chemotaxis of PMNs for spermatozoa. With the increased concentration of DEX, there was an inhibition effect on PMNs activity. In addition, under 17 °C storage conditions, the addition of DEX 1 × 10

In order to fabricate green composites without the emission of toxic volatile compounds, wood fiber (WF) biocomposites reinforced with polylactic acid (PLA) were prepared utilizing the traditional hot-press manufacturing process. The effect of adding ammonium lignosulfonate (AL) on the mechanical and dimensional properties of the biocomposites was investigated. When the mass ratio of WF to PLA is 7:3 and the AL mass percentage is in the range from 1 to 20 wt%, the modulus of rupture of the WF/PLA/AL composites ranged from 21.95 to 36.96 MPa, the modulus of elasticity ranged from 3078.6 to 4157.8 MPa and the internal bonding strength ranged from 0.69 to 1.71 MPa, which showed a 4.0–75.1% increase in modulus of rupture, a 3.5–39.8% increase in modulus of elasticity and a 21.5–201.2% increase in internal bonding strength compared to the corresponding WF/PLA composites due to the reinforcing effect of AL. However, AL negatively affected the dimensional properties of the biocomposites. The thickness swell of the WF/PLA/AL composites ranged from 18.7 to 43.5% and the water absorption ranged from 47.1 to 78.9%. The thickness swell, water absorption and contact angle of the WF/PLA/AL composites increased with the AL mass percentage due to its high hydrophilicity, resulting in a 1.1–132.6% and a 3.4–67.4% increase in thickness swell and water absorption, respectively. AL had a positive effect on the crystallinity of the biocomposites due to its good surface activity as long as the AL mass percentage was below 20 wt%. The fractured surface of the WF/PL/AL composites clearly showed that a strong bond (mechanical interlocking and/or chemical bonding) exists at the interface resulting in an effective stress transfer.

This experimental study investigates the heat transfer properties over developing and developed flow regimes, the pressure drop coefficients and the thermal performance factors (TPF) of tubular flows with the continuous and spiky twist tapes enhanced by perforated, jagged and notched winglets. The axial distributions of Nusselt number (Nu) and the mean Fanning friction factors (f) of the tubular flows at Reynolds numbers (Re) ranging from 500 to 40000 are comparatively examined for five different types of twisted tapes with three twist ratios (y) of 1.875, 2.186 and 2.815 for each type of twisted tapes. Through this comparative study, the favorable types of twisted tapes which generate the higher degrees of HTE impacts over the developing and developed flow regimes are respectively identified. These newly devised twist tapes enrich the varieties of passive heat transfer enhancement (HTE) devices, especially for retrofit applications. A set of selective Nu and f results illustrates the thermal characteristics of the enhanced tubular flows by these twisted tapes. The HTE and TPF properties for all the present types of twisted tapes are subsequently compared with those reported for other types of twisted tapes in the literature. Among these comparative groups, the present V-notched spiky twisted tape generally offers the highest HTE impacts with favorable TPF performances. Empirical correlations that evaluate the averaged Nu over the developing and developed flow regimes; as well as and tube-wise averaged f for the enhanced tubular flows fitted with all the present types of twisted tapes are generated.

The paper which based on the idea of “low carbon economy” scanned the wood carbon storage function and analyzed the wood carbon storage from the present research situation of home and abroad. And it put forward the research content and specific research methods of the wood carbon storage. Finally it summarized the expected achievement and development trend of studying the wood carbon storage under the construction of low carbon economy. The research will have the practical directive function about realizing the energy saving and emission reduction of carbon dioxide, transforming the mode of economic development and improving the wood’s carbon storage.

To pack a certain quality ratio ammonium lignosulfonate / urea as a filler into the natural wood fiber, Using flat pressure process fiberboard materials, Optimize the hot pressing technique that the filler is 20% (The quality ratio of lignosulfonate/ urea is 5: 3), slab moisture content is 13%, hot-pressing temperature is 190°C; hot-pressing time is 7 minutes, hot-pressing pressure is 2MPa and 1% paraffin emulsion. Verifying test results show that mechanical performance is stable and reliable process. Analyze the reactivity of fiberboard packing, fiber gathered, the microstructure of interface properties with the application of FTIR, XRD and ESEM and other modern instrument analysis technology.

In order to explore the factors of fraxinus mandshurica veneer dye-uptake, the discourse made use of reactive dyes. The result showed that significant effects of fraxinus mandshurica veneer dye uptake are reactive dye concentration, dyeing temperature, dyeing time and sodium chloride concentration. The artificial dyeing technology of fraxinus mandshurica was defined finally. Using reactive dyes, reactive red X-3B 10 g/L, temperature 95 °C, the dyeing time 240 min, sodium chloride 30 g/L. The study provided a theory gist and a practical guidance role for imitation precious wood.

In our research, a commercial poly (lactic acid) (PLA) film was used in combination with wood fiber matrix to generate biodegradable composites by a film stacking technique and hot-press. The results showed the flexural properties and water resistance increased with the increasing of PLA addition. Silane-treated wood fiber composites significantly improved the flexural properties compared to untreated composites. In experiment range, the physical and mechanical properties of composites were better in higher hot-press temperature. The optimal parameters are determined by PLA addition 20%, silane addition 3%, the hot-press temperature 190°C, the hot-press time 10min.Under these parameters, the flexural properties of composites exceeded the requirement of the outdoor boards’ standard, but the water resistance was a little low.

Dyeing experiment was conducted to explore the effects of dyeing concentration, Penetrant concentration, ash concentration, salt concentration, dyeing temperature and dyeing time, Fixing time, liquor ratio on surface coloration of Pinus sylvest var. mongolica as test material and reactive brilliant red X-3B as reagents. Color difference was measured by amulti-lightsource spectrophotometer, and results showed that dye concentration for the effects of color difference was monotonous relationship, and the other the impact of changed in both convex and concave, and finally to determined the optimal color for the dyeing process: dyeing concentration1%, Penetrant concentration0.1%, ash concentration, 2.5% salt concentration1.5%, dyeing temperature85°C and dyeing time60min, Fixing time40min, liquor ratio17:1.

This paper takes plantation pinus sylvestnis var. mongolica litv. as study object, determines main anatomical factors influencing wood dyeing effects by measuring the related indexes of wood anatomical structure and dyeing effects, making a multiple regression analysis of them and analyzing the correlation variation law between wood anatomical structure and dyeing effects. The results show that there is a high correlation between pinus sylvestnis var. mongolica litv. dyeing effects and wood anatomical factors and the multiple correlation coefficients between anatomical factors and various dyeing effect indexes are between 0.573 and 0.786. The main anatomical factors influencing pinus sylvestnis var.mongolica litv.dyeing effects are tracheid proportion, wood ray proportion, resin canal proportion and late wood tracheid length, etc.

Standing wave tube was used to test the sound absorption abilities and analyze the influence factors of perforated medium density fiberboard (MDF). The test results show that bore diameter, perforated rate and different depth of space from the structure are the key factors influencing the absorption performance of wooden perforated panels, but decorative facing and bore shape have a little contribution to absorption abilities. Research finds that absorption peak will move towards high-frequency with decreasing the bore diameter so as to increase absorption effect in high-frequency, and excellent high-frequency absorption performance can be achieved by increasing perforated rate. On the other hand, larger depth of space from the structure will raise the absorption abilities in low-frequency of the panel.

The tests on physical and mechanical properties of fiberboards made of wood fiber with ammonium lignosulphonate/urea as filling material are performed according to requirement of EU standards EN 622-2-2004 "Fibreboard-Specifications Part 2: Requirements for hardboard" reveal the reaction mechanism of formaldehyde-free fiberboards with ammonium lignosulfonate /urea as filling material through analysis of characteristics of chemical reactions on ammonium lignosulfonate and urea by FTIR and the chemical reaction analysis of C atom by ESCA. The results show that physical and mechanical properties of fiberboards with ammonium lignosulphonate/urea as filling material have reached the requirement of EU standards EN 622-2-2004, the forming of furan resin, the results of reaction between urea and furfural substances is main reason for the better physical and mechanical properties of lignin-based formaldehyde-free fiberboard.

The changes of the surface colors and chemical constituents of Mongolian Scotch pine treated by UV light were investigated by spectrophotometer and FTIR followed by acid pretreatment. The results show that the changes of the surface colors are related to carbonyl, aromatic nucleus, arone, Ar-OH, paraquinones, ortho quinine and so on in the course of UV irradiation. Acid promotes photocycloaddition and plays a hyperchromic effect.

Trees are complicated and important organisms in forest ecosystem. They are both carbon stocks and carbon source. In order to give full play to the role of wood carbon sequestration, this paper discussed the relationship of wood structural features and wood carbon sequestration at micro-level. It shows that wood carbon sequestration can be synthetically reflected by vessel, tracheid/xylon, wood rays, intercellular canal, xylem parenchyma and so on. The rate of cell wall and wood carbon sequestration is the relationship of direct proportional function. Micro-structural characteristics of wood can reflect wood carbon sequestration of forest ecosystems, as well as have a practical guide to enhance carbon storage of wood.

BACKGROUND AND PURPOSE Current criteria for middle cerebral artery (MCA) stenosis by transcranial Doppler were mainly based on the flow velocity acceleration, ignoring other useful parameters. We tested the accuracy of new criteria using magnetic resonance angiography (MRA) as the confirmative method. METHODS A compositive score for each MCA was calculated according to following parameters: Velocity Scale (score 0-6 for peak systolic velocity

To study the plasma homocysteine (Hcy) distributive characteristics in different sex and age groups of the community residents in Guangdong, and to analyze its associated factors as well as its effects on cerebral artery stenosis.In this study, we presented data concerning 2500 residents who had undergone a systematic health checkup,including clinical and biologic examinations. Plasma was saved from 1020 residents who were asymptomatic but having TCD examination. Hcy concentration was measured by fluorescence ration biochemical assay kit.The average plasma Hcy levels of males (15.0 micromol/L+/-5.8 micromol/L) were significantly higher than those of females (12.4 micromol/L-I 3.9 micromol/L, P0.05). Hcy level increased parallel with age. The prevalence rate of hyperhomocysteinemia in males (47.2%) was higher than in females (23.2%). Hcy levels in MCA stenosis group (18.3 micromol/L+ 5.3 micromol/L) were significantly higher than that in control group (12.9 micromol/L+/- 4.6 micromol/L, P0.05). Based on logistic regression analysis, Hcy was only associated with sex and age, but not with blood lipids etc.Hcy levels were different in sex and age groups which emerged as independent predictors of hyperhomocysteinemia but had no association with blood lipids in the community residents, suggesting that hyperhomocysteinemia might worsen cerebral artery stenosis.

Backgrounds: Intracranial atherosclerosis is the commonest vascular lesion for ischemic stroke in Asians. Most research on risk factors for middle cerebral artery (MCA) stenosis has been conducted in symptomatic patients with ischemic stroke or transient ischemic attack. The present study aimed to investigate risk factors for MCA stenosis in an asymptomatic population in Rongqi County in Southern China. Methods: We assessed 1,068 asymptomatic subjects over 50 years of age by transcranial Doppler. Medical history documentation and investigation of biochemical markers were performed for each subject. Multivariant, unconditioned, logistic regression analyses were employed to assess the risk factors associated with MCA stenosis. Results: MCA stenosis was found in 63 subjects (5.9%). Male gender, advancing age, hypertension, diabetes and systolic blood pressure were significant risk factors for MCA stenosis (p < 0.001). Based on logistic regression analyses, 4 factors emerged as independent risk factors (p < 0.001) of MCA stenosis: male gender [95% confidence interval (CI) = 1.49–4.66, OR = 2.63], age (95% CI = 1.01–1.06, OR = 1.04), hypertension (95% CI = 4.57–18.35, OR = 9.16) and diabetes mellitus (95% CI = 3.09–11.29, OR = 5.9). Conclusion: MCA stenosis is relatively common among asymptomatic Chinese subjects. Male gender, advanced age, hypertension and diabetes mellitus are risk factors for MCA stenosis.

Hyperhomocysteinemia (HHcy) is considered to be an independent risk factor for atherosclerosis. We aimed to determine the relation between Hcy and cerebral artery stenosis in a large Chinese population. We present data concerning 2,500 residents. Plasma was saved from 1,020 residents who were asymptomatic. Hcy concentration was measured by fluorescence ration biochemical assay kit, and middle cerebral artery (MCA) was assessed by Transcranial Doppler in these subjects. Fifty-six residents with MCA stenosis were included in this study. The remained 964 residents without stenosis were control. Analysis of the data revealed that the plasma concentration of Hcy (18.33 ± 5.34 µmol/L), age (63.9 ± 12.9) and systolic pressure (142.6 ± 22.6 mmHg) in the stenotic group were increased (p

To study the rates of receiving doppler signal, flow velocity of cerebral artery and the relationship between flow velocity,age and gender in normal adults in China.A total of 1500 normal residents at the community level in Guangdong province were examined, using transcranial doppler. Data was gathered and analyzed.With the increase of age, the rate of receiving signal in cerebral artery gradually decreased. Difference between males and females was noticed. Mean velocity of cerebral artery decreased in both genders but the velocity was faster in females than in males and the pulsate index increased without difference.The rates of receiving signal and the flow velocity of cerebral artery were related to age and gender and the findings from this study offered criterion for clinical transcranial doppler.