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  1. Homeobox genes and tooth development: Understanding the biological pathways and applications in regenerative dental science
    Ramanathan A, Srijaya TC, Sukumaran P, Zain RB, Abu Kasim NH
    Arch Oral Biol, 2018 Jan;85:23-39.
    PMID: 29031235 DOI: 10.1016/j.archoralbio.2017.09.033
    OBJECTIVES: Homeobox genes are a group of conserved class of transcription factors that function as key regulators during the embryonic developmental processes. They act as master regulator for developmental genes, which involves coordinated actions of various auto and cross-regulatory mechanisms. In this review, we summarize the expression pattern of homeobox genes in relation to the tooth development and various signaling pathways or molecules contributing to the specific actions of these genes in the regulation of odontogenesis.

    MATERIALS AND METHODS: An electronic search was undertaken using combination of keywords e.g. Homeobox genes, tooth development, dental diseases, stem cells, induced pluripotent stem cells, gene control region was used as search terms in PubMed and Web of Science and relevant full text articles and abstract were retrieved that were written in English. A manual hand search in text books were also carried out. Articles related to homeobox genes in dentistry and tissue engineering and regenerative medicine of odontogenesis were selected.

    RESULTS: The possible perspective of stem cells technology in odontogenesis and subsequent analysis of gene correction pertaining to dental disorders through the possibility of induced pluripotent stem cells technology is also inferred.

    CONCLUSIONS: We demonstrate the promising role of tissue engineering and regenerative medicine on odontogenesis, which can generate a new ray of hope in the field of dental science.

    Matched MeSH terms: Genes, Homeobox/physiology*; Stem Cells/physiology*
  2. Animacy-Based Accessibility and Competition in Relative Clause Production in Hindi and Malayalam
    Perera CK, Srivastava AK
    J Psycholinguist Res, 2016 Aug;45(4):915-30.
    PMID: 26108301 DOI: 10.1007/s10936-015-9384-0
    Two studies investigated interaction of animacy-based accessibility and competition processes with language specific constraints in shaping production preferences. Relative clause elicitation tasks (Gennari et al. in Cogn Psychol 65:141-176, 2012) were performed by two groups with 40 participants in each. Significantly more passives were produced with animate question/focus and assigned subject function to them in Malayalam, while the difference was insignificant in Hindi with animacy not equating with grammatical function assignment. Both languages produced active objects with OSV order significantly more with animate question/focus. This indicates animacy effect on word order. Animacy also influenced the expression of the agent phase in both languages as a tendency was found to omit the agent by-phase or to delay its appearance, when the two animate nouns entering into the structure are highly similar. The results point to language specific constraints in relative clause production and variability in the role of animacy-based retrieval order across languages.
    Matched MeSH terms: Pattern Recognition, Visual/physiology*; Speech/physiology*
  3. Fulltext Induced mitochondrial membrane potential for modeling solitonic conduction of electrotonic signals
    Poznanski RR, Cacha LA, Ali J, Rizvi ZH, Yupapin P, Salleh SH, et al.
    PLoS One, 2017;12(9):e0183677.
    PMID: 28880876 DOI: 10.1371/journal.pone.0183677
    A cable model that includes polarization-induced capacitive current is derived for modeling the solitonic conduction of electrotonic potentials in neuronal branchlets with microstructure containing endoplasmic membranes. A solution of the nonlinear cable equation modified for fissured intracellular medium with a source term representing charge 'soakage' is used to show how intracellular capacitive effects of bound electrical charges within mitochondrial membranes can influence electrotonic signals expressed as solitary waves. The elastic collision resulting from a head-on collision of two solitary waves results in localized and non-dispersing electrical solitons created by the nonlinearity of the source term. It has been shown that solitons in neurons with mitochondrial membrane and quasi-electrostatic interactions of charges held by the microstructure (i.e., charge 'soakage') have a slower velocity of propagation compared with solitons in neurons with microstructure, but without endoplasmic membranes. When the equilibrium potential is a small deviation from rest, the nonohmic conductance acts as a leaky channel and the solitons are small compared when the equilibrium potential is large and the outer mitochondrial membrane acts as an amplifier, boosting the amplitude of the endogenously generated solitons. These findings demonstrate a functional role of quasi-electrostatic interactions of bound electrical charges held by microstructure for sustaining solitons with robust self-regulation in their amplitude through changes in the mitochondrial membrane equilibrium potential. The implication of our results indicate that a phenomenological description of ionic current can be successfully modeled with displacement current in Maxwell's equations as a conduction process involving quasi-electrostatic interactions without the inclusion of diffusive current. This is the first study in which solitonic conduction of electrotonic potentials are generated by polarization-induced capacitive current in microstructure and nonohmic mitochondrial membrane current.
    Matched MeSH terms: Action Potentials/physiology*; Neurons/physiology*
  4. Resistance of tropical seedlings to drought is mediated by neighbourhood diversity
    O'Brien MJ, Reynolds G, Ong R, Hector A
    Nat Ecol Evol, 2017 Nov;1(11):1643-1648.
    PMID: 28963453 DOI: 10.1038/s41559-017-0326-0
    Occasional periods of drought are typical of most tropical forests, but climate change is increasing drought frequency and intensity in many areas across the globe, threatening the structure and function of these ecosystems. The effects of intermittent drought on tropical tree communities remain poorly understood and the potential impacts of intensified drought under future climatic conditions are even less well known. The response of forests to altered precipitation will be determined by the tolerances of different species to reduced water availability and the interactions among plants that alleviate or exacerbate the effects of drought. Here, we report the response of experimental monocultures and mixtures of tropical trees to simulated drought, which reveals a fundamental shift in the nature of interactions among species. Weaker competition for water in diverse communities allowed seedlings to maintain growth under drought while more intense competition among conspecifics inhibited growth under the same conditions. These results show that reduced competition for water among species in mixtures mediates community resistance to drought. The delayed onset of competition for water among species in more diverse neighbourhoods during drought has potential implications for the coexistence of species in tropical forests and the resilience of these systems to climate change.
    Matched MeSH terms: Trees/physiology*; Seedlings/physiology
  5. Chlorogenic acids and the acyl-quinic acids: discovery, biosynthesis, bioavailability and bioactivity
    Clifford MN, Jaganath IB, Ludwig IA, Crozier A
    Nat Prod Rep, 2017 Dec 13;34(12):1391-1421.
    PMID: 29160894 DOI: 10.1039/c7np00030h
    Covering: 2000 up to late 2017This review is focussed upon the acyl-quinic acids, the most studied group within the ca. 400 chlorogenic acids so far reported. The acyl-quinic acids, the first of which was characterised in 1846, are a diverse group of plant-derived compounds produced principally through esterification of an hydroxycinnamic acid and 1l-(-)-quinic acid. Topics addressed in this review include the confusing nomenclature, quantification and characterisation by NMR and MS, biosynthesis and role in planta, and the occurrence of acyl-quinic acids in coffee, their transformation during roasting and delivery to the beverage. Coffee is the major human dietary source world-wide of acyl-quinic acids and consideration is given to their absorption and metabolism in the upper gastrointestinal tract, and the colon where the microbiota play a key role in the formation of catabolites. Evidence on the potential of the in vivo metabolites and catabolites of acyl-quinic acids to promote the consumer's health is evaluated.
    Matched MeSH terms: Coffee/physiology; Microbiota/physiology
  6. In Vitro Evaluation of Human Hand Tendon Ingrowth into A Synthetic Scaffold
    Abdullah S, Mohtar F, Abdul Shukor N, Sapuan J
    J Hand Surg Asian Pac Vol, 2017 Dec;22(4):429-434.
    PMID: 29117830 DOI: 10.1142/S0218810417500459
    BACKGROUND: Synthetic scaffold has been used for tissue approximation and reconstructing damaged and torn ligaments. This study explores the ability of tendon ingrowth into a synthetic scaffold in vitro, evaluate growth characteristics, morphology and deposition of collagen matrix into a synthetic scaffold.

    METHODS: Upper limb tendons were harvested with consent from patients with crush injuries and non-replantable amputations. These tendons (both extensor and flexor) measuring 1 cm are sutured to either side of a 0.5 cm synthetic tendon strip and cultured in growth medium. At 2, 4, 6 and 8 weeks, samples were fixed into paraffin blocks, cut and stained with haematoxylin-eosin (H&E) and Masson's trichrome.

    RESULTS: Minimal tendon ingrowth were seen in the first 2 weeks of incubation. However at 4 weeks, the cell ingrowth were seen migrating towards the junction between the tendon and the synthetic scaffold. This ingrowth continued to expand at 6 weeks and up to 8 weeks. At this point, the demarcation between human tendon and synthetic scaffold was indistinct.

    CONCLUSIONS: We conclude that tendon ingrowth composed of collagen matrix were able to proliferate into a synthetic scaffold in vitro.

    Matched MeSH terms: Regeneration/physiology*; Tendons/physiology*
  7. The effect of 10 days of intermittent fasting on Wingate anaerobic power and prolonged high-intensity time-to-exhaustion cycling performance
    Naharudin MNB, Yusof A
    Eur J Sport Sci, 2018 Jun;18(5):667-676.
    PMID: 29485326 DOI: 10.1080/17461391.2018.1438520
    Many physically active individuals have undertaken intermittent fasting to reduce their daily caloric intake. However, abstaining from meals for a specific length of time may lead to the acute disturbance of highly carbohydrate-dependent exercise performance. The purpose of this study was to observe the effect of 10 days of intermittent fasting on high-intensity type exercises, Wingate anaerobic (WT) and prolonged high-intensity time-to-exhaustion (HIT) cycling test. Twenty participants were randomised into an intermittent fasting (FAS) and a control group (CON). One day after baseline data collection on Day-0 where participants consumed their recommended daily caloric intake (FAS = 2500 ± 143 kcal day-1; CON = 2492 ± 20 kcal day-1) served over a course of five meals, the FAS group consumed only four meals where 40% was restricted by the omission of lunch (FAS = 1500 ± 55 kcal day-1). This diet was then continued for 10 days. Data on exercise performance and other dependent variables were collected on Day-2, -4, -6, -8 and -10. A reduction in WT power in the FAS group was observed on Day-2 (821.74 ± 66.07 W) compared to Day-0 (847.63 ± 95.94 W) with a moderate effect size (p 
    Matched MeSH terms: Exercise/physiology*; Athletic Performance/physiology*
  8. Fulltext Overview of the Microenvironment of Vasculature in Vascular Tone Regulation
    Loh YC, Tan CS, Ch'ng YS, Yeap ZQ, Ng CH, Yam MF
    Int J Mol Sci, 2018 Jan 02;19(1).
    PMID: 29301280 DOI: 10.3390/ijms19010120
    Hypertension is asymptomatic and a well-known "silent killer", which can cause various concomitant diseases in human population after years of adherence. Although there are varieties of synthetic antihypertensive drugs available in current market, their relatively low efficacies and major application in only single drug therapy, as well as the undesired chronic adverse effects associated, has drawn the attention of worldwide scientists. According to the trend of antihypertensive drug evolution, the antihypertensive drugs used as primary treatment often change from time-to-time with the purpose of achieving the targeted blood pressure range. One of the major concerns that need to be accounted for here is that the signaling mechanism pathways involved in the vasculature during the vascular tone regulation should be clearly understood during the pharmacological research of antihypertensive drugs, either in vitro or in vivo. There are plenty of articles that discussed the signaling mechanism pathways mediated in vascular tone in isolated fragments instead of a whole comprehensive image. Therefore, the present review aims to summarize previous published vasculature-related studies and provide an overall depiction of each pathway including endothelium-derived relaxing factors, G-protein-coupled, enzyme-linked, and channel-linked receptors that occurred in the microenvironment of vasculature with a full schematic diagram on the ways their signals interact. Furthermore, the crucial vasodilative receptors that should be included in the mechanisms of actions study on vasodilatory effects of test compounds were suggested in the present review as well.
    Matched MeSH terms: Blood Vessels/physiology*; Endothelium, Vascular/physiology
  9. Pathogenesis of microbial keratitis
    Lakhundi S, Siddiqui R, Khan NA
    Microb Pathog, 2017 Mar;104:97-109.
    PMID: 27998732 DOI: 10.1016/j.micpath.2016.12.013
    Microbial keratitis is a sight-threatening ocular infection caused by bacteria, fungi, and protist pathogens. Epithelial defects and injuries are key predisposing factors making the eye susceptible to corneal pathogens. Among bacterial pathogens, the most common agents responsible for keratitis include Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pneumonia and Serratia species. Fungal agents of corneal infections include both filamentous as well as yeast, including Fusarium, Aspergillus, Phaeohyphomycetes, Curvularia, Paecilomyces, Scedosporium and Candida species, while in protists, Acanthamoeba spp. are responsible for causing ocular disease. Clinical features include redness, pain, tearing, blur vision and inflammation but symptoms vary depending on the causative agent. The underlying molecular mechanisms associated with microbial pathogenesis include virulence factors as well as the host factors that aid in the progression of keratitis, resulting in damage to the ocular tissue. The treatment therefore should focus not only on the elimination of the culprit but also on the neutralization of virulence factors to minimize the damage, in addition to repairing the damaged tissue. A complete understanding of the pathogenesis of microbial keratitis will lead to the rational development of therapeutic interventions. This is a timely review of our current understanding of the advances made in this field in a comprehensible manner. Coupled with the recently available genome sequence information and high throughput genomics technology, and the availability of innovative approaches, this will stimulate interest in this field.
    Matched MeSH terms: Acanthamoeba/physiology; Fungi/physiology
  10. Fulltext Robust EEG/MEG Based Functional Connectivity with the Envelope of the Imaginary Coherence: Sensor Space Analysis
    Sanchez Bornot JM, Wong-Lin K, Ahmad AL, Prasad G
    Brain Topogr, 2018 11;31(6):895-916.
    PMID: 29546509 DOI: 10.1007/s10548-018-0640-0
    The brain's functional connectivity (FC) estimated at sensor level from electromagnetic (EEG/MEG) signals can provide quick and useful information towards understanding cognition and brain disorders. Volume conduction (VC) is a fundamental issue in FC analysis due to the effects of instantaneous correlations. FC methods based on the imaginary part of the coherence (iCOH) of any two signals are readily robust to VC effects, but neglecting the real part of the coherence leads to negligible FC when the processes are truly connected but with zero or π-phase (modulus 2π) interaction. We ameliorate this issue by proposing a novel method that implements an envelope of the imaginary coherence (EIC) to approximate the coherence estimate of supposedly active underlying sources. We compare EIC with state-of-the-art FC measures that included lagged coherence, iCOH, phase lag index (PLI) and weighted PLI (wPLI), using bivariate autoregressive and stochastic neural mass models. Additionally, we create realistic simulations where three and five regions were mapped on a template cortical surface and synthetic MEG signals were obtained after computing the electromagnetic leadfield. With this simulation and comparison study, we also demonstrate the feasibility of sensor FC analysis using receiver operating curve analysis whilst varying the signal's noise level. However, these results should be interpreted with caution given the known limitations of the sensor-based FC approach. Overall, we found that EIC and iCOH demonstrate superior results with most accurate FC maps. As they complement each other in different scenarios, that will be important to study normal and diseased brain activity.
    Matched MeSH terms: Brain/physiology*; Neural Pathways/physiology
  11. Advancement of Electrospun Nerve Conduit for Peripheral Nerve Regeneration: A Systematic Review (2016-2021)
    Lee SY, Thow SY, Abdullah S, Ng MH, Mohamed Haflah NH
    Int J Nanomedicine, 2022;17:6723-6758.
    PMID: 36600878 DOI: 10.2147/IJN.S362144
    Peripheral nerve injury (PNI) is a worldwide problem which hugely affects the quality of patients' life. Nerve conduits are now the alternative for treatment of PNI to mimic the gold standard, autologous nerve graft. In that case, with the advantages of electrospun micro- or nano-fibers nerve conduit, the peripheral nerve growth can be escalated, in a better way. In this systematic review, we focused on 39 preclinical studies of electrospun nerve conduit, which include the in vitro and in vivo evaluation from animal peripheral nerve defect models, to provide an update on the progress of the development of electrospun nerve conduit over the last 5 years (2016-2021). The physical characteristics, biocompatibility, functional and morphological outcomes of nerve conduits from different studies would be compared, to give a better strategy for treatment of PNI.
    Matched MeSH terms: Nerve Regeneration/physiology; Sciatic Nerve/physiology
  12. A robust real-time gait event detection using wireless gyroscope and its application on normal and altered gaits
    Gouwanda D, Gopalai AA
    Med Eng Phys, 2015 Feb;37(2):219-25.
    PMID: 25619613 DOI: 10.1016/j.medengphy.2014.12.004
    Gait events detection allows clinicians and biomechanics researchers to determine timing of gait events, to estimate duration of stance phase and swing phase and to segment gait data. It also aids biomedical engineers to improve the design of orthoses and FES (functional electrical stimulation) systems. In recent years, researchers have resorted to using gyroscopes to determine heel-strike (HS) and toe-off (TO) events in gait cycles. However, these methods are subjected to significant delays when implemented in real-time gait monitoring devices, orthoses, and FES systems. Therefore, the work presented in this paper proposes a method that addresses these delays, to ensure real-time gait event detection. The proposed algorithm combines the use of heuristics and zero-crossing method to identify HS and TO. Experiments involving: (1) normal walking; (2) walking with knee brace; and (3) walking with ankle brace for overground walking and treadmill walking were designed to verify and validate the identified HS and TO. The performance of the proposed method was compared against the established gait detection algorithms. It was observed that the proposed method produced detection rate that was comparable to earlier reported methods and recorded reduced time delays, at an average of 100 ms.
    Matched MeSH terms: Ankle/physiology; Knee/physiology
  13. Aquatic biomonitoring of Giardia cysts and Cryptosporidium oocysts in peninsular Malaysia
    Lee SC, Ngui R, Tan TK, Roslan MA, Ithoi I, Lim YA
    Environ Sci Pollut Res Int, 2014 Jan;21(1):445-53.
    PMID: 23794081 DOI: 10.1007/s11356-013-1925-1
    An aquatic biomonitoring of Giardia cysts and Cryptosporidium oocysts in river water corresponding to five villages situated in three states in peninsular Malaysia was determined. There were 51.3% (20/39) and 23.1% (9/39) samples positive for Giardia and Cryptosporidium (oo)cysts, respectively. Overall mean concentration between villages for Giardia cysts ranged from 0.10 to 25.80 cysts/l whilst Cryptosporidium oocysts ranged from 0.10 to 0.90 oocysts/l. Detailed results of the river samples from five villages indicated that Kuala Pangsun 100% (9/9), Kemensah 77.8% (7/9), Pos Piah 33.3% (3/9) and Paya Lebar 33.3% (1/3) were contaminated with Giardia cysts whilst Cryptosporidium (oo)cysts were only detected in Kemensah (100 %; 9/9) and Kuala Pangsun (66.6%; 6/9). However, the water samples from Bentong were all negative for these waterborne parasites. Samples were collected from lower point, midpoint and upper point. Midpoint refers to the section of the river where the studied communities are highly populated. Meanwhile, the position of the lower point is at least 2 km southward of the midpoint and upper point is at least 2 km northward of the midpoint. The highest mean concentration for (oo)cysts was found at the lower points [3.15 ± 6.09 (oo)cysts/l], followed by midpoints [0.66 ± 1.10 (oo)cysts/l] and upper points [0.66 ± 0.92 (oo)cysts/l]. The mean concentration of Giardia cysts was highest at Kuala Pangsun (i.e. 5.97 ± 7.0 cysts/l), followed by Kemensah (0.83 ± 0.81 cysts/l), Pos Piah (0.20 ± 0.35 cysts/l) and Paya Lebar (0.10 ± 0.19 cysts/l). On the other hand, the mean concentration of Cryptosporidium oocysts was higher at Kemensah (0.31 ± 0.19 cysts/l) compared to Kuala Pangsun (0.03 ± 0.03cysts/l). All the physical and chemical parameters did not show significant correlation with both protozoa. In future, viability status and molecular characterisation of Giardia and Cryptosporidium should be applied to identify species and genotypes/subgenotypes for better understanding of the epidemiology of these waterborne parasites.
    Matched MeSH terms: Cryptosporidium/physiology; Giardia/physiology
  14. Fulltext Influence and implications of the renin-angiotensin-aldosterone system in obstructive sleep apnea: An updated systematic review and meta-analysis
    Loh HH, Lim QH, Chai CS, Goh SL, Lim LL, Yee A, et al.
    J Sleep Res, 2023 Feb;32(1):e13726.
    PMID: 36104933 DOI: 10.1111/jsr.13726
    Obstructive sleep apnea is a chronic, sleep-related breathing disorder, which is an independent risk factor for cardiovascular disease. The renin-angiotensin-aldosterone system regulates salt and water homeostasis, blood pressure, and cardiovascular remodelling. Elevated aldosterone levels are associated with excess morbidity and mortality. We aimed to analyse the influence and implications of renin-angiotensin-aldosterone system derangement in individuals with and without obstructive sleep apnea. We pooled data from 20 relevant studies involving 2828 participants (1554 with obstructive sleep apnea, 1274 without obstructive sleep apnea). The study outcomes were the levels of renin-angiotensin-aldosterone system hormones, blood pressure and heart rate. Patients with obstructive sleep apnea had higher levels of plasma renin activity (pooled wmd+ 0.25 [95% confidence interval 0.04-0.46], p = 0.0219), plasma aldosterone (pooled wmd+ 30.79 [95% confidence interval 1.05-60.53], p = 0.0424), angiotensin II (pooled wmd+ 5.19 [95% confidence interval 3.11-7.27], p 
    Matched MeSH terms: Blood Pressure/physiology; Renin-Angiotensin System/physiology
  15. Effect of coital activity on onset of labor in women scheduled for labor induction: a randomized controlled trial
    Tan PC, Yow CM, Omar SZ
    Obstet Gynecol, 2007 Oct;110(4):820-6.
    PMID: 17906015
    To estimate the effect of coitus on the onset of labor.
    Matched MeSH terms: Coitus/physiology*; Labor Onset/physiology*
  16. Fulltext Draft genome sequence of an Aeromonas sp. strain 159 clinical isolate that shows quorum-sensing activity
    Chan XY, Chua KH, Puthucheary SD, Yin WF, Chan KG
    J Bacteriol, 2012 Nov;194(22):6350.
    PMID: 23105081 DOI: 10.1128/JB.01642-12
    Aeromonas is a pathogenic organism that is often found to infect humans. Here we report the draft genome of a clinical isolate in Malaysia, Aeromonas sp. strain 159, which shows N-acylhomoserine lactone production. In the draft genome of strain 159, luxI and luxR homologue genes were found to be located at contig 47, and these genes are believed to be important for the quorum-sensing system present in this pathogen.
    Matched MeSH terms: Aeromonas/physiology; Quorum Sensing/physiology*
  17. Factors associated with mosquito control among construction workers: A systematic review
    Dapari R, Mohd Fadzil MF, Hanzir MY, Mohamed Jais JS, Safarudin NF, Albar A
    PLoS One, 2024;19(5):e0303330.
    PMID: 38718075 DOI: 10.1371/journal.pone.0303330
    INTRODUCTION: Workers in the construction industry frequently work in construction sites with numerous areas that can potentially accumulate water, such as tanks, wet cement surfaces, or water puddles. These water collection sites become ideal breeding grounds for mosquito infestation, which leads to a higher prevalence of mosquito-borne diseases, especially malaria and dengue among construction workers. Despite that numerous factors have been identified in controlling vector-borne diseases, the specific factors that influence mosquito control at construction sites have yet to be explored.

    AIMS: This systematic review aims to determine the factors associated with mosquito control among construction workers.

    METHODS: Primarily, articles related to factors associated with mosquito control among construction workers were collected from two different online databases (ScienceDirect and EBSCOhost). Two independent reviewers were assigned to screen the titles and abstracts of the collected data, stored in Microsoft Excel, against the inclusion and exclusion criteria. Afterwards, the quality of the included articles was critically assessed using the Mixed Method Appraisal Tool (MMAT). Of the 171 articles identified, 4 were included in the final review.

    RESULTS: Based on the thorough evaluation, mosquito-related knowledge, practical mosquito prevention measures, and Larval Source Management (LSM) were identified as vital factors associated with mosquito control among construction workers. The significant association between mosquito-related knowledge and control practices indicates higher knowledge linked to effective practices, particularly among female workers and those who were recently infected with malaria. Concurrently, there were notable challenges regarding sustainable preventive measures and larval control methods in construction settings.

    CONCLUSION: Implementing effective mosquito control, including knowledge and practice on mosquito control together with vector control, is highly required to suppress the expanding mosquito population. It is recommended that employers provide continuous mosquito control education and training to their employees and reward them with incentives, while employees should comply with the guidelines set by their employers to ensure successful mosquito control and reduce the spread of mosquito-borne diseases in the construction industry.

    Matched MeSH terms: Culicidae/physiology; Mosquito Vectors/physiology
  18. Monitoring of the oestrous cycle in a captive Malayan tapir (Tapirus indicus)
    Schaftenaar W, de Boer AM, Glatston AR
    Vet Rec, 2006 Sep 23;159(13):421-2.
    PMID: 16998001
    Matched MeSH terms: Estrus/physiology*; Perissodactyla/physiology*
  19. Vertical variations in wood CO2 efflux for live emergent trees in a Bornean tropical rainforest
    Katayama A, Kume T, Komatsu H, Ohashi M, Matsumoto K, Ichihashi R, et al.
    Tree Physiol, 2014 May;34(5):503-12.
    PMID: 24876294 DOI: 10.1093/treephys/tpu041
    Difficult access to 40-m-tall emergent trees in tropical rainforests has resulted in a lack of data related to vertical variations in wood CO2 efflux, even though significant variations in wood CO2 efflux are an important source of errors when estimating whole-tree total wood CO2 efflux. This study aimed to clarify vertical variations in wood CO2 efflux for emergent trees and to document the impact of the variations on the whole-tree estimates of stem and branch CO2 efflux. First, we measured wood CO2 efflux and factors related to tree morphology and environment for seven live emergent trees of two dipterocarp species at four to seven heights of up to ∼ 40 m for each tree using ladders and a crane. No systematic tendencies in vertical variations were observed for all the trees. Wood CO2 efflux was not affected by stem and air temperature, stem diameter, stem height or stem growth. The ratios of wood CO2 efflux at the treetop to that at breast height were larger in emergent trees with relatively smaller diameters at breast height. Second, we compared whole-tree stem CO2 efflux estimates using vertical measurements with those based on solely breast height measurements. We found similar whole-tree stem CO2 efflux estimates regardless of the patterns of vertical variations in CO2 efflux because the surface area in the canopy, where wood CO2 efflux often differed from that at breast height, was very small compared with that at low stem heights, resulting in little effect of the vertical variations on the estimate. Additionally, whole-tree branch CO2 efflux estimates using measured wood CO2 efflux in the canopy were considerably different from those measured using only breast height measurements. Uncertainties in wood CO2 efflux in the canopy did not cause any bias in stem CO2 efflux scaling, but affected branch CO2 efflux.
    Matched MeSH terms: Trees/physiology*; Dipterocarpaceae/physiology*
  20. Fulltext Biodiversity, seasonal abundance, and distribution of blackflies (Diptera: Simuliidae) in six different regions of Thailand
    Srisuka W, Takaoka H, Otsuka Y, Fukuda M, Thongsahuan S, Taai K, et al.
    Parasit Vectors, 2017 Nov 21;10(1):574.
    PMID: 29157269 DOI: 10.1186/s13071-017-2492-y
    BACKGROUND: Blackflies are an important medical and veterinary group of small blood-sucking insects. Ninety-three blackfly species have been reported in Thailand. However, information on their biodiversity and population dynamics in each region is lacking. The main aim of this study was to assess the regional biodiversity, seasonal abundance and distribution of blackflies in six eco-geographically different regions in the country.

    METHODS: Blackfly larvae and pupae were sampled monthly from 58 sites between May 2011 and April 2013. Diversity parameters, seasonal abundance, regional distribution and frequency of species occurrence in stream sites were analyzed.

    RESULTS: A total of 19,456 mature larvae representing 57 species, and belonging to six subgenera in the genus Simulium Latreille (s.l.), were found. The five predominant taxa were S. fenestratum (8.6%), the S. asakoae complex (8.3%), S. nakhonense (7.5%), the S. siamense complex (7.4%) and the S. doipuiense complex (6.7%). The most frequent taxa at all sites were the S. asakoae complex (84.5%), followed by S. fenestratum (82.8%), the S. siamense complex (75.9%), S. decuplum (60.3%), S. nakhonense (58.6%) and the S. tani complex (48.3%). The richness of regional species was highest (40 species) in the north and predominated in the cold season. However, blackflies in the south predominated during the hot season. The highest numbers of blackflies collected from central, northeastern, eastern and western regions of the country were observed in the rainy season. Overall, the mean number of blackflies collected across the six regions during the rainy and cold season had no statistically significant difference, but it differed significantly in the hot season.

    CONCLUSIONS: Blackflies in Thailand were surveyed in all three seasons across six geographical regions. These findings demonstrated that blackfly communities at each stream site varied with seasonality, and the regional relative abundance of blackflies differed markedly in the hot season. It was also found that the occurrence and distribution of blackflies in each region were associated strongly with elevation.

    Matched MeSH terms: Larva/physiology; Pupa/physiology
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