Deploying large numbers of mobile robots which can interact with each other produces swarm intelligent behavior. However, mobile robots are normally running with finite energy resource, supplied from finite battery. The limitation of energy resource required human intervention for recharging the batteries. The sharing information among the mobile robots would be one of the potentials to overcome the limitation on previously recharging system. A new approach is proposed based on integrated intelligent system inspired by foraging of honeybees applied to multimobile robot scenario. This integrated approach caters for both working and foraging stages for known/unknown power station locations. Swarm mobile robot inspired by honeybee is simulated to explore and identify the power station for battery recharging. The mobile robots will share the location information of the power station with each other. The result showed that mobile robots consume less energy and less time when they are cooperating with each other for foraging process. The optimizing of foraging behavior would result in the mobile robots spending more time to do real work.
The south-east Asian genus Eupoa is redescribed and diagnosed. Seven new species are diagnosed, described and illustrated: E. daklak sp. n. (♀) from Viet-Nam; E. lehtineni sp. n. (♂♀) from India, Thailand and Viet-Nam; E. lobli sp. n. (♂) from Malaysia; E. pappi sp. n. (♂) from Thailand; E. pulchella sp. n.(♂) from Thailand; E. schwendingeri sp. n. (♂♀) from Thailand; and E. thailandica sp. n. (♂♀) from Thailand. Eupoa prima Żabka, 1985 and E. yunnanensis Peng & Kim, 1997 are redescribed and illustrated on the basis of type and/or newly collected materials. The female of E. yunnanensis Peng & Kim, 1997 is found and described for the first time.
Miyagiella Harbach, subgen. nov., is introduced as a new subgenus of Topomyia Leicester for a remarkable male mosquito, Topomyia discors Harbach, sp. nov., from Sabah, Malaysia. A diagnosis of the subgenus is provided that features unique anatomical characters of the genitalia of the holotype male. Miyagiella is very distinct from the two previously recognised subgenera of Topomyia, but is perhaps more closely related to the nominotypical subgenus than to subgenus Suaymyia Thurman. Salient differences that distinguish the three subgenera are contrasted; the holotype male of To. discors is described and its unique genitalia are illustrated.
Predator-prey interactions are among the main ecological interactions that shape the diversity of biological form. In many cases, the evolution of the mollusc shell form is presumably driven by predation. However, the adaptive significance of several uncommon, yet striking, shell traits of land snails are still poorly known. These include the distorted coiled "tuba" and the protruded radial ribs that can be found in micro-landsnails of the genus Plectostoma. Here, we experimentally tested whether these shell traits may act as defensive adaptations against predators. We characterised and quantified the possible anti-predation behaviour and shell traits of Plectostoma snails both in terms of their properties and efficiencies in defending against the Atopos slug predatory strategies, namely, shell-apertural entry and shell-drilling. The results showed that Atopos slugs would first attack the snail by shell-apertural entry, and, should this fail, shift to the energetically more costly shell-drilling strategy. We found that the shell tuba of Plectostoma snails is an effective defensive trait against shell-apertural entry attack. None of the snail traits, such as resting behaviour, shell thickness, shell tuba shape, shell rib density and intensity can fully protect the snail from the slug's shell-drilling attack. However, these traits could increase the predation costs to the slug. Further analysis on the shell traits revealed that the lack of effectiveness in these anti-predation shell traits may be caused by a functional trade-off between shell traits under selection of two different predatory strategies.
Probiotic microorganisms have been documented over the past two decades to play a role in cholesterol-lowering properties via various clinical trials. Several mechanisms have also been proposed and the ability of these microorganisms to deconjugate bile via production of bile salt hydrolase (BSH) has been widely associated with their cholesterol lowering potentials in prevention of hypercholesterolemia. Deconjugated bile salts are more hydrophobic than their conjugated counterparts, thus are less reabsorbed through the intestines resulting in higher excretion into the feces. Replacement of new bile salts from cholesterol as a precursor subsequently leads to decreased serum cholesterol levels. However, some controversies have risen attributed to the activities of deconjugated bile acids that repress the synthesis of bile acids from cholesterol. Deconjugated bile acids have higher binding affinity towards some orphan nuclear receptors namely the farsenoid X receptor (FXR), leading to a suppressed transcription of the enzyme cholesterol 7-alpha hydroxylase (7AH), which is responsible in bile acid synthesis from cholesterol. This notion was further corroborated by our current docking data, which indicated that deconjugated bile acids have higher propensities to bind with the FXR receptor as compared to conjugated bile acids. Bile acids-activated FXR also induces transcription of the IBABP gene, leading to enhanced recycling of bile acids from the intestine back to the liver, which subsequently reduces the need for new bile formation from cholesterol. Possible detrimental effects due to increased deconjugation of bile salts such as malabsorption of lipids, colon carcinogenesis, gallstones formation and altered gut microbial populations, which contribute to other varying gut diseases, were also included in this review. Our current findings and review substantiate the need to look beyond BSH deconjugation as a single factor/mechanism in strain selection for hypercholesterolemia, and/or as a sole mean to justify a cholesterol-lowering property of probiotic strains.
Epilepsy is one of the most common chronic disorders affecting individuals of all ages. A greater understanding of pathogenesis in epilepsy will likely provide the basis fundamental for development of new antiepileptic therapies that aim to prevent the epileptogenesis process or modify the progression of epilepsy in addition to treatment of epilepsy symptomatically. Therefore, several investigations have embarked on advancing knowledge of the mechanism underlying epileptogenesis, understanding in mechanism of pharmacoresistance and discovering antiepileptogenic or disease-modifying therapy. Animal models play a crucial and significant role in providing additional insight into mechanism of epileptogenesis. With the help of these models, epileptogenesis process has been demonstrated to be involved in various molecular and biological pathways or processes. Hence, this article will discuss the known and postulated mechanisms of epileptogenesis and challenges in using the animal models.
Eleven taxa including one new species of gammaridean amphipods are reported from the waters of Pulau Tioman. The presence of Tethygeneia sunda sp. n. represents the first record of the genus from the South China Sea. Additional material of Ampelisca brevicornis (Costa, 1853); Cymadusa vadosa Imbach, 1967; Paradexamine setigera Hirayama, 1984; Ericthonius pugnax (Dana, 1853); Leucothoe furina (Savigny, 1816); Microlysias xenokeras (Stebbing, 1918); Monoculodes muwoni Jo, 1990 are identified from the South China Sea, supporting previous records by Lowry (2000), Huang (1994), Imbach (1967), Margulis (1968) and Nagata (1959). Three additional species, Gitanopsis pusilla K.H. Barnard, 1916, Liljeborgia japonica Nagata, 1965b and Latigammaropsis atlantica (Stebbing, 1888), whilst previously reported from the neighbouring waters, comprise new records for the South China Sea.
Tetrasticta gnatha sp. n., collected under the bark of a rotten fallen tree in Peninsular Malaysia, is described. A habitus photograph, line drawings of diagnostic characters, and a diagnosis are provided. The new species is readily distinguished from all known congeners by having long mandibles, and long, curved maxillary palpi.
Animal inflicted wounds, left untreated may result in chronic bacterial or fungal infection. Clinical features of these infections may overlap leading to a delay in diagnosis and treatment. We report a case of chronic non-healing cat bite wound treated with several antibiotics without improvement. Later patient developed the classical "sporotrichoid spread" and a presumptive diagnosis of sporotrichosis was made. Laboratory investigation for fungal culture and skin biopsy failed to identify the underlying pathogen. A trial of oral antifungal agent resulted in complete recovery of the lesions implicating fungus as the causative pathogen. Physicians should have a high index of suspicion for fungal infections when managing animal inflicted wounds.
Trophic organisation defines the flow of energy through ecosystems and is a key component of community structure. Widespread and intensifying anthropogenic disturbance threatens to disrupt trophic organisation by altering species composition and relative abundances and by driving shifts in the trophic ecology of species that persist in disturbed ecosystems. We examined how intensive disturbance caused by selective logging affects trophic organisation in the biodiversity hotspot of Sabah, Borneo. Using stable nitrogen isotopes, we quantified the positions in the food web of 159 leaf-litter ant species in unlogged and logged rainforest and tested four predictions: (i) there is a negative relationship between the trophic position of a species in unlogged forest and its change in abundance following logging, (ii) the trophic positions of species are altered by logging, (iii) disturbance alters the frequency distribution of trophic positions within the ant assemblage, and (iv) disturbance reduces food chain length. We found that ant abundance was 30% lower in logged forest than in unlogged forest but changes in abundance of individual species were not related to trophic position, providing no support for prediction (i). However, trophic positions of individual species were significantly higher in logged forest, supporting prediction (ii). Consequently, the frequency distribution of trophic positions differed significantly between unlogged and logged forest, supporting prediction (iii), and food chains were 0.2 trophic levels longer in logged forest, the opposite of prediction (iv). Our results demonstrate that disturbance can alter trophic organisation even without trophically-biased changes in community composition. Nonetheless, the absence of any reduction in food chain length in logged forest suggests that species-rich arthropod food webs do not experience trophic downgrading or a related collapse in trophic organisation despite the disturbance caused by logging. These food webs appear able to bend without breaking in the face of some forms of anthropogenic disturbance.
Population surveys and species recognition for roosting bats are either based on capture, sight or optical-mechanical count methods. However, these methods are intrusive, are tedious and, at best, provide only statistical estimations. Here, we demonstrated the successful use of a terrestrial Light Detection and Ranging (LIDAR) laser scanner for remotely identifying and determining the exact population of roosting bats in caves. LIDAR accurately captured the 3D features of the roosting bats and their spatial distribution patterns in minimal light. The high-resolution model of the cave enabled an exact count of the visibly differentiated Hipposideros larvatus and their roosting pattern within the 3D topology of the cave. We anticipate that the development of LIDAR will open up new research possibilities by allowing researchers to study roosting behaviour within the topographical context of a cave's internal surface, thus facilitating rigorous quantitative characterisations of cave roosting behaviour.
Tropical beta diversity, and particularly that of herbivorous insects in rainforests, is often considered to be enormous, but this notion has recently been challenged. Because tropical beta diversity is highly relevant to our view on biodiversity, it is important to gain more insights and to resolve methodological problems that may lead to contradictions in different studies. We used data on two ecologically distinct moth families from Southeast Asia and analyzed separately the contribution of beta components to overall species richness at three spatial scales. Observed diversity partitions were compared under different types of null models. We found that alpha diversity was lower than expected on the basis of null models, whereas hierarchical beta components were larger than expected. Beta components played a significant role in shaping gamma diversity, and their contribution can be high (multiplicative beta >5). We found a reduction in beta components when comparing primary forests to agricultural sites (cf. "biotic homogenization"), but even in these habitats, beta components were still substantial. Our analyses show that beta components do play an important role in our data on tropical herbivorous insects and that these results are not attributable to lumping different habitats when sampling environmental gradients.
Asopines are predators of insects, with several species with potential as biocontrol agents of a number of pests. Metrogaleruca obscura (Degeer), a neotropical species of Galerucini, was introduced in Malaysia, Asia, and Mauritius, Africa, to control the spread of Cordia curassavica (Boraginaceae), a native plant of the neotropics. The occurrence of Podisus nigrispinus (Dallas) preying on M. obscura is recorded, and Cordia verbenacea (Boraginaceae) is mentioned as a host plant for M. obscura. A list of Chrysomelidae attacked by asopines in the neotropical region is also presented.
Two new species of urothoid amphipods from Pulau Sibu and Pulau Tinggi, Johor are described and illustrated. The specimens of Urothoe sibuensis new species were collected by vertical haul plankton net and is distinctively different from other existing Urothoe species by these combination of special characters; similar gnathopods 1-2 with short and stout propodus expanded into poorly defined palms; large eyes and epimeron 3 smooth. Urothoe tinggiensis new species as collected using an airlift suction sampler at seagrass area is characterized by its different gnathopodal configuration with setose dactylus of 5th pereopod; eyes minute; carpus is wider than merus in the 5th pereopod; subquadrate coxa 4; merus and carpus of pereopods 6-7 are linear.
Since the discovery of the double-helical structure of DNA, genetic regulation of gene expression has been well elucidated. More recently, another equally, if not more, important scheme of regulation of gene expression, called epigenetics, has emerged to explain the many biological observations that traditional genetic mechanisms have failed to decipher. Epigenetics is a discipline of study on the biological consequences of cellular alterations that do not involve nucleotide changes, as opposed to genetic mutations. Epigenetic changes are reversible and may lead to loss or gain of biological functions. The three most reported mechanisms of epigenetic regulation of gene expression involve changes in: (i) chromatin remodelling, (ii) DNA methylation and (iii) microRNA (miRNA). More importantly, many of the elucidated epigenetic changes are linked to the pathogenesis of human diseases and cancers. In this mini review, core concepts and basic experimental approaches in the study of epigenetic regulation of gene expression are briefly reviewed in relation to disease, with emphasis on cancer. This mini review also intends to highlight the fact that, besides genetics, epigenetics is now a discipline physicians and clinical research scientists can no longer ignore in their pursuit to understand disease and cancer and to develop new therapeutic strategies for treatment.
The purpose of this study is to determine whether isolated suspension mouse peripheral mononucleated blood cells have the potential to differentiate into two distinct types of cells, i.e., osteoblasts and osteoclasts.