Displaying publications 581 - 600 of 4601 in total

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  1. Ruslin F, Matsuda I, Md-Zain BM
    Primates, 2019 Jan;60(1):41-50.
    PMID: 30564972 DOI: 10.1007/s10329-018-00705-w
    Knowledge about the feeding ecology and dietary overlap of sympatric primates is essential for understanding how animals avoid or reduce interspecific competition. From April 2014 to March 2015, we investigated the feeding ecologies of two sympatric primates, a hindgut fermenter, the long-tailed macaque (Macaca fascicularis) and a foregut fermenter, the dusky langur (Trachypithecus obscurus obscurus), in a mixed landscape consisting of urban and agro-forested areas and forest fragments in Malaysia. We collected a total of 5570 and 4029 of feeding records for M. fascicularis and T. o. obscurus, respectively, using the 10-min scan sampling method. Food availability and seasonal changes in plant species consumed by both study groups were determined by vegetation surveys carried out across an area of 1.6 ha. A total of 113 and 130 plant species were consumed by M. fascicularis and T. o. obscurus, respectively. Leaves (51%) and fruits (40%) accounted for the majority of the feeding records in T. o. obscurus, whereas fruits (32%) and anthropogenic foods (27%) together with leaves (15%) and insects (6%) accounted for the majority of the feeding records for M. fascicularis. Throughout the year, there were 59 consumed plant species common to both species, and the dietary overlap was the highest for fruits. Although leaves were always more abundant than fruits in our study site, the amount of monthly fruit eating by the two species showed a significant correlation with that of fruit availability. Monthly fruit availability had a positive effect on overall monthly dietary overlap while flower and leaf availability had a negative effect. We showed that fruit was the preferred food resource of two sympatric species with different digestive systems. This could have implications for resource competition, interspecific competition, and niche separation, which should be investigated in more detail.
    Matched MeSH terms: Macaca fascicularis/physiology*; Colobinae/physiology*
  2. Mohamed Elias Z, Batumalai UM, Azmi ANH
    Appl Ergon, 2019 Nov;81:102879.
    PMID: 31422241 DOI: 10.1016/j.apergo.2019.102879
    Increasing popularity of virtual reality (VR) gaming is causing increased concern, as prolonged use induces visual adaptation effects which disturbs normal vision. Effects of VR gaming on accommodation and convergence of young adults by measuring accommodative response and phoria before and after experiencing virtual reality were measured. An increase in accommodative response and a decrease in convergence was observed after immersion in VR games. It was found that visual symptoms were apparent among the subjects post VR exposure.
    Matched MeSH terms: Accommodation, Ocular/physiology*; Convergence, Ocular/physiology*
  3. Singh VA, Ramalingam S, Haseeb A, Yasin NFB
    J Orthop Surg (Hong Kong), 2020 7 23;28(2):2309499020941659.
    PMID: 32696708 DOI: 10.1177/2309499020941659
    INTRODUCTION: Limb length discrepancy (LLD) of lower extremities is underdiagnosed due to compensatory mechanisms during locomotion. The natural course of compensation leads to biomechanical alteration in human musculoskeletal system leading to adverse effects. General consensus accepts LLD more than 2 cm as significant to cause biomechanical alteration. No studies were conducted correlating height and lower extremities true length (TL) to signify LLD. Examining significant LLD in relation to height and TL using dynamic gait analysis with primary focus on kinematics and secondary focus on kinetics would provide an objective evaluation method.

    METHODOLOGY: Forty participants with no evidence of LLD were recruited. Height and TL were measured. Reflective markers were attached at specific points in lower extremity and subjects walked in gait lab at a self-selected normal walking pace with artificial LLDs of 0, 1, 2, 3, and 4 cm simulated using shoe raise. Accommodation period of 30 min was given. Infrared cameras were used to capture the motion. Primary kinematic (knee flexion and pelvic obliquity (PO)) and secondary kinetic (ground reaction force (GRF)) were measured at right heel strike and left heel strike. Functional adaptation was analyzed and the postulated predictor indices (PIs) were used as a screening tool using height, LLD, and TL to notify significance.

    RESULTS: There was a significant knee flexion component seen in height category of less than 170 cm. There was significant difference between LLD 3 cm and 4 cm. No significant changes were seen in PO and GRF. PIs of LLD/height and LLD/TL were analyzed using receiver operating characteristic curve. LLD/height as a PI with value of 1.75 was determined with specificity of 80% and sensitivity of 76%.

    CONCLUSION: A height of less than 170 cm has significant changes in relation to LLD. PI using LLD/height appears to be a promising tool to identify patients at risk.

    Matched MeSH terms: Gait/physiology*; Walking/physiology*
  4. Kassim NF, Webb CE, Russell RC
    J Am Mosq Control Assoc, 2012 Dec;28(4):312-6.
    PMID: 23393755
    Culex molestus is an obligatory autogenous mosquito that is closely associated with subterranean habitats in urban areas. The objective of our study was to investigate the influence of larval and adult nutrition on the role of males in determining the expression of autogeny in Cx. molestus. Mosquitoes raised at low and high larval diets had sex ratio, wing length, mating rates, autogenous egg raft size, and hatching rates recorded. There was a higher ratio of males to females when raised at a low larval diet. Mean wing lengths of both males and females were significantly greater when raised at the high larval diet regime. Regardless of larval or adult diet, males mated with only a single female. Mosquitoes raised at the higher larval diet regimes developed significantly more autogenous eggs. However, the egg raft size was reduced when adult females were denied access to sugar. The results of this study indicate that the performance of males in the reproductive process is influenced by both larval diet and adult sugar feeding.
    Matched MeSH terms: Culex/physiology*; Larva/physiology
  5. Yong MH, Lim XL, Schaefer A
    Neurosci Lett, 2020 02 16;720:134759.
    PMID: 31952988 DOI: 10.1016/j.neulet.2020.134759
    Past research has found that several brain event-related potentials (ERPs) were sensitive to the perception of ethnic differences displayed on human faces. This body of research suggests that the phenomenon of "race perception" involves a cascade of cognitive processes that includes both automatic and overt attentional mechanisms. However, most of these studies used stimuli depicting whole faces rather than stimuli depicting separate facial features. Therefore, it is still largely unknown if ERP responses to racial differences are the result of a holistic processing of the whole face, or whether they can be accounted for by the perception of single facial features. To address this issue, we examined whether a single facial feature, the eyes region, can provide sufficient information to trigger known ERP correlates of race perception such as the P2, the N400 and the Late Positive Complex (LPC). Specifically, we showed pictures depicting only the eyes region of Caucasian and Asian faces to a sample of Asian participants. We found that the P2 was larger for other-race (OR) compared to same-race (SR) eyes, and that the N400 was larger for SR compared to OR eyes. The effects on the P2 may suggest an enhanced vigilance response to OR eyes whereas the N400 effect could reflect a signal of familiarity triggered by SR eyes. These results indicate that a specific facial feature, the eyes region, can account for known effects of race perception on early brain potentials. Our findings also indicate that well-known early neural correlates of race perception can be triggered in the absence of a holistic processing of the whole face.
    Matched MeSH terms: Facial Recognition/physiology*; Brain/physiology*
  6. Yeang HY
    New Phytol, 2007;175(2):283-9.
    PMID: 17587376
    How tropical trees flower synchronously near the equator in the absence of significant day length variation or other meteorological cues has long been a puzzle. The rubber tree (Hevea brasiliensis) is used as a model to investigate this phenomenon. The annual cycle of solar radiation intensity is shown to correspond closely with the flowering of the rubber tree planted near the equator and in the subtropics. Unlike in temperate regions, where incoming solar radiation (insolation) is dependent on both day length and radiation intensity, insolation at the equator is due entirely to the latter. Insolation at the upper atmosphere peaks twice a year during the spring and autumn equinoxes, but the actual solar radiation that reaches the ground is attenuated to varying extents in different localities. The rubber tree shows one or two flowering seasons a year (with major and minor seasons in the latter) in accordance with the solar radiation intensity received. High solar radiation intensity, and in particular bright sunshine (as distinct from prolonged diffuse radiation), induces synchronous anthesis and blooming in Hevea around the time of the equinoxes. The same mechanism may be operational in other tropical tree species.
    Matched MeSH terms: Hevea/physiology*; Flowers/physiology*
  7. Yeang HY
    New Phytol, 2007;176(4):730-5.
    PMID: 17997756
    Matched MeSH terms: Hevea/physiology*; Flowers/physiology*
  8. Tee HS, Lee CY
    J Insect Physiol, 2015 Jun;77:45-54.
    PMID: 25921676 DOI: 10.1016/j.jinsphys.2015.04.007
    The impact of desiccation on habitat selection, foraging and survival has been characterized for many insects. However, limited information is available for parasitic wasps. In this study, water balance, relative humidity (RH) preference, and effect of humidity on survival of solitary Evania appendigaster (L.) (Hymenoptera: Evaniidae) and gregarious Aprostocetus hagenowii (Ratzeburg) (Hymenoptera: Eulophidae) were examined. These species are both oothecal parasitoids of the American cockroach Periplaneta americana (L.) (Dictyoptera: Blattidae). E. appendigaster had significantly higher cuticular permeability (CP) and a lower surface area to volume ratio but a similar percentage of total body water content compared to A. hagenowii. No differences in these attributes were found between sexes of each parasitoid species. The percentage of total body water loss rates among E. appendigaster males and females and A. hagenowii females were similar but significantly lower than that of A. hagenowii males. All parasitoids except E. appendigaster males exhibited reduced survival times as the RH of their enclosure decreased from 87% to 38%, but this phenomenon did not occur when parasitoids were given a sugar solution. In environmental chambers with a 44-87% RH gradient, both sexes of E. appendigaster resided significantly more often in the 87% RH chamber than in the 44% RH chamber. For A. hagenowii, females preferred both the driest and the wettest chambers and males preferred the driest ones. These results demonstrate the water balance profile and its relationship to life history traits and differential responses to RH in these competing parasitoid wasps, suggesting the role of physiological and behavioral adaptations in shaping their ecological niche.
    Matched MeSH terms: Wasps/physiology*; Water-Electrolyte Balance/physiology*
  9. Thonis A, Ceballos RM, Tuen AA, Lovegrove BG, Levesque DL
    Physiol Biochem Zool, 2020 3 21;93(3):199-209.
    PMID: 32196407 DOI: 10.1086/708467
    Tropical ectotherms are generally believed to be more vulnerable to global heating than temperate species. Currently, however, we have insufficient knowledge of the thermoregulatory physiology of equatorial tropical mammals, particularly of small diurnal mammals, to enable similar predictions. In this study, we measured the resting metabolic rates (via oxygen consumption) of wild-caught lesser treeshrews (Tupaia minor, order Scandentia) over a range of ambient temperatures. We predicted that, similar to other treeshrews, T. minor would exhibit more flexibility in body temperature regulation and a wider thermoneutral zone compared with other small mammals because these thermoregulatory traits provide both energy and water savings at high ambient temperatures. Basal metabolic rate was on average

    1.03
    ±
    0.10

    mL O2 h-1 g-1, which is within the range predicted for a 65-g mammal. We calculated the lower critical temperature of the thermoneutral zone at 31.0°C (95% confidence interval: 29.3°-32.7°C), but using metabolic rates alone, we could not determine the upper critical temperature at ambient temperatures as high as 36°C. The thermoregulatory characteristics of lesser treeshrews provide a means of saving energy and water at temperatures well in excess of their current environmental temperatures. Our research highlights the knowledge gaps in our understanding of the energetics of mammals living in high-temperature environments, specifically in the equatorial tropics, and questions the purported lack of variance in the upper critical temperatures of the thermoneutral zone in mammals, emphasizing the importance of further research in the tropics.
    Matched MeSH terms: Body Temperature Regulation/physiology*; Tupaia/physiology*
  10. Abdullah RB, Liow SL, Rahman AN, Chan WK, Wan-Khadijah WE, Ng SC
    Theriogenology, 2008 Sep 15;70(5):765-71.
    PMID: 18579196 DOI: 10.1016/j.theriogenology.2008.04.052
    The objective was to evaluate the effect of the interval between ovarian hyperstimulation and laparoscopic ovum pick-up (LOPU) on quality and developmental competence of goat oocytes before and after in vitro maturation (IVM) and intracytoplasmic sperm injection (ICSI). Estrus was synchronized with an intravaginal insert containing 0.3g progesterone (CIDR) for 10d, combined with a luteolytic treatment of 125 microg cloprostenol 36 h prior to CIDR removal. Ovaries were hyperstimulated with 70 mg FSH and 500 IU hCG given im 36, 60, or 72 h prior to LOPU (n=15, 16, and 7 does, respectively). For these groups, oocyte retrieval rates (mean+/-S.E.M.) were 24.7+/-2.9, 54.5+/-4.7, and 82.8+/-4.6% (P<0.001), and the proportions of cumulus-oocyte complexes (COC) with more than five layers of cumulus cells were 29.7+/-8.3, 37.6+/-6.9, and 37.3+/-7.0% (P<0.001). The proportion of IVM oocytes was highest at 72 h (82.1+/-2.8%; P<0.05), with no significant difference between 36 and 60 h (57.3+/-8.9% and 69.0+/-8.4%). Cleavage rates of ICSI embryos were 4.2+/-4.2, 70.9+/-8.4, and 78.9+/-8.2% with LOPU 36, 60, and 72 h post FSH/hCG (P<0.01), with a lower proportion of Grade-A embryos (P<0.05) following LOPU at 36 h compared to 60 and 72 h (29.7+/-8.3%, 37.6+/-6.9%, and 37.3+/-7.0%). In summary, a prolonged interval from FSH/hCG to LOPU improved oocyte retrieval rate and oocyte quality. Therefore, under the present conditions, LOPU 60 or 72 h after FSH/hCG optimized yields of good-quality oocytes for IVM and embryo production in goats.
    Matched MeSH terms: Goats/physiology*; Ovum/physiology*
  11. Maryam S, Fadzly N, Amirul AA, Zuharah WF
    Rev Inst Med Trop Sao Paulo, 2017 Apr 03;59:e4.
    PMID: 28380115 DOI: 10.1590/S1678-9946201759004
    Paederus fuscipes, a vector of Paederus dermatitis in most tropical and subtropical countries of the world have a high prevalence in human dwellings due to their positively phototaxic behaviour which has caused a tremendous impact on human health. In this paper, P. fuscipes dispersal flights were studied for two seasons of the rice cultivation phases in residential premises built close to rice field areas (≈32-60 m and 164 m) in mainland Penang, Malaysia. We examined the effects of different light illuminance, building floor level and their association with rice stages as a focal cause of P. fuscipes dispersion from the rice fields towards human dwellings. The present study showed a significant interaction between different light illuminances and rice cultivation phases in attracting P. fuscipes to disperse and invade human dwellings. The highest number of P. fuscipes was captured near the bright light. P. fuscipes flights increased in line with each floor level, and the highest captures took place at higher building floor levels (levels 2 and 3) compared to lower building floor levels (ground floor and level 1) of a three storey apartment in both rice seasons. This finding not only conveys a better understanding on P. fuscipes dispersal pattern, but also draws public attention on the occurrence of dermatitis linearis caused by the Paederus beetles.
    Matched MeSH terms: Beetles/physiology*; Behavior, Animal/physiology*
  12. Malik IA, Durairajanayagam D, Singh HJ
    Asian J Androl, 2018 12 13;21(3):296-299.
    PMID: 30539926 DOI: 10.4103/aja.aja_98_18
    Leptin, an adipocyte-derived hormone, serves numerous physiological functions in the body, particularly during puberty and reproduction. The exact mechanism by which leptin activates the gonadotropin-releasing hormone (GnRH) neurons to trigger puberty and reproduction remains unclear. Given the widespread distribution of leptin receptors in the body, both central and peripheral mechanisms involving the hypothalamic-pituitary-gonadal axis have been hypothesized. Leptin is necessary for normal reproductive function, but when present in excess, it can have detrimental effects on the male reproductive system. Human and animal studies point to leptin as a link between infertility and obesity, a suggestion that is corroborated by findings of low sperm count, increased sperm abnormalities, oxidative stress, and increased leptin levels in obese men. In addition, daily leptin administration to normal-weight rats has been shown to result in similar abnormalities in sperm parameters. The major pathways causing these abnormalities remain unidentified; however, these adverse effects have been attributed to leptin-induced increased oxidative stress because they are prevented by concurrently administering melatonin. Studies on leptin and its impact on sperm function are highly relevant in understanding and managing male infertility, particularly in overweight and obese men.
    Matched MeSH terms: Reproduction/physiology*; Leptin/physiology*
  13. Thomas AG, Jonason PK, Blackburn JD, Kennair LEO, Lowe R, Malouff J, et al.
    J Pers, 2020 06;88(3):606-620.
    PMID: 31494937 DOI: 10.1111/jopy.12514
    OBJECTIVE: Mate choice involves trading-off several preferences. Research on this process tends to examine mate preference prioritization in homogenous samples using a small number of traits and thus provide little insight into whether prioritization patterns reflect a universal human nature. This study examined whether prioritization patterns, and their accompanying sex differences, are consistent across Eastern and Western cultures.

    METHOD: In the largest test of the mate preference priority model to date, we asked an international sample of participants (N = 2,477) to design an ideal long-term partner by allocating mate dollars to eight traits using three budgets. Unlike previous versions of the task, we included traits known to vary in importance by culture (e.g., religiosity and chastity).

    RESULTS: Under low budget conditions, Eastern and Western participants differed in their mate dollar allocation for almost every trait (average d = 0.42), indicating that culture influences prioritization. Despite these differences, traits fundamental for the reproductive success of each sex in the ancestral environment were prioritized by both Eastern and Western participants.

    CONCLUSION: The tendency to prioritize reproductively fundamental traits is present in both Eastern and Western cultures. The psychological mechanisms responsible for this process produce similar prioritization patterns despite cross-cultural variation.

    Matched MeSH terms: Choice Behavior/physiology*; Personality/physiology*
  14. Muhamad HM, Xu X, Zhang X, Jaaman SA, Muda AM
    J Acoust Soc Am, 2018 05;143(5):2708.
    PMID: 29857727 DOI: 10.1121/1.5036926
    Studies of Irrawaddy dolphins' acoustics assist in understanding the behaviour of the species and thereby conservation of this species. Whistle signals emitted by Irrawaddy dolphin within the Bay of Brunei in Malaysian waters were characterized. A total of 199 whistles were analysed from seven sightings between January and April 2016. Six types of whistles contours named constant, upsweep, downsweep, concave, convex, and sine were detected when the dolphins engaged in traveling, foraging, and socializing activities. The whistle durations ranged between 0.06 and 3.86 s. The minimum frequency recorded was 443 Hz [Mean = 6000 Hz, standard deviation (SD) = 2320 Hz] and the maximum frequency recorded was 16 071 Hz (Mean = 7139 Hz, SD = 2522 Hz). The mean frequency range (F.R.) for the whistles was 1148 Hz (Minimum F.R. = 0 Hz, Maximum F.R. = 4446 Hz; SD = 876 Hz). Whistles in the Bay of Brunei were compared with population recorded from the waters of Matang and Kalimantan. The comparisons showed differences in whistle duration, minimum frequency, start frequency, and number of inflection point. Variation in whistle occurrence and frequency may be associated with surface behaviour, ambient noise, and recording limitation. This will be an important element when planning a monitoring program.
    Matched MeSH terms: Dolphins/physiology*; Vocalization, Animal/physiology*
  15. Dong L, Caruso F, Lin M, Liu M, Gong Z, Dong J, et al.
    J Acoust Soc Am, 2019 06;145(6):3289.
    PMID: 31255103 DOI: 10.1121/1.5110304
    Whistles emitted by Indo-Pacific humpback dolphins in Zhanjiang waters, China, were collected by using autonomous acoustic recorders. A total of 529 whistles with clear contours and signal-to-noise ratio higher than 10 dB were extracted for analysis. The fundamental frequencies and durations of analyzed whistles were in ranges of 1785-21 675 Hz and 30-1973 ms, respectively. Six tonal types were identified: constant, downsweep, upsweep, concave, convex, and sine whistles. Constant type was the most dominant tonal type, accounting for 32.51% of all whistles, followed by sine type, accounting for 19.66% of all whistles. This paper examined 17 whistle parameters, which showed significant differences among the six tonal types. Whistles without inflections, gaps, and stairs accounted for 62.6%, 80.6%, and 68.6% of all whistles, respectively. Significant intraspecific differences in all duration and frequency parameters of dolphin whistles were found between this study and the study in Malaysia. Except for start frequency, maximum frequency and the number of harmonics, all whistle parameters showed significant differences between this study and the study conducted in Sanniang Bay, China. The intraspecific differences in vocalizations for this species may be related to macro-geographic and/or environmental variations among waters, suggesting a potential geographic isolation among populations of Indo-Pacific humpback dolphins.
    Matched MeSH terms: Dolphins/physiology*; Vocalization, Animal/physiology*
  16. Sharifat H, Suppiah S
    Med J Malaysia, 2021 05;76(3):401-413.
    PMID: 34031341
    INTRODUCTION: Internet Addiction Disorder (IAD) is an umbrella term for various types of Internet-based behavioural addiction, whereas Internet Gaming Disorder (IGD) addresses a specific type of IAD that is postulated to be due to a lack of control in impulse inhibition. IGD is an area of concern in the Diagnostic and Statistics Manual of Mental Disorders (DSM-5), which can be objectively assessed by dysfunctional behaviour and the increasing time of being online, particularly during the COVID-19 pandemic. Electroencephalography (EEG) identifies amplitude changes in the evoked response potential (ERP) among IGDs, correlated with underlying comorbidities.

    MATERIALS AND METHODS: A scoping review was performed to elaborate on the research regarding resting-state EEG and task-based EEG, particularly for Go/No-go paradigms pertaining to subjects with IAD or specifically IGD. The role of EEG was identified in its diagnostic capability to identify the salient changes that occurred in the response to reward network and the executive control network, using restingstate and task-based EEG. The implication of using EEG in monitoring the therapy for IAD and IGD was also reviewed.

    RESULTS: EEG generally revealed reduced beta waves and increased theta waves in addicts. IGD with depression demonstrated increased theta and decreased alpha waves. Whereas increased P300, a late cognitive ERP component, was frequently associated with impaired excessive allocation of attentional resources of the IAD towards addiction-specific cues. IGD had increased whole brain delta waves at baseline, which showed significant reduction post therapy.

    CONCLUSION: EEG can identify distinct neurophysiological changes among Internet Addiction Disorder and Internet Gaming Disorder that are akin to substance abuse disorders.

    Matched MeSH terms: Attention/physiology*; Executive Function/physiology*
  17. Alam MZ, Fakhru'l-Razi A
    Water Res, 2003 Mar;37(5):1118-24.
    PMID: 12553987
    A study was conducted to evaluate the settleability and dewaterability of fungal treated and untreated sludge using liquid state bioconversion process. The fungal mixed culture of Aspergillus niger and Penicillium corylophilum was used for fungal pretreatment of wastewater sludge. The fungal strains immobilized/entrapped on sludge particles with the formation of pellets and enhanced the separation process. The results presented in this study showed that the sludge particles (pellets) size of 2-5mm of diameter were formed with the microbial treatment of sludge after 2 days of fermentation that contained maximum 33.7% of total particles with 3-3.5mm of diameter. The settling rate (measured as total suspended solids (TSS) concentration, 130 mg/l) was faster in treated sludge than untreated sludge (TSS concentration, 440 mg/l) after 1 min of settling time. In 1 min of settling operation, 86.45% of TSS was settled in treated sludge while 4.35% of TSS settled in raw sludge. Lower turbidity was observed in treated sludge as compared to untreated sludge. The results to specific resistance to filtration (SRF) revealed that the fungal inoculum had significant potentiality to reduce SRF by 99.8% and 98.7% for 1% w/w and 4% w/w of TSS sludge, respectively. The optimum fermentation period recorded was 3 days for 1% w/w sludge and 6 days for 4% w/w sludge, respectively, for dewaterability test.
    Matched MeSH terms: Aspergillus niger/physiology*; Penicillium/physiology*
  18. Tuma J, Eggleton P, Fayle TM
    Biol Rev Camb Philos Soc, 2020 06;95(3):555-572.
    PMID: 31876057 DOI: 10.1111/brv.12577
    Animal interactions play an important role in understanding ecological processes. The nature and intensity of these interactions can shape the impacts of organisms on their environment. Because ants and termites, with their high biomass and range of ecological functions, have considerable effects on their environment, the interaction between them is important for ecosystem processes. Although the manner in which ants and termites interact is becoming increasingly well studied, there has been no synthesis to date of the available literature. Here we review and synthesise all existing literature on ant-termite interactions. We infer that ant predation on termites is the most important, most widespread, and most studied type of interaction. Predatory ant species can regulate termite populations and subsequently slow down the decomposition of wood, litter and soil organic matter. As a consequence they also affect plant growth and distribution, nutrient cycling and nutrient availability. Although some ant species are specialised termite predators, there is probably a high level of opportunistic predation by generalist ant species, and hence their impact on ecosystem processes that termites are known to provide varies at the species level. The most fruitful future research direction will be to evaluate the impact of ant-termite predation on broader ecosystem processes. To do this it will be necessary to quantify the efficacy both of particular ant species and of ant communities as a whole in regulating termite populations in different biomes. We envisage that this work will require a combination of methods, including DNA barcoding of ant gut contents along with field observations and exclusion experiments. Such a combined approach is necessary for assessing how this interaction influences entire ecosystems.
    Matched MeSH terms: Ants/physiology*; Isoptera/physiology*
  19. Omar Farouk FN, Stott D, Vlad M
    Anim Sci J, 2011 Jun;82(3):420-7.
    PMID: 21615835 DOI: 10.1111/j.1740-0929.2010.00869.x
    This study was conducted to examine the potential for implantation and sustainable fetal development of mouse embryos cultured from the pronuclear to blastocyst stage. Pronuclear embryos from ICR mice (Harlan Sprague-Dawley) were cultured in Sydney IVF sequential media (Cook) to the blastocyst stage in medium only or co-cultured with autologous cumulus cells. We also experimented with co-culture in 100 µL drops. Drop co-culture produced blastocyst formation rates with a mean of 47.0%, which was significantly higher (P < 0.05) compared to embryos cultured in identical culture conditions except without cumulus cells at 27.3%. Blastocysts obtained in vitro in Cook medium only and co-cultured in Cook medium with cumulus cells were transferred to pseudopregnant females of ICR strain. The day of blastocyst transfer into surrogate females was designated as post-transfer of blastocyst day 1 (PT 1). The implantation and fetal development was compared to embryo transfer of in vivo derived blastocysts, which served as controls. There were no statistical differences for implantation and fetal development rates for blastocysts cultured in vitro in either Cook medium only or co-culture in Cook medium with cumulus cells compared to in vivo-derived blastocysts. The advantage of the co-culture system is in generating more blastocysts available for transfer.
    Matched MeSH terms: Blastocyst/physiology; Fetal Development/physiology*
  20. Neoh KB, Lee CY
    J Insect Sci, 2011;11:47.
    PMID: 21861651 DOI: 10.1673/031.011.4701
    The larval parasitoid Verticia fasciventris Malloch (Diptera: Calliphoridae) develops in the head of soldiers of the fungus-growing termite Macrotermes carbonarius (Hagen) (Isoptera: Termitidae). Morphological and behavioral changes in the host were evaluated and the termite castes and stages that were parasitized were identified. The larval emergence process is also described and possible mechanisms for the parasitoid fly's entry into the host body are discussed based on qualitative observations. Only a single larva per host was found. The mature larva pupated outside the host's body by exiting between the abdominal cerci. Parasitized soldiers possess a short and square-shaped head capsule, a pair of notably short mandibles, and a pair of 18-segmented antennae. Although parasitized soldiers were statistically less aggressive than healthy soldiers (P < 0.05), they expressed varying levels of aggression. Both minor and major soldiers can be parasitized and based on evidence from presoldiers, parasitization may begin during the precursor stages of soldiers. However, the stage at which parasitism first occurs has not been determined.
    Matched MeSH terms: Diptera/physiology*; Larva/physiology
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