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71.
72.
Ant colony optimisation (ACO) for classification has mostly been limited to rule-based approaches where artificial ants walk on datasets in order to extract rules from the trends in the data, and hybrid approaches which attempt to boost the performance of existing classifiers through guided feature reductions or parameter optimisations. A recent notable example that is distinct from the mainstream approaches is PolyACO, which is a proof-of-concept polygon-based classifier that resorts to ACO as a technique to create multi-edged polygons as class separators. Despite possessing some promise, PolyACO has some significant limitations, most notably, the fact of supporting classification of only two classes, including two features per class. This paper introduces PolyACO+, which is an extension of PolyACO in three significant ways: (1) PolyACO+ supports classifying multiple classes, (2) PolyACO+ supports polygons in multiple dimensions enabling classification with more than two features, and (3) PolyACO+ substantially reduces the training time compared to PolyACO by using the concept of multi-levelling. This paper empirically demonstrates that these updates improve the algorithm to such a degree that it becomes comparable to state-of-the-art techniques such as SVM, neural networks, and AntMiner+.  相似文献   
73.
An efficient and rapid tissue culture system employing shoot tip explants has been developed for Eclipta alba (L) Hassk, an important medicinal plant of the family Asteraceae. The highest shoot regeneration frequency (95%) as well as the maximum number (32.2 ± 0.4) of shoots was recorded on MS medium amended with BA (5 μM) and NAA (0.5 μM). The regenerated shoots rooted best on MS medium supplemented with 0.2 μM IBA. The in vitro developed plantlets were acclimatized successfully with 100 % survival.  相似文献   
74.
In Vitro Cellular & Developmental Biology - Plant - An in vitro regeneration system for propagation of a valuable medicinal tree, Pterocarpus marsupium, using shoot tip (ST) explants derived...  相似文献   
75.
DNA methylation is essential in mammalian development. We have hypothesized that methylation differences induced by trisomy 21 (T21) contribute to the phenotypic characteristics and heterogeneity in Down syndrome (DS). In order to determine the methylation differences in T21 without interference of the interindividual genomic variation, we have used fetal skin fibroblasts from monozygotic (MZ) twins discordant for T21. We also used skin fibroblasts from MZ twins concordant for T21, normal MZ twins without T21, and unrelated normal and T21 individuals. Reduced Representation Bisulfite Sequencing (RRBS) revealed 35 differentially methylated promoter regions (DMRs) (Absolute methylation differences = 25%, FDR < 0.001) in MZ twins discordant for T21 that have also been observed in comparison between unrelated normal and T21 individuals. The identified DMRs are enriched for genes involved in embryonic organ morphogenesis (FDR = 1.60 e -03) and include genes of the HOXB and HOXD clusters. These DMRs are maintained in iPS cells generated from this twin pair and are correlated with the gene expression changes. We have also observed an increase in DNA methylation level in the T21 methylome compared to the normal euploid methylome. This observation is concordant with the up regulation of DNA methyltransferase enzymes (DNMT3B and DNMT3L) and down regulation of DNA demethylation enzymes (TET2 and TET3) observed in the iPSC of the T21 versus normal twin. Altogether, the results of this study highlight the epigenetic effects of the extra chromosome 21 in T21 on loci outside of this chromosome that are relevant to DS associated phenotypes.  相似文献   
76.
Myrtus communis is a typical plant of the Mediterranean area, which is mainly used as animal and human food and, in folk medicine, for treating some disorders. In the present study, we evaluated in vitro antibacterial and antifungal properties of the essential oils of Myrtus communis (McEO), as well as its phytochemical composition. The GC/MS analysis of the essential oil revealed 17 compounds. Myrtenyl acetate (20.75%), 1,8‐cineol (16.55%), α‐pinene (15.59%), linalool (13.30%), limonene (8.94%), linalyl acetate (3.67%), geranyl acetate (2.99%), and α‐terpineol (2.88%) were the major components. The antimicrobial activity of the essential oil was also investigated on several microorganisms. The inhibition zones and minimal inhibitory concentration (MIC) values of bacterial strains were in the range of 16–28 mm and 0.078–2.5 mg/ml, respectively. The inhibitory activity of the McEO against Gram‐positive bacteria was significantly higher than against Gram‐negative. It also exhibited remarkable activity against several fungal strains. The investigation of the mode of action of the McEO by the time‐kill curve against Listeria monocytogenes (food isolate) showed a drastic bactericidal effect after 5 min using a concentration of 312 μg/ml. These results evidence that the McEO possesses antimicrobial properties, and it is, therefore, a potential source for active ingredients for food and pharmaceutical industries.  相似文献   
77.
Abstract

In the present study, an alternate method for germplasm storage in the form of artificial seeds was standardized via nodal explants excised from in vitro proliferated shoots. The explants were encapsulated using sodium alginate and calcium chloride as gelling matrix. For development of root along with shoot, excised nodal segments were pretreated with ½ MS medium along with 20 μM IBA for 24 h and encapsulation was carried thereafter. Combination of 3% sodium alginate augmented with 100 mM CaCl2.2H2O was found appropriate for the formation of clear and uniform beads and subsequent conversion of encapsulated nodal segments into plantlets. Maximum (66%) encapsulated nodal segments were converted into plantlets on MS medium supplemented with 7.5 μM BA and 0.5 μM NAA after eight weeks. Regeneration frequency of auxin-pretreated encapsulated and non-encapsulated nodal segments (stored at 4 ºC) was evaluated at different storage time (0 to 6 weeks). After four weeks of storage, encapsulated propagules exhibited highest conversion response on the optimized medium after eight weeks of culture. Plantlets were hardened and established with success in ex vitro conditions. Conversion of synthetic seeds into plantlets was observed when these were directly sown in autoclaved SoilriteTM (Keltech Energies, Bangalore, India).  相似文献   
78.
Hydrobiologia - The population of horseshoe crabs, Tachypleus gigas, in Malaysian waters is declining due to overexploitation, pollution, and loss of natural habitats. As an initiative to increase...  相似文献   
79.
The objective of this study was to estimate the oxygen uptake (&OV0312;O2) in elite youth soccer players using measures of heart rate (HR) and ratings of perceived exertion (RPEs). Forty-six regional-level male youth soccer players (~13 years) participated in 2 VO(2)max tests. Data for HR, RPE, and VO(2) were simultaneously recorded during the VO(2)max tests with incremental running speed. Regression equations were derived from the first VO(2)max test. Two weeks later, all players performed the same VO(2)max test to validate the developed regression equations. There were no significant differences between the estimated values in the first test and actual values in the second test. During the continuous endurance exercise, the combination of percentage of maximal HR (%HRmax) and RPE measures gave similar estimation of %VO(2)max (R = 83%) in comparison to %HRmax alone (R = 81%). However, the estimation of VO(2) using combined %HRmax and RPE was not satisfactory (R = 45-46%). Therefore, the use of %HRmax (without RPE) to estimate %VO(2)max could be a useful tool in young soccer players during field-based continuous endurance testing and training. Specifically, coaches can use the %HRmax to quantify internal loads (%VO(2)max) and subsequently implement continuous endurance training at appropriate intensities. Furthermore, it seems that RPE is more useful as a measure of internal load during noncontinuous (e.g., intermittent and sprint) exercises but not to estimate %VO(2)max during continuous aerobic exercise (R = 59%).  相似文献   
80.
Phloem-sucking mustard aphid (Lipaphis erysimi) is a major pest of mustard (Brassica juncea). Pot experiment with randomised block design was conducted with five replicates of each of five cultivars (Alankar, Pusa Jai Kisan, Rohini, Sakha and Varuna) of the mustard for their degree of inherited resistance and/or susceptibility to the mustard aphid infestation. Forty-five days old (from date of sowing) pot-grown plants of all selected cultivars of mustard were exposed to 40 adult mustard aphids. The aphid-infested plants were kept in specially designed net houses of fine mesh to protect from predators and/or migration of aphids from one to other host. The aphid population and some growth attributes of the selected cultivars of mustard were recorded 15 and 30 days later (i.e. at 60 and 75 days after sowing). The aphid population multiplied more rapidly on Rohini than other four cultivars. Cultivar Alankar resisted most and supported to least number of aphid’s off-springs. Statistically analysed growth attributes (fresh plant mass, dry plant mass, protein, chlorophyll and carotenoid contents), resistance attribute (proline) and population demography of aphids revealed that some inherited characteristics of avoidance, antibiosis and repellence to herbivores helped cultivar Alankar to excel despite equal degree of aphid attacks as on other cultivars. Cultivar Rohini for the want of such resisting factors remained vulnerable to aphid herbivory. These two cultivars (Alankar and Rohini) form good research material for comparative studies on plant defences to herbivory and a tri- trophic resistance through volatile chemical signalling.  相似文献   
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