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  1. Transient electro-magneto-hydrodynamic two-phase blood flow and thermal transport through a capillary vessel
    Mirza IA, Abdulhameed M, Vieru D, Shafie S
    Comput Methods Programs Biomed, 2016 Dec;137:149-166.
    PMID: 28110721 DOI: 10.1016/j.cmpb.2016.09.014
    Therapies with magnetic/electromagnetic field are employed to relieve pains or, to accelerate flow of blood-particles, particularly during the surgery. In this paper, a theoretical study of the blood flow along with particles suspension through capillary was made by the electro-magneto-hydrodynamic approach. Analytical solutions to the non-dimensional blood velocity and non-dimensional particles velocity are obtained by means of the Laplace transform with respect to the time variable and the finite Hankel transform with respect to the radial coordinate. The study of thermally transfer characteristics is based on the energy equation for two-phase thermal transport of blood and particles suspension with viscous dissipation, the volumetric heat generation due to Joule heating effect and electromagnetic couple effect. The solution of the nonlinear heat transfer problem is derived by using the velocity field and the integral transform method. The influence of dimensionless system parameters like the electrokinetic width, the Hartman number, Prandtl number, the coefficient of heat generation due to Joule heating and Eckert number on the velocity and temperature fields was studied using the Mathcad software. Results are presented by graphical illustrations.
    Matched MeSH terms: Capillaries/physiology*
  2. Population studies on a polymorphic prosobranch snail (Clithon (Pictoneritina) oualaniensis Lesson)
    Grüneberg H
    Philos Trans R Soc Lond B Biol Sci, 1976 Sep 16;275(940):385-437.
    PMID: 10588
    Matched MeSH terms: Snails/physiology*
  3. Unravelling the adaptation strategies employed by Glaciozyma antarctica PI12 on Antarctic sea ice
    Bharudin I, Abu Bakar MF, Hashim NHF, Mat Isa MN, Alias H, Firdaus-Raih M, et al.
    Mar Environ Res, 2018 Jun;137:169-176.
    PMID: 29598997 DOI: 10.1016/j.marenvres.2018.03.007
    Glaciozyma antarctica PI12, is a psychrophilic yeast isolated from Antarctic sea. In this work, Expressed Sequence Tags (EST) from cells exposed to three different temperatures; 15 °C, 0 °C and -12 °C were generated to identify genes associated with cold adaptation. A total of 5376 clones from each library were randomly picked and sequenced. Comparative analyses from the resulting ESTs in each condition identified several groups of genes required for cold adaptation. Additionally, 319 unique transcripts that encoded uncharacterised functions were identified in the -12 °C library and are currently unique to G. antarctica. Gene expression analysis using RT-qPCR revealed two of the unknown genes to be up-regulated at -12 °C compared to 0 °C and 15 °C. These findings further contribute to the collective knowledge into G. antarctica cold adaptation and as a resource for understanding the ecological and physiological tolerance of psychrophilic microbes in general.
    Matched MeSH terms: Basidiomycota/physiology*
  4. Fulltext Effect of tropical forest disturbance on the competitive interactions within a diverse ant community
    Gray REJ, Ewers RM, Boyle MJW, Chung AYC, Gill RJ
    Sci Rep, 2018 03 23;8(1):5131.
    PMID: 29572517 DOI: 10.1038/s41598-018-23272-y
    Understanding how anthropogenic disturbance influences patterns of community composition and the reinforcing interactive processes that structure communities is important to mitigate threats to biodiversity. Competition is considered a primary reinforcing process, yet little is known concerning disturbance effects on competitive interaction networks. We examined how differences in ant community composition between undisturbed and disturbed Bornean rainforest, is potentially reflected by changes in competitive interactions over a food resource. Comparing 10 primary forest sites to 10 in selectively-logged forest, we found higher genus richness and diversity in the primary forest, with 18.5% and 13.0% of genera endemic to primary and logged respectively. From 180 hours of filming bait cards, we assessed ant-ant interactions, finding that despite considered aggression over food sources, the majority of ant interactions were neutral. Proportion of competitive interactions at bait cards did not differ between forest type, however, the rate and per capita number of competitive interactions was significantly lower in logged forest. Furthermore, the majority of genera showed large changes in aggression-score with often inverse relationships to their occupancy rank. This provides evidence of a shuffled competitive network, and these unexpected changes in aggressive relationships could be considered a type of competitive network re-wiring after disturbance.
    Matched MeSH terms: Ants/physiology*
  5. Fulltext Living with marginal coral communities: Diversity and host-specificity in coral-associated barnacles in the northern coral distribution limit of the East China Sea
    Chan BKK, Xu G, Kim HK, Park JH, Kim W
    PLoS One, 2018;13(5):e0196309.
    PMID: 29715264 DOI: 10.1371/journal.pone.0196309
    Corals and their associated fauna are extremely diverse in tropical waters and form major reefs. In the high-latitude temperate zone, corals living near their distribution limit are considered marginal communities because they are particularly extremely sensitive to environmental and climatic changes. In this study, we examined the diversity and host usage of coral-associated barnacles on Jeju Island, Korea, the northern coral distribution limit in the East China Sea. In this study, only three coral-associated barnacles-from two genera in two subfamilies-were collected. The Pyrgomatinid barnacles Cantellius arcuatus and Cantellius cf. euspinulosum were found only on the corals Montipora millepora and Alveopora japonica, respectively. The Megatrematinid barnacle Pyrgomina oulastreae, relatively a generalist, was found on Psammocora spp. (both profundacella and albopicta) and Oulastrea crispata corals. The host usage of these three barnacles does not overlap. DNA barcode sequences of the C. arcuatus specimens collected in the present study matched those collected in Kochi in Japan, Taiwan, Malaysia and Papua New Guinea, suggesting that this species has a wide geographical distribution. C. arcuatus covers a wider host range in Taiwan waters, inhabiting Montipora spp. and Porites spp., which suggests that the host specificity of coral-associated barnacles varies with host availability. C. cf. euspinulosum probably has a very narrow distribution and host usage. The sequences of C. cf. euspinulosum on Jeju Island do not match those of any known sequences of Cantellius barnacles in the Indo-Pacific region. P. oulastreae probably prefers cold water because it has been reported in temperate regions. Coral-associated barnacles in marginal communities have considerably lower diversity than their subtropical and tropical counterparts. When host availability is limited, marginal coral-associated barnacles exhibit higher host specificity than those in subtropical and tropical reef systems.
    Matched MeSH terms: Thoracica/physiology*
  6. A Systematic Review for Human EEG Brain Signals Based Emotion Classification, Feature Extraction, Brain Condition, Group Comparison
    Hamada M, Zaidan BB, Zaidan AA
    J Med Syst, 2018 Jul 24;42(9):162.
    PMID: 30043178 DOI: 10.1007/s10916-018-1020-8
    The study of electroencephalography (EEG) signals is not a new topic. However, the analysis of human emotions upon exposure to music considered as important direction. Although distributed in various academic databases, research on this concept is limited. To extend research in this area, the researchers explored and analysed the academic articles published within the mentioned scope. Thus, in this paper a systematic review is carried out to map and draw the research scenery for EEG human emotion into a taxonomy. Systematically searched all articles about the, EEG human emotion based music in three main databases: ScienceDirect, Web of Science and IEEE Xplore from 1999 to 2016. These databases feature academic studies that used EEG to measure brain signals, with a focus on the effects of music on human emotions. The screening and filtering of articles were performed in three iterations. In the first iteration, duplicate articles were excluded. In the second iteration, the articles were filtered according to their titles and abstracts, and articles outside of the scope of our domain were excluded. In the third iteration, the articles were filtered by reading the full text and excluding articles outside of the scope of our domain and which do not meet our criteria. Based on inclusion and exclusion criteria, 100 articles were selected and separated into five classes. The first class includes 39 articles (39%) consists of emotion, wherein various emotions are classified using artificial intelligence (AI). The second class includes 21 articles (21%) is composed of studies that use EEG techniques. This class is named 'brain condition'. The third class includes eight articles (8%) is related to feature extraction, which is a step before emotion classification. That this process makes use of classifiers should be noted. However, these articles are not listed under the first class because these eight articles focus on feature extraction rather than classifier accuracy. The fourth class includes 26 articles (26%) comprises studies that compare between or among two or more groups to identify and discover human emotion-based EEG. The final class includes six articles (6%) represents articles that study music as a stimulus and its impact on brain signals. Then, discussed the five main categories which are action types, age of the participants, and number size of the participants, duration of recording and listening to music and lastly countries or authors' nationality that published these previous studies. it afterward recognizes the main characteristics of this promising area of science in: motivation of using EEG process for measuring human brain signals, open challenges obstructing employment and recommendations to improve the utilization of EEG process.
    Matched MeSH terms: Brain/physiology
  7. Short-term heat acclimation prior to a multi-day desert ultra-marathon improves physiological and psychological responses without compromising immune status
    Willmott AGB, Hayes M, Waldock KAM, Relf RL, Watkins ER, James CA, et al.
    J Sports Sci, 2017 Nov;35(22):2249-2256.
    PMID: 27935427 DOI: 10.1080/02640414.2016.1265142
    Multistage, ultra-endurance events in hot, humid conditions necessitate thermal adaptation, often achieved through short term heat acclimation (STHA), to improve performance by reducing thermoregulatory strain and perceptions of heat stress. This study investigated the physiological, perceptual and immunological responses to STHA prior to the Marathon des Sables. Eight athletes (age 42 ± 4 years and body mass 81.9 ± 15.0 kg) completed 4 days of controlled hyperthermia STHA (60 min·day‒1, 45°C and 30% relative humidity). Pre, during and post sessions, physiological and perceptual measures were recorded. Immunological measures were recorded pre-post sessions 1 and 4. STHA improved thermal comfort (P = 0.02), sensation (P = 0.03) and perceived exertion (P = 0.04). A dissociated relationship between perceptual fatigue and Tre was evident after STHA, with reductions in perceived Physical (P = 0.04) and General (P = 0.04) fatigue. Exercising Tre and HR did not change (P > 0.05) however, sweat rate increased 14% (P = 0.02). No changes were found in white blood cell counts or content (P > 0.05). Four days of STHA facilitates effective perceptual adaptations, without compromising immune status prior to an ultra-endurance race in heat stress. A greater physiological strain is required to confer optimal physiological adaptations.
    Matched MeSH terms: Running/physiology*
  8. Clinical features and management of Plasmodium knowlesi infections in humans
    Daneshvar C, William T, Davis TME
    Parasitology, 2018 01;145(1):18-31.
    PMID: 28122651 DOI: 10.1017/S0031182016002638
    Plasmodium knowlesi is a simian malaria of primarily the macaque species of South East Asia. While it was known that human infections could be induced during the years of malariotherapy, naturally occurring P. knowlesi human infections were thought to be rare. However, in 2004, knowlesi infections became recognized as an important infection amongst human populations in Sarawak, Malaysian Borneo. Since then, it has become recognized as a disease affecting people living and visiting endemic areas across South East Asia. Over the last 12 years, clinical studies have improved our understanding of this potentially fatal disease. In this review article the current literature is reviewed to give a comprehensive description of the disease and treatment.
    Matched MeSH terms: Plasmodium knowlesi/physiology*
  9. Microclimate and Physiological Effects in the Roosts of Cave Dwelling Bats: Implications in Roost Selection and Conservation in Sarawak, Malaysian Borneo
    Rajasegaran P, Shazali N, Khan FAA
    Zoolog Sci, 2018 12 04;35(6):521-527.
    PMID: 30520355 DOI: 10.2108/zs170144
    Bats play crucial ecological and economic roles. However, this group of mammals is largely threatened due to anthropogenic activities inside or around their caves. In the present study, we investigate the effects of cave microclimate and physiological parameters on bat roost preference in Fairy Cave Nature Reserve (Fairy Cave NR). The microclimate and physiological parameters including temperature (°C), relative humidity (RH), light intensity (lux), air flow, passage dimension (m), roost height (m) and distance of roost from nearest entrance (m) were measured. Results showed that Emballonura monticola, Hipposideros diadema, Hipposideros larvatus and Penthetor lucasi roost in Fairy Cave NR. These bats can be distinguished by their colony size, roost posture, spatial arrangement and position of their roost. Penthetor lucasi makes up the largest colony in the bright zone, whereas E. monticola has the smallest colony, occupying the twilight zone throughout the cave. Members from the family Hipposideridae roost in the dark portion of the cave with zero light intensity. Emballonura monticola utilizes the hottest roost in the cave compared to the other microbats, whereas H. diadema inhabits the coolest roost. Physiological parameters such as light intensity, passage dimension, and distance from nearest entrance are significant parameters in roosting preferences. These parameters should be monitored to ensure the sustainability of not only the aforementioned species, but also other species that roost in nearby caves of Bau limestone (Wind Cave Nature Reserve: with 13 recorded species).
    Matched MeSH terms: Chiroptera/physiology*
  10. Exploratory study on the natural ground electric current that flows through human body as a possible pathway for the therapeutic effects of beach going
    Neoh SL
    Complement Ther Med, 2018 Dec;41:161-168.
    PMID: 30477833 DOI: 10.1016/j.ctim.2018.09.017
    This paper explores the electrical nature of sandy beach and proposes a pathway for the therapeutic effects of beach going. The electric potential and current generated on the ground across the human body and resistors were measured. The ground was found to have a non-homogenous electric potential which generated a potential difference between any two points on the ground. A power curve, similar to a battery, in the nanowatt range was obtained. This power appeared to be stable across time but varies across ground location. Standing on the beach with dry feet did not allow any current in the micro-ampere range to conduct. But upon moistening the feet, the body electrical resistance was reduced by 94% and the ground potential difference across the two feet was sufficient to drive a micro-ampere range current through the body. This may be one reason for the therapeutic effects of being on the beach.
    Matched MeSH terms: Foot/physiology*
  11. Fulltext Improved Biobutanol Production in 2-L Simultaneous Saccharification and Fermentation with Delayed Yeast Extract Feeding and in-situ Recovery
    Salleh MSM, Ibrahim MF, Roslan AM, Abd-Aziz S
    Sci Rep, 2019 05 15;9(1):7443.
    PMID: 31092836 DOI: 10.1038/s41598-019-43718-1
    Simultaneous saccharification and fermentation (SSF) with delayed yeast extract feeding (DYEF) was conducted in a 2-L bioreactor equipped with in-situ recovery using a gas stripping in order to enhance biobutanol production from lignocellulosic biomass of oil palm empty fruit bunch (OPEFB). This study showed that 2.88 g/L of biobutanol has been produced from SSF with a similar yield of 0.23 g/g as compared to separate hydrolysis and fermentation (SHF). An increase of 42% of biobutanol concentration was observed when DYEF was introduced in the SSF at 39 h of fermentation operation. Biobutanol production was further enhanced up to 11% with a total improvement of 72% when in-situ recovery using a gas stripping was implemented to reduce the solvents inhibition in the bioreactor. In overall, DYEF and in-situ recovery were able to enhance biobutanol production in SSF.
    Matched MeSH terms: Fermentation/physiology
  12. The exchange of water and energy between a tropical peat forest and the atmosphere: Seasonal trends and comparison against other tropical rainforests
    Tang ACI, Stoy PC, Hirata R, Musin KK, Aeries EB, Wenceslaus J, et al.
    Sci Total Environ, 2019 Sep 15;683:166-174.
    PMID: 31132697 DOI: 10.1016/j.scitotenv.2019.05.217
    Tropical rainforests control the exchange of water and energy between the land surface and the atmosphere near the equator and thus play an important role in the global climate system. Measurements of latent (LE) and sensible heat exchange (H) have not been synthesized across global tropical rainforests to date, which can help place observations from individual tropical forests in a global context. We measured LE and H for four years in a tropical peat forest ecosystem in Sarawak, Malaysian Borneo using eddy covariance, and hypothesize that the study ecosystem will exhibit less seasonal variability in turbulent fluxes than other tropical ecosystems as soil water is not expected to be limiting in a tropical forested wetland. LE and H show little variability across seasons in the study ecosystem, with LE values on the order of 11 MJ m-2 day and H on the order of 3 MJ m-2 day-1. Annual evapotranspiration (ET) did not differ among years and averaged 1579 ± 47 mm year-1. LE exceeded characteristic values from other tropical rainforest ecosystems in the FLUXNET2015 database with the exception of GF-Guy near coastal French Guyana, which averaged 8-11 MJ m-2 day-1. The Bowen ratio (Bo) in tropical rainforests in the FLUXNET2015 database either exhibited little seasonal trend, one seasonal peak, or two peaks. Volumetric water content (VWC) and VPD explained a trivial amount of the variability of LE and Bo in some of the tropical rainforests including the study ecosystem, but were strong controls in others, suggesting differences in stomatal regulation and/or the partitioning between evaporation and transpiration. Results demonstrate important differences in the seasonal patterns in water and energy exchange across different tropical rainforest ecosystems that need to be understood to quantify how ongoing changes in tropical rainforest extent will impact the global climate system.
    Matched MeSH terms: Plant Transpiration/physiology*
  13. Cardiovascular autonomic effects of transcutaneous auricular nerve stimulation via the tragus in the rat involve spinal cervical sensory afferent pathways
    Mahadi KM, Lall VK, Deuchars SA, Deuchars J
    Brain Stimul, 2019 05 06;12(5):1151-1158.
    PMID: 31129152 DOI: 10.1016/j.brs.2019.05.002
    BACKGROUND: Electrical stimulation on select areas of the external auricular dermatome influences the autonomic nervous system. It has been postulated that activation of the Auricular Branch of the Vagus Nerve (ABVN) mediates such autonomic changes. However, the underlying neural pathways mediating these effects are unknown and, further, our understanding of the anatomical distribution of the ABVN in the auricle has now been questioned.

    OBJECTIVE: To investigate the effects of electrical stimulation of the tragus on autonomic outputs in the rat and probe the underlying neural pathways.

    METHODS: Central neuronal projections from nerves innervating the external auricle were investigated by injections of the transganglionic tracer cholera toxin B chain (CTB) into the right tragus of Wistar rats. Physiological recordings of heart rate, perfusion pressure, respiratory rate and sympathetic nerve activity were made in an anaesthetic free Working Heart Brainstem Preparation (WHBP) of the rat and changes in response to electrical stimulation of the tragus analysed.

    RESULTS: Neuronal tracing from the tragus revealed that the densest CTB labelling was within laminae III-IV of the dorsal horn of the upper cervical spinal cord, ipsilateral to the injection sites. In the medulla oblongata, CTB labelled afferents were observed in the paratrigeminal nucleus, spinal trigeminal tract and cuneate nucleus. Surprisingly, only sparse labelling was observed in the vagal afferent termination site, the nucleus tractus solitarius. Recordings made from rats at night time revealed more robust sympathetic activity in comparison to day time rats, thus subsequent experiments were conducted in rats at night time. Electrical stimulation was delivered across the tragus for 5 min. Direct recording from the sympathetic chain revealed a central sympathoinhibition by up to 36% following tragus stimulation. Sympathoinhibition remained following sectioning of the cervical vagus nerve ipsilateral to the stimulation site, but was attenuated by sectioning of the upper cervical afferent nerve roots.

    CONCLUSIONS: Inhibition of the sympathetic nervous system activity upon electrical stimulation of the tragus in the rat is mediated at least in part through sensory afferent projections to the upper cervical spinal cord. This challenges the notion that tragal stimulation is mediated by the auricular branch of the vagus nerve and suggests that alternative mechanisms may be involved.

    Matched MeSH terms: Afferent Pathways/physiology; Brain Stem/physiology; Heart Rate/physiology*; Sensory Receptor Cells/physiology*; Spinal Cord/physiology*; Vagus Nerve/physiology*; Solitary Nucleus/physiology
  14. The diet and feeding behavior of the black-and-white colobus (Colobus guereza) in the Kalinzu Forest, Uganda
    Matsuda I, Ihobe H, Tashiro Y, Yumoto T, Baranga D, Hashimoto C
    Primates, 2020 May;61(3):473-484.
    PMID: 32026152 DOI: 10.1007/s10329-020-00794-6
    One of the goals for primate feeding ecology is to understand the factors that affect inter- and intra-specific variations. Therefore, a detailed description of basic feeding ecology in as many populations as possible is necessary and warrants further understanding. The black-and-white colobus (Colobus guereza) or guereza is widely distributed in Africa and is one of the well-studied colobines in terms of their feeding; they demonstrate considerable variation in their diets in response to local conditions. We studied the diet of a group of guerezas in the Kalinzu Forest, Uganda, for over 30 consecutive months using behavioral observation (4308 h in total), phenology, and vegetation surveys. A total of 31 plant species were consumed by the study group. This study group was predominantly folivorous; the majority of their feeding time was involved in feeding on young leaves (87%). However, during certain times of the year, fruits and seeds accounted for 45% of monthly feeding time. Young leaves of Celtis durandii were by far the most important food, which constituted 58% of the total feeding records. There was a significant increase in the consumption of fruits and flowers once young leaf availability was low, but their consumption of fruits did not significantly increase even when fruit availability was high. Their monthly dietary diversity increased as the number of available plants with young leaves declined, suggesting that much of the dietary diversity in the study group may be attributable to the young leaf portion of their diet. Our findings may help contribute to a better understanding of the dietary adaptations and feeding ecology of guerezas in response to local environmental conditions.
    Matched MeSH terms: Colobus/physiology*
  15. Fulltext Termites can decompose more than half of deadwood in tropical rainforest
    Griffiths HM, Ashton LA, Evans TA, Parr CL, Eggleton P
    Curr Biol, 2019 02 18;29(4):R118-R119.
    PMID: 30779897 DOI: 10.1016/j.cub.2019.01.012
    Termite-mediated decomposition is an important, but often overlooked, component of the carbon cycle. Using a large-scale suppression experiment in Borneo, Griffiths et al. found that termites contribute between 58 and 64% of mass loss from dead wood.
    Matched MeSH terms: Isoptera/physiology*
  16. Special issue on Free Living Amoebae (FLA): Recent advances presented at the XVIIth International Meeting on the Biology and Pathogenicity of Free-Living Amoebae (FLAM, 2017), Zarzis, Tunisia
    Lorenzo-Morales J, Sifaoui I, Reyes-Batlle M, Lares-Villa F, Lares-Jiménez LF, Omaña-Molina M, et al.
    Exp Parasitol, 2019 May;200:36.
    PMID: 30902622 DOI: 10.1016/j.exppara.2019.03.010
    Matched MeSH terms: Amoeba/physiology*
  17. Fulltext Question classification based on Bloom's taxonomy cognitive domain using modified TF-IDF and word2vec
    Mohammed M, Omar N
    PLoS One, 2020;15(3):e0230442.
    PMID: 32191738 DOI: 10.1371/journal.pone.0230442
    The assessment of examination questions is crucial in educational institutes since examination is one of the most common methods to evaluate students' achievement in specific course. Therefore, there is a crucial need to construct a balanced and high-quality exam, which satisfies different cognitive levels. Thus, many lecturers rely on Bloom's taxonomy cognitive domain, which is a popular framework developed for the purpose of assessing students' intellectual abilities and skills. Several works have been proposed to automatically handle the classification of questions in accordance with Bloom's taxonomy. Most of these works classify questions according to specific domain. As a result, there is a lack of technique of classifying questions that belong to the multi-domain areas. The aim of this paper is to present a classification model to classify exam questions based on Bloom's taxonomy that belong to several areas. This study proposes a method for classifying questions automatically, by extracting two features, TFPOS-IDF and word2vec. The purpose of the first feature was to calculate the term frequency-inverse document frequency based on part of speech, in order to assign a suitable weight for essential words in the question. The second feature, pre-trained word2vec, was used to boost the classification process. Then, the combination of these features was fed into three different classifiers; K-Nearest Neighbour, Logistic Regression, and Support Vector Machine, in order to classify the questions. The experiments used two datasets. The first dataset contained 141 questions, while the other dataset contained 600 questions. The classification result for the first dataset achieved an average of 71.1%, 82.3% and 83.7% weighted F1-measure respectively. The classification result for the second dataset achieved an average of 85.4%, 89.4% and 89.7% weighted F1-measure respectively. The finding from this study showed that the proposed method is significant in classifying questions from multiple domains based on Bloom's taxonomy.
    Matched MeSH terms: Cognition/physiology*
  18. Fulltext Probiotic Properties of Bacillus Strains Isolated from Stingless Bee (Heterotrigona itama) Honey Collected across Malaysia
    Zulkhairi Amin FA, Sabri S, Ismail M, Chan KW, Ismail N, Mohd Esa N, et al.
    Int J Environ Res Public Health, 2019 12 31;17(1).
    PMID: 31906055 DOI: 10.3390/ijerph17010278
    This study aimed to isolate, identify, and evaluate the probiotic properties of Bacillus species from honey of the stingless bee Heterotrigona itama. Bacillus spp. were isolated from five different H. itama meliponicultures, and the isolates were characterized through Gram-staining and a catalase test. Tolerance to acidic conditions and bile salt (0.3%), hydrophobicity, and autoaggregation tests were performed to assess the probiotic properties of the selected isolates, B. amyloliquefaciens HTI-19 and B. subtilis HTI-23. Both Bacillus isolates exhibited excellent antimicrobial activity against both Gram-positive and Gram-negative bacteria and possessed significantly high survival rates in 0.3% bile solution for 3 h. Their survival rates in acidic conditions were also comparable to a commercial probiotic strain, Lactobacillus rhamnosus GG. Interestingly, the hydrophobicity and autoaggregation percentage showed no significant difference from L. rhamnosus GG, a commercial probiotic strain. The results from this study suggest that B. amyloliquefaciens HTI-19 and B. subtilis HTI-23 isolated from stingless bee honey have considerably good probiotic properties. Therefore, more studies should be done to investigate the effects of these bacteria cultures on gastrointestinal health.
    Matched MeSH terms: Bacillus/physiology*
  19. Dynamical behaviors and optimal harvesting of an intraguild prey-predator fishery model with Michaelis-Menten type predator harvesting
    Ang TK, Safuan HM
    Biosystems, 2021 Apr;202:104357.
    PMID: 33486091 DOI: 10.1016/j.biosystems.2021.104357
    The present paper discusses the dynamics and optimal harvesting of an intraguild prey-predator fishery model by incorporating the nonlinear Michaelis-Menten type of harvesting in predator. To our knowledge, there is limited literature working on Michaelis-Menten type of harvesting in a three species intraguild model with variable carrying capacity. The carrying capacity is proportional to the density of biotic resource. The existence of the possible equilibria has been studied along with the stability criteria. We consider the impact of predator fish harvesting as the bifurcation parameter to analyze the long time behavior of the proposed system. From the economic perspective, bionomic equilibrium of the system is studied and optimal harvesting policy is derived with the assistance of Pontryagin Maximum Principle. Finally, numerical results are presented to verify our analytical results. It is shown that in the bifurcation diagrams, the system can exhibit transcritical and Hopf bifurcations in the neighborhood of coexistence equilibrium at low and relatively high level of predator harvesting respectively. Interestingly, the system enters to a bistable region where both the coexistence and predator-free equilibria can be stable depending on the initial values. This bistable behavior might be novel to the existing literature that studied intraguild models with variable carrying capacity. The objective of this study is to derive the optimal threshold for the predator harvesting that gives maximum financial profit while sustaining the fishery resources.
    Matched MeSH terms: Predatory Behavior/physiology*
  20. A Laboratory Maintenance Regime for a Fungus-Growing Termite Macrotermes gilvus (Blattodea: Termitidae)
    Lee CC, Lee CY
    J Econ Entomol, 2015 Jun;108(3):1243-50.
    PMID: 26470252 DOI: 10.1093/jee/tov112
    The optimum maintenance conditions of the fungus-growing termite, Macrotermes gilvus (Hagen) (Blattodea: Termitidae), in the laboratory were studied. Termites were kept on a matrix of moist sand and with fungus comb as food. The survival of groups of termites was measured when maintained at different population densities by changing group size and container volume. Larger groups (≥0.6 g) were more vigorous and had significant higher survival rates than smaller groups (≤0.3 g). The population density for optimal survival of M. gilvus is 0.0025 g per container volume (ml) or 0.0169 g per matrix volume (cm(3)), i.e., 1.2 g of termites kept in a 480-ml container filled with 71 cm3 of sand. In termite groups of smaller size (i.e., 0.3 g) or groups maintained in smaller container (i.e., 100 ml) the fungus comb was overgrown with Xylaria spp., and subsequently all termites died within the study period. The insufficient number of workers for regulating the growth of unwanted fungi other than Termitomyces spp. in the fungus comb is the most likely reason. Unlike some other mound-building termite species, M. gilvus showed satisfactory survival when maintained in non-nutritious matrix (i.e., sand). There was no significant difference in the survival rate between different colonies of M. gilvus (n=5), with survival in the range of 78.5-84.4% after 4 wk. Advances in the maintenance of Macrotermes will enable researchers to study with more biological relevance many aspects of the biology, behavior, and management of this species.
    Matched MeSH terms: Isoptera/physiology*
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