Issues and opportunities of stem cell therapy in autoimmune diseases

The purpose of regenerative medicine is to restore or enhance the normal function of human cells, tissues, and organs. From a clinical point of view, the use of stem cells is more advantageous than differentiated cells because they can be collected more easily and in larger quantities, their proliferation capacity is more pronounced, they are more resistant in cell culture, their aging is delayed, they are able to form a number of cell lines, and they are able to promote vascularization of tissue carriers. The therapeutic use of stem cells for disease modification, immunomodulation, or regenerative purposes are undoubtedly encouraging, but most studies are still in their early stages, and the clinical results reported are not clear with regard to therapeutic efficacy and potential side effects. Uniform regulation of the clinical application of stem cells is also indispensable for this highly customizable, minimally invasive, individualized therapeutic method to become a successful and safe treatment alternative in many different autoimmune and autoinflammatory disorders.     

Cytotoxic T cell-induced apoptosis

Cytotoxic T lymphocytes and natural killer cells protect us against a variety of pathogens, and are involved in autoimmune diseases and transplant rejection. Granzyme B plays a major role in the mechanism used by these cytolytic effectors to destroy the target cells. This proteinase is produced by the effectors and stored within cytoplasmic granules. Upon interaction with the pathogenic cell the granzyme is transferred from the CTL to the target via directed exocytosis and subsequent receptor mediated endocytosis. It is interesting that cells that are deficient in expression of the receptor for granzyme are also resistant to CTL-     

Land Use/Cover Change and the Terrestrial Carbon Cycle in the Asia-Pacific Region

Current atmospheric CO_2 concentrations are the highest on record in the last half a millionyears and are expected to reach between 540 and 970 ppm over the next one hundred years. Thisunprecedented increase is linked to human activities including fossil fuel combustion anddeforestation. The increase in CO_2 concentrations, and to a lesser extent in other greenhouse gases,is linked to changes in climate patterns and variability, and to an average global warming of 0.6℃during the 20th Century (IPCC 2001). Changes in land use and cover are critical controls of the distribution and strength of carbon     

Current Status of Targets and Assays for Anti-HIV Drug Screening

HIV/AIDS is one of the most serious public health challenges globally. Despite the great efforts that are being devoted to prevent,treat and to better understand the disease,it is one of the main causes of morbidity and mortality worldwide. Currently,there are 30 drugs or combinations of drugs approved by FDA. Because of the side-effects,price and drug resistance,it is essential to discover new targets,to develop new technology and to find new anti-HIV drugs. This review summarizes the major targets and assays currently used in anti-HIV drug screening.     

A Procedure for the Design of Novel Assisting Devices for the Sit-to-Stand

The Sit-to-Stand （STS） is an activity most people perform numerous times daily. Standing up deals with the transition from two stabilized postures, namely seated to standing, with movement of all body segments except the feet. During the STS the body＇s Center of Gravity （COG） is moved upward from a sitting position to a standing position without losing balance and requiring a good coordination of many muscles. Three main phases of the STS movement can be recognized. One begins to stand up by inclining the upper body forward, which moves body mass toward the feet in order to maintain balance after lift-off. Prior to leaving the chair, hip and knee extensor muscles are activated to provide antigravity support for these joints, this action is commonly referred to as ＂weight shift＂. Finally; after leaving the chair, the leg and trunk joints are straightened to achieve upright stance. The STS task can be considered of major importance for impaired and elderly people to achieve minimal mo- bility and independence. In this paper we detail a procedure for the design of assisting devices to be used for the STS. In par- ticular, an experimental procedure is described firstly to track and record point trajectories and the orientation of the trunk during the STS. This analysis is then used to get information for the design of assisting devices. A proposal and simulation results are presented for a novel mechatronic system. In particular, for the case under study experimental tests are used to drive the actua- tion system for the reported simulation. A functional mechatronic scheme is then proposed to control the device during its operation.     

Conservation needs of amphibians in China: A review

The conservation status of all the amphibians in China is analyzed,and the country is shown to be a global priority for conservation in comparison to many other countries of the world.Three Chinese regions are particularly rich in amphibian diversity:Hengduan,Nanling,and Wuyi mountains.Sala-manders are more threatened than frogs and toads.Several smaller families show a high propensity to become seriously threatened:Bombinatoridae,Cryptobranchidae,Hynobiidae and Salamandridae.Like other parts of the world,stream-breeding,high-elevation forest amphibians have a much higher likeli-hood of being seriously threatened.Habitat loss,pollution,and over-harvesting are the most serious threats to Chinese amphibians.Over-harvesting is a less pervasive threat than habitat loss,but it is more likely to drive a species into rapid decline.Five conservation challenges are mentioned with recommendations for the highest priority research and conservation actions.     

Flip bifurcation and Neimark-Sacker bifurcation in a discrete predator prey model with harvesting

In this paper,a difference-algebraic predator prey model is proposed,and its complex dynamical behaviors are analyzed.The model is a discrete singular system,which is obtained by using Euler scheme to discretize a differential-algebraic predator-prey model with harvesting that we establish.Firstly,the local stability of the interior equilibrium point of proposed model is investigated on the basis of discrete dynamical system the­ory.Further,by applying the new normal form of difference-algebraic equations,center manifold theory and bifurcation theory,the Flip bifurcation and Neimark-Sacker bifur­cation around the interior equilibrium point are studied,where the step size is treated as the variable bifurcation parameter.Lastly,with the help of Matlab software,some numerical simulations are performed not only to validate our theoretical results,but also to show the abundant dynamical behaviors,such as period-doubling bifurcations,period 2,4,8,and 16 orbits,invariant closed curve,and chaotic sets.In particular,the corresponding maximum Lyapunov exponents are numerically calculated to corroborate the bifurcation and chaotic behaviors.     

Tracheal compliance and limit flow rate changes in a murine model of asthma

Trachea is the unique passage for air to flow in and out. Its tone is of importance for the respiration system. However, investigation on how tracheal tone changes due to asthma is limited. Aiming at studying how the mechanical property changes due to asthma as well as the compliance and flow limitation, the following methods are adopted. Static and passive pressure-volume tests of rats' trachea of the asthmatic and control groups are carried out and a new type of tube law is formulated to fit the experimental data, based on which changes of compliance and limit flow rate are investigated. In order to give explanation to such changes, histological examinations with tracheal soft tissues are made. The results show that compliance, limit flow rate and material constants included in the tube law largely depend on the longitudinal stretching ratio. Compared with the control group, the tracheal compliance of asthmatic animals decreases significantly, which results in an increased limit flow rate. Histological studies indicate that asthma can lead to hyperplasia/hypertrophy of smooth muscle cells, and increase elastin and collagen fibres in the muscular membrane. Though decreasing compliance increases sta- bility, during the onset of asthma, limit flow rate is much smaller due to the lower transmural pressure. Asthma leads to a stiffer trachea and the obtained results reveal some aspects relevant to asthma-induced tracheal remodelling.     

In vivo skin penetration and metabolic path of quantum dots

The skin is the largest organ of the body and is a potential route of exposure to sunscreens and cosmetics containing nanoparticles;however,the permeability of the skin to these nanoparticles is currently unknown.In this paper,we studied the transdermal delivery capacity through mouse skin of water-soluble CdSeS quantum dots(QDs) and the deposition of these QDs in the body.QD solution was coated onto the dorsal hairless skin of male ICR mice.Fluorescence microscopy and transmission electron microscopy(TEM) were used to observe the distribution of QDs in the skin and organs,and inductively coupled plasma-mass spectrometry(ICP-MS) was used to measure the 111Cd content to indicate the concentration of QDs in plasma and organs.Experimental results indicate that QDs can penetrate into the dermal layer and are limited to the uppermost stratum corneum layers and the hair follicles.Through blood circulation,QDs deposit mostly in liver and kidney and are difficult to clear.111Cd concentration was greater than 14 ng g-1 in kidney after 120 h after 0.32 nmol QDs was applied to a mouse.These results suggest that QDs have in vivo transdermal delivery capacity through mouse skin and are harmful to the liver and kidney.     

New species of the isolated Psaroniaceous rachis from the Early Permian in China

A new kind of marattialean raches are reported from the coal balls in Coal Seam No.7 in the upper part of the Taiyuan Formation （early Early Permian） from Taiyuan, Shanxi, China and are assigned to the genus Stipitopteris Grand＇Eury （Psaroniaceae）. The present specimens are different from all six reported species of the genus, and are therefore proposed as a new species： Stipitopteris shanxiensis. The raches of the new species are generally dorsi-ventrally flattened. The main raches usually exhibit scales of different forms on their surface. Beneath the epidermis is a zone of parenchymatous cells, some of which contain tannin-like contents. Inside this is a zone of small sclerenchymatous cells. Inward are the ground tissue and vascular bundles. The vascular bundles are continuous and are in two circles： the outer circle assumes a transversely elliptical shape with the gap and pinna trace, and the inner circle assumes a shallow C.shape with inrolled ends. The ground tissue located at the inner side of the vascular bundle is composed of thicker-walled parenchymatous cells. The cells of the ground tissue are vertically elongated in longitudinal sections. Subordered raches are smaller and have simpler structures than the main raches. The parenchyma zone beneath the epidermis is thinner, usually one to two cells wide and the sclerenchyma zone is usually absent. The scales are poorly developed and there is only one C-shaped vascular bundle. The new species is comparable to the crosiers of Psaroniaceae of the Euramerican Flora in some aspects, for example, it has a dorsi-ventrally flattened rachis and scales on the surface of the rachis. However, the other features and the preservative conditions of the present specimens indicate that they are not crosiers, but fully developed or mature raches. The new species is the first well-studied anatomically-preserved rachis of Psaroniaceae from the Cathaysian Flora and bears significance not only in understanding the anatomy and taxonomy of Psaroniaceae in the Cathaysian Flora, but also in the relationship between the Euramerican Flora and the Cathaysian Flora.     

Clonal Selection Based Memetic Algorithm for Job Shop Scheduling Problems

A clonal selection based memetic algorithm is proposed for solving job shop scheduling problems in this paper. In the proposed algorithm, the clonal selection and the local search mechanism are designed to enhance exploration and exploitation. In the clonal selection mechanism, clonal selection, hypermutation and receptor edit theories are presented to construct an evolutionary searching mechanism which is used for exploration. In the local search mechanism, a simulated annealing local search algorithm based on Nowicki and Smutnicki＇s neighborhood is presented to exploit local optima. The proposed algorithm is examined using some well-known benchmark problems. Numerical results validate the effectiveness of the proposed algorithm.     

Development of a Bionic Hexapod Robot for Walking on Unstructured Terrain

This paper reports the design methodology and control strategy in the development of a novel hexapod robot HITCR-II that is suitable for walking on unstructured terrain. First, the entire sensor system is designed to equip the robot with the perception of external environment and its internal states. The structure parameters are optimized for improving the dexterity of the robot. Second, a foot-force distribution model and a compensation model are built to achieve posture control. The two models are capable of effectively improving the stability of hexapod walking on unstructured terrain. Finally, the Posture Control strategy based on Force Distribution and Compensation （PCFDC） is applied to the HITCR-II hexapod robot. The experimental results show that the robot can effectively restrain the vibration of trunk and keep stable while walking and crossing over the un- structured terrains.     

Optimal Control of a Mackerel-Mimicking Robot for Energy Efficient Trajectory Tracking

A robotic fish, BASEMACK1, is designed and fabricated by mimicking the shape of a live mackerel. Three DC servo-motors are serially linked together and actuated to mimic the mackerel＇s Carangiform motion. Hydrodynamic characteristics of a fish-mimetic test model are experimentally identified and utilized in order to numerically simulate fish swimming. The discrete set of kinematic and dynamic parameters are obtained by considering required horizontal and lateral forces and minimum energy consumption. Using the optimized parameter set, optimal control of the robot is studied.     

Programmed Cell Death in Relation to Petal Senescence in Ornamental Plants

Cell death is a common event in all types of plant organisms. Understanding the phenomenon of programmed cell death (PCD) is an important area of research for plant scientists because of its role in senescence and the post-harvest quality of ornamentals, fruits, and vegetables. In the present paper, PCD in relation to petal senescence in ornamental plants is reviewed. Morphological, anatomical, physiological,and biochemical changes that are related to PCD in petals, such as water content, sink-source relationships,hormones, genes, and signal transduction pathways, are discussed, Several approaches to improving the quality of post-harvest ornamentals are reviewed and some prospects for future research are given.     

NOTES ON THE GENUS NEOPODOCINUM IN CHINA,WITH DESCRIPTIONS OF TWO NEW SPECIES(ACARINA:MACROCHELIDAE)

The present paper deals with four species of the genus Neopodocinumoff scarabaeid beetles in China, among them Neopodocinum sinicum and N.gunnanense are new to science, the deutonymph of N. dehongense is descri-bed for the first time, and N. vanderhammeni is collected in southwestChina for the first time. The type materials are deposited in the Depart-ment of Parasitology, Guiyang Medical College.Keys to the females and malesof 6 known Chinese species of the genus Neopodocinum are appended.     

Bio-Inspired Electromagnetic Protection Based on Neural Information Processing

Electronic systems are vulnerable in electromagnetic interference environment. Although many solutions are adopted to solve this problem, for example shielding, filtering and grounding, noise is still introduced into the circuit inevitably. What impresses us is the biological nervous system with a vital property of robustness in noisy environment. Some mechanisms, such as neuron population coding, degeneracy and parallel distributed processing, are believed to partly explain how the nervous system counters the noise and component failure. This paper proposes a novel concept of bio-inspired electromagnetic protec- tion making reference to the characteristic of neural information processing. A bionic model is presented here to mimic neuron populations to transform the input signal into neural pulse signal. In the proposed model, neuron provides a dynamic feedback to the adjacent one according to the concept of synaptic plasticity. A simple neural circuitry is designed to verify the rationality of the bio-inspired model for electromagnetic protection. The experiment results display that bio-inspired electromagnetic pro- tection model has more power to counter the interference and component failure.     

The Bionic Anticipation of Natural Disasters

After major natural disasters, such as the recent earthquake-tsunami event in South Asia, reports appear about the mysterious ability of animals to anticipate and to escape the impending danger. This is an opportunity to recall the long history of this phenomenon in the traditions of different civilizations, to evaluate Chinese efforts, 30-40 years ago, to use this phenomenon for earthquake prediction, and to judge its state of acceptance in modem science. An effort is made to introduce this phenomenon as a research field of modem bionics. The timing is favorable since, increasingly, infrared thermal anomalies, monitored from satellite, suggesting litho-atmospheric processes, are found to precede earthquakes. They were unexpected by seismologists and are here suggested to essentially reflect the energy conversion patterns responsible for the signals monitored by animals. The aim is to learn from animals in the long term how natural disasters can better be anticipated, and how simple technical warning systems can be developed. Some challenges are analyzed. One is interpretation of the nature of energy release prior to the main earthquake disaster resulting in ＂macro-anomaly＂ precursors, another is better to understand the effect on animal senses. The role of non-linear cooperative phenomena including tsunamitype waves is emphasized.     

Wrinkled petals and stamens 1, is required for the morphogenesis of petals and stamens in Lotus japonicus

Although much progress has been made in understanding how floral organ identity is determined during the floral development, less is known about how floral organ is elaborated in the late floral developmental stages. Here we describe a novel floral mutant, wrinkled petals and stamens1 （wps1）, which shows defects in the development of petals and stamens. Genetic analysis indicates that wpsl mutant is corresponding to a single recessive locus at the long arm of chromosome 3. The early development of floral organs in wpsl mutant is similar to that in wild type, and the malfunction of the mutant commences in late developmental stages, displaying a defect on the appearance of petals and stamens. In the mature flower, petals and stamen filaments in the mutant are wrinkled or folded, and the cellular morphology under L1 layer of petals and stamen filaments is abnormal. It is found that the expression patterns of floral organ identity genes are not affected in wpsl mutants compared with that of wild type, consistent with the unaltered development of all floral organs. Furthermore, the identities of epidermal cells in different type of petals are maintained. The histological analysis shows that in wpsl flowers all petals are irregularly folded, and there are knotted structures in the petals, while the shape and arrangement of inner cells are malformed and unorganized. Based on these results, we propose that Wpsl acts downstream to the class B floral organ identity genes, and functions to modulate the cellular differentiation during the late flower developmental stages.