基于角尺度的随机体在森林稳定性维持中的作用

【目的】探讨基于空间结构的森林稳定性维持机制,提出森林“随机体-稳定性”假说,为改善我国人工林稳定性提供科学参考。【方法】以我国不同气候带典型天然林为研究对象,利用林分空间结构参数——角尺度精细解译林木点格局,根据参照树及其最近4株相邻木构成的结构单元中相邻木的分布形式定义结构体,分析典型天然林结构体类型构成,揭示稳定性高的天然林普适性结构规律。【结果】天然林中的林木主要由随机木组成,其林木株数频率达55%,断面积占比高达50%以上;随机木构成天然林的主体,既与天然林地域分布和森林类型无关,也与天然林树种组成和格局类型无关。【结论】随机木是天然林稳定的基石,其在天然林中的主体构成是促使森林稳定性的关键。林分中随机体的架构形式使得随机木具有两面受光的邻体微环境,相较于均匀体,其中心木受相邻木的竞争压力更小,而相较于聚集体,随机木的相邻木之间挤压程度则更小,随机木及其邻体(随机体)相对来说承受的生存压力较小,在自然演替过程中能够获得更大的存活几率;随机体数量越多,森林群落越稳定。

Genetic differentiations between randomly and selectively bred pig populations in Yunnan,China

To assess the genetic diversity between randomly and selectively bred populations,we sequenced 438 bp of the mitochondrial DNA control region from 102 pigs.These samples represented four native pig breeds,one nucleus and one conservation herd from Yunnan,China.Twenty haplotypes with sixteen polymorphic sites were identified.The number of haplotypes in the nucleus herd of Saba pig and the conservation herd of Banna miniature pig were restricted to three and one,respectively,while the randomly bred pig populations exhibited over six haplotypes.Notably,haplotype diversity in randomly bred populations was significantly greater than the selectively bred populations（h=0.732 vs.0.425 and 0,exact test,P≤0.0036）.These findings demonstrate that selective breeding generated low genetic diversity compared to randomly bred pig breeds.A timely intervention and well programmed breeding approach would stop further genetic diversity reduction in the nucleus and conservation herds of native pig breeds.Otherwise,selective breeding would dramatically reduce genetic diversity in only several years,indicating that sharp contradictions exist between breeding,conservation and genetic diversity.Genetic relationships are discussed based on net genetic distances among pig populations.

Analysis of response time probability distribution of workflows

An evaluation approach for the response time probability distribution of workflows based on the fluid stochastic Petri net formalism is presented. Firstly, some problems about stochastic workflow net modeling are discussed. Then how to convert a stochastic workflow net model into a fluid stochastic Petri net model is described. The response time distribution can be obtained directly upon the transient state solution of the fluid stochastic Petri net model. In the proposed approach, there are not any restrictions on the structure of workflow models, and the processing times of workflow tasks can be modeled by using arbitrary probability distributions. Large workflow models can be efficiently tackled by recursively using a net reduction technique.

Analysis of BAC_5 mcAb-Related Epitope Using Random Peptide library

Objective To identify epitope relating to BAC 5 mcAb, a kind of monoclonal antibody (mcAb) located on the surface of nasopharyngeal carcinoma (NPC) cells. Methods Using BAC 5 mcAb as a selected target, the 3 rounds of biopanning to a 12 mer random peptide library (RPL) presented by M13 phages were carried out. The positive M13 phage clones were chosen and confirmed with sandwich ELISA for antibody capture and competitive assay. The exogenous DNA fragments in the positive/negative M13 phages were sequenced to deduce and compare the order of the amino acids of exogenous peptides among the phage clones. Results 77% (35/45) of the phages eluted from the 3rd round of biopnning could be captured by BAC 5 mcAb. The 3 kinds of the peptides were displayed by M13 phages from the 8 positive clones identified with competitive assay. The same character of '-P-V-'structure existed near N-terminus of the 3 different peptides, i.e. -H-Q-S-H-Y-P-Y-P-V-V-S-L- (4/8) -Q-N-Q-A-W-F-S-Q-P-V-R-M- (3/8) and T-Q-A-Y-K-G-F-P-V-L-P-S- (1/8) in comparison with the peptide ' -N-H-Q-S-T-F-W-Q-K-W-T-A-' displayed by M13 phages from the negative clones (6/6). Conclusion BAC 5 mcAb can recognize the 3 kinds of the peptides with-P-V-structure near N-terminus. These peptides mimic the structure of the epitope on the surface of NPC cells recognized by BAC 5 mcAb.

Nonequilibrium Statistical Physics Subject to the Anomalous Langevin Equation in Liouville Space

Considering that thermodynarmic irreversibility and hydrodynamic equations can not be derived rigorously and unifiedly from the Liouville equations, the anomalous Langevin equation in the Liouville space is proposed as a fundamental equation of statistical physics. This equation reflects that the law of motion of particles obeying reversible, deterministic laws in dynamics becomes irreversible and stochastic in thermodynamics. From this the fundamental equations of nonequilibrium thermodynamics, the principle of entropy increase and the theorem of minimum entropy production have been derived. The hydrodynamic equations, such as the generalized Navier-Stokes equation and the mass drift-diffusion equation etc. have been derived rigorously from the kinetic kinetic equation which is reduced from the anomalous Langevin equation in Liouville space. All these are unified and self consistent. But it is difficult to prove that entropy production density σ can never be negative everywhere for all the isolated inhomogeneous systems far from equilibrium.

Oil-gas reservoir lithofacies stochastic modeling based on one- to three-dimensional Markov chains

Stochastic modeling techniques have been widely applied to oil-gas reservoir lithofacies. Markov chain simulation~ however~ is still under development~ mainly because of the difficulties in reasonably defining conditional probabilities for multi-dimensional Markov chains and determining transition probabilities for horizontal strike and dip directions. The aim of this work is to solve these problems. Firstly~ the calculation formulae of conditional probabilities for multi-dimensional Markov chain models are proposed under the full independence and conditional independence assumptions. It is noted that multi-dimensional Markov models based on the conditional independence assumption are reasonable because these models avoid the small-class underestimation problem. Then~ the methods for determining transition probabilities are given. The vertical transition probabilities are obtained by computing the transition frequencies from drilling data~ while the horizontal transition probabilities are estimated by using well data and the elongation ratios according to Walther＇s law. Finally~ these models are used to simulate the reservoir lithofacies distribution of Tahe oilfield in China. The results show that the conditional independence method performs better than the full independence counterpart in maintaining the true percentage composition and reproducing lithofacies spatial features.

Natural history of heartburn:A 10-year population-based study

AIM： To study the natural history and prevalence of heartburn at a 10-year interval, and to study the effect of heartburn on various symptoms and activities. METHODS： A population-based postal study was carried out. Questionnaires were mailed to the same age- and gender-stratified random sample of the Icelandic population （aged 18-75 years） in 1996 and again in 2006. Subjects were classified with heartburn if they reported heartburn in the preceding year and/or week, based on the definition of heartburn. RESULTS： Heartburn in the preceding year was reported in 42.8% （1996） and 44.2% （2006） of subjects, with a strong relationship between those who experienced heartburn in both years. Heartburn in the precedingweek was diagnosed in 20.8%. There was a significant relationship between heartburn, dyspepsia and irritable bowel syndrome. IndMduals with a body mass index （BMI） below or higher than normal weight were more likely to have heartburn. Heartburn caused by food or beverages was reported very often by 20.0% of subjects. CONCLUSION： Heartburn is a common and chronic condition. Subjects with a BMI below or higher than normal weight are more likely to experience heartburn. Heartburn has a great impact on daily activities, sleep and quality of life.

A randomized open-label trial of on-demand rabeprazole vs ranitidine for patients with non-erosive reflux disease

AIM： To compare the efficacy of the proton-pump inhibitor, rabeprazole, with that of the H2-receptor antagonist, ranitidine, as on-demand therapy for relieving symptoms associated with non-erosive reflux disease （NEED）.METHODS： This is a single center, prospective, randomized, open-label trial of on-demand therapy with rabeprazole （group A） vs ranitidine （group B） for 4 wk. Eighty-three patients who presented to the American University of Beirut Medical Center with persistent gas- troesophageal reflux disease （GERD） symptoms and a normal upper gastrointestinal endoscopy were eligible for the study. Patients in group A （n = 44） were al-lowed a maximum rabeprazole dose of 20 mg twice daily, while those in group B （n = 39） were allowed a maximum ranitidine dose of 300 mg twice daily. Ef- ficacy was assessed by patient evaluation of global symptom relief, scores of the SF-36 quality of life （QoL） questionnaires, total number of pills used, and number of medication-free days.RESULTS： Among the 83 patients who were enrolled in the study, 76 patients （40 in the rabeprazole group and 36 in the ranitidine group） completed the 4-wk trial. Baseline characteristics were comparable between both groups. After 4 wk, there was no significant difference in the subjective global symptom relief between the rabeprazole and the ranitidine groups （71.4% vs 65.4%, respectively; P = 0.9）. There were no statistically significant differences between mean cumulative scores of the SF-36 QoL questionnaire for the two study groups （rabeprazole 22.40±27.53 vs ranitidine 17.28 ± 37.06; P = 0.582）. There was no significant difference in the mean number of pills used （rabeprazole 35.70±29.75 vs ranitidine 32.86±26.98; P = 0.66）. There was also no statistically significant difference in the mean number of medication-free days between both groups.CONCLUSION： Rabeprazole has a comparable efficacy compared to ranitidine when given on-demand for the treatment of NERD. Both medications were associated with improved quality of life.

2-D IMAGE-BASED VOLUMETRIC MODELING FOR PARTICLE OF RANDOM SHAPE

In this paper, an approach to predicting randomly-shaped particle volume based on its two- Dimensional （2-D） digital image is explored. Conversion of gray-scale image of the particles to its binary counterpart is first performed using backlighting technique. The silhouette of particle is thus obtained, and consequently, informative features such as particle area, centroid and shape-related descriptors are collected. Several dimensionless parameters are defined, and used as regressor variables in a multiple linear regression model to predict particle volume. Regressor coefficients are found by fitting to a randomly selected sample of 501 panicles ranging in size from 4.75mm to 25ram. The model testing experiment is conducted against a different aggregate sample of the similar statistical properties, the errors of the model-predicted volume of the batch is within ±2%.

Numerical Simulation of 2D and 3D Sloshing Waves in a Regularly and Randomly Excited Container

In this paper,various aspects of the 2D and 3D nonlinear liquid sloshing problems in vertically excited containers have been studied numerically along with the help of a modified-transformation.Based on this new numerical algorithm,a numerical study on a regularly and randomly excited container in vertical direction was conducted utilizing four different cases： The first case was performed utilizing a 2D container with regular excitations.The next case examined a regularly excited 3D container with two different initial conditions for the liquid free surface,and finally,3D container with random excitation in the vertical direction.A grid independence study was performed along with a series of validation tests.An iteration error estimation method was used to stop the iterative solver（used for solving the discretized governing equations in the computational domain） upon reaching steady state of results at each time step.In the present case,this method was found to produce quite accurate results and to be more time efficient as compared to other conventional stopping procedures for iterative solvers.The results were validated with benchmark results.The wave elevation time history,phase plane diagram and surface plots represent the wave nonlinearity during its motion.

Effects of repetitive transcranial magnetic stimulation on hypothalamic-pituitary-adrenal axis of patients with depression

Objective： To investigate the effects of sleep electroencephalogram-modulated repetitive transcranial magnetic stimulation （SEM-rTMS） and conventional rTMS （C-rTMS） on the activity of hypothalamic-pituitary-adrenal （HPA） axis in patients with depression. Methods： In a double-blind, randomized controlled trial, 164 patients diagnosed with depression were randomized to treatment with SEM-rTMS （n=57）, C-rTMS （n=55） or sham rTMS （n=52） for 30 rain every day for 10 d. Before and after treatment plasma concentrations of adrenocorticotropic hormone （ACTH） and cortisol （CORT） were measured, and the 24-item Hamilton Depression Rating Scale （HAMD-24） was used for assessment. Results： The HAMD-24 scores and plasma ACTH and CORT concentrations of these depressive patients before treatment were significantly different from those of the normal control group （P〈0.05）. The HAMD-24 scores and plasma ACTH and CORT concentrations in the SEM-rTMS group and conventional rTMS group were decreased significantly （P〈0.05）. There was a significant positive correlation between the HAMD-24 scores and plasma ACTH （n=240, r=0.105, P=0.048） and CORT concentrations （n-240, r=0.126, P=0.023） in the patients with depression before and after treatment. Conclusion： The antidepressant effect of rTMS, including SEM-rTMS, may be related to its decreasing HPA axis activity. （This trail was registered. No： ChiCTR-TRC-00000465）

Depinning Dynamics of Two-Dimensional Charged Colloids on a Random Laser-Optical Substrate

Using Langevin simulations, we. investigate the depinning dynamics of two-dimensional charged colloids on a random laser-optical substrate. With an increase in the strength of the substrate, we find a transition from crystal to smectic flows above the depinning. A power-law scaling relationship between average velocity and applied driving force could be obtained for both flows, and we find that the scaling exponents are no bigger than 1 for the crystal and are bigger than 1 for the smectic flows.

Association of traditional Chinese exercises with glycemic responses in people with type 2 diabetes:A systematic review and meta-analysis of randomized controlled trials

Background： There is increasing evidence showing the health benefits of various forms of traditional Chinese exercises （TCEs） on the glycemic profile in people with type 2 diabetes. However, relatively little is known about the combined clinical effectiveness of these traditional exercises. This study was designed to perform a systematic review and meta-analysis of the overall effect of 3 common TCEs （Tai Ji Quan, Qigong, Ba Duan Jin） on glycemie control in adults with type 2 diabetes. Methods： We conducted an extensive database search in Cochrane Library, EMBASE, PubMed, Web of Science, EBSCO, and China National Knowledge Infrastructure on randomized controlled trials published between April 1967 and September 2017 that compared any of the 3 TCEs with a control or comparison group on glycemic control. Data extraction was performed by 2 independent reviewers. Study quality was evaluated using the Coehrane Handbook for Systematic Reviews of Interventions, which assessed the risk of bias, including sequence generation, allocation concealment, blinding, completeness of outcome data, and selective outcome reporting. The resulting quality of the reviewed studies was characterized in 3 grades representing the level of bias： low, unclear, and high. All analyses were performed using random effects models and heterogeneity was quantified. We a priori specified changes in biomarkers of hemoglobin A1 c （in percentage） and fasting blood glucose （mmol/L） as the main outcomes and triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein-cholesterol, 2-h plasma glucose, and fasting plasma glucose as secondary outcomes.Results： A total of 39 randomized, controlled trials （Tai Ji Quan = 11; Qigong= 6; Ba Duan Jin= 22） with 2917 type 2 diabetic patients （aged 41-80 years） were identified. Compared with a control or comparison group, pooled meta-analyses of TCEs showed a significant decrease in hemoglobin Alc （mean difference （MD）= -0.67%; 95% confidence interval （CI）：-0.86% to-0.48%; p 〈 0.00001） and fasting blood glucose （MD = -0.66 mmol/L; 95%CI： -0.95 to -0.37 mmol/L; p 〈 0.0001）. The observed effect was more pronounced for interventions that were medium range in duration （i.e., 〉3-〈 12 months）. TCE interventions also showed improvements in the secondary outcome measures. A high risk of bias was observed in the areas of blinding （i.e., study participants and personnel, and outcome assessment）. Conclusion： Among patients with type 2 diabetes, TCEs were associated with significantly lower hemoglobin Alc and fasting blood glucose. Further studies to better understand the dose and duration of exposure to TCEs are warranted.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.

A Stochastic Description of Transition Between Granular Flow States

Two-dimensional granular flow in a channel with small exit is studied by molecular dyhamics simulations. We firstly define a key area near the exit, which is considered to be the choke area of the system. Then we observe the time variation of the local packing fraction and flow rate in this area for several fixed inflow rate, and find that these quantities change abruptly when the transition from dilute flow state to dense flow state happens. A relationship between the local flow rate and the local packing fraction in the key area is also given. The relationship is a continuous function under the fixed particle number condition, and has the characteristic that the flow rate has a maximum at a moderate packing fraction and the packing fraction is terminated at a high value with negative slope. By use of the relationship, the properties of the flow states under the fixed inflow rate condition are discussed in detail, and the discontinuities and the complex time variation behavior observed＇in the preexisting works are naturally explained by a stochastic process.

Recognition of newspaper printed in Gurumukhi script

In this work,a system for recognition of newspaper printed in Gurumukhi script is presented.Four feature extraction techniques,namely,zoning features,diagonal features,parabola curve fitting based features,and power curve fitting based features are considered for extracting the statistical properties of the characters printed in the newspaper.Different combinations of these features are also applied to improve the recognition accuracy.For recognition,four classification techniques,namely,k-NN,linear-SVM,decision tree,and random forest are used.A database for the experiments is collected from three major Gurumukhi script newspapers which are Ajit,Jagbani and Punjabi Tribune.Using 5-fold cross validation and random forest classifier,a recognition accuracy of 96.19%with a combination of zoning features,diagonal features and parabola curve fitting based features has been reported.A recognition accuracy of 95.21%with a partitioning strategy of data set(70%data as training data and remaining 30%data as testing data)has been achieved.

Near-Field Scattering Enhancement of Perylene Based Aggregates for Random Lasing

Strong near-field scattering enhancement (NFSE) of polyhedral oligomeric silsesquioxanes(POSS) nanoparticles (NPs) aggregates is found through physical simulation. An aggregation of N,N′-di-[3-(isobutyl polyhedral oligomeric silsesquioxanes) propyl] perylene diimide(DPP) which possesses POSS as scatteres experimentally performs strong NFSE, which confirms the physical simulation results. Moreover, coherent random laser is triggered from the DPP aggregates in carbon disulfide. It is the NFSE of POSS NPs connected to both ends of DPP through covalent bonds and the NFSE of their aggregation thanks to DPP’s aggregation that is responsible for the coherent random laser. So, this work develops a method to improve weak scattering of system through construction of molecules, and opens a road to a variety of novel interdisciplinary investigations, involving molecular designing for disordered photonics.

Fuzzy Random Reliability Analysis of Blocky Rock-Mass in Slopes

Slope stability assessment is a geotechnical problem characterized by many sources of uncertainty. In clas- sical reliability analysis, only the randomness of uncertainties is taken into account but the fuzziness of them is ignored. In this paper, a fuzzy probability approach and a fuzzy JC method are presented for the reliability analysis. The two methods have been applied to stability analysis of a certain slope of permanent ship lock in the Three-Gorges Project. The results obtained from these two methods are basically the same. However, compared with the fuzzy probability means, the fuzzy JC method can reflect the real situation better because it uses a fuzzy-based analysis applied to not only limit state equation but also mechanical parameters.

The Effects of Stochastic Characteristics of Materials on the Reliability of a Composite Ship Hull

The effects of stochastic characteristics of materials on the reliability of ship hulls made of composite materials under longitudinal moment were extensively studied using reliability and sensitivity calculations of a composite ship hull which was sagging.The reliability indices and failure probabilities of the ship in three kinds of failure modes (buckling,material failure,and ultimate collapse) were calculated by the surface response method and JC method.The importance factors of random variables in stochastic models,such as the model errors in predicting the ultimate longitudinal strength of ship and the longitudinal bending moment that the ship withstands,as well as the stochastic characteristics of materials in the models used,were calculated.Then,the effects of these random variables,including the stochastic characteristics of materials on the reliability index and the failure probability of ships which were sagging,were discussed with their importance factors.The results show that the effects of stochastic characteristics of materials on the reliability of ship hulls made of composite materials should be considered during the reliability assessment of composite ships.Finally,some conclusions and recommendations were given for high-speed ship design and safety assessment.

A randomized controlled trial of two chemotherapy regimens-paclitaxel liposome combined with platinum and paclitaxel combined with platinum in concurrent chemoradiotherapy for cervical carcinoma

Objective:The aim of the study was to compare the efficacy,side effect and influence on the survival rate of two chemotherapy regimens,paclitaxel liposome combined with platinum and paclitaxel combined with platinum,in concurrent chemoradiotherapy for cervical carcinoma.Methods:The 162 cases with primary cervical carcinoma diagnosed between January 2008 and November 2009 in Jiangxi Maternal and Child Health Hospital(China) were enrolled in this randomized controlled trial.Seventy-one cases were included in paclitaxel group and 91 in paclitaxel liposome group.And the chemotherapy doses were as follows:paclitaxel liposome and paclitaxel 135 mg/m2;cisplatin 80 mg/m2 or carboplatin AUC 4-6;then repeated every 21 days for two or three times.Radical radiotherapy was given to both groups at the same time.Efficacy was evaluated according to the tumor regression six months later and follow-up was done consistently.Results:The overall response rates of paclitaxel group and paclitaxel liposome group were 90.1% and 89 % respectively(P > 0.05).The one year cumulative survival was 91.4% for paclitaxel group and 89.2% for paclitaxel liposome group(P > 0.05).The incidence rates of adverse effects such as rash,gastrointestinal toxicity,bone marrow suppression and muscle/joint pain in paclitaxel liposome group were much lower than those in paclitaxel group(P < 0.05),while there was no difference regarding hair loss,hepatic function damage,peripheral neuritis and other aspects(P > 0.05).Conclusion:Paclitaxel liposome plus platinum is a safe and effective method for staging IIa-IV cervical carcinomas.While the long-term efficacy should be further observed.

Heterosis and Inbreeding Depression in Sunflower

Information on heterosis and inbreeding depression for yield and agronomic characters is essential for sunflower （Helianthus annuus L.） breeding programs. This research was conducted to evaluate heterosis and inbreeding depression for yield and agronomic characters of hybrids involving eight sunflower inbred lines. These inbred lines were crossed in 8×8 half diallel to obtain 28 F The 28 hybrids were self-pollinated to produce the F2 generation. The 8 parents, 28 F1 hybrids and 28 F2 populations hybrids were evaluated using a randomized complete block design with three replications at two locations in Nakhon Ratchasima （SUT Farm and National Corn and Sorghum Research Center） in 2009. Mid-parent heterosis and inbreeding depression were estimated for yield, head diamete oil content, 1,000-seed weight and plant height. Significant differences were found among the parents, F1 hybrids and F2 populations for all traits. F1 hybrid means were significantly higher than the parental means for all traits. In addition, F1 hybrids considerable heterosis and heterobeltiosis when compared with the mid-parent and better parents, respectively. Yield, showed oil content and plant height showed highly positive heterosis in F1 hybrids, ranging from 14.48 to 49.45%, 8.88 to 33.22% and 9.51 to 29 respectively. Similarly, heterobeltiosis were positive significant for yield （19.22 to 49.04%）, oil content （8.65 to 28.30%） and height （2,83 to 27.61%）. However, 1,000-seed weight showed a low level of heterosis in F1 hybrids （-9.36 to 8,07%） oil content, 1,000-seed weight and plant height in F2 populations were lower than their respective Fi hybrids the F2 populations was comparatively high for yield, oil content and plant height. The cross of lines 5A×for yield （49.45%） and 1,000 seed-weight （8.07%） but low 25%, plant Means for yield, Inbreeding depression in 2A gave the highest heterosis inbreeding depression for yield （10.06%）. Based on the mean performance and heterotic effects for seed yield, 1,000-seed weight and oil content, the inbred lines 2A and 5A are suggested for the development o hybrids,