Global Warming： Can Existing Reserves Really Preserve Current Levels of Biological Diversity？

Peleoecologlcel evidence end peleoclimatlc records indicate that there wee e plant polewerd migration in latitude and an upward shift In elevation with increased temperatures after the last glaciation. Recent studies have shown that global warming over the past 100 years has been having a noticeable effect on living systems. Current global warming Is causing a poleward and upward shift In the range of many plants and animals. Climate change, In connection with other global changes, is threatening the survival of a wide range of plant and animal species. This raises the question： can existing reserves really preserve current levels of biological diversity In the long term given the present rapid pace of climate change？ The present paper deals with this question In the context of the responses of plants and animals to global climate change, based on a literature review. Consequently, we recommend expanding reserves towards the poles and/or towards higher altitudes, to permit species to shift their ranges to keep pace with global warming.     

Immunosenescence and age-related viral diseases

Immunosenescence is described as a decline in the normal functioning of the immune system associated with physiologic ageing.Immunosenescence contributes to reduced efficacy to vaccination and increased susceptibility to infectious diseases in the elderly.Extensive studies of laboratory animal models of ageing or donor lymphocyte analysis have identified changes in immunity caused by the ageing process.Most of these studies have identified phenotypic and functional changes in innate and adaptive immunity.However,it is unclear which of these defects are critical for impaired immune defense against infection.This review describes the changes that occur in innate and adaptive immunity with ageing and some age-related viral diseases where defects in a key component of immunity contribute to the high mortality rate in mouse models of ageing.     

Adaptive Control for Passive Kinesiotherapy ELLTIO

Exoskeletons are mechatronic devices used to increase human muscle strength and resistance. In the last decade these devices have become a very useful tool to assist active kinesiotherapy. This paper presents the design of exoskeleton focused on the rehabilitation of ankle and knee for the right leg. The construction of prototype like Exoskeleton for Lower Limb Training with Instrumented Orthoses （ELLTIO） using Series Elastic Actuator （SEA） to reduce the effort in the human joints, and a control law to perform a rehabilitation routine using an adaptive control scheme were first implemented in simulation to verify the control strategy and make a real rehabilitation test. The adaptive control law is proposed with the intention that the exoskeleton can adapt to user parameters at the time when performing the exercise. The results show the parameters estimation and tracking trajectory for the exoskeleton were proposed, and this trajectory could be a routine rehabilitation proposed by the therapist.     

Evolutionary implications of Avian Infectious Bronchitis Virus （AIBV） analysis

For developing efficient vaccines, it is essential to identify which amino acid changes are most important to the survival of the virus. We investigate the amino acid substitution features in the Avian Infectious Bronchitis Virus （AIBV） antigenic domain of a vaccine serotype （DE072） and a virulent viral strain （GA98） to better understand adaptive evolution of AIBV. In addition, the SARS Coronavirus （SARS-CoV） was also analyzed in the same way. It is interesting to find that extreme comparability exists between AIBV and SARS in amino acid substitution pattern. It suggests that amino acid changes that result in overall shift of residue charge and polarity should be paid special attention to during the development of vaccines.     

黑龙江小兴安岭地区黄鼬夏冬季毛皮性状比较

Coat characteristics of seasonal molting mammals reveal significant seasonal variation as an adaptive strategy to cope with seasonal climate changes. However, the adaptive significance of such morphological variation has not yet been addressed. We analyzed seasonal variation of microscopic indices of hair and skin of adult Siberian weasels (Mustela sibirica manchurica Brass) from the Tonghe forest area of the Xiaoxing’anling Mountains, Heilongjiang. Skins from 8 males and 8 females were collected from summe...     

Molecular mechanisms of adaptive evolution in wild animals and plants

Wild animals and plants have developed a variety of adaptive traits driven by adaptive evolution, an important strategy for species survival and persistence. Uncovering the molecular mechanisms of adaptive evolution is the key to understanding species diversification, phenotypic convergence, and inter-species interaction. As the genome sequences of more and more non-model organisms are becoming available, the focus of studies on molecular mechanisms of adaptive evolution has shifted from the can...     

An Approach for Searching Insertions in Bacterial Genes Leading to the Phase Shift of Triplet Periodicity

The concept of the phase shift of triplet periodicity (TP) was used for searching potential DNA insertions in genes from 17 bacterial genomes. A mathematical algorithm for detection of these insertions has been developed. This approach can detect potential insertions and deletions with lengths that are not multiples of three bases, especially insertions of relatively large DNA fragments (>100 bases). New similarity measure between triplet matrixes was employed to improve the sensitivity for detecting the TP phase shift. Sequences of 17,220 bacterial genes with each consisting of more than 1,200 bases were analyzed, and the presence of a TP phase shift has been shown in ~16% of analysed genes (2,809 genes), which is about 4 times more than that detected in our previous work. We propose that shifts of the TP phase may indicate the shifts of reading frame in genes after insertions of the DNA fragments with lengths that are not multiples of three bases. A relationship between the phase shifts of TP and the frame shifts in genes is discussed.     

Global view of bionetwork dynamics: adaptive landscape

Based on recent work, I will give a nontechnical brief review of a powerful quantitative concept in biology, adaptive landscape, ini- tially proposed by S. Wright over 70 years ago, reintroduced by one of the founders of molecular biology and by others in different bio- logical contexts, but apparently forgotten by modem biologists for many years. Nevertheless, this concept finds an increasingly important role in the development of systems biology and bionetwork dynamics modeling, from phage lambda genetic switch to endogenous net- work for cancer genesis and progression. It is an ideal quantification to describe the robustness and stability of bionetworks. Here, I will first introduce five landmark proposals in biology on this concept, to demonstrate an important common thread in theoretical biology. Then I will discuss a few recent results, focusing on the studies showing theoretical consistency of adaptive landscape. From the perspec- tive of a working scientist and of what is needed logically for a dynamical theory when confronting empirical data, the adaptive landscape is useful both metaphorically and quantitatively, and has captured an essential aspect of biological dynamical processes. Though at the theoretical level the adaptive landscape must exist and it can be used across hierarchical boundaries in biology, many associated issues are indeed vague in their initial formulations and their quantitative realizations are not easy, and are good research topics for quantitative biologists. I will discuss three types of open problems associated with the adaptive landscape in a broader perspective.     

Effects of SO2 derivatives on sodium currents in acutely isolated rat hippocampal lead-exposed neurons

In this study, the effects of acute SO_2 derivatives and chronic lead exposure together on sodium cur-rents (INa) were investigated in acutely isolated rat hippocampal neurons by using the whole-cell patch clamp techniques. We found that chronic lead exposure hardly reduced the amplitudes of INa. In the normal condition, sodium current started to appear at around ?70 mV, and reached the peak current at around ?40 mV. After chronic lead exposure, the data changed to ?70 and ?30 mV. After adding SO2 derivatives, the data changed to ?80 and ?40 mV, respectively. SO_2 derivatives caused a significant in-crease of INa in hippocampal chronic-lead exposed neurons. Chronic lead exposure induced a right shift of the activation curve and a left shift of the inactivation curve of sodium channels. SO_2 derivatives caused negative shifts of the activation and inactivation curves of INa in hippocampal chronic-lead ex-posed neurons. Lead exposure put off the time reaching the peak of INa activation. SO_2 derivatives in-creased the time constants of inactivation after lead exposure. The interaction of lead and SO_2 deriva-tives with voltage-dependent sodium channels may lead to changes in electrical activity and contribute to worsening the neurotoxicological damage.     

Cytokines as critical co-stimulatory molecules in modulating the immune response of natural killer cells

Cytokines are involved in directing the activation of natural killer （NK） cells. NK cells are involved in the recognition of cells that have been altered; thus they do not recognize specific insults to the host, but when activated, are capable of destroying infected cells directly, as well as promoting the recruitment and response of the other components of the immune system by the release of cytokines and chemokines. It is these properties that have made NK cells a critical part of innate immunity and adaptive immunity, and they play a principal role linking innate and adaptive immunity by the recruitment of an adaptive immune response to an innate immune reaction.     

Physiological behaviour of Arthrospira (Spirulina) maxima during acclimation to changes in irradiance

The physiological behaviour of Arthrospira (Spirulina) maxima during acclimation to sudden changes in irradiance from high (HL) to low light (LL) and vice versa was studied by following parameters concerning growth rate, pigment, carbohydrate and protein cell contents. Applying first order kinetics, the specific acclimation rates for the parameters considered were calculated. During HL to LL shift, pigments increased to compensate for a reduction in growth irradiance in order to maintain relatively high growth rates, whereas carbohydrates decreased at the highest rate. The synthesis of phycobiliproteins proceeded at a rate similar or little higher than that of chlorophyll a, indicating their importance in the light harvesting at low irradiance. During LL to HL shift, carbohydrate biosynthesis was increased, whereas pigment and protein cell contents decreased. The kinetic analysis suggested that the pigment decrease could be accounted for both by dilution through growth and in vivo degradation. During this transition, the initially high cell pigment content gave rise to a very heavy carbohydrate synthesis, which for a short time, after the shift to HL conditions, overshot the final steady-state. In the same period the specific growth rate also increased notably, overshooting the μmax. The acclimation rates of the measured parameters were faster during LL to HL transition then during the reverse. The physiological response of A. maxima during the acclimation to sudden irradiance shifts points out the ability of this cyanobacterium to alter light harvesting and highlights again the key role of carbohydrates when the cells underwent an energy crisis during down-shift. This revised version was published online in August 2006 with corrections to the Cover Date.     

The response of peatlands to climate warming: A review

Peatlands hold a large portion of the Earth’s terrestrial organic carbon and serve as important pools in the global carbon cycle. Due to their strong feedbacks, peatlands are one of the most important ecosystems with respect to climate warming. This paper reviews the effects of climate warming on peatland ecosystems. Climate warming will shift the point in time when vascular peatland plants flower and reach maximum biomass to an earlier date. Flower production for some plants will increase, but how the phenology of peatland bryophytes will react is still unknown. Climate warming may increase productivity of peatlands, especially ombrotrophic Sphagnum bogs, but in the long run the negative effects from decreased water availability may prevail. Climate warming will change the basic characteristics of peatlands: their wetness and the related cold environment and nutrient shortage. By increased mineralization and nitrogen and phosphorus availability, climate warming will facilitate the growth of vascular plants. This will suppress endangered plant species (which usually grow in low-productive, phosphorus-limited habitats) and lead to a change in vegetation composition and a decrease in peatland biodiversity. Climate warming will change the competitive balance between bryophytes and between Sphagnum and vascular plants. Climate warming in the Late Pleistocene facilitated the initiation of peatland formation, but most current experiments show an obvious tendency for climate warming to drive many peatlands to regressive succession with a shift in dominance from Sphagnum to vascular plants. This change in vegetation will increase the flux of CH₄ and possibly also CO₂. The effect of accelerated peat decay as a result of climate warming will vary between types of peatlands. Since climate warming will generally enhance peat respiration more than net primary production, more and more peatlands will become carbon sources rather than carbon sinks, which will aggravate climate warming by positive feedback. Finally, this paper addresses some problems with current manipulative experimental studies on peatland response to climate warming and makes suggestions for further studies.     

Changes of intracellular Na~ concentration in erythrocytes caused by pulsed electrical field

Changes of sodium ionic concentration of human erythrocytes applied to pulsed electrical field (PEF) were studied by using shift reagent and NMR spectroscopy. The results show that the concentration of intracellular Na increases with the increasing intensity of PEF when the erythrocytes are applied to PEF with higher intensities. The relationship between intracellular Na concentrations and the intensities of PEF does not follow linear or exponen-tial behavior. As the intensities increase, the intracellular Na concentrations increase even faster by an exponential curve. However under effects of PEF at lower intensities, intracellular Na concentration decreases. Ouabain can in-hibit the decrease of intracellular Na concentration, and the inhibition increases with the increasing concentration of ouabain, suggesting that Na , K -ATPase on cell membrane can be activated by PEF at lower intensities. Direct measurement of activities of the enzyme by using Malachite green method has confirmed this observatio     

An Approach for Adaptive Limbless Locomotion Using a CPG-Based Reflex Mechanism

Animals＇ free movement in natural environments has attracted many researchers to explore control methods for bio-inspired robots. This paper presents a novel reflex mechanism based on a Central Pattern Generator （CPG） for adaptive locomotion of limbless robots. First, inspired by the concept of reflex arc, the reflex mechanism is designed on a connectionist CPG model. Since the CPG model inspired by the spinal cord of lampreys is developed at the neuron level, it provides a possible natural solution for sensory reflex integration. Therefore, sensory neurons that bridge the external stimuli and the CPG model, together with the concept of reflex arc, are utilized for designing the sensory reflex mechanism. Then, a border reflex and a body reflex are further developed and applied on the ends and the middle part of a limbless robot, respectively. Finally, a ball hitting scenario and a corridor passing scenario are designed to verify the proposed method. Results of simulations and on-site experiments show the feasibility and effectiveness of the reflex mechanism in realizing fast response and adaptive limbless locomotion.     

The response of peatlands to climate warming: A review

Peatlands hold a large portion of the Earth’s terrestrial organic carbon and serve as important pools in the global carbon cycle. Due to their strong feedbacks, peatlands are one of the most important ecosystems with respect to climate warming. This paper reviews the effects of climate warming on peatland ecosystems. Climate warming will shift the point in time when vascular peatland plants flower and reach maximum biomass to an earlier date. Flower production for some plants will increase, but how the phenology of peatland bryophytes will react is still unknown. Climate warming may increase productivity of peatlands, especially ombrotrophic Sphagnum bogs, but in the long run the negative effects from decreased water availability may prevail. Climate warming will change the basic characteristics of peatlands: their wetness and the related cold environment and nutrient shortage. By increased mineralization and nitrogen and phosphorus availability, climate warming will facilitate the growth of vascular plants. This will suppress endangered plant species (which usually grow in low-productive, phosphorus-limited habitats) and lead to a change in vegetation composition and a decrease in peatland biodiversity. Climate warming will change the competitive balance between bryophytes and between Sphagnum and vascular plants. Climate warming in the Late Pleistocene facilitated the initiation of peatland formation, but most current experiments show an obvious tendency for climate warming to drive many peatlands to regressive succession with a shift in dominance from Sphagnum to vascular plants. This change in vegetation will increase the flux of CH₄ and possibly also CO₂. The effect of accelerated peat decay as a result of climate warming will vary between types of peatlands. Since climate warming will generally enhance peat respiration more than net primary production, more and more peatlands will become carbon sources rather than carbon sinks, which will aggravate climate warming by positive feedback. Finally, this paper addresses some problems with current manipulative experimental studies on peatland response to climate warming and makes suggestions for further studies.     

Molecular mechanisms of insect adaptation to plant defense： Lessons learned from a Bruchid beetle

Plants can accumulate, constitutively and/or after induction, a wide variety of defense compounds in their tissues that confer resistance to herbivorous insects. The naturally occurring plant resistance gene pool can serve as an arsenal in pest management via transgenic approaches. As insect-plant interaction research rapidly advances, it has gradually become clear that the effects of plant defense compounds are determined not only by their toxicity toward target sites, but also by how insects respond to the challenge. Insect digestive tracts are not passive targets of plant defense, but often can adapt to dietary challenge and successfully deal with various plant toxins and anti-metabolites. This adaptive response has posed an obstacle to biotechnology-based pest control approaches, which underscores the importance of understanding insect adaptive mechanisms. Molecular studies on the impact of protease inhibitors on insect digestion have contributed significantly to our understanding of insect adaptation to plant defense. This review will focus on exposing how the insect responds to protease inhibitors by both qualitative and quantitative remodeling of their digestive proteases using the cowpea bruchid-soybean cysteine protease inhibitor N system.     

Effect of phosphatidylglycerol on conformation and micro-environment of tyrosyl residue in photosystem II

The structural aspects in the interaction of phosphatidylglycerol (PG) with photosystem II (PSIl), mainly the effect of PQ on conformation and microenvironment of tyrosine residues of PSIl proteins were studied by Fourier transform infrared (FTIR) spectroscopy. It was found that the binding of PG to PSIl particle induces changes in the conformation and micropolarity of phenol ring in the tyrosine residues. In other words, the PG effect on the PSIl results in blue shift of the stretch vibrational band in the phenol ring from 1620 to 1500 cm-1 with the enhancement of the absorb-ance intensity. Additionally, a new spectrum of hydrogen bond was also observed. The results imply that the hydrogen-bond formation between the OH group of phenol and one of PG might cause changes in the structures of tyrosine residues in PSIl proteins.     

Biogeographic diversification in Nolana （Solanaceae）, a ubiquitous member of the Atacama and Peruvian Deserts along the western coast of South America

The present paper reconstructs the biogeographic diversification for Nolana L.f. （Solanaceae）, a genus of 89 endemic species largely restricted to fog-dependent desert lomas formations of coastal Peru and Chile. Previous efforts have reconstructed a phylogenetic estimate for Nolana using a combination of molecular markers. Herein, we expand on those results to examine hypotheses of biogeographic origins and diversification patterns. Nolana occupies habitats within a continuous coastal desert and forms a terrestrial archipelago of discrete ＂islands＂ unique in size, topography, and species composition. Each locality contains at least one Nolana species and many contain multiple species in sympatry. The genus has a Chilean origin, with the basal clades confined to Chile with wide geographic and ecological distributions. Peru contains two strongly supported clades, suggesting two introductions with subsequent radiation. A Chilean clade of shrubby, small-flowered species appears to have had its origins from the same ancestors of the second line that radiated in Peru and northern Chile. Nolana galapagensis is endemic to the Islas Galapagos, with origins traced to Peruvian taxa with a divergence time of 0.35 mya. Rates of diversification over the past 4.02 mya in Nolana, in one of the driest habitats on Earth, suggest rapid adaptive radiation in several clades. Success in Nolana may be attributed to characters that confer a competitive advantage in unpredictable and water-dependent environments, such as succulent leaf anatomy and ecophysiology, and the reproductive mericarp unique to Nolana. The processes affecting or shaping the biota of western South America are discussed.