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A short note on seed dispersal by colobines: the case of the proboscis monkey

Matsuda I, Higashi S, Otani Y, Tuuga A, Bernard H, Corlett RT

Integr Zool, 2013 Dec;8(4):395-9.
PMID: 24344963 DOI: 10.1111/1749-4877.12033

Although the role of primates in seed dispersal is generally well recognized, this is not the case for colobines, which are widely distributed in Asian and African tropical forests. Colobines consume leaves, seeds and fruits, usually unripe. A group of proboscis monkeys (Colobinae, Nasalis larvatus) consisting of 1 alpha-male, 6 adult females and several immatures, was observed from May 2005 to May 2006. A total of 400 fecal samples from focal group members covering 13 months were examined, with over 3500 h of focal observation data on the group members in a forest along the Menanggul River, Sabah, Malaysia. Intact small seeds were only found in 23 of 71 samples in Nov 2005, 15 of 38 in Dec 2005 and 5 of 21 in Mar 2006. Seeds of Ficus (all <1.5 mm in length) were found in all 3 months and seeds from Antidesma thwaitesianum (all <3 mm) and Nauclea subdita (all <2 mm) only in Nov and Dec, which was consistent with members of the study group consuming fruits of these species mostly at these times. To our knowledge, these are the first records of seeds in the fecal samples of colobines. Even if colobines pass relatively few seeds intact, their high abundance and biomass could make them quantitatively significant in seed dispersal. The potential role of colobines as seed dispersers should be considered by colobine researchers.

Matched MeSH terms: Colobinae/physiology*; Seed Dispersal/physiology*
Fulltext Influence of age on patellar tendon reflex response

Chandrasekhar A, Abu Osman NA, Tham LK, Lim KS, Wan Abas WA

PLoS One, 2013;8(11):e80799.
PMID: 24260483 DOI: 10.1371/journal.pone.0080799

BACKGROUND: A clinical parameter commonly used to assess the neurological status of an individual is the tendon reflex response. However, the clinical method of evaluation often leads to subjective conclusions that may differ between examiners. Moreover, attempts to quantify the reflex response, especially in older age groups, have produced inconsistent results. This study aims to examine the influence of age on the magnitude of the patellar tendon reflex response.
METHODOLOGY/PRINCIPAL FINDINGS: This study was conducted using the motion analysis technique with the reflex responses measured in terms of knee angles. Forty healthy subjects were selected and categorized into three different age groups. Patellar reflexes were elicited from both the left and right patellar tendons of each subject at three different tapping angles and using the Jendrassik maneuver. The findings suggested that age has a significant effect on the magnitude of the reflex response. An angle of 45° may be the ideal tapping angle at which the reflex can be elicited to detect age-related differences in reflex response. The reflex responses were also not influenced by gender and were observed to be fairly symmetrical.
CONCLUSIONS/SIGNIFICANCE: Neurologically normal individuals will experience an age-dependent decline in patellar reflex response.

Matched MeSH terms: Reflex, Stretch/physiology*; Patellar Ligament/physiology*
Fulltext Naive Bayes-guided bat algorithm for feature selection

Taha AM, Mustapha A, Chen SD

ScientificWorldJournal, 2013;2013:325973.
PMID: 24396295 DOI: 10.1155/2013/325973

When the amount of data and information is said to double in every 20 months or so, feature selection has become highly important and beneficial. Further improvements in feature selection will positively affect a wide array of applications in fields such as pattern recognition, machine learning, or signal processing. Bio-inspired method called Bat Algorithm hybridized with a Naive Bayes classifier has been presented in this work. The performance of the proposed feature selection algorithm was investigated using twelve benchmark datasets from different domains and was compared to three other well-known feature selection algorithms. Discussion focused on four perspectives: number of features, classification accuracy, stability, and feature generalization. The results showed that BANB significantly outperformed other algorithms in selecting lower number of features, hence removing irrelevant, redundant, or noisy features while maintaining the classification accuracy. BANB is also proven to be more stable than other methods and is capable of producing more general feature subsets.

Matched MeSH terms: Chiroptera/physiology*; Echolocation/physiology*
Fulltext Balance control in lower extremity amputees during quiet standing: a systematic review

Ku PX, Abu Osman NA, Wan Abas WA

Gait Posture, 2014 Feb;39(2):672-82.
PMID: 24331296 DOI: 10.1016/j.gaitpost.2013.07.006

Postural control has been widely evaluated for the normal population and different groups over the past 20 years. Numerous studies have investigated postural control in quiet standing posture among amputees. However, a comprehensive analysis is lacking on the possible contributing factors to balance. The present systematic review highlights the current findings on variables that contribute to balance instability for lower extremity amputees. The search strategy was performed on PubMed, Web of Science, Medline, Scopus, and CINAHL and then followed by additional manual searching via reference lists in the reviewed articles. The quality of the articles was evaluated using a methodological quality assessment tool. This review included and evaluated a total of 23 full-text articles. Despite the inconsistencies in the methodological design of the studies, all articles scored above the acceptable level in terms of quality. A majority of the studies revealed that lower extremity amputees have increased postural sway in the standing posture. Asymmetry in body weight, which is mainly distributed in the non-amputated leg, was described. Aside from the centre of pressure in postural control, sensory inputs may be a related topic for investigation in view of evidence on their contribution, particularly visual input. Other balance-related factors, such as stump length and patients' confidence level, were also neglected. Further research requires examination on the potential factors that affect postural control as the information of standing postural is still limited.

Matched MeSH terms: Postural Balance/physiology*; Posture/physiology*
Fulltext Review of emotion recognition in stroke patients

Yuvaraj R, Murugappan M, Norlinah MI, Sundaraj K, Khairiyah M

Dement Geriatr Cogn Disord, 2013;36(3-4):179-96.
PMID: 23899462 DOI: 10.1159/000353440

OBJECTIVE: Patients suffering from stroke have a diminished ability to recognize emotions. This paper presents a review of neuropsychological studies that investigated the basic emotion processing deficits involved in individuals with interhemispheric brain (right, left) damage and normal controls, including processing mode (perception) and communication channels (facial, prosodic-intonational, lexical-verbal).
METHODS: An electronic search was conducted using specific keywords for studies investigating emotion recognition in brain damage patients. The PubMed database was searched until March 2012 as well as citations and reference lists. 92 potential articles were identified.
RESULTS: The findings showed that deficits in emotion perception were more frequently observed in individuals with right brain damage than those with left brain damage when processing facial, prosodic and lexical emotional stimuli.
CONCLUSION: These findings suggest that the right hemisphere has a unique contribution in emotional processing and provide support for the right hemisphere emotion hypothesis.
SIGNIFICANCE:
This robust deficit in emotion recognition has clinical significance. The extent of emotion recognition deficit in brain damage patients appears to be correlated with a variety of interpersonal difficulties such as complaints of frustration in social relations, feelings of social discomfort, desire to connect with others, feelings of social disconnection and use of controlling behaviors.

Matched MeSH terms: Emotions/physiology*; Recognition (Psychology)/physiology*
Influential factors in stability of lower-limb amputees

Kamali M, Karimi MT, Eshraghi A, Omar H

Am J Phys Med Rehabil, 2013 Dec;92(12):1110-8.
PMID: 23900009 DOI: 10.1097/PHM.0b013e31829b4b7a

Lower-limb amputation is mainly a result of trauma, vascular disease, diabetes, or congenital disorders. Persons with amputation lose their ability to stand and walk on the basis of the level of amputation. Contribution of level of amputation, type of amputation, or cause of amputation to balance impairment has not been clearly defined. Furthermore, it is controversial how much the mentioned parameters influence standing stability. Therefore, the aim of this review article was to find the relationship between the abovementioned factors and balance impairment in the available literature. It was also aimed to find the possibility of improving standing stability by the use of different prosthesis components.

Matched MeSH terms: Postural Balance/physiology*; Walking/physiology*
Reduced cannibalistic behavior of African catfish, Clarias gariepinus, larvae under dark and dim conditions

Mukai Y, Sanudin N, Firdaus RF, Saad S

Zoolog Sci, 2013 Jun;30(6):421-4.
PMID: 23721464 DOI: 10.2108/zsj.30.421

In general, African catfish shows higher survival rates in the dark conditions than in the light conditions. In this study, larval behavior of African catfish was observed under 0, 0.01, 0.1, 1, 10, and 100 lx using a CCD camera to investigate the reason why African catfish larvae show higher survival rates in dark conditions. The larvae showed significantly higher swimming activity under 0, 0.01, and 0.1 lx than that under 10 and 100 lx. The larvae also showed significantly increased aggressive behavior under 10 and 100 lx; the swimming larvae attacked resting individuals more frequently under 10 and 100 lx than under 0, 0.01, and 0.1 lx. The aggressive behavior and sharp teeth of the attacking larvae appeared to induce skin surface lesions on injured larvae. Chemical substances were then generated from the injured skin surface, and these chemical stimuli triggered cannibalistic behavior in other fish near the injured fish. The results of this study demonstrate that the higher survival rates of African catfish larvae under dark conditions are a result of inactivity and subsequent increase in chemical releasing stimuli concentrations around inactive individuals that triggers feeding behavior in nearby active catfish. Therefore, we recommend larval rearing of African catfish in dark or dim conditions, as it improves catfish survival rates.

Matched MeSH terms: Catfishes/physiology*; Larva/physiology
Biomechanical evaluation of the relationship between postural control and body mass index

Ku PX, Abu Osman NA, Yusof A, Wan Abas WA

J Biomech, 2012 Jun 1;45(9):1638-42.
PMID: 22507349 DOI: 10.1016/j.jbiomech.2012.03.029

Postural stability is crucial in maintaining body balance during quiet standing, locomotion, and any activities that require a high degree of balance performance, such as participating in sports and dancing. Research has shown that there is a relationship between stability and body mass. The aims of this study were to examine the impact that two variables had on static postural control: body mass index (BMI) and gender. Eighty healthy young adults (age=21.7±1.8 yr; height=1.65±0.09 m; mass=67.5±19.0 kg) participated in the study and the static postural control was assessed using the Biodex Balance System, with a 20 Hz sampling rate in the bipedic stance (BLS) and unipedic stance (ULS) for 30s. Five test evaluations were performed for each balance test. Postural control was found to be negatively correlated with increased adiposity, as the obese BMI group performed significantly poorer than the underweight, normal weight and overweight groups during BLS and ULS tests. The underweight, normal weight and overweight groups exhibited greater anterior-posterior stability in postural control during quiet stance. In addition, female displayed a trend of having a greater postural sway than male young adults, although it was evidenced in only some BMI groups. This study revealed that BMI do have an impact on postural control during both BLS and ULS. As such, BMI and gender-specific effects should be taken into consideration when selecting individuals for different types of sporting activities, especially those that require quiet standing.

Matched MeSH terms: Postural Balance/physiology*; Posture/physiology*
Vocal fold vibratory characteristics in normal female speakers from high-speed digital imaging

Ahmad K, Yan Y, Bless DM

J Voice, 2012 Mar;26(2):239-53.
PMID: 21621975 DOI: 10.1016/j.jvoice.2011.02.001

The purpose of the study was to investigate relationships between vocal fold vibrations and voice quality. Laryngeal images obtained from high-speed digital imaging (HSDI) were examined for their open-closed timing characteristics and perturbation values. A customized software delineated the glottal edges and used the Hilbert transform-based method of analysis to provide objective quantification of glottal perturbation. Overlay tracings of the transformed glottal cycles provided visual patterns on the overall vibratory dynamics. In this paper, we described the use of this method in looking at vibratory characteristics of a group of young female speakers (N=23). We found that, females with no voice complaints and who had been perceived to have normal voices were not a homogeneous group in terms of their glottal vibratory patterns during phonation. Their vibratory patterns showed characteristics similar to exemplar voices targeted to be clear (50%), pressed (27%), breathy (15%), or a mixed quality (8%). Perturbation range in terms of cycle-to-cycle frequency and amplitude was small and did not discriminate patterns. All these patterns yielded perceptually normal voices suggesting that in normal young speakers, the level of perturbation may be more important to the judgment than the actual pattern of closure.

Matched MeSH terms: Speech/physiology; Vocal Cords/physiology*
Population ecology and movement of the American cockroach (Dictyoptera: Blattidae) in sewers

Tee HS, Saad AR, Lee CY

J Med Entomol, 2011 Jul;48(4):797-805.
PMID: 21845938

The population size, age-class structure, and movement of the American cockroach, Periplaneta americana (L.) (Dictyoptera: Blattidae), were studied in three sewers in Penang, Malaysia, from September 2008 to October 2009. Eighteen to 20 glass-jar traps (two per manhole) were deployed for a 24-h period during each sampling occasion at each sewer. Adults and nymphs were active throughout the study period, with an average monthly trap catch of 57-97 adults and 79-99 nymphs. The mean proportions of adults and nymphs at the three sewers ranged from 0.47 to 0.57. Of the 2177 male and 2717 female cockroaches marked and released over the three sewers, recapture rates were 29.4-45.8 and 30.8-47.0%, respectively. The proportion of marked males and females did not differ significantly from the proportion of recaptured marked males and females. However, the mean number of times a marked female was recaptured was significantly greater than that of males. Of the 783 males and 1,030 females that were marked and recaptured, 19.4 and 24.7%, respectively, had moved between manholes, and significantly more females than males moved between manholes. Of the 406 recaptured marked adults that moved between manholes, 90.4% moved a distance of 2-20 m from their initial release site; one male moved 192 m, the longest distance recorded. Trap catch on each sampling occasion was positively correlated with daily mean temperature. The number of cockroach movements between manholes also was correlated with the mean daily minimum temperature.

Matched MeSH terms: Nymph/physiology; Periplaneta/physiology*
Fulltext A large-scale forest fragmentation experiment: the Stability of Altered Forest Ecosystems Project

Ewers RM, Didham RK, Fahrig L, Ferraz G, Hector A, Holt RD, et al.

Philos Trans R Soc Lond B Biol Sci, 2011 Nov 27;366(1582):3292-302.
PMID: 22006969 DOI: 10.1098/rstb.2011.0049

Opportunities to conduct large-scale field experiments are rare, but provide a unique opportunity to reveal the complex processes that operate within natural ecosystems. Here, we review the design of existing, large-scale forest fragmentation experiments. Based on this review, we develop a design for the Stability of Altered Forest Ecosystems (SAFE) Project, a new forest fragmentation experiment to be located in the lowland tropical forests of Borneo (Sabah, Malaysia). The SAFE Project represents an advance on existing experiments in that it: (i) allows discrimination of the effects of landscape-level forest cover from patch-level processes; (ii) is designed to facilitate the unification of a wide range of data types on ecological patterns and processes that operate over a wide range of spatial scales; (iii) has greater replication than existing experiments; (iv) incorporates an experimental manipulation of riparian corridors; and (v) embeds the experimentally fragmented landscape within a wider gradient of land-use intensity than do existing projects. The SAFE Project represents an opportunity for ecologists across disciplines to participate in a large initiative designed to generate a broad understanding of the ecological impacts of tropical forest modification.

Matched MeSH terms: Trees/physiology*; Arecaceae/physiology
Differentiation and adaptive radiation of amphibious gobies (Gobiidae: Oxudercinae) in semi-terrestrial habitats

Polgar G, Sacchetti A, Galli P

J Fish Biol, 2010 Nov;77(7):1645-64.
PMID: 21078024 DOI: 10.1111/j.1095-8649.2010.02807.x

During several surveys made in the region of the lower Fly River and delta, Papua New Guinea, nine species of oxudercine gobies (Gobiidae: Oxudercinae) were recorded: Boleophthalmus caeruleomaculatus, Oxuderces wirzi, Periophthalmodon freycineti, Periophthalmus darwini, Periophthalmus novaeguineaensis, Periophthalmus takita, Periophthalmus weberi, Scartelaos histophorus and Zappa confluentus. An exploratory multivariate analysis of their habitat conditions discriminated five guilds, differentially distributed in habitats with different quantities of environmental water and three guilds corresponding to different levels of salinity. A partial correspondence between phylogenetic and ecological categories suggested the presence of parallel adaptive radiations within different genera. In particular, the species found in the most terrestrial habitats (P. weberi) was also found in the widest range of conditions, suggesting that colonization of extreme semi-terrestrial and freshwater habitats by this species was facilitated by eurytypy. It is proposed that these findings provide insight into convergent adaptations for the vertebrate eco-evolutionary transition from sea to land.

Matched MeSH terms: Adaptation, Physiological/physiology*; Perciformes/physiology*
Functional uniqueness of a small carnivore as seed dispersal agents: a case study of the common palm civets in the Tabin Wildlife Reserve, Sabah, Malaysia

Nakashima Y, Inoue E, Inoue-Murayama M, Abd Sukor JR

Oecologia, 2010 Nov;164(3):721-30.
PMID: 20602116 DOI: 10.1007/s00442-010-1714-1

Many carnivorous mammals consume fruits and disperse the intact seeds to specific sites. Few studies have attempted to quantify this seed dispersal or evaluate its effectiveness, despite its potential importance and functional uniqueness. In the study reported here, we found that a frugivorous carnivore, the common palm civet (Paradoxurus hermaphroditus), generated seed shadows that are distinct from those of the sympatric frugivore, the pig-tailed macaque (Macaca nemestrina), and played a unique and important role in the regeneration of Leea aculeata (Leeaceae). We found that macaques dispersed the seeds randomly, while civets dispersed them non-randomly to sites such as the banks of small rivers, rain-flow paths, abandoned trails, and treefall gaps, which are characterized by low stem density and canopy cover. Seeds of L. aculeata that were dispersed by civets to the banks of rivers and gaps had significantly higher survival and growth rates than those dispersed to rain-flow paths or abandoned trails. Seeds dispersed by macaques or to random locations also had low survival. Although the effects of the civets on seed fate were not straightforward, compared with macaques and random dispersal, civets significantly enhanced the survival and growth of L. aculeata seeds after 1 year. These results indicate that non-random dispersal by civets is important for the persistence of L. aculeata. Civets may disperse other plant species and thus could have profound effects on forest dynamics.

Matched MeSH terms: Macaca nemestrina/physiology*; Viverridae/physiology*
Experimental investigation of the flow of bile in patient specific cystic duct models

Al-Atabi M, Chin SB, Luo XY

J Biomech Eng, 2010 Apr;132(4):041003.
PMID: 20387966 DOI: 10.1115/1.4001043

Three-dimensional scaled-up transparent models of three human cystic ducts were prepared on the basis of anatomical specimens. The measurement of pressure drop across the cystic duct models and visualization of the flow structures within these ducts were performed at conditions replicating the physiological state. The flow visualization study confirmed the laminar nature of the flow of bile inside the cystic duct and values of pressure drop coefficient (Cp) decreased as the Reynolds number (Re) increased. The three tested models showed comparable behavior for the curve of Reynolds number versus the pressure drop coefficient. The results show that the tested cystic ducts have both increased pressure drop and complicated flow structures when compared with straight conduits. High resistance in a cystic duct may indicate that the gallbladder has to exert large force in expelling bile to the cystic duct. For patients with diseased gallbladder, and even in healthy persons, gallbladder is known to stiffen with age and it may lose its compliance or flexibility. A high resistance cystic duct coupled with a stiffened gallbladder may result in prolonged stasis of bile in the gallbladder, which is assumed to encourage the formation of gallstones.

Matched MeSH terms: Bile/physiology*; Cystic Duct/physiology*
Spizaetus hawk-eagles as predators of arboreal colobines

Fam SD, Nijman V

Primates, 2011 Apr;52(2):105-10.
PMID: 21340695 DOI: 10.1007/s10329-011-0240-z

The predation pressure put on primates by diurnal birds of prey differs greatly between continents. Africa and South America have specialist raptors (e.g. crowned hawk-eagle Stephanoaetus coronatus and harpy eagle Harpia harpyja) whereas in Asia the only such specialist's (Philippine eagle Pithecophaga jefferyi) distribution is largely allopatric with primates. The almost universal absence of polyspecific groups in Asia (common in Africa and South America) may indicate reduced predation pressure. As such there is almost no information on predation pressures on primates in Asia by raptors. Here we report successful predation of a juvenile banded langur Presbytis femoralis (~2 kg) by a changeable hawk-eagle Spizaetus cirrhatus. The troop that was attacked displayed no signs of being alarmed, and no calls were made before the event. We argue that in insular Southeast Asia, especially, large Spizaetus hawk-eagles (~2 kg) are significant predators of arboreal colobines. Using data on the relative size of sympatric Spizaetus hawk-eagles and colobines we make predictions on where geographically we can expect the highest predation pressure (Thai-Malay Peninsula) and which colobines are least (Nasalis larvatus, Trachypithecus auratus, P. thomasi) and most (P. femoralis, T. cristatus) affected.

Matched MeSH terms: Colobinae/physiology*; Eagles/physiology*
Current status and prospective application of stem cell-based therapies for spinal cord injury

Das AK, Gopurappilly R, Parhar I

Curr Stem Cell Res Ther, 2011 Jun;6(2):93-104.
PMID: 21190537

Spinal cord injuries (SCIs) are a common form of trauma that leaves a huge trail of morbidity and human suffering in its wake. They occur mostly among the young, causing severe physical, psychological, social and economic burdens. The treatment of this condition has rather been disappointing; most of the management strategies being mainly supportive and prophylactic. In recent years there has been an emerging interest in the use of stem cells to regenerate the nervous tissue that has been damaged or lost. Although there has been much hype and unfounded hope, modest successes have been witnessed, and it is possible that these therapeutic strategies may have much more to offer in the future. This paper will review the current strategies of exploring cell-based therapies, mainly different types of stem cells to treat SCI along with the evidence that has been accumulated over the past decade in a rational bench-to-bedside approach. Furthermore, critical aspects such as the mode of delivery and ethical considerations are also discussed along with feasible suggestions for future translational research to provide a contextual picture of the current state of advancements in this field. The impediments to regeneration in the site of injury are briefly explained along with the benefits and drawbacks of different cell types used in the treatment of this condition. We hope that this review will offer a significant insight into this challenging clinical condition.

Matched MeSH terms: Nerve Regeneration/physiology*; Stem Cells/physiology*
Feeding ecology of Bornean orangutans (Pongo pygmaeus morio) in Danum Valley, Sabah, Malaysia: a 3-year record including two mast fruitings

Kanamori T, Kuze N, Bernard H, Malim TP, Kohshima S

Am J Primatol, 2010 Sep;72(9):820-40.
PMID: 20653008 DOI: 10.1002/ajp.20848

We observed the diet and activity of Bornean orangutans (Pongo pygmaeus morio) in the primary lowland dipterocarp forests of Danum Valley, Sabah, Malaysia, during 2005-2007, including two mast fruitings. We collected 1,785 hr of focal data on 26 orangutans. We identified 1,466 samples of their food plants and conducted a fallen fruit census to monitor fruit availability in the study area. Their activity budget was 47.2% feeding, 34.4% resting, and 16.9% traveling. Fruits accounted for the largest part (60.9%) of feeding time, especially during mast fruiting periods (64.0-100%), although the percentages of leaves (22.2%) and bark (12.3%) were higher than those reported for P. abelii and P. pygmaeus wurmbii. Although 119 genera and 160 plant species were consumed by focal animals, only 9 genera accounted for more than 3% of feeding time (total: 67.8% for 9 genera). In particular, the focal orangutans fed intensively on Ficus and Spatholobus during most of the study period, especially in periods of fruit shortage. The percentage of fruit feeding changed markedly from 11.7 to 100% across different months of the year, and was positively correlated with the amount of fallen fruit. When fruit feeding and availability decreased, orangutans fed primarily on leaves of Spatholobus and Ficus, and the bark of Spatholobus and dipterocarp. The percentage of time devoted to feeding during mast fruitings, when the orangutans foraged almost exclusively on fruits, was lower than during seasons when the orangutan diet included leaves and bark as well as fruits. Resting increased as feeding decreased in the late stage of each fruiting season, suggesting that the orangutans adopted an energy-minimizing strategy to survive the periods of fruit shortage by using energy stored during the fruit season.

Matched MeSH terms: Feeding Behavior/physiology*; Pongo pygmaeus/physiology*
Behavioral and morphological changes in soldiers of Macrotermes gilvus (Termitidae: Macrotermitinae) parasitized by Misotermes mindeni (Diptera: Phoridae)

Neoh KB, Lee CY

Environ Entomol, 2010 Jun;39(3):835-40.
PMID: 20550796 DOI: 10.1603/EN09212

Misotermes mindeni Disney and Neoh is a solitary endoparasitoid of Macrotermes gilvus (Hagen) (Termitidae: Macrotermitinae), exclusively parasitizing the head of major soldiers. In this study, behavioral and morphological changes in the parasitized termite host were evaluated. We also observed the larval parasitoid emerging from the host. We found that parasitism mainly occurred in termite mounds overgrown with grass and mounds that had been broken up previously for other experiments. The parasitized soldiers showed a significantly lower level of interspecific aggressiveness compared with healthy soldiers (P < 0.05). Parasitized soldiers also changed in habitat preference to one isolated chamber of the nest. This might be an adaptive strategy that facilitates parasitoid dispersal, provides protection to parasitoids, and reduces the risk of parasitism to host colony. An abnormally rounded head capsule and remarkably short mandibles are characteristics of a parasitized soldier. The older larval fly stages were found only in major soldiers. We suggest that parasitization may first start in fourth or even earlier larval termite instars. The fly larva develops in the termite soldier's head capsule and pupates inside the host's body.

Matched MeSH terms: Diptera/physiology*; Larva/physiology
Ileal endogenous amino acid flow of broiler chickens under high ambient temperature

Soleimani AF, Kasim A, Alimon AR, Meimandipour A, Zulkifli I

J Anim Physiol Anim Nutr (Berl), 2010 Oct;94(5):641-7.
PMID: 20050954 DOI: 10.1111/j.1439-0396.2009.00951.x

High environmental temperature has detrimental effects on the gastrointestinal tract of poultry. An experiment was conducted to determine the effect of acute heat stress on endogenous amino acid (EAA) flow in broiler chickens. A total of 90, day-old broiler chicks were housed in battery cages in an environmentally controlled chamber. Chicks were fed a nitrogen-free diet on day 42 following either no heat exposure (no-heat) or 2 weeks exposure to 35 ± 1 °C for 3 h from days 28 to 42 (2-week heat) or 1 week exposure to 35 ± 1 °C for 3 h from days 35 to 42 (1 week heat). The most abundant amino acid in the ileal flow was glutamic acid, followed by aspartic acid, serine and threonine in non-heat stressed group. The EAA flow in 1-week heat and 2-week heat birds were significantly (p < 0.05) higher than those under no heat exposure (14682, 11161 and 9597 mg/kg of dry matter intake respectively). Moreover, the EAA flow of 2-week heat group was less than 1-week heat group by approximately 36%. These observations suggest that the effect of heat stress on EAA flow is mostly quantitative; however, heat stress may also alter the content of EAA flow qualitatively.

Matched MeSH terms: Acclimatization/physiology; Chickens/physiology*
Model-based neuroimaging for cognitive computing

Poznanski RR

J Integr Neurosci, 2009 Sep;8(3):345-69.
PMID: 19938210

The continuity of the mind is suggested to mean the continuous spatiotemporal dynamics arising from the electrochemical signature of the neocortex: (i) globally through volume transmission in the gray matter as fields of neural activity, and (ii) locally through extrasynaptic signaling between fine distal dendrites of cortical neurons. If the continuity of dynamical systems across spatiotemporal scales defines a stream of consciousness then intentional metarepresentations as templates of dynamic continuity allow qualia to be semantically mapped during neuroimaging of specific cognitive tasks. When interfaced with a computer, such model-based neuroimaging requiring new mathematics of the brain will begin to decipher higher cognitive operations not possible with existing brain-machine interfaces.

Matched MeSH terms: Brain/physiology*; Cognition/physiology*

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