Pavement snow and icing are worldwide problems, but effective countermeasures are just beginning to be developed in China. The two most common snow and ice removal methods are mechanical clearance and chemical melting...Pavement snow and icing are worldwide problems, but effective countermeasures are just beginning to be developed in China. The two most common snow and ice removal methods are mechanical clearance and chemical melting, and the advantages and disadvantages of each approach are discussed here, including environmental and structural damage caused by corrosive snow melting agents. New developments in chemical melting agents and mechanical equipment are discussed, and an overview of alternative thermal melting systems is presented, including the use of geothermy and non-geothermal heating systems utilizing solar energy, electricity, conductive pavement materials, and infrared/microwave applications. Strategic recommendations are made for continued enhancement of public safety in snow and ice conditions.展开更多
This paper concluded the vegetation restoration technique system in the arid-hot valleys and studied the anti-erosion function, environmental function and biological diversity effects of vegetation restoration on the ...This paper concluded the vegetation restoration technique system in the arid-hot valleys and studied the anti-erosion function, environmental function and biological diversity effects of vegetation restoration on the ecosystem in the arid-hot valleys. The results showed that the soil erodibility decreased significantly after the vegetation restoration. The climate environment of the small watershed had a great improvement after the vegetation restoration, of which the temperature decreased, the humidity increased, the harsh environment of dry and hot in this region changed. The studies of the ecosystem biodiversity were mainly on the analysis of the relations between biodiversity and ecological function of the artificial ecological forest pattern and the natural enclosed treatment mode on the severely of degraded land. It could conclude that the natural enclosed treatment mode is helpful to the biodiversity of the ecosystem and the improvement and stability of the ecosystem, and Leucaena artificial forest restoration pattern reduced the species diversity but optimized the ecological function. Therefore, as to the severely and extremely severely degraded ecosystem in the arid-hot valleys, Leucaena pattern of gully control and natural enclosed treatment mode are the relatively optimal choices.展开更多
The q-analogues of two-mode squeezed states are introduced by virtue of deformation quantization methods and the technique of integration within an ordered product （IWOP） of operators. Some new completeness relation...The q-analogues of two-mode squeezed states are introduced by virtue of deformation quantization methods and the technique of integration within an ordered product （IWOP） of operators. Some new completeness relations about these squeezed states composed of the bra and ket which are not mutually Hermitian conjugates are obtained. Furthermore, the antibunching effects of the two-mode squeezed vacuum state S＇s（τ） │00） are investigated. It is found that, in different ranges of the squeezed parameter τ, both modes of the state exhibit the antibunching effects and the two modes of the state are always nonclassical correlation.展开更多
Reproductive biotechnologies offer us greater possibilities to improve animal genetics. However, the success of these depends on different factors such as the proper selection of the donor female. For this reason, end...Reproductive biotechnologies offer us greater possibilities to improve animal genetics. However, the success of these depends on different factors such as the proper selection of the donor female. For this reason, endocrine markers have been used to evaluate the ovarian reserve, which allow a successful selection of donors. Recent research has shown, among other things, that concentrations greater than 0.130 ng/mL of anti-Mullerian hormone (also known as Muller-inhibiting substance, which is a member of the transforming growth factor beta superfamily of growth and differentiation factors) are related to donors of more than fifteen transferable embryos. Therefore, this review describes studies showing that the measurement of anti-Müllerian hormone concentrations, before superovulation programs, reduces the costs per embryo produced.展开更多
目的:探究双层软组织缝合封闭技术在单纯应用抗骨吸收药物引起的发生在下颌骨的中早期药物相关性颌骨骨坏死(medication-related osteonecrosis of the jaw,MRONJ)患者手术治疗中的临床应用效果。方法:选择2021年10月至2022年9月于北京...目的:探究双层软组织缝合封闭技术在单纯应用抗骨吸收药物引起的发生在下颌骨的中早期药物相关性颌骨骨坏死(medication-related osteonecrosis of the jaw,MRONJ)患者手术治疗中的临床应用效果。方法:选择2021年10月至2022年9月于北京大学口腔医院四病区经手术治疗的中早期下颌骨MRONJ患者的病历资料进行回顾性分析,收集患者术前基线临床资料,包括原发疾病、伴发疾病、用药方案(药物种类、用药时长)、MRONJ分期、临床症状、影像学表现等,所有患者在手术中行下颌骨边缘切除术去除坏死骨,运用双层软组织缝合封闭技术关闭伤口,术后定期复查随访,评价双层软组织缝合封闭技术的治疗效果及并发症,并对患者进行疼痛评分和功能状态评价。结果:研究共纳入13例患者(女12例,男1例),年龄(66.69±13.14)岁。原发疾病包括骨质疏松7例,肺癌2例,乳腺癌3例,前列腺癌1例;2例伴发糖尿病,2例伴发心血管疾病,1例伴发干燥综合征。9例患者静脉注射唑来膦酸,平均用药时间(37.7±20.0)个月,7例患者同时服用了来曲唑片等其他药物;3例患者应用地舒单抗注射液,平均用药时间(10.3±11.9)个月;5例患者服用阿仑膦酸钠片,平均用药时间(55.20±27.20)个月,2例患者不同程度地服用醋酸泼尼松片或阿卡波糖片。MRONJ 1期4例,2期9例。13例患者均采用双层软组织缝合封闭技术关闭伤口,术后平均随访11.9个月(9~17个月),13例患者皆治愈,无溢脓等并发症发生。患者术前Karnofsky功能状态评分量表(Karnofsky performance status,KPS)评分为(68.46±14.05)分,术后评分为(82.31±15.36)分,差异有统计学意义(P<0.05)。患者术前疼痛评估视觉模拟评分量表(visual analogue scale,VAS)评分为(5.77±0.73)分,术后评分为(0.38±0.51)分,差异有统计学意义(P<0.001)。结论:双层软组织缝合封闭技术在中早期单纯使用抗骨吸收类药物的下颌骨MRONJ患者中可以取得良好的临床治疗效果,可为用药情况更加复杂的MRONJ患者提供临床治疗思路。展开更多
Auto anti-collision technology is one of the main research subjects of automobiles’ safety technology. Aiming at the key technology of Auto anti-collision, measuring the distance from obstacles, based on the theory o...Auto anti-collision technology is one of the main research subjects of automobiles’ safety technology. Aiming at the key technology of Auto anti-collision, measuring the distance from obstacles, based on the theory of phase laser distance ranging, Laser Diode (LD) distance-measuring system for auto anti-collision has been developed to solve the problem of on-line measuring distance technology in middle to long distance utilizing the good characteristics of LD when modulating its optical intensity and adopting typical kinds of filter techniques in this paper. By theoretical analysis, adopting typical kinds of filter techniques can reduce the interference of strong light, so distance-measuring range can be 0.5–100 m in daytime or 1–200 m at night. And more, from theoretical analysis and experiment result, it can guarantee the high measuring resolution which can be less than 24.5 mm, utilizing the method of two Laser Diode optical intensity modulating wavelength and complimenting precise calibration and revision. The idea of LD distance-measuring technology is novel and feasible and this technology can be applied in Auto anti-collision. Key words laser diode - phase laser distance ranging - filter techniques - auto anti-collision CLC number TH 161 Foundation item: Supported by the National Natural Science Foundation of China (59675080, 59805006) and Wuhan Chenguang Foundation (20025001001)Biography: Zhang Xin-bao (1965-), male, Associate professor, research direction: precise mechanism and instrument.展开更多
Anti-plane electroelastic problems are studied by the Trefftz boundary element method （BEM） in this paper. The Trefftz BEM is based on a weighted residual formulation and indirect boundary approach. In particular th...Anti-plane electroelastic problems are studied by the Trefftz boundary element method （BEM） in this paper. The Trefftz BEM is based on a weighted residual formulation and indirect boundary approach. In particular the point-collocation and Galerkin techniques, in which the basic unknowns are the retained expansion coefficients in the system of complete equations, are considered. Furthermore, special Trefftz functions and auxiliary functions which satisfy exactly the specified boundary conditions along the slit boundaries are also used to derive a special purpose element with local defects. The path-independent integral is evaluated at the tip of a crack to determine the energy release rate for a mode Ⅲ fracture problem. In final, the accuracy and efficiency of the Trefftz boundary element method are illustrated by an example and the comparison is made with other methods.展开更多
The problem of an anti-plane Griffith crack moving along the interface of dissimilar piezoelectric materials is solved by using the integral transform technique. It is shown from the result that the intensity factors ...The problem of an anti-plane Griffith crack moving along the interface of dissimilar piezoelectric materials is solved by using the integral transform technique. It is shown from the result that the intensity factors of anti-plane stress and electric displacement around the crack tip are dependent on the speed of the Griffith crack as well as the material coefficients. When the two piezoelectric materials are identical, the present result will be reduced to the result far the problem of an anti-plane moving Griffith crack in homogeneous piezoelectric materials.展开更多
AIM To examine the efficacy of three extraction techniques: Soxhlet-extraction(SE), cold-maceration(CM) and microwave-assisted-extraction(MAE) using 80% methanol as solvent. METHODS The study was performed on each of ...AIM To examine the efficacy of three extraction techniques: Soxhlet-extraction(SE), cold-maceration(CM) and microwave-assisted-extraction(MAE) using 80% methanol as solvent. METHODS The study was performed on each of 50 g of Vernonia amygdalina(VA) and Occimum gratissimum(OG) leaves respectively. The percentage yield, duration of extraction, volume of solvent used, qualitative and quantitative phytoconstituents present was compared. The biological activities(hypoglycemic effect) were investigated using albino wistar rat model of diabetes mellitus(n = 36) with a combined dose(1:1) of the two plants leaf extracts(250 mg/kg b.w.) from the three methods. Theextracts were administered orally, once daily for 21 d.RESULTS In this report, the percentage VA extract yield from MAE was highest(20.9% ± 1.05%) within 39 min using 250 m L of solvent, when compared to the CM(14.35% ± 0.28%) within 4320 min using 900 m L of solvent and SE(15.75% ± 0.71%) within 265 min using 500 m L of solvent. The percentage differences in OG extract yield between: MAE vs SE was 41.05%; MAE vs CM was 46.81% and SE vs CM was 9.77%. The qualitative chemical analysis of the two plants showed no difference in the various phytoconstituents tested, but differs quantitatively in the amount of the individual phytoconstituents, as MAE had significantly high yield(P > 0.05) on phenolics, saponins and tannins. SE technique gave significantly high yield(P > 0.05) on alkaloid, while CM gave significant high yield on flavonoids. The extracts from CM exhibited a significantly(P > 0.05) better hypoglycemic activity within the first 14-d of treatment(43.3% ± 3.62%) when compared to MAE(36.5% ± 0.08%) and SE methods(33.3% ± 1.60%). However, the percentage hypoglycemic activity, 21 d post-treatment with 250 mg/kg b.w. extract from MAE was 72.6% ± 1.03% and it was more comparable to 10 mg/kg b.w. glibenclamide treated group(75.0% ± 0.73%), unlike the SE(69.5% ± 0.71%) and CM(69.1% ± 1.03%). CONCLUSION CM technique produces extract with better hypoglycemic activity, whereas; MAE is a better option for high yield of phytoconstituents using less solvent within a short time.展开更多
基金supported by the National Natural Science Fund of China(No.41121061)the National Key Basic Research and Development Program(No.2012CB026102)the Fund of the "Hundred People Plan" of CAS(to WenBing Yu)
文摘Pavement snow and icing are worldwide problems, but effective countermeasures are just beginning to be developed in China. The two most common snow and ice removal methods are mechanical clearance and chemical melting, and the advantages and disadvantages of each approach are discussed here, including environmental and structural damage caused by corrosive snow melting agents. New developments in chemical melting agents and mechanical equipment are discussed, and an overview of alternative thermal melting systems is presented, including the use of geothermy and non-geothermal heating systems utilizing solar energy, electricity, conductive pavement materials, and infrared/microwave applications. Strategic recommendations are made for continued enhancement of public safety in snow and ice conditions.
基金the National Science and Technology Supporting Program in the Eleventh Five-Year Plan of China(2006BAC01A11)the Natural Science Founda-tion of Yunnan Province (2006D0092M)
文摘This paper concluded the vegetation restoration technique system in the arid-hot valleys and studied the anti-erosion function, environmental function and biological diversity effects of vegetation restoration on the ecosystem in the arid-hot valleys. The results showed that the soil erodibility decreased significantly after the vegetation restoration. The climate environment of the small watershed had a great improvement after the vegetation restoration, of which the temperature decreased, the humidity increased, the harsh environment of dry and hot in this region changed. The studies of the ecosystem biodiversity were mainly on the analysis of the relations between biodiversity and ecological function of the artificial ecological forest pattern and the natural enclosed treatment mode on the severely of degraded land. It could conclude that the natural enclosed treatment mode is helpful to the biodiversity of the ecosystem and the improvement and stability of the ecosystem, and Leucaena artificial forest restoration pattern reduced the species diversity but optimized the ecological function. Therefore, as to the severely and extremely severely degraded ecosystem in the arid-hot valleys, Leucaena pattern of gully control and natural enclosed treatment mode are the relatively optimal choices.
基金Project supported by the National Natural Science Foundation of China (Grant No 10574060)the Natural Science Foundation of Liaocheng University of China (Grant No X071049)
文摘The q-analogues of two-mode squeezed states are introduced by virtue of deformation quantization methods and the technique of integration within an ordered product （IWOP） of operators. Some new completeness relations about these squeezed states composed of the bra and ket which are not mutually Hermitian conjugates are obtained. Furthermore, the antibunching effects of the two-mode squeezed vacuum state S＇s（τ） │00） are investigated. It is found that, in different ranges of the squeezed parameter τ, both modes of the state exhibit the antibunching effects and the two modes of the state are always nonclassical correlation.
文摘Reproductive biotechnologies offer us greater possibilities to improve animal genetics. However, the success of these depends on different factors such as the proper selection of the donor female. For this reason, endocrine markers have been used to evaluate the ovarian reserve, which allow a successful selection of donors. Recent research has shown, among other things, that concentrations greater than 0.130 ng/mL of anti-Mullerian hormone (also known as Muller-inhibiting substance, which is a member of the transforming growth factor beta superfamily of growth and differentiation factors) are related to donors of more than fifteen transferable embryos. Therefore, this review describes studies showing that the measurement of anti-Müllerian hormone concentrations, before superovulation programs, reduces the costs per embryo produced.
文摘目的:探究双层软组织缝合封闭技术在单纯应用抗骨吸收药物引起的发生在下颌骨的中早期药物相关性颌骨骨坏死(medication-related osteonecrosis of the jaw,MRONJ)患者手术治疗中的临床应用效果。方法:选择2021年10月至2022年9月于北京大学口腔医院四病区经手术治疗的中早期下颌骨MRONJ患者的病历资料进行回顾性分析,收集患者术前基线临床资料,包括原发疾病、伴发疾病、用药方案(药物种类、用药时长)、MRONJ分期、临床症状、影像学表现等,所有患者在手术中行下颌骨边缘切除术去除坏死骨,运用双层软组织缝合封闭技术关闭伤口,术后定期复查随访,评价双层软组织缝合封闭技术的治疗效果及并发症,并对患者进行疼痛评分和功能状态评价。结果:研究共纳入13例患者(女12例,男1例),年龄(66.69±13.14)岁。原发疾病包括骨质疏松7例,肺癌2例,乳腺癌3例,前列腺癌1例;2例伴发糖尿病,2例伴发心血管疾病,1例伴发干燥综合征。9例患者静脉注射唑来膦酸,平均用药时间(37.7±20.0)个月,7例患者同时服用了来曲唑片等其他药物;3例患者应用地舒单抗注射液,平均用药时间(10.3±11.9)个月;5例患者服用阿仑膦酸钠片,平均用药时间(55.20±27.20)个月,2例患者不同程度地服用醋酸泼尼松片或阿卡波糖片。MRONJ 1期4例,2期9例。13例患者均采用双层软组织缝合封闭技术关闭伤口,术后平均随访11.9个月(9~17个月),13例患者皆治愈,无溢脓等并发症发生。患者术前Karnofsky功能状态评分量表(Karnofsky performance status,KPS)评分为(68.46±14.05)分,术后评分为(82.31±15.36)分,差异有统计学意义(P<0.05)。患者术前疼痛评估视觉模拟评分量表(visual analogue scale,VAS)评分为(5.77±0.73)分,术后评分为(0.38±0.51)分,差异有统计学意义(P<0.001)。结论:双层软组织缝合封闭技术在中早期单纯使用抗骨吸收类药物的下颌骨MRONJ患者中可以取得良好的临床治疗效果,可为用药情况更加复杂的MRONJ患者提供临床治疗思路。
文摘Auto anti-collision technology is one of the main research subjects of automobiles’ safety technology. Aiming at the key technology of Auto anti-collision, measuring the distance from obstacles, based on the theory of phase laser distance ranging, Laser Diode (LD) distance-measuring system for auto anti-collision has been developed to solve the problem of on-line measuring distance technology in middle to long distance utilizing the good characteristics of LD when modulating its optical intensity and adopting typical kinds of filter techniques in this paper. By theoretical analysis, adopting typical kinds of filter techniques can reduce the interference of strong light, so distance-measuring range can be 0.5–100 m in daytime or 1–200 m at night. And more, from theoretical analysis and experiment result, it can guarantee the high measuring resolution which can be less than 24.5 mm, utilizing the method of two Laser Diode optical intensity modulating wavelength and complimenting precise calibration and revision. The idea of LD distance-measuring technology is novel and feasible and this technology can be applied in Auto anti-collision. Key words laser diode - phase laser distance ranging - filter techniques - auto anti-collision CLC number TH 161 Foundation item: Supported by the National Natural Science Foundation of China (59675080, 59805006) and Wuhan Chenguang Foundation (20025001001)Biography: Zhang Xin-bao (1965-), male, Associate professor, research direction: precise mechanism and instrument.
基金Project supported by the National Natural Science Foundation of China (No. 10472086).
文摘Anti-plane electroelastic problems are studied by the Trefftz boundary element method （BEM） in this paper. The Trefftz BEM is based on a weighted residual formulation and indirect boundary approach. In particular the point-collocation and Galerkin techniques, in which the basic unknowns are the retained expansion coefficients in the system of complete equations, are considered. Furthermore, special Trefftz functions and auxiliary functions which satisfy exactly the specified boundary conditions along the slit boundaries are also used to derive a special purpose element with local defects. The path-independent integral is evaluated at the tip of a crack to determine the energy release rate for a mode Ⅲ fracture problem. In final, the accuracy and efficiency of the Trefftz boundary element method are illustrated by an example and the comparison is made with other methods.
基金the National Natural Science Foundationthe National Post-doctoral Science Foundation of China
文摘The problem of an anti-plane Griffith crack moving along the interface of dissimilar piezoelectric materials is solved by using the integral transform technique. It is shown from the result that the intensity factors of anti-plane stress and electric displacement around the crack tip are dependent on the speed of the Griffith crack as well as the material coefficients. When the two piezoelectric materials are identical, the present result will be reduced to the result far the problem of an anti-plane moving Griffith crack in homogeneous piezoelectric materials.
文摘AIM To examine the efficacy of three extraction techniques: Soxhlet-extraction(SE), cold-maceration(CM) and microwave-assisted-extraction(MAE) using 80% methanol as solvent. METHODS The study was performed on each of 50 g of Vernonia amygdalina(VA) and Occimum gratissimum(OG) leaves respectively. The percentage yield, duration of extraction, volume of solvent used, qualitative and quantitative phytoconstituents present was compared. The biological activities(hypoglycemic effect) were investigated using albino wistar rat model of diabetes mellitus(n = 36) with a combined dose(1:1) of the two plants leaf extracts(250 mg/kg b.w.) from the three methods. Theextracts were administered orally, once daily for 21 d.RESULTS In this report, the percentage VA extract yield from MAE was highest(20.9% ± 1.05%) within 39 min using 250 m L of solvent, when compared to the CM(14.35% ± 0.28%) within 4320 min using 900 m L of solvent and SE(15.75% ± 0.71%) within 265 min using 500 m L of solvent. The percentage differences in OG extract yield between: MAE vs SE was 41.05%; MAE vs CM was 46.81% and SE vs CM was 9.77%. The qualitative chemical analysis of the two plants showed no difference in the various phytoconstituents tested, but differs quantitatively in the amount of the individual phytoconstituents, as MAE had significantly high yield(P > 0.05) on phenolics, saponins and tannins. SE technique gave significantly high yield(P > 0.05) on alkaloid, while CM gave significant high yield on flavonoids. The extracts from CM exhibited a significantly(P > 0.05) better hypoglycemic activity within the first 14-d of treatment(43.3% ± 3.62%) when compared to MAE(36.5% ± 0.08%) and SE methods(33.3% ± 1.60%). However, the percentage hypoglycemic activity, 21 d post-treatment with 250 mg/kg b.w. extract from MAE was 72.6% ± 1.03% and it was more comparable to 10 mg/kg b.w. glibenclamide treated group(75.0% ± 0.73%), unlike the SE(69.5% ± 0.71%) and CM(69.1% ± 1.03%). CONCLUSION CM technique produces extract with better hypoglycemic activity, whereas; MAE is a better option for high yield of phytoconstituents using less solvent within a short time.
