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Displaying publications 41 - 60 of 4445 in total

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Mutualism between tree shrews and pitcher plants: perspectives and avenues for future research

Clarke C, Moran JA, Chin L

Plant Signal Behav, 2010 Oct;5(10):1187-9.
PMID: 20861680

Three species of Nepenthes pitcher plants from Borneo engage in a mutualistic interaction with mountain tree shrews, the basis of which is the exchange of nutritional resources. The plants produce modified "toilet pitchers" that produce copious amounts of exudates, the latter serving as a food source for tree shrews. The exudates are only accessible to the tree shrews when they position their hindquarters over the pitcher orifice. Tree shrews mark valuable resources with faeces and regularly defecate into the pitchers when they visit them to feed. Faeces represent a valuable source of nitrogen for these Nepenthes species, but there are many facets of the mutualism that are yet to be investigated. These include, but are not limited to, seasonal variation in exudate production rates by the plants, behavioral ecology of visiting tree shrews, and the mechanism by which the plants signal to tree shrews that their pitchers represent a food source. Further research into this extraordinary animal-plant interaction is required to gain a better understanding of the benefits to the participating species.

Matched MeSH terms: Symbiosis/physiology*; Tupaiidae/physiology*; Sarraceniaceae/physiology*
Fulltext Microalgae associated with Leptoconops breeding sites in selected sandy beaches of Malaysia

Rohani A, Khadri MS, Lee HL

Trop Biomed, 2006 Dec;23(2):164-71.
PMID: 17322818 MyJurnal

A study was carried out to investigate correlation between presence of specific microalgal species and Leptoconops biting midge larvae in its breeding habitats. Sand samples containing microalgae were collected from the beach where the midges were most commonly biting and from sand beaches which are potential as breeding habitats of Leptoconops. The survey covered sand beaches from 12 seperate islands. At all sites, the Bacillariophyta constituted the largest representatives of the microalgae community with the majority from the Naviculaceae family. A total of 24 microalgal species were identified from the sand samples collected from the study sites. Sand samples from Kentot Kecil Island had the highest number of algal species (11.0) and the highest algae species diversity ( Shanon-Weiner Diversity Index, H' = 0.884). Besar Island (Johor) had the lowest number of algal species (2.0) whereas Tengol A Island had the lowest algae species diversity (H'=0.234). Highest similarity index was recorded between sand samples collected from Tengol A Island and Tengol B Island (75.0%) followed by Besar Island (Melaka) and Tengol B Island (62.0 %). The variation between other islands were relatively high. Virtually many kinds of algae were found where Leptoconops were breeding but Fragilaria intermedia, Mastigloia minuta and Navicula advena were particularly common.

Matched MeSH terms: Ceratopogonidae/physiology*; Reproduction/physiology; Eukaryota/physiology*
Physiological Responses of Exergaming Boxing in Adults: A Systematic Review and Meta-Analysis

Mohd Jai NA, Mat Rosly M, Abd Razak NA

Games Health J, 2021 Apr;10(2):73-82.
PMID: 33297818 DOI: 10.1089/g4h.2020.0078

Objective: Studies investigating the effects of exergaming in available platforms are still limited. This review aims to systematically identify available studies on physiological intensities of exergaming boxing in able-bodied adults and recategorize them based on different platforms or environments. The meta-analysis further analyzes the physiological responses during exergaming boxing into a set of pooled data for any evidence of outliers, heterogeneity, or publication bias. Materials and Methods: A systematic search was conducted by using databases from Google Scholar, PubMed, and Web of Science. Population, intervention, comparison, and outcomes (PICO) and preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were used in the study selection process for the review. Results: From the 1534 articles examined, 16 articles were included for further analyses. Results indicated that exergaming boxing exhibits a wide range of metabolic equivalent of task (MET) values and intensity, from very light to vigorous, with elements of heterogeneity and bias detected. The Xbox® Kinect boxing platform produced higher MET (mean = 5.3) compared with the Nintendo® Wii™ boxing (mean = 3.8). Conclusion: The results of this review suggest that boxing exergames can produce intensity-adequate physical activity among younger adults that are beneficial for cardiometabolic improvements, regardless of platforms used. Exergaming boxing may be employed as an effective exercise tool to increase energy expenditure and physical activity level in young adults.

Matched MeSH terms: Boxing/physiology*; Energy Metabolism/physiology; Oxygen Consumption/physiology
Characterization of objects by electrosensing fish based on the first order polarization tensor

Khairuddin TK, Lionheart WR

Bioinspir Biomim, 2016 09 06;11(5):055004.
PMID: 27596986 DOI: 10.1088/1748-3190/11/5/055004

Weakly electric fish generate electric current and use hundreds of voltage sensors on the surface of their body to navigate and locate food. Experiments (von der Emde and Fetz 2007 J. Exp. Biol. 210 3082-95) show that they can discriminate between differently shaped conducting or insulating objects by using electrosensing. One approach to electrically identify and characterize the object with a lower computational cost rather than full shape reconstruction is to use the first order polarization tensor (PT) of the object. In this paper, by considering experimental work on Peters' elephantnose fish Gnathonemus petersii, we investigate the possible role of the first order PT in the ability of the fish to discriminate between objects of different shapes. We also suggest some experiments that might be performed to further investigate the role of the first order PT in electrosensing fish. Finally, we speculate on the possibility of electrical cloaking or camouflage in prey of electrosensing fish and what might be learnt from the fish in human remote sensing.

Matched MeSH terms: Biological Mimicry/physiology*; Electric Fish/physiology*; Form Perception/physiology*
Stored blood. A summary of the behaviour of normal blood stored outside the body, the sources of supply, and the methods for its preservation

Macgregor RGS

Journal of the Malaya Branch of British Medical Association, 1939;3:119-27.

Matched MeSH terms: Physiology
Fulltext Analysis of anthropometrics and mechanomyography signals as forearm flexion, pronation and supination torque predictors

Talib I, Sundaraj K, Hussain J, Lam CK, Ahmad Z

Sci Rep, 2022 Sep 27;12(1):16086.
PMID: 36168025 DOI: 10.1038/s41598-022-20223-6

This study aimed to analyze anthropometrics and mechanomyography (MMG) signals as forearm flexion, pronation, and supination torque predictors. 25 young, healthy, male participants performed isometric forearm flexion, pronation, and supination tasks from 20 to 100% maximal voluntary isometric contraction (MVIC) while maintaining 90° at the elbow joint. Nine anthropometric measures were recorded, and MMG signals from the biceps brachii (BB), brachialis (BRA), and brachioradialis (BRD) muscles were digitally acquired using triaxial accelerometers. These were then correlated with torque values. Significant positive correlations were found for arm circumference (CA) and MMG root mean square (RMS) values with flexion torque. Flexion torque might be predicted using CA (r = 0.426-0.575), a pseudo for muscle size while MMGRMS (r = 0.441), an indication of muscle activation.

Matched MeSH terms: Pronation/physiology; Supination/physiology; Muscle, Skeletal/physiology
Reproductive biology of Nemipterus japonicus (Bloch, 1791) from the coastal waters of Bintulu (South China Sea), Sarawak, Malaysia

Nettely T, Rajaee AH, Denil NA, Idris MH, Nesarul MH, Amin SMN, et al.

J Environ Biol, 2016 07;37(4 Spec No):715-24.
PMID: 28779731

Samples of threadfin breams Nemipterus japonicus were collected from a village in Kuala Nyalau and a fish landing centre at Bintulu from April 2013 to March 2014. A total of 360 individuals of N. japonicus (214 male and 146 female) were used in this reproductive study.? The total length (TL) of individuals were measured to the nearest 0.1 cm and body weight (BW) was recorded to the nearest 0.1 g. Month-wise distribution of the sexes was significantly higher for males in September and March, while in the month of May the number of females was significantly higher (X(2) = 6.53; P < 0.05). Males showed a preponderance in the size-class of 19.0-20.9 cm (X(2) = 80.24; P < 0.001), 21.0 -22.9 cm (X(2) = 56.39; P < 0.001) and 23.0 -24.9 cm (X(2) = 17; P < 0.001). The gonadosomatic index (GSI) values of N. japonicus ranged from 0.07 to 0.19 for males and 0.34 to 4.99 for females. Females had higher GSI than males throughout the study period. For males, a higher GSI (0.11-0.19) was observed during January to February, while it was found to be higher (2.73-4.99) for females during January to March, indicating the spawning season. The present study revealed that ovarian maturity based on histological analysis of N. japonicus was classified into seven stages namely, immature (I), immature (II), maturing (III), mature (IV), ripe (V), spawning (VI) and spent (VII). The fecundity of N. japonicus was estimated to be within a range of 19221 to 85923 with higher GSI (3.08-6.78) from the coastal waters of Bintulu, Sarawak.

Matched MeSH terms: Fishes/physiology*; Ovary/physiology; Reproduction/physiology*
Food and feeding habits of Omobranchus sp. (Blenniidae: Omobranchini) larvae in the Seagrass-Mangrove ecosystem of Johor Strait, Malaysia

Ara R, Arshad A, Amin SMN, Ghaffar MA

J Environ Biol, 2016 07;37(4 Spec No):735-43.
PMID: 28779733

The stomach contents of Omobranchus sp. (family Blenniidae) larvae were investigated in a seagrass-mangrove based ecosystem in Johor Strait, Malaysia from October 2007 to September 2008. Specimens of larval fish were collected through subsurface towing of a Bongo net from five different stations. The stomach sacs of 267 Omobranchus sp. larvae were separated and observed, which comprised of 24 significant food stuffs belonging to 6 main groups viz. phytoplankton (62.45%), zooplankton (18.24%), algae (5.56%), plant-like particles (5.75%), debris (4.22%) and unidentified particles (2.03%). In situ water parameters were also measured throughout the sampling cruises. There was a strong and significant positive correlation between stomach phytoplankton and salinity (r = 0.658, p < 0.05).? Canonical correlation analysis indicated a weak relationship (29.8%) between stomach contents and physico-chemical parameters. Only salinity appeared to be the controlling factor for the stomach contents of Omobranchus sp. larvae in the investigated area. Based on the stomach content analysis, it could be concluded that Omobranchus sp. were mainly herbivorous during the larval stages. ?

Matched MeSH terms: Feeding Behavior/physiology*; Fishes/physiology*; Larva/physiology
Diversity of pollination ecology in the Schismatoglottis Calyptrata Complex Clade (Araceae)

Hoe YC, Gibernau M, Wong SY

Plant Biol (Stuttg), 2018 May;20(3):563-578.
PMID: 29316090 DOI: 10.1111/plb.12687

Field studies integrating pollination investigations with an assessment of floral scent composition and thermogenesis in tropical aroids are rather few. Thus, this study aimed to investigate the pollination biology of nine species belonging to Schismatoglottis Calyptrata Complex Clade. The flowering mechanism, visiting insect activities, reproductive system, thermogenesis and floral scent composition were examined. Anthesis for all species started at dawn and lasted 25-29 h. Colocasiomyia (Diptera, Drosophilidae) are considered the main pollinators for all the investigated species. Cycreon (Coleoptera, Hydrophilidae) are considered secondary pollinators as they are only present in seven of the nine host plants, despite the fact that they are the most effective pollen carrier, carrying up to 15 times more pollen grains than Colocasiomyia flies. However, the number of Colocasiomyia individuals was six times higher than Cycreon beetles. Chaloenus (Chrysomelidae, Galeuricinae) appeared to be an inadvertent pollinator. Atheta (Coleoptera, Staphylinidae) is considered a floral visitor in most investigated species of the Calyptrata Complex Clade in Sarawak, but a possible pollinator in S. muluensis. Chironomidae midges and pteromalid wasps are considered visitors in S. calyptrata. Thermogenesis in a biphasic pattern was observed in inflorescences of S. adducta, S. calyptrata, S. giamensis, S. pseudoniahensis and S. roh. The first peak occurred during pistillate anthesis; the second peak during staminate anthesis. Inflorescences of all investigated species of Calyptrata Complex Clade emitted four types of ester compound, with methyl ester-3-methyl-3-butenoic acid as a single major VOC (volatile organic compound). The appendix, pistillate zone, staminate zone and spathe emitted all these compounds. A mixed fly-beetle pollination system is considered an ancestral trait in the Calyptrata Complex Clade, persisting in Sarawak taxa, whereas the marked reduction of interpistillar staminodes in taxa from Peninsular Malaysia and especially, Ambon, Indonesia, is probably linked to a shift in these taxa to a fly-pollinated system.

Matched MeSH terms: Beetles/physiology; Diptera/physiology; Insects/physiology; Pollen/physiology; Thermogenesis/physiology; Araceae/physiology*; Flowers/physiology; Pollination/physiology*
Fulltext Higher-order Brain Areas Associated with Real-time Functional MRI Neurofeedback Training of the Somato-motor Cortex

Auer T, Dewiputri WI, Frahm J, Schweizer R

Neuroscience, 2018 May 15;378:22-33.
PMID: 27133575 DOI: 10.1016/j.neuroscience.2016.04.034

Neurofeedback (NFB) allows subjects to learn self-regulation of neuronal brain activation based on information about the ongoing activation. The implementation of real-time functional magnetic resonance imaging (rt-fMRI) for NFB training now facilitates the investigation into underlying processes. Our study involved 16 control and 16 training right-handed subjects, the latter performing an extensive rt-fMRI NFB training using motor imagery. A previous analysis focused on the targeted primary somato-motor cortex (SMC). The present study extends the analysis to the supplementary motor area (SMA), the next higher brain area within the hierarchy of the motor system. We also examined transfer-related functional connectivity using a whole-volume psycho-physiological interaction (PPI) analysis to reveal brain areas associated with learning. The ROI analysis of the pre- and post-training fMRI data for motor imagery without NFB (transfer) resulted in a significant training-specific increase in the SMA. It could also be shown that the contralateral SMA exhibited a larger increase than the ipsilateral SMA in the training and the transfer runs, and that the right-hand training elicited a larger increase in the transfer runs than the left-hand training. The PPI analysis revealed a training-specific increase in transfer-related functional connectivity between the left SMA and frontal areas as well as the anterior midcingulate cortex (aMCC) for right- and left-hand trainings. Moreover, the transfer success was related with training-specific increase in functional connectivity between the left SMA and the target area SMC. Our study demonstrates that NFB training increases functional connectivity with non-targeted brain areas. These are associated with the training strategy (i.e., SMA) as well as with learning the NFB skill (i.e., aMCC and frontal areas). This detailed description of both the system to be trained and the areas involved in learning can provide valuable information for further optimization of NFB trainings.

Matched MeSH terms: Hand/physiology; Imagination/physiology; Learning/physiology*; Motor Cortex/physiology*; Motor Skills/physiology*; Neural Pathways/physiology; Somatosensory Cortex/physiology*; Neurofeedback/physiology*
Fulltext A gene co-expression network model identifies yield-related vicinity networks in Jatropha curcas shoot system

Govender N, Senan S, Mohamed-Hussein ZA, Wickneswari R

Sci Rep, 2018 Jun 15;8(1):9211.
PMID: 29907786 DOI: 10.1038/s41598-018-27493-z

The plant shoot system consists of reproductive organs such as inflorescences, buds and fruits, and the vegetative leaves and stems. In this study, the reproductive part of the Jatropha curcas shoot system, which includes the aerial shoots, shoots bearing the inflorescence and inflorescence were investigated in regard to gene-to-gene interactions underpinning yield-related biological processes. An RNA-seq based sequencing of shoot tissues performed on an Illumina HiSeq. 2500 platform generated 18 transcriptomes. Using the reference genome-based mapping approach, a total of 64 361 genes was identified in all samples and the data was annotated against the non-redundant database by the BLAST2GO Pro. Suite. After removing the outlier genes and samples, a total of 12 734 genes across 17 samples were subjected to gene co-expression network construction using petal, an R library. A gene co-expression network model built with scale-free and small-world properties extracted four vicinity networks (VNs) with putative involvement in yield-related biological processes as follow; heat stress tolerance, floral and shoot meristem differentiation, biosynthesis of chlorophyll molecules and laticifers, cell wall metabolism and epigenetic regulations. Our VNs revealed putative key players that could be adapted in breeding strategies for J. curcas shoot system improvements.

Matched MeSH terms: Gene Expression Regulation, Plant/physiology*; Epigenesis, Genetic/physiology*; Gene Regulatory Networks/physiology*
Bulbar signs in normal population

Lim KS, Hew YC, Lau HK, Lim TS, Tan CT

Can J Neurol Sci, 2009 Jan;36(1):60-4.
PMID: 19294890

BACKGROUND AND OBJECTIVES: There is lack of published data on bulbar signs among the healthy population. This study aims to determine the range of normality of bulbar signs particularly among the elderly.
METHODS: Systemic examination of bulbar signs was carried out according to a predetermined protocol on a cohort of young and elderly healthy subjects.
RESULTS: A total of 206 subjects were recruited in the study, 104 young adults with mean age of 20 years, and 102 elderly with mean age of 73 years. Uvula deviation was seen in 28 (26.9%) young subjects and 22 (21.6%) elderly. Irregular tongue border was seen in 17 subjects, unilateral in 4 subjects. Fourteen (6.8%) subjects had deviation on tongue protrusion. Occasional tremor of tongue on protrusion is common in both young and old. Persistent (severe) tongue tremor on protrusion was seen in 18.6% of the elderly, and 4.8% of the young. None of the subjects had tremor of tongue at rest. In gag reflex, absence of gagging response was common in elderly, seen in two thirds of the subjects on stimulation of the posterior pharyngeal wall. However, all the subjects had uvular movement. Habituation or suppression of gagging response was seen in close to 90% of young males.
CONCLUSION: There is wide range of normality in bulbar signs in normal population, particularly among the elderly.

Matched MeSH terms: Aging/physiology; Postural Balance/physiology; Gagging/physiology; Habituation, Psychophysiologic/physiology; Movement/physiology*; Palate, Soft/physiology; Reflex/physiology; Speech/physiology; Tongue/physiology*; Uvula/physiology*
Differential Effects of 7 and 16 Groups of Muscle Relaxation Training Following Repeated Submaximal Intensity Exercise in Young Football Players

Sharifah Maimunah SM, Hashim HA

Percept Mot Skills, 2016 Feb;122(1):227-37.
PMID: 27420318 DOI: 10.1177/0031512515625383

This study compares two versions of progressive muscle relaxation (PMR) training (7 and 16 muscle groups) on oxygen consumption (VO2), heart rates, rating of perceived exertion and choice reaction time. Football (soccer) players (N = 26; M age = 13.4 yr., SD = 0.5) were randomly assigned to either 7 muscle groups PMR, 16 muscle groups PMR, or a control group. PMR training requires the participants to tense a muscle, hold the muscle contraction, and then relax it. Measurement was conducted prior to and after the completion of 12 sessions of PMR. The dependent variables were measured following four bouts of intermittent exercise consisting of 12 min. of running at 60% VO2max for 10 min. followed by running at 90% VO2max for 2 min. with a 3-min. rest for each bout. Lower VO2, heart rate, perceived exertion, and quicker reaction time were expected in both relaxation groups compared to the control group. The results revealed a significant reduction in heart rates and choice reaction time for both relaxation groups, but the longer version produced significantly quicker choice reaction time.

Matched MeSH terms: Physical Exertion/physiology*; Heart Rate/physiology*; Muscle Contraction/physiology; Muscle Relaxation/physiology*; Oxygen Consumption/physiology*; Reaction Time/physiology; Rest/physiology; Running/physiology; Soccer/physiology*; Exercise/physiology*
Effects of action observation on corticospinal excitability: Muscle specificity, direction, and timing of the mirror response

Naish KR, Houston-Price C, Bremner AJ, Holmes NP

Neuropsychologia, 2014 11;64:331-48.
PMID: 25281883 DOI: 10.1016/j.neuropsychologia.2014.09.034

Many human behaviours and pathologies have been attributed to the putative mirror neuron system, a neural system that is active during both the observation and execution of actions. While there are now a very large number of papers on the mirror neuron system, variations in the methods and analyses employed by researchers mean that the basic characteristics of the mirror response are not clear. This review focuses on three important aspects of the mirror response, as measured by modulations in corticospinal excitability: (1) muscle specificity; (2) direction; and (3) timing of modulation. We focus mainly on electromyographic (EMG) data gathered following single-pulse transcranial magnetic stimulation (TMS), because this method provides precise information regarding these three aspects of the response. Data from paired-pulse TMS paradigms and peripheral nerve stimulation (PNS) are also considered when we discuss the possible mechanisms underlying the mirror response. In this systematic review of the literature, we examine the findings of 85 TMS and PNS studies of the human mirror response, and consider the limitations and advantages of the different methodological approaches these have adopted in relation to discrepancies between their findings. We conclude by proposing a testable model of how action observation modulates corticospinal excitability in humans. Specifically, we propose that action observation elicits an early, non-specific facilitation of corticospinal excitability (at around 90ms from action onset), followed by a later modulation of activity specific to the muscles involved in the observed action (from around 200ms). Testing this model will greatly advance our understanding of the mirror mechanism and provide a more stable grounding on which to base inferences about its role in human behaviour.

Matched MeSH terms: Motor Activity/physiology; Motor Cortex/physiology; Pyramidal Tracts/physiology*; Visual Perception/physiology*; Muscle, Skeletal/physiology*; Evoked Potentials, Motor/physiology*; Mirror Neurons/physiology*
Monitoring in the Western Pacific region shows evidence of seagrass decline in line with global trends

Short FT, Coles R, Fortes MD, Victor S, Salik M, Isnain I, et al.

Mar Pollut Bull, 2014 Jun 30;83(2):408-16.
PMID: 24746094 DOI: 10.1016/j.marpolbul.2014.03.036

Seagrass systems of the Western Pacific region are biodiverse habitats, providing vital services to ecosystems and humans over a vast geographic range. SeagrassNet is a worldwide monitoring program that collects data on seagrass habitats, including the ten locations across the Western Pacific reported here where change at various scales was rapidly detected. Three sites remote from human influence were stable. Seagrasses declined largely due to increased nutrient loading (4 sites) and increased sedimentation (3 sites), the two most common stressors of seagrass worldwide. Two sites experienced near-total loss from of excess sedimentation, followed by partial recovery once sedimentation was reduced. Species shifts were observed at every site with recovering sites colonized by pioneer species. Regulation of watersheds is essential if marine protected areas are to preserve seagrass meadows. Seagrasses in the Western Pacific experience stress due to human impacts despite the vastness of the ocean area and low development pressures.

Matched MeSH terms: Alismatidae/physiology*
Fulltext Combining ability of pod yield and related traits of groundnut (Arachis hypogaea L.) under salinity stress

Azad MA, Shah-E-Alam M, Hamid MA, Rafii MY, Malek MA

ScientificWorldJournal, 2014;2014:589586.
PMID: 24737982 DOI: 10.1155/2014/589586

A study was performed using 6 × 6 F1 diallel population without reciprocals to assess the mode of inheritance of pod yield and related traits in groundnut with imposed salinity stress. Heterosis was found for pod number and yield. Data on general and specific combining ability (gca and sca) indicated additive and nonadditive gene actions. The gca: sca ratios were much less than unity suggesting predominant role of nonadditive gene effects. Cultivars "Binachinabadam-2" and "Dacca-1" and mutant M6/25/64-82 had the highest, second highest, and third highest pod number, as well as gca values, respectively. These two cultivars and another mutant M6/15/70-19 also had the highest, second highest, and third highest pod yield, as well as gca values, respectively. Therefore, "Dacca-1", "Binachinabadam-2", M6/25/64-82, and M6/15/70-19 could be used as source of salinity tolerance. Cross combinations showing high sca effects arising from parents with high and low gca values for any trait indicate the influence of nonadditive genes on their expression. Parents of these crosses can be used for biparental mating or reciprocal recurrent selection for developing high yielding varieties. Crosses with high sca effects having both parents with good gca effects could be exploited by pedigree breeding to get transgressive segregants.

Matched MeSH terms: Arachis/physiology*
Fulltext Geographical pattern and environmental correlates of regional-scale general flowering in Peninsular Malaysia

Numata S, Yasuda M, Suzuki RO, Hosaka T, Noor NS, Fletcher CD, et al.

PLoS One, 2013;8(11):e79095.
PMID: 24260159 DOI: 10.1371/journal.pone.0079095

In South-East Asian dipterocarp forests, many trees synchronize their reproduction at the community level, but irregularly, in a phenomenon known as general flowering (GF). Several proximate cues have been proposed as triggers for the synchronization of Southeast Asian GF, but the debate continues, as many studies have not considered geographical variation in climate and flora. We hypothesized that the spatial pattern of GF forests is explained by previously proposed climatic cues if there are common cues for GF among regions. During the study, GF episodes occurred every year, but the spatial occurrence varied considerably from just a few forests to the whole of Peninsular Malaysia. In 2001, 2002 and 2005, minor and major GF occurred widely throughout Peninsular Malaysia (GF2001, GF2002, and GF2005), and the geographical patterns of GF varied between the episodes. In the three regional-scale GF episodes, most major events occurred in regions where prolonged drought (PD) had been recorded prior, and significant associations between GF scores and PD were found in GF2001 and GF2002. However, the frequency of PD was higher than that of GF throughout the peninsula. In contrast, low temperature (LT) was observed during the study period only before GF2002 and GF2005, but there was no clear spatial relationship between GF and LT in the regional-scale episodes. There was also no evidence that last GF condition influenced the magnitude of GF. Thus, our results suggest that PD would be essential to trigger regional-scale GF in the peninsula, but also that PD does not fully explain the spatial and temporal patterns of GF. The coarse relationships between GF and the proposed climatic cues may be due to the geographical variation in proximate cues for GF, and the climatic and floristic geographical variations should be considered to understand the proximate factors of GF.

Matched MeSH terms: Trees/physiology*
Fulltext The effect of relaxin on the musculoskeletal system

Dehghan F, Haerian BS, Muniandy S, Yusof A, Dragoo JL, Salleh N

Scand J Med Sci Sports, 2014 Aug;24(4):e220-9.
PMID: 24283470 DOI: 10.1111/sms.12149

Relaxin is a hormone structurally related to insulin and insulin-like growth factor, which exerts its regulatory effect on the musculoskeletal and other systems through binding to its receptor in various tissues, mediated by different signaling pathways. Relaxin alters the properties of cartilage and tendon by activating collagenase. This hormone is also involved in bone remodeling and healing of injured ligaments and skeletal muscle. In this review, we have summarized the literature on the effect of relaxin in musculoskeletal system to provide a broad perspective for future studies in this field.

Matched MeSH terms: Bone and Bones/physiology; Cartilage/physiology; Ligaments/physiology*; Relaxin/physiology*; Synovial Membrane/physiology; Tendons/physiology; Muscle, Skeletal/physiology*
Fulltext Impacts of intensive logging on the trophic organisation of ant communities in a biodiversity hotspot

Woodcock P, Edwards DP, Newton RJ, Vun Khen C, Bottrell SH, Hamer KC

PLoS One, 2013;8(4):e60756.
PMID: 23593302 DOI: 10.1371/journal.pone.0060756

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.

Matched MeSH terms: Ants/physiology*
Record of Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae) preying on Metrogaleruca obscura Degeer (Coleoptera: Chrysomelidae)

Moura LA, Grazia J

Neotrop. Entomol., 2011 Oct;40(5):619-21.
PMID: 22068951

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.

Matched MeSH terms: Hemiptera/physiology*

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