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1.
Last summer we officially launched the Journal of Ethnobiology and Ethnomedicine, published by BioMedCentral, with the aim of establishing a serious, peer-reviewed, open-access online journal that focuses on the multidisciplinary, interdisciplinary, and transdisciplinary fields of ethnobiology and ethnomedicine, drawing on approaches and methods from both the social and biological sciences. The strong start vindicates the widely held belief that the journal responds to a real need within the research community. The success of the journal has been most gratifying. The steady influx of submissions of high scientific standards illustrates the strong demand for a dynamic, proactive, and open-minded scientific journal in these research areas. Our aim has been to dedicate JEE to the "scientific communities" worldwide, particularly those in the developing countries.  相似文献   

2.
Amyloids are highly ordered aggregates of protein fibrils exhibiting cross-β structure formed by intermolecular hydrogen bonds. Pathological amyloid deposition is associated with the development of several socially significant incurable human diseases. Of particular interest are infectious amyloids, or prions, that cause several lethal neurodegenerative diseases in humans and can be transmitted from one organism to another. Because of almost complete absence of criteria for infectious and non-infectious amyloids, there is a lack of consensus, especially, in the definition of similarities and differences between prions and non-infectious amyloids. In this review, we formulated contemporary molecular-biological criteria for identification of prions and non-infectious amyloids and focused on explaining the differences between these two types of molecules.  相似文献   

3.
4.
Education is one of the multiple services that ecosystems and landscapes provide to societies. Despite its importance to formal and informal learning and nature-based, cognitive tourism, it is hardly taken into account in the various quantification approaches of ecosystem services. The article provides an overview of landscape educational values and the educational ecosystem service. Here, the forms of the use of landscape educational values have been summarised and the indicators for the quantification of the educational ecosystem service proposed in the literature reviewed. The criteria for the evaluation of the educational values of landscape were acquired from the literature and discussed. In order to obtain more practical viewpoints on those criteria, an exploratory survey with young experts (n = 37) from two universities of environmental sciences was conducted. Within this step, the expert method for the evaluation of the educational values of landscapes was applied. However, the results show an extremely high level of subjectivity and dependence on personal experience regarding outdoor environmental education. Nonetheless, the article can contribute to acquiring knowledge in cultural ecosystem service assessment and the application of this concept, especially in terms of the criteria and indicators which can be potentially used for the assessments.  相似文献   

5.
Water pollution control is presently one of the major thrust areas of scientific research. While coloured organic compounds generally impart only a minor fraction of the organic load to wastewaters, their colour renders them aesthetically unacceptable. Stringent regulating measures are coaxing industries to treat their waste effluents to increasingly high standards. Colour removal, in particular, has recently become an area of major scientific interest as indicated by the multitude of related research reports. During the past two decades, several decolourization techniques have been reported, few of which have been accepted by some industries. There is a need to find alternative treatments that are effective in removing dyes and colourants from large volume of effluents, which are cost-effective, like the biological or integrated systems. This article reviews some of the widely used and most promising industrial wastewater decolourization methods. Data on decolourizing efficiencies of different causative agents, obtained by means of different physical, chemical and biological methods are discussed. Further a critical review is made on the various treatment methodologies and emerging technologies with a note on their advantages and disadvantages.  相似文献   

6.
《Trends in plant science》1999,4(11):439-445
Protein lipid modification, once thought to act as a stable membrane anchor for soluble proteins, is now attracting more widespread attention for its emerging role in diverse signaling pathways and regulatory mechanisms. Most multicellular organisms have recruited specific types of lipids and a suite of unique enzymes to catalyze the modification of a select number of proteins, many of which are evolutionarily conserved in plants, animals and fungi. Each of the three known types of lipid modification – palmitoylation, myristylation and prenylation – allows cells to target proteins to the plasma membrane, as well as to other subcellular compartments. Among the lipid modifications, protein prenylation might also function as a relay between cytoplasmic isoprene biosynthesis and regulatory pathways that control cell cycle and growth. Molecular and genetic studies of an Arabidopsis mutant that lacks farnesyl transferase suggest that the enzyme has a role in abscisic acid signaling during seed germination and in the stomata. It is becoming clear that lipid modifications are not just fat for the protein, but part of a highly conserved intricate network that plays a role in coordinating complex cellular functions.  相似文献   

7.
The present checklist of ants (Hymenoptera: Formicidae) of Ambon is the first comprehensive overview of ant species recorded on the island during the last 150 years. The species list is based on literature and museum collections’ records combined with data from our field survey in 2010. In total, there are 74 ant species and subspecies representing 34 genera and six subfamilies known from Ambon. Five of the species found in undisturbed forest were exotic and indicate the overall habitat degradation on the island. The largest proportion of Ambon ant fauna are species with affinities to the Oriental region and species of Oriental-Austro-Melanesian origin. At least 20% of the species are regional endemics. In comparison to other islands in the region, the Ambon fauna seems more diverse and better sampled; however it is clear that a large part of it still remains to be described.  相似文献   

8.
Abstract

The formation of complex species in the dimethyltin(IV) and trimethyltin(IV)-carboxymethyl-L-cysteinate (carbocysteinate) systems in NaClaq, at different ionic strengths, and in a multicomponent Na+, K+, Ca2+ ,Mg2+, Cl? and SO42-? medium representative of the seawater major composition, is discussed. Experimental results give evidence for the formation of the following species (L = carbocysteinate): [(CH3)2Sn(L)]0, [(CH3)2Sn(HL)]+, [(CH3)2Sn(OH)(L)]?, [(CH3)2Sn(OH)2(L)]2? in the DMT–CCYS system, and [(CH3)3Sn(HL)]0, [(CH3)3Sn(L)]? and [(CH3)3Sn(OH)(L)]2? in the TMT-CCYS system. The ionic strength dependence of formation constants was taken into account by an extended Debye Hückel type equation and by the SIT (Specific ion Interaction Theory). Measurements were carried out also on the dimethyltin(IV)-glutamate and trimethyltin(IV)-glutamate systems in NaClaq, owing the strict similarity of glutamate and carbocysteinate. Results obtained show the formation of complex species having the same stoichiometry as those formed in the DMT- and TMT-carbocysteinate systems, with very similar stability, confirming that carbocysteinate behaves as a dicarboxylic amino acid without involving the sulfur-bridge potential binding site in metal coordination.  相似文献   

9.
Skin represents the largest organ of the human body and plays a crucial role in its protection from the negative impact of the outside environment, maintains its homeostasis, enables sensory interaction and thermoregulation. The traumatized skin tissue undergoes several phenotype switches due to progressive reoxygenation and release of cytokine and growth factors, that activate mechanisms of reparative processes. However, in case of wounds colonized with pathogenic microflora natural regenerative mechanisms become substantially impaired, that could lead to chronic inflammatory states with non-healing skin lesions. Herein, we present the initial results of our studies aimed at the design of bifunctional peptide-based compounds. The chemical approach, that was utilized in this work, was based on the conjugation of antimicrobial peptides with the peptides, that have potential pro-proliferative and/or cytoprotective activity towards human keratinocytes and fibroblasts, in order to obtain antimicrobials with reduced cytotoxicity or compounds that maintain both activities, i.e. inhibit bacterial or fungi growth and activate cell proliferation/migration in in vitro tests. As a result, we obtained a group of peptide conjugates that effectively inhibited the growth of selected bacterial and fungi strains and were able to stimulate proliferation and migration of keratinocytes and fibroblasts under their effective microbicidal concentrations.  相似文献   

10.
The regional malaria epidemics of the early 1900s provided the basis for much of our current understanding of malaria epidemiology. Colonel Gill, an eminent malariologist of that time, suggested that the explosive nature of the regional epidemics was due to a sudden increased infectiousness of the adult population. His pertinent observations underlying this suggestion have, however, gone unheeded. Here, the literature on Plasmodium seasonal behaviour is reviewed and three historical data sets, concerning seasonal transmission of Plasmodium falciparum, are examined. It is proposed that the dramatic seasonal increase in the density of uninfected mosquito bites results in an increased infectiousness of the human reservoir of infection and, therefore, plays a key role in "kick-starting" malaria parasite transmission.  相似文献   

11.
Abstract  Interactions between plants and animals are analyzed starting from the advantages gained by animals and proceeding to those gained exclusively by plants. These interactions are essentially of five types: 1. predation of plants by animals; 2. benevolence of plants towards certain animals to prevent or reduce predation; 3. predation by plants (carnivorous plants); 4. symbiosis and mutualism; 5. seduction and deception of animals by plants for dispersal of plant reproductive structures. All types of plants are preyed on by animals, though from as far back in evolution as algae, certain plant molecules reduce or prevent predation. In the most primitive land plants, other types of interactions beneficial for plants are encountered. More evolved land plants (angiosperms) show all facets of the five types of interaction, whereas in prokaryotic and eukaryotic algae there is only predation and in some cases countermeasures to avoid it. An evolutionary path leading from predation, the original condition, to seduction, deception and carnivory, is also postulated. Keywords Plants, Animals, Predation, Benevolence, Symbiosis, Mutualism, Pollination, Seed dispersal Subject codes: Animal Ecology, Plant Ecology, Evolutionary Biology  相似文献   

12.
Fas/Fas ligand (FasL) system is one of the key apoptotic signaling entities in the extrinsic apoptotic pathway. De-regulation of this pathway, i.e. by mutations may prevent the immune system from the removal of newly-formed tumor cells, and thus lead to tumor formation. The present study investigated the association between −1377 G/A (rs2234767) and −670 A/G (rs1800682) polymorphisms in Fas as well as single nucleotide polymorphisms INV2nt −124 A/G (rs5030772) and −844 C/T (rs763110) in FasL in a sample of Iranian patients with breast cancer. This case-control study was done on 134 breast cancer patients and 152 normal women. Genomic DNA was extracted from whole blood samples. The polymorphisms were determined by using tetra-ARMS-PCR method. There was no significant difference in the genotype distribution of FAS rs2234767 polymorphism between cases and controls. FAS rs1800682, FASL rs5030772, and FASL rs763110 genotypes showed significant associations with an increasing risk of breast cancer (odds ratio OR = 3.18, P = 0.019; OR = 5.08, P = 0.012; OR = 2.40, P = 0.024, respectively). In conclusion, FAS rs2234767 was not associated with breast cancer risk. Though, FAS rs1800682, FASL rs5030772, and FASL rs763110 polymorphisms were associated with the risk of breast cancer in the examined population.  相似文献   

13.
During the past decade, there have been many optimistic claims concerning the potential of novel oil-based products from genetically engineered crops, particularly for the manufacture of a new generation of renewable, carbon-neutral, industrial materials. Such claims have been underpinned by an impressive series of scientific advances that have resulted in the isolation of genes encoding most of the enzymes directly involved in oil biosynthesis. In some cases, these enzymes have even been re-engineered by site-directed or random mutagenesis to allow production of new fatty acid profiles that are not present in any existing organism. This has opened up the prospect of engineering `designer oil crops' to produce novel fatty acids with chain lengths from C8 to C24 and with a wide range of industrially useful functionalities, including hydroxylation, epoxidation, and conjugated and non-conjugated double or triple bonds. However, there remain significant technical challenges before this promise of designer transgenic crops is likely to be translated into large-scale commercial reality. For example, it has proved surprisingly difficult to engineer high levels of novel fatty acids in genetically engineered transgenic plants, although many wild type seeds can readily accumulate 90–95% of a single fatty acid in their storage oil. Another complication is the recent discovery of multiple pathways of triacylglycerol biosynthesis and the difficulty in ensuring that novel fatty acids are only channelled towards storage triacylglycerols and not to membrane or signalling lipids in major target crops like rapeseed. New findings from our lab have suggested that there may also be problems with the tissue specificity of some of the `seed-specific' gene promoters that are commonly used in transgenic crops. There are also considerable and often underestimated challenges associated with the economics, management and public acceptability of all transgenic crops, even for non-food use. In most cases the projections of petroleum reserves over the next few decades make it unlikely that crop-derived commodity products that substitute for petroleum will be competitive. Also the scale of crop production required to generate millions of tonnes of commodity oils, e.g., for biodegradable plastics, is likely to seriously impinge on food production at a time of increasing global populations, and is therefore unlikely to be acceptable. An alternative strategy to transgenic oil crops is to use molecular breeding techniques in order to develop new crops that already synthesise high levels of novel fatty acids of interest. Finally, the most promising market sectors and product ranges for the future development of oil crop biotechnology will be discussed.  相似文献   

14.

Background  

High-throughput genotyping and phenotyping projects of large epidemiological study populations require sophisticated laboratory information management systems. Most epidemiological studies include subject-related personal information, which needs to be handled with care by following data privacy protection guidelines. In addition, genotyping core facilities handling cooperative projects require a straightforward solution to monitor the status and financial resources of the different projects.  相似文献   

15.
Wolstenholme J  Angell RR 《Chromosoma》2000,109(7):435-438
The mechanism of trisomy formation and its relationship to increased maternal age is not understood. Molecular analysis of the pattern of inheritance of DNA markers in trisomy families shows trisomies can be grouped according to whether the affected chromosomes inherited from their mothers are heterozygous or homozygous with respect to the centromeres. Furthermore, molecular analysis reveals that those that are heterozygous have fewer chiasmata, which are located more distally, while those that are homozygous have more chiasmata proximally located. Cytogenetic analysis of human oocytes shows that the kind of imbalance predicted by the classic hypothesis of nondisjunction, i.e. extra whole chromosomes at the second metaphase, is rarely found, whereas the common expression of imbalance is seen as single chromatids. We hypothesise that one mechanism links these data: the mechanism depends on the prediction from the cytogenetic data that cohesion within the bivalent complex is severely weakened during the extended dictyate stage in older women. Consequently, when meiosis resumes, at the time of ovulation, the bivalent emerges as four chromatids held together only by its chiasmata. In accordance with the rules of orientation on the spindle, the final balanced shape of the configuration achieved at metaphase I, in this case determined by the position of the chiasmata, will dictate whether the subsequent segregation of the chromatids will result in their heterozygosity or homozygosity. It follows that the concept of "first division" and "second division" errors, i.e. of nondisjunction originating at first or second meiotic division as defined by centromeric hetero- or homozygosity, may be erroneous.  相似文献   

16.
17.
Although every organism shares some common features of replication, this process varies greatly among eukaryotic species. Current data show that mathematical models of the organization of origins based on possibility theory may be applied (and remain accurate) in every model organism i.e. from yeast to humans. The major differences lie within the dynamics of origin firing and the regulation mechanisms that have evolved to meet new challenges throughout the evolution of the organism. This article elaborates on the relations between chromatin structure, organization of origins, their firing times and the impact that these features can have on genome stability, showing both differences and parallels inside the eukaryotic domain.  相似文献   

18.
 Contrary to traditional views, molecular evidence indicates that the protostomian ventral nerve cord plus apical brain is homologous with the vertebrates’ dorsal spinal cord plus brain. The origin of the protostomian central nervous system from a larval apical organ plus longitudinal areas along the fused blastopore lips has been documented in many species. The origin of the chordate central nervous system is more enigmatic. About a century ago, Garstang proposed that the ciliary band of a dipleurula-type larva resembling an echinoderm larva should have moved dorsally and fused to form the neural tube of the ancestral chordate. This idea is in contrast to a number of morphological observations, and it is here proposed that the neural tube evolved through lateral fusion of a ventral, postoral loop of the ciliary band in a dipleurula larva; the stomodaeum should move from the ventral side via the anterior end to the dorsal side, which faces the substratum in cephalo- chordates and vertebrates. This is in accordance with the embryological observations and with the molecular data on the dorsoventral orientation. The molecular observations further indicate that the anterior part of the insect brain is homologous with the anterior parts of the vertebrate brain. This leads to the hypothesis that the two organs evolved from the same area in the latest common bilaterian ancestor, just anterior to the blastopore, with the protostome brain developing from the anterior rim of the blastopore (i.e. in front of the protostome mouth) and the chordate brain from an area in front of the blastopore, but behind the mouth (i.e. behind the deuterostome mouth). Received: 28 August 1998 / Accepted: 14 November 1998  相似文献   

19.
The properties and geometry of bone in the mandible play a key role in mandible behaviour during a person’s lifetime, and attention needs to be paid to the influence of bone properties. We analysed the effect of bone geometry, size and bone properties in mandible behaviour, experimenting on cadaveric mandibles and FE models. The study was developed using the geometry of a cadaveric mandible without teeth. Three models of cadaveric condyles were experimentally tested with instrumented with four rosettes, and a condyle reaction of 300 N. Four finite element models were considered to validate the experiments and analyse mandible behaviour. One numeric model was simulated with 10 muscles in a quasi-static condition. The experimental results present different condyle stiffness’s, of 448, 215 and 254 N/mm. The values presented in the rosettes are influenced by bone geometry and bone thickness; maximum value was ?600 με in rosette #4, and the maximum strain difference between mandibles was 111%. The numerical results show that bone density decreases and strain distribution increases in the thinner mandible regions. Nevertheless, the global behaviour of the structure remains similar, but presents different strain magnitudes. The study shows the need to take into account bone characteristics and their evolutions in order to improve implant design and fixation throughout the patient life. The change in bone stiffness promotes a change in maximum strain distribution with same global behaviour.  相似文献   

20.
Pettersson  Kurt  Grust  Karin  Weyhenmeyer  Gesa  Blenckner  Thorsten 《Hydrobiologia》2003,501(1-3):75-81
The effect of submerged macrophytes on interactions among epilimnetic phosphorus, phytoplankton, and heterotrophic bacterioplankton has been acknowledged, but remains poorly understood. Here, we test the hypotheses that the mean summer phytoplankton biomass (chlorophyll a): phosphorus ratios decrease with increased macrophyte cover in a series of nine lakes. Further, we test that both planktonic respiration and bacterioplankton production increase with respect to phytoplankton biomass along the same gradient of increasing macrophyte cover. Increased macrophyte cover was associated with a lower fraction of particulate phosphorus in epilimnia, with total particulate phosphorus declining from over 80% of total phosphorus in a macrophyte free lake to less than 50% in a macrophyte rich lake. Phytoplankton biomass (chlorophyll a) too was lower in macrophyte dominated lakes, despite relatively high levels of total dissolved phosphorus. Planktonic respiration and bacterioplankton production were higher in macrophyte rich lakes than would be expected from phytoplankton biomass alone, pointing to a subsidy of bacterioplankton metabolism by macrophyte beds at the whole lake scale. The results suggest that the classical view of pelagic interactions, which proposes phosphorus determines phytoplankton abundance, which in turn determines bacterial abundance through the production of organic carbon, becomes less relevant as macrophyte cover increases.  相似文献   

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