Coupled DEM-FDM analyses of the effects of falling rock’s shape and impact angle on response of granular cushion and rock shed

Rock shed is an effective protection measure against rockfall.To investigate the influences of falling rock’s shape and impact angle on the impact effect of the cushioned rock shed,a modeling approach for a rock shed with a cushion layer using PFC-FLAC.The granular cushion is modeled as an aggregate of discrete non-cohesion particles,while the concrete plate and the beam are modeled as zones.The falling rock with different sphericities and impact angles is modeled as a rigid assembly.The numerical model is validated by comparing the simulation results with experimental and numerical results from previous literature.This model is applied to analyze the effects of rock shape and impact angle on the dynamic interaction effects between falling rock and cushioned rock shed,including the impact force,transmitted bottom force,penetration depth,and plate deflection.The numerical results show that the variation in the falling rock’s shape has different effects on the falling rock with different impact angles.These findings could support rock shed design by revealing the limitations of the assumptions in the past research,which may result in unsafe rock sheds for some rockfall cases.

A Procedure for Trisecting an Acute Angle (Method 2)

This paper presents an alternate graphical procedure (Method 2), to that presented in earlier publications entitled, “A Procedure for Trisecting an Acute Angle” and “A Key to Solving the Angle Trisection Problem”. The procedure, when applied to the 30˚ and 60˚ angles that have been “proven” to be nottrisectable and the 45˚ benchmark angle that is known to be trisectable, in each case produced a construction having an identical angular relationship with Archimedes’ Construction, as in Section 2 on THEORY of this paper, where the required trisection angle was found to be one-third of its respective angle (i.e. DE’MA = 1/3 DE’CG). For example, the trisection angle for the 30˚, 45˚ and 60˚ angles were 10.00000˚, 15.00000˚, and 20.00000˚, respectively, and Section 5 on PROOF in this paper. Therefore, based on this identical angular relationship and the numerical results (i.e. to five decimal places), which represent the highest degree of accuracy and precision attainable by The Geometer’s Sketch Pad software, one can only conclude that not only the geometric requirements for arriving at an exact trisection of the 30˚ and 60˚ angle (which have been “proven” to be not-trisectable) have been met, but also, the construction is valid for any arbitrary acute angle, despite theoretical proofs to the contrary by Wantzel, Dudley, and others.

A Simplified Graphical Procedure for Constructing a 10˚or 20˚Angle

This paper presents a simplified graphical procedure for constructing, using an unmarked straightedge and a compass only, a 10˚ to 20˚ angle, which is in other words, trisecting a 30˚ or 60˚ angle. The procedure, when applied to the 30˚ and 60˚ angles that have been “proven” to be not trisectable, produced a construction having the identical angular relationship with Archimedes’ Construction, in which the required trisection angles were found to be 10.00000˚ and 20.00000˚ respectively (i.e. exactly one-third of the given angle or ∠E’MA = 1/3∠E’CG). Based on this identical angular relationship as well as the numerical results obtained, one can only conclude that the geometric requirements for arriving at an exact trisection of the 30˚ or 60˚ angle, and therefore the construction of a 10˚ or 20˚ angle, have been met, notwithstanding the theoretical proofs of Wantzel, Dudley, and others. Thus, the solution to the age-old trisection problem, with respect to these two angles, has been accomplished.

A Key to Solving the Angle Trisection Problem

This paper describes the methodology (or approach) that was key to the solution of the angle trisection problem published earlier in article entitled, “A Procedure For Trisecting An Acute Angle.” It was an approach that required first, designing a working model of a trisector mechanism, second, studying the motion of key elements of the mechanism and third, applying the fundamental principles of kinematics to arrive at the desired results. In presenting these results, since there was no requirement to provide a detailed analysis of the final construction, this information was not included. However, now that the publication is out, it is considered appropriate as well as instructive to explain more fully the mechanism analysis of the trisector in graphical detail, as covered in Section 3 of this paper, that formed the basis of the long sought solution to the age-old Angle Trisection Problem.

骨性Angle′s Ⅲ类错患者正畸手术前后下颌角矢量点位置的变化及意义

目的观察骨性Angle′sⅢ类错患者下颌角矢量点(Gov点)位置变化,并探讨其临床意义。方法取天津地区健康人29例为对照组,接受正手术治疗的骨性Angle′sⅢ类错畸形患者15例为观察组。均拍摄头颅侧位X线片,测量Gov点的座标。结果观察组术前、术后及对照组Gov点横坐标分别为(-4.54±0.51)、(-5.10±0.69)、(-5.02±0.35)cm,纵坐标分别为(-7.76±0.40)、(-7.65±0.57)、(-7.50±0.43)cm,观察组术前Gov点横、纵坐标与术后及对照组比较P均<0.05,观察组术后与对照组Gov点横、纵坐标比较P均>0.05。对照组下颌神经孔与Gov点间距为(1.35±0.16)cm,观察组术前为(1.27±0.19)cm,两组相比P>0.05。结论骨性Angle′sⅢ类错患者Gov点位置向前下移位,正手术后得以纠正。Gov点位置可能与下颌功能状态存在内在联系,可以作为正手术术前制定手术计划及术后评估矫治效果的指标。

Modified viscocanalostomy in the Chinese population with open angle glaucoma: a 10-year follow-up results

AIM: To study the long-term efficacy and safety of modified viscocanalostomy in Chinese people with open angle glaucoma(OAG).METHODS: This retrospective study included a total of 100 eyes from 100 Chinese patients with medically uncontrolled OAG. All the patients underwent modified viscocanalostomy with injection of viscoelastic material in the surgically created ostia of Schlemm's canal(SC). The modifications included peeling of the inner wall of SC and the juxtacanalicular meshwork, use of mitomycin C, and loosely suturing the superficial scleral flap. Intraocular pressure(IOP), visual acuity, number of medications, laser goniopuncture data and complications were recorded. The definition of complete(qualified) success was an IOP equal to or lower than 21, 18, 16 mm Hg without(with or without) anti-glaucoma medications. RESULTS: The mean IOP was 33.5±9.9 mm Hg before surgery, 15.2±3.6 mm Hg(mean IOP reduction of 51%) at 5 y after surgery, and 15.6±2.8 mm Hg(mean IOP reduction of 49.9%) at 10 y after surgery(P<0.001). The number of anti-glaucoma medications dropped from 2.39±0.5 preoperatively to 0.47±0.8 at 5 y and 0.67±0.8 at 10 y postoperatively(P<0.001). The follow-up period was 104.5±37.0 mo. The qualified success rate for an IOP of 21, 18 or 16 mm Hg or less was 84% [95% confidence interval(CI): 0.80-0.88], 73%(95%CI: 0.68-0.78), and 59%(95%CI: 0.52-0.66) after 5 y, and 80%(95%CI: 0.76-0.84), 69%(95%CI: 0.64-0.74), 51%(95%CI: 0.44-0.58) after 10 y, respectively. There was a relationship between age, preoperative IOP and success rate(P<0.01, P<0.05). A total of 31 eyes(31.3%)in 31 patients underwent laser goniopuncture, decreasing the IOP from 22.9±4.3 mm Hg to 16.3±2.5 mm Hg(P<0.01). Neither blebitis nor endophthalmitis occurred.CONCLUSION: Modified viscocanalostomy could be performed to lower IOP, decrease multiple anti-glaucoma drops use as well. It's a safe procedure with less complications over 10 y in Chinese individuals with OAG.

Elevated urine formaldehyde in elderly patients with primary open angle glaucoma

AIM：To investigate the risk factor of primary open angle glaucoma（POAG）,which is the leading cause of irreversible blindness worldwide.An abnormally high level of endogenous formaldehyde（FA） has recently been found correlated with cell death and neurodegenerative disease,raising the possibility of a putative correlation of abnormal endogenous FA with POAG.· METHODS：Thirty-four elderly patients with POAG and sixteen healthy controls were enrolled.Glaucomatous visual defects were present at both the functional（visual field） and structural[retinal nerve fiber layer（RNFL）thickness]levels.Morning urine samples were obtained and were analyzed by high-performance liquid chromatography（HPLC） to detect the endogenous FA level in a double blind manner.· RESULTS：Patients with POAG（P 〈0.05） had significantly higher urine FA levels.The urine FA level of patients with severe visual field defects[mean deviation（MD）≥12 dB]was significantly（P〈0.001） greater than that of patients with mild to moderate defects（MD〈12 dB）.By optical coherence tomography（OCT）,the superior and inferior RNFL thickness of POAG group was significantly（P〈0.001） thinner than in controls.Furthermore,the superior and inferior thinning of the RNFL was correlated with the elevation of urine FA concentration.CONCLUSION：Endogenous FA level is positively correlated with the neuronal defects of POAG.

Fecal-associated microbiome differences between phlegm-dampness constitution and balanced constitution

Objective: This study aimed to explore the structural and functional characteristics of the fecalassociated microbiome(FAM) between the phlegm-dampness constitution(PDC) and balanced constitution(BC), and to screen the related specific operational taxonomic unit(OTU) biomarkers.Methods: This was a cross-sectional study. After strictly identifying the constitution of subjects, their clinical index was recorded and counted. Fecal samples were collected for 16S rDNA sequencing. Alpha diversity, beta diversity, and the relative abundance of dominant bacterial taxa were used to describe the FAM structure, and the Wilcoxon rank-sum test, Metagenome Seq, and linear discriminant analysis effect size(LEf Se) were used to screen specific bacterial taxa. Specific OTUs were screened to construct receiver operating characteristic(ROC) curves.Results: Thirty-two subjects were enrolled, including 22 subjects with BC and 10 subjects with PDC.There were significant differences in cold preference, levels of aspartate transaminase, β2-microglobulin,and creatine kinase MB, and alpha diversity indices(Shannon and Shannoneven) between the two groups. In principal coordinate analysis by abund-jaccard distance measure and partial least squares discriminant analysis, bacterial communities clustered separately between the two groups. Furthermore,based on Metagenome Seq, LEf Se, and the Wilcoxon rank-sum test, a total of 43, 18, and 130 OTUs were differentially distributed between BC group and PDC group, respectively, and OTU200, OTU133, and OTU353 were screened when P≤.01. The area under the ROC curve constructed from the 3 selected OTUs was 0.93.Conclusion: The FAM structure and related functional characteristics of the PDC group differed from those of the BC group. In particular, OTU200, OTU133, and OTU353 can be used as unique markers of PDC to assist clinical diagnosis.

S弯收扩喷管过膨胀状态下流动分离特性研究

为了研究S弯收扩喷管过膨胀状态下的流动分离特性,数值模拟了不同落压比(NPR)下S弯收扩喷管内的流动特征。结果表明:在落压比为2.0时,喷管内发生非对称分离,出现非对称的双“λ”激波结构,喷流整体向上偏转,上侧出现限制性流动分离RSS,下侧出现自由性流动分离FSS,并产生三维分离涡,喷流出现明显的三维效应。随着落压比从高度过膨胀状态下开始增加,喷管下侧保持FSS不变,喷管上侧RSS逐渐向后移动,直至与外界大气相连,转变为FSS,之后随着落压比增加,上下侧分离结构逐渐对称。推力矢量角随着落压比的增加先增加,后在极小的落压比变化范围内快速降低,直至变为0°,之后保持0°不变。

Screening influencing factors of blood stasis constitution in traditional Chinese medicine

Objective To study the influencing factors of blood stasis constitution and provide a basis for treating blood stasis-related diseases by traditional Chinese medicine(TCM) constitution identification.Methods Data were collected using the self-developed TCM constitution identification platform based on B/S model by the project team. The obtained data were divided into blood stasis constitution and normal constitution groups. The differences of the categorical type influencing factors(gender, birth mode, feeding mode within four months of birth, family history, marital status, eating habits, sleeping habits, exercise habits, emotional state, stress situation, and living environment) and the quantitative type influencing factors(sleep time, age,and mother’s age at birth) on the constitution of the two groups were analyzed. In the singlefactor analysis, the Pearson’s chi-square test was selected for the categorical variable, and the independent sample t test and Mann-Whitney U nonparametric test were selected for the quantitative variables according to whether they conformed to the positive-terrestrial distribution;the binary logistic stepwise regression method was selected for the multi-factor analysis.Results The data of 318 cases were collected from the TCM composition identification platform, and 159 cases of blood stasis constitution were used as the experimental group and 159 cases of normal constitution were used as the control group. The Pearson’s chi-square test yielded significant differences(P < 0.05) in the effects of gender, pressure situation, family history, living environment, emotional state, exercise habits, and dietary habits on blood stasis constitution. The independent samples t test yielded differences in sleep duration between the blood stasis constitution and normal constitution populations(P < 0.05), which meant sleep duration of the blood stasis constitution population was less than that of the normal constitution population. The Mann-Whitney U nonparametric test results accepted the original hypothesis that there was no difference in the distribution of age and mother’s age at birth across constitution types(P > 0.05). Binary logistic regression analysis showed that gender, family history, marital status, living environment, exercise habits, and emotional state were risk factors for blood stasis constitution(P < 0.05).Conclusion Gender, family history, living environment, emotional state, and exercise habits were significant influencing factors of blood stasis constitution. Blood stasis constitution populations can pay more attention to these influencing factors in their daily life for the prevention and reconciliation of blood stasis constitution.

Astronomic background of global huge earthquakes at beginning of 21st century

Since the beginning of the 21st century,major earthquakes have frequently occurred worldwide.To explore the impact of astronomical factors on earthquakes,in this study,the statistical analysis method of correlation is used to systematically analyze the effects of astronomical factors,such as solar activity,Earth’s rotation,lunar declination angle,celestial tidal force,and other phenomena on M≥8 global earthquakes at the beginning of the 21st century.With regard to solar activity,this study focuses on the analysis of the 11-year and century cycles of solar activity.The causal relationship of the Earth’s rotation is not obvious in this work and previous works;in contrast,the valley period of the solar activity century cycle may be an important astronomical factor leading to the frequent occurrence of global earthquakes at the beginning of the 21st century.This topic warrants further study.

China's Constitution:Guarantee for People's Rights

The Communist Party of China, which represents the fundamental interests of the broadest possible masses of the people, has always attached much importance to the rights of the people and the safeguard measures. As early as in the New Democratic Revolution period, it adopted in Ruijin, Jiangxi Province, an Outline Constitution of the All-China Soviet Republic in January 1934. The document stipulated that all workers, peasants, soldiers and other labor populace and their families, irrespective of their gender, ethnic group or religion, are equal before the law of the Soviet and enjoy the right to work, supervision, education and the freedom

On China＇s Economy： A Tentative Research from a Dual Visual Angle

Most economists approach the economy of China from a single visual angle considering it as a special economic modality of transition economy. Based on the analysis from the single visual angle, the paper puts forward a dual visual angle treating China＇s economy as one of both transition and transformation features, and attempts to research it from this dual visual angle.

The Possibility of Angle Trisection （A Compass-Straightedge Construction） Kimuya M Alex

The objective of this paper is to provide a provable solution of the ancient Greek problem of trisecting an arbitrary angle employing only compass and straightedge （ruler）. （Pierre Laurent Wantzel, 1837） obscurely presented a proof based on ideas from Galois field showing that, the solution of angle trisection corresponds to solution of the cubic equation; x3 - 3x - 1 = 0, which is geometrically irreducible [1]. The focus of this work is to show the possibility to solve the trisection of an angle by correcting some flawed methods meant for general construction of angles, and exemplify why the stated trisection impossible proof is not geometrically valid. The revealed proof is based on a concept from the Archimedes proposition of straightedge construction [2, 3].

雷诺数和侧风对S型垂直轴风力机气动特性的影响

相较于工作在郊外良好风场的大型风力机,小型风力机易受城市风环境如低风速、高湍流度以及时变风速风向的影响。采用数值模拟手段研究了雷诺数和来流倾角对小型S型垂直轴风力机气动性能的影响。研究结果表明:S型风力机的气动性能对雷诺数不敏感,功率系数几乎不随雷诺数变化;侧风导致S型风力机的气动性能变差,静扭矩系数和功率系数降低,并且随着侧风来流倾角的增大,气动性能越差,侧风影响的流动机理一方面是来流倾角降低了水平速度分量,另一个方面是竖直速度分量减小了前进叶片的压力差,增加回转叶片的压力差,进一步加剧了气动性能的恶化。

Numerical and Experimental Study on Droplet Spreading Motion after Impingement Considering Dynamic Contact Angle with CCUP （CIP-Combined Unified Procedure） Method

The contact angle is one of important parameters to simulate droplet spreading and impingement phenomena on the surface. In the most numerical research, it is assumed constant value and it is implemented as boundary condition. However, contact angle is changed according to contact line velocity and time. Hence, for accurate simulation, dynamic contact angle which has various values as time elapsed is adopted. In the present study, the numerical analysis is performed on the droplet spreading phenomena considering dynamic contact angle function which is obtained from single droplet spreading experiment on the flat and bare surface. The CIP （cubic interpolated pseudo-particle） method by Yabe is used for analysis of interface between liquid and gas phases. The numerical results considering contact angle function which newly modeled as time and contact angle are compared with numerical results considering Hoffman＇s function and experimental data for range of Weber number which are 4.427 and 11.334. In contrast of numerical result considering Hoffman＇s function, the numerical result shows good agreement with experimental data as time elapsed in contact angle evolution, deformation of droplet spreading radius and height. Indeed, overall, the results display the increasing maximum spreading radius and the decreasing height as Weber numbers increased.

Implement Constitutional Principles to Uncover Tort Cases——An interview with Wang Zhenchuan, deputy chief procurator of the Supreme People's Procuratorate

EDITOR'S NOTE: Since May 2004, the people's procuratorates in China have concentrated their efforts on uncovering cases of encroaching upon human rights by government functionaries by abusing their power. The move has aroused extensive attention. On this, our staff reporter interviewed Deputy Chief Procurator Wang Zhenchuan, who is in charge of the campaign against human rights violations.

Forum on China's Move to Enshrine Human Rights in Constitution

China Society for Human Rights Studies (CSHRS) called a forum of experts and scholars on March 15 to discuss the significance of getting human rights protection enshrined in China’s fundamental law—the Constitution. Presided over by CSHRS President Zhou Jue, the forum was attended by CSHRS vice-presidents Yang Zhengquan and Dong Yunhu and more than 20 human rights experts and scholars from the

Clinical significance of Baumann's angle in the percutaneous pinning fixation for supracondylar fractures of the humerus in children

To evaluate the clinical significance of Baumann’s angle in the closed reduction and percutaneous pinning fixation for supracondylar fractures of the humerus in children.Methods There were 97 children (male 59,female 38,mean age of 6.8 years) with displaced supracondylar fracrtures of the humerus were treated in this hospital.Under fluoroscopy guidance,three-dimensional displacement of fractures was corrected by closed reduction.The percutaneous Kirschner wire pinning was applied only if the radiographs demonstrated that Baumann’s angle was less than 4 degree compared to that on the normal side.All of them were followed up for 34.5 months (range,12 to 48 months).Results There was one case with ulnar nerve palsy associated with the pinning.There were no Volkmann’s contracture in this group.X-ray examinations revealed an average 73.7 degrees of Baumann angle on the injured and 72.8 on uninjured side.An average 7.6 degrees of the carrying angle on the injured and 9.7 on uninjured side were also demonstrated by radiography.Five patients developed slight cubitus varus deformity.The result according to Flynn criteria were excellent in 85 patients (87.6%),good in 12 patients (12.4%).Conclusion The satisfactory results can be gained in children with displaced supracondylar fractures of the humerus by restoration of the normal Baumann angle and percutaneous pinning fixation.18 refs,2 figs.