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Tetrastigma hemsleyanum Diels & Gilg ex Diels is a liana plant with promising medicinal and ornamental values. Its calabash-shaped roots (CRs) are served as a traditional Chinese herb. However, it takes a long growth period to form CRs. In this study, three types of architectural roots, including fibrous roots (FRs), bar-shaped roots (BRs) and CRs, were employed as materials, and the characteristics of histo-anatomy and digital RNA-seq transcriptome profiles were analyzed. Among the three types of roots, the vascular bundles in FRs were intact, while some of the vascular bundles degenerated in BRs, and only few traces of vascular bundles existed in CRs. Meanwhile, no obvious cell inclusions were found in the cytoplasm of FRs, while a few inclusions were found in BRs, and abundant inclusions were detected in CRs, which might be the main source of medicinal components in roots. The transcriptome profiles and qRT-PCR validation indicated that seven upregulated genes, encoding xyloglucan glycosyltransferase, ACC oxidase, CYP711A1, SHORT-ROOT transcript factor, galacturonosyltransferas, WAT1 and WRKY, and two downregulated genes, encoding LRR receptor-like serine/threonine-protein kinase and CYP83B1, were probably involved in the formation and development of CRs. In addition, Gene Ontology terms of intrinsic component of membrane, integral component of membrane, cell periphery, membrane part, plasma membrane, membrane, intrinsic component of plasma membrane, cellular chemical homeostasis and plasma membrane part were probably related to the formation of CRs. Kyoto Encyclopedia of Genes and Genomes pathways related to the development of CRs probably included MAPK signaling pathway–plant, plant hormone signal transduction and circadian rhythm–plant. Our finding suggested a probable mode for the formation of CRs.

As a key component in the hot-dip galvanizing production line, the sink roller ends of the sliding bearing is affected by the high-temperature zinc liquid corrosion wear, which leads to frequent stop for maintenance. The galvanizing industry is looking for more suitable material for bearing to prolong the service life. To improve the corrosion and wear resistance of the sliding bearing, the laser cladding method was used to prepare the cobalt-based and iron-based coatings on the surface of the superalloy. In this paper, the high-temperature zinc liquid corrosion wear test was carried out on the alumina ceramic bushing and three kinds of metal sleeves (316L stainless steel, cobalt-based alloy, and iron-based alloy). By comparing and analyzing the corrosion and wear conditions of the three metal sleeves after the test, the main failure mechanisms were comprehensively analyzed.

The Pamir Salient and Southwestern Tien Shan belong to two different systems, which collided due to the continuous northward drift of the Indian Plate during the Cenozoic, resulting in a shortening of ~ 300 km. The uplift history and kinematic evolution of the Pamir-Southwestern Tien Shan remain unclear. In this study, we chose the 2025 m-thick Pakabulake formation in the East Wuqia section, at the southern-most margin of the Southwestern Tien Shan system, to obtain a high-resolution magnetostratigraphic record spanning ~ 16.61 Ma to ~ 9.78 Ma. Based on its high sedimentation rate, stable ca. E-W paleocurrents and stable magnetic susceptibility values, the nearby Southwestern Tien Shan was inferred to have undergone stable uplift during this period of sedimentation. Combining our results with the previous low-temperature thermochronology, magnetostratigraphy and re-calculated block rotations, we conclude that four episodic uplift events occurred in the Pamir-Southwestern Tien Shan during the Cenozoic, at times of ~ 50–40 Ma, ~ 35–16 Ma, ~ 11–7 Ma and

Different from material removal mechanism in metals, the main form of material removal of ceramics is brittle fracture removal. Previous studies on fracture mechanics for brittle materials basically do not involve cutting temperature, and only static crack systems are discussed, without considering the kinetic energy of crack extension; however, in real turning processes, the problem of crack extension is within the domain of dynamic fracture mechanics. Therefore, kinetic energy is considered in energy balance equations. The work of cutting force is converted into surface energy, strain energy, kinetic energy and heat energy. According to the law on the conservation of energy in fracture process, the theoretical equation of cutting temperature for brittle materials in turning is established. Then, turning experiments on fluorophlogopite ceramics are conducted to verify the applicability of the theoretical equation. The theoretical values of metal model, ceramic model and experimental values are compared. Results show that the theoretical value of metal model has a very large deviation when used to predict the cutting temperature of ceramics; whereas, the theoretical value of ceramic model is basically with the same changing tendency as the experimental value. This indicates that the established theoretical equation is practical.

The application of a hydrocyclone to recycle NGH and desand during NGH exploitation is a novel idea. The flow field and performance of this hydrocyclone is in the frontier of the research in this field and is unclear so far. This research aimed to reveal the flow field characteristics and performance of NGH downhole hydrocyclones. In this paper, flow field, solid phase particle volume distribution and separation efficiency were investigated according to the two objectives of NGH recovery efficiency and sand removal efficiency with different inlet velocities by computational fluid simulations (CFD)-FLUENT software. The results show that the short circuit flow contributed to the recovery of NGH. Axial velocity is a decisive factor in balancing the two objectives of NGH recovery efficiency and sand removal efficiency. In addition, the same as those in traditional hydrocyclones, the static pressure, tangential velocity and turbulence intensity play key roles in separation performance, hydrocyclone performance can be improved by increasing the inlet velocity. On the other hand, most separation efficiencies were greater than 80%, when the particle size was larger than 15 &micro, m, and the differential pressure was less than 0.6 MPa. Therefore, all the above results confirm that hydrocyclone has good performance in NGH exploitation, and the basis of its structural design and optimization are provided.

In order to improve estimation of the paleolatitude of the southern margin of Asia during the Late Cretaceous, as well as the constraints on the intracontinental convergence within Asia due to the India–Asia collision, we performed a combined geochronological and paleomagnetic investigation of Late Cretaceous red bed sequences and intercalated volcanic rocks from the Linzhou Basin in the Lhasa terrane (29.9°N/91.1°E). The results of potassium–argon (K–Ar) dating indicated that the basalt sequences are of Late Cretaceous age (68–75 Ma). Stepwise thermal demagnetization successfully isolated high unblocking-temperature characteristic directions from 10 red bed sites and 11 lava flow sites. Positive fold and reversal tests indicate a primary origin for the characteristic remanence of the red beds and basalt sites. The consistent inclination recorded in the red beds and basalt lava flows indicates that no significant compaction-related inclination shallowing has occurred in the red beds from the studied section. The tilt-corrected mean direction is D/I = 0.5°/20.2° with α 95 = 6.4° and N = 21 sites, corresponding to a paleopole at 70.5°N, 269.6°E with A 95 = 4.9°. The paleomagnetic results yield a paleolatitude of 10.4 ± 4.9°N for the southern margin of Asia in the Late Cretaceous. Compared with expected paleomagnetic directions from the Tethyan Himalaya and Asia, significant crustal shortening of 17.7 ± 5.5° (1960 ± 610 km) and 9.4 ± 4.7° (1040 ± 520 km), respectively, may have occurred between the southern margin of Asia and the Tethyan Himalaya, and within Asia, since the Late Cretaceous. Based on previous Cretaceous and Paleocene data from the Lhasa terrane, the latitude of the southern margin of Asia was located at a stable paleolatitudinal position (10°–15°N) during the Cretaceous and Paleocene.

Background WHO reported that HIV infection transmitted through injection drug use has declined; however, some studies have indicated that HIV infection is still high in this population in many countries and these changes are uncertain. We therefore aimed to evaluate the prevalence and trend of HIV infection in opioid and synthetic users in China. Methods We analysed the Drug User Surveillance Database of 3·3 million drug users reported nationwide in China between Jan 1, 2008, and Aug 1, 2016. We included 368 354 individuals who tested for HIV infection for the first time and persistently used opioid or synthetic drugs in our analysis of prevalence and trend of HIV infection. We grouped all participants into three groups according to their HIV status and positions in social networks: individual users (2·6 million users), HIV clustered network (8175 users), and non-HIV network (0·6 million users). The networks were tied by peer relationships, which was defined as both drug users who were reported at the same time, same location, and one of them nominated another user. Relationship of information was extracted from users' text document record, using breadth first search algorithm and the keywords matching method. The study was approved by Peking University Institutional Review Board. Findings The prevalence of HIV infection was estimated at 3·1% (7236 of 232 415) in opioid users, which was about six times more than in synthetic users (598 [0·4%] of 135 939; adjusted odds ratio [ORadj] 5·90, 95% CI 5·37–6·47), but reduced to 2·5 times in injection drug users (2·49, 1·28–4·85). From 2008 to 2015, the prevalence in opioid users presented a U-shaped trend, declining from 3·8% (691 of 18 336) in 2008 to 2·3% (745 of 31 980) in 2010 (ORadj 0·59, 95% CI 0·53–0·65) and increasing by 4·2% (1074 of 25 622) in 2015 (1·47, 1·33–1·62), while it maintained a stable increase in synthetic users from 0·2% (12 of 5047) in 2009 to 0·6% (234 of 40 336) in 2015 (ORadj 3·27, 95% CI 1·72–6·21). A total of 226 357 networks were mapped and 1401 networks were identified as HIV clustered networks, which covered 1962 HIV infections. The prevalence of HIV infection in HIV clustered network was 53·4% (1962 of 3675), which was about 25 times (ORadj 25·69, 95% CI 24·75–26·66) more than 2·1% (7990 of 384 430) in individual users. 75·8% (4324 of 5708) of users in the HIV clustered network were exposed to injection drug use compared with 15·2% (39 158 of 257 126) in the non-HIV cluster network and 26·9% (271 241 of 1 008 561) in individual users. Interpretation HIV infection in opioid users decreased from 2008–10 but subsequently increased from 2010–15, whereas HIV infection keeps increasing stably in synthetic users. Injection drug use in the HIV cluster network is still a high-risk factor and the effect of current strategies on HIV control in drug users, such as the needle and syringe programmes, need to be further estimated. Funding This study was supported by the National Natural Science Foundation of China (grant number 91546203 ) and the Chinese Ministry of Public Security ( 0716-1541GA590508 ).

To get global solution in multi-depots vehicle transshipment scheduling problem (MDVTSP), MDVTSP models are established. Genetic algorithm and particle swarm hybrid optimization is established to solve MDVTSP. The optimization course is as follow: first set up chromosome vector to get goods’ transshipment point, and assign goods to vehicles. Second, establish tabu matrix for ant colony optimization (ACO) to get vehicle route. Then evaluate and filtrate vehicle scheduling results by optimization aim, circulate until meet terminate qualification. Illustration results show that Hybrid arithmetic is effective for multi-depots vehicle transshipment scheduling problem.

Traffic assignment model is difficult to get global solution and impact its practical application. In order to solve this problem, ant colony optimization (ACO) was applied to multi-path traffic assignment problem. Tabu matrixes based on paths are established for ant colony optimization (ACO). Traffic assignment was processed by ACO, evaluated and filtered ant lines according to optimal aim, circulated until meet terminate qualification. A practical case illustrated that traffic assignment results better than reference optimal aim, and provide an algorithm to traffic assignment model.

Five high-speed compressor configurations are used to identify pre-stall pressure signal activity under clean and distorted inlet conditions, and under steady injection and controlled injection conditions. Through the use of a nonlinear statistic called correlation integral, variations in the compressor dynamics are identified from the pre-stall pressure activity far before variations (modal or pip) are observed visually in the wall static pressure measurements. The correlation integral not only discerns changing dynamics of these compressors prior to stall, but is now used to measure the strength of the tip flow field for these five high-speed compressors. Results show that correlation integral value changes dramatically when the stall inception is modal; and it changes less severely when the stall inception is through pip disturbances. This algorithm can therefore distinguish from the pre-stall pressure traces when a machine is more likely to stall due to pips versus modes. When used in this manner, the correlation integral thus provides a measure of tip flow strength. The algorithm requires no predisposition about the expected behavior of the data in order to detect changing dynamics in the compressor; thus, no pre-filtering is necessary. However, by band-pass filtering the data, one can monitor changing dynamics in the tip flow field for various frequency regimes. An outcome of this is to associate changes in correlation integral value directly with frequency specific events occurring in the compressor, i.e., blade length scale events versus long length scale acoustic events. The correlation integral provides a potential advantage over linear spectral techniques The correlation integral provides a potential advantage over linear spectral techniques because a single sensor is used for detection and analysis of the instabilities.

In order to solve wireless local area network (WLAN) security problem due to the open-wide nature of wireless radio and the improvement of computing power, a design of WLAN security program based on near field communication (NFC) is presented in this paper. In this paper, the importance of having access to handshake for WPA2 brute force is explained. The proposed design protects the four-way handshake by taking advantage of NFC short-range character to eliminate the risk of intercept. For implementation, Android system is selected as a mobile device development platform. The design is compatible with the IEEE 802.11i which ensures the massive expansion in the future. Furthermore, the design simplifies operations to improve users’ experience without much extra hardware cost and offers an option to the owner of WLAN to control the access physically, which benefits commercialization of NFC. From one perspective, this design can solve the wireless network security problem effectively.

To deal with assignment problem, particle swarm optimization vector present an assignment solution, multi-person assign to multi-job problem, bin packing problem, and multi-depots vehicle scheduling problem examples on particle swarm optimization solve assignment problem are developed. Illustration results show PSO is effective and offer a way to assignment problem.

To deal with people assign to job optimization problem in getting into local minima, people assign to job problem (PATJP) model and ant colony optimization (ACO) are developed for people assign to job optimization problem. In PATJP model, one people can assign to more than one job, and one job can be done by more than one people. People assign to job optimization is searched by ACO, optimization processes tend to get the global solution. Illustration results show that PATJP model and ACO algorithm are effective and offer a way to PATJP.

Through analyzing the characteristics of student tickets reservation, and under the condition of controlling the student tickets reservation information, a mathematic model of student ticket distribution model (STDM) is established. Particle swarm optimization (PSO) is established to solve STDM. In PSO, particle position matrix is set up, matrix's every column corresponds to a student, and matrix has two rows, the first row corresponds to train, and its elements are random train number that student will like to choose, second row correspond to date, and its elements are random date that student will like to choose. When students have the same train number and date pair, we can get train's students loads in one date. Through calculation example, this paper expounds the actual effect of the model.

Improved ant colony optimization (ACO) was applied to solve bin-packing problem. A tabu matrix bases on goods is established for ant colony optimization (ACO). Tabu matrix's every column corresponds to goods. Matrix has two rows, first row corresponds to goods load visit state, and second row corresponds to vehicle that ferries the goods. Ant state transfer probability is improved to solve bin-packing problem. According to ants tabu table, all the goods are searched by ants and satisfy the vehicle constrain. Illustrated with a practical case, ACO is feasible for bin-packing problem.

Logistics is divided into macroscopic logistics (also called social logistics) and microscopic logistics (also called enterprise logistics), according to microscope pattern and evolution line of TRIZ theory, this paper divides logistics into macroscopic logistics (social logistics), mesoscopic logistics (enterprise logistics) and microscopic logistics (individual logistics). we concentrate on microscopic logistics goods freight. We make use of integration pattern of evolution to integrate much single freight into super system. The selected technology is direct vehicular-customer communication (DV&CC) via radio transmission. It acts as intermediary in connection between vehicle and customer (v&c) in mobile ad hoc networks. In this way, we can make full use of nearby resource to meet customers' requirement at low cost, betimes and perfectly.

In order to solve bin-packing multi-depots vehicle scheduling problem (BPMDVSP), BPMDVSP model bases on goods is established. A tabu matrix bases on goods is established for ant colony optimization (ACO). Matrix has three rows, first row corresponds to goods start depot visit state, second row corresponds to goods end depot visit state, and third row corresponds to vehicle that ferries the goods. Tabu matrix's every column corresponds to goods, if goods qualities overload vehicle capacity, the goods column changes to goods bale numbers columns, and every column corresponds to a bale. The depot visit states in tabu matrix are set to avoid goods consignment mistake and single goods is ferried by different vehicles. State transfer rules are set when the two adjacent nodes are the same. According to ants tabu matrix, all the vehicle routs are searched by ants and satisfy the vehicle constrain. The illustration result shows model and algorithm can solve vehicle scheduling problem regardless goods whether in vehicle capacity.

This paper focuses on roles and their coordination of inter-organizational business process, a new model, role-based Petri net (RBPN), is presented based on theory of Petri net. And some important characteristics of this model are discussed. The application case indicates that this model has great applied value in inter-organizational business process modeling.

A multi-depots single vehicle routing problem (VRP) model based on goods were established to get global solution for VRP. Particle position matrix based on goods was established for particle swarm optimization (PSO) to sovle VRP model, and every matrix column corresponded to one goods. Matrix had two rows, first row corresponded to goods start point, and second row corresponded to goods end point. Matrix elements were random number between 0 and 1, and matrix elements sort rules were established to get single vehicle route. Then evaluated and filtered particles by objective function until met terminate condition. In this VRP model strategy, vehicle route to all goods was searched to avoid local minima. Illustration results show that VRP model and algorithm are effective and offer a way to multi-depots single vehicle routing problem.

Five high speed compressor configurations are used to identify pre-stall pressure signal activity under clean and distorted inlet conditions, and under steady injection and controlled injection conditions. Through the use of a nonlinear statistic called correlation integral, variations in the compressor dynamics are identified from the pre-stall pressure activity far before variations (modal or pip) are observed visually in the wall static pressure measurements. The correlation integral not only discerns changing dynamics of these compressors prior to stall, but is now used to measure the strength of the tip flow field for these five high speed compressors. Results show that correlation integral value changes dramatically when the stall inception is modal; and it changes less severely when the stall inception is through pip disturbances. This algorithm can therefore distinguish from the pre-stall pressure traces when a machine is more likely to stall due to pips versus modes. When used in this manner, the correlation integral thus provides a measure of tip flow strength. The algorithm requires no predisposition about the expected behavior of the data in order to detect changing dynamics in the compressor, thus no pre-filtering is necessary. However, by band-pass filtering the data, one can monitor changing dynamics in the tip flow field for various frequency regimes. An outcome of this is to associate changes in correlation integral value directly to frequency specific events occurring in the compressor, i.e. blade length scale events versus long length scale acoustic events. The correlation integral provides a potential advantage over linear spectral techniques because a single sensor is used for detection and analysis of the instabilities.Copyright © 1998 by ASME