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Fulltext Molecular epidemiology of Cryptosporidium in HIV/AIDS patients in Malaysia

Asma I, Sim BL, Brent RD, Johari S, Yvonne Lim AL

Trop Biomed, 2015 Jun;32(2):310-22.
PMID: 26691260 MyJurnal

Cryptosporidiosis is a particular concern in immunocompromised individuals where symptoms may be severe. The aim of this study was to examine the epidemiological and molecular characteristics of Cryptosporidium infections in HIV/AIDS patients in Malaysia in order to identify risk factors and facilitate control measures. A modified Ziehl-Neelsen acid fast staining method was used to test for the presence of Cryptosporidium oocysts in the stools of 346 HIV/AIDS patients in Malaysia. Standard coproscopical methods were used to identify infections with other protozoan or helminths parasites. To identify the species of Cryptosporidium, DNA was extracted and nested-PCR was used to amplify a portion of the SSU rRNA gene. A total of 43 (12.4%) HIV-infected patients were found to be infected with Cryptosporidium spp. Of the 43 Cryptosporidium-positive HIV patients, 10 (23.3%) also harboured other protozoa, and 15 (34.9%) had both protozoa and helminths. The highest rates of cryptosporidiosis were found in adult males of Malay background, intravenous drug users, and those with low CD4 T cell counts (i.e., < 200 cells/mm3). Most were asymptomatic and had concurrent opportunistic infections mainly with Mycobacterium tuberculosis. DNA sequence analysis of 32 Cryptosporidium isolates identified C. parvum (84.3%), C. hominis (6.3%), C. meleagridis (6.3%), and C. felis (3.1%). The results of the present study revealed a high prevalence of Cryptosporidium infection in hospitalized HIV/AIDS patients. The results also confirmed the potential significance of zoonotic transmission of C. parvum in HIV infected patients, as it was the predominant species found in this study. However, these patients were found to be susceptible to a wide range of Cryptosporidium species. Epidemiological and molecular characterization of Cryptosporidium isolates provides clinicians and researchers with further information regarding the origin of the infection, and may enhance treatment and control strategies.
Bioequivalence and pharmacokinetic comparison of two fixed dose combination of Metformin/ Glibenclamide formulations in healthy subjects under fed condition

Chang CT, Ang JY, Wong JM, Tan SS, Chin SK, Lim AB, et al.

Med J Malaysia, 2020 05;75(3):286-291.
PMID: 32467546

AIM: This study is conducted to compare the pharmacokinetic profiles of two fixed dose combination of metformin/glibenclamide tablets (500mg/5 mg per tablet).
MATERIALS AND METHODS: This is a single-center, single-dose, open-label, randomized, 2-treatment, 2-sequence and 2- period crossover study with a washout period of 7 days. All 28 adult male subjects were required to fast for at least 10 hours prior to drug administration and they were given access to water ad libitum during this period. Thirty minutes prior to dosing, all subjects were served with a standardized high-fat and high-calorie breakfast with a total calorie of 1000 kcal which was in accordance to the EMA Guideline on the Investigation of Bioequivalence. Subsequently, subjects were administered either the test or reference preparation with 240mL of plain water in the first trial period. During the second trial period, they received the alternate preparation. Plasma levels of glibenclamide and metformin were analysed separately using two different high performance liquid chromatography methods.
RESULTS: The 90% confidence interval (CI) for the ratio of the AUC0-t, AUC0-∞, and Cmax of the test preparation over those of the reference preparation were 0.9693-1.0739, 0.9598- 1.0561 and 0.9220 - 1.0642 respectively. Throughout the study period, no serious drug reaction was observed. However, a total of 26 adverse events (AE)/side effects were reported, including 24 that were definitely related to the study drugs, namely giddiness (n=17), while diarrheoa (n=3), headache (n=2) and excessive hunger (n=2) were less commonly reported by the subjects.
CONCLUSION: It can be concluded that the test preparation is bioequivalent to the reference preparation.
Fulltext Ondansetron against metoclopramide/dexamethasone--a comparative study

Lim AKH, Haron MR, Yap TM

Med J Malaysia, 1994 Sep;49(3):231-8.
PMID: 7845271

This trial was carried out in Hospital Kuala Lumpur. Fifty-two patients who were scheduled to receive their first or subsequent courses of cancer chemotherapy with single dose cisplatinum containing chemotherapy regimens were evaluated. Thirty-four patients were given ondansetron in one group while 18 in the other group received metoclopramide with dexamethasone. The response to treatment was categorised as complete (0 emetic episode), major (1 or 2 emetic episodes), minor (3 to 5 emetic episodes) or failure (> 5 emetic episodes or rescue medication). Among the 52 patients, a complete or major control (0 to 2 emetic episodes) was achieved in 23/34 patients (68%) from the ondansetron group and in 3/18 patients (17%) from the metoclopramide with dexamethasone group (p < 0.002) on day 1. Similarly, the control of nausea was greater in the ondansetron group compared with the metoclopramide with dexamethasone group (p < 0.0009) on day 1. Two patients were excluded (dropped out) after day one from each of the two study groups due to excessive vomiting subsequent to cisplatinum therapy. From days 2 to 6, there was a trend in favour of ondansetron. Both treatments were well tolerated. The results of this trial show that in the prophylaxis of nausea and vomiting induced by cisplatinum containing chemotherapy, the efficacy of ondansetron is superior to that of a standard anti-emetic combination, metoclopramide with dexamethasone.
Fulltext Barriers to and Facilitators of Cervical Cancer Screening among Women in Southeast Asia: A Systematic Review

Chua B, Ma V, Asjes C, Lim A, Mohseni M, Wee HL

Int J Environ Res Public Health, 2021 Apr 26;18(9).
PMID: 33926019 DOI: 10.3390/ijerph18094586

In Southeast Asia, cervical cancer is the second most common cancer in women. Low coverage for cervical cancer screening (CCS) becomes a roadblock to disease detection and treatment. Existing reviews on CCS have limited insights into the barriers and facilitators for SEA. Hence, this study aims to identify key barriers and facilitators among women living in SEA. A systematic literature review was conducted on Pubmed, Embase, PsycINFO, CINAHL, and SCOPUS. Primary qualitative and quantitative studies published in English that reported barriers and facilitators to CCS were included. The Mix Methods Appraisal Tool was used for the quality assessment of the included studies. Among the 93 included studies, pap smears (73.1%) were the most common screening modality. A majority of the studies were from Malaysia (35.5%). No studies were from Timor-Leste and the Philippines. The most common barriers were embarrassment (number of articles, n = 33), time constraints (n = 27), and poor knowledge of screening (n = 27). The most common facilitators were related to age (n = 21), receiving advice from healthcare workers (n = 17), and education status (n = 11). Findings from this review may inform health policy makers in developing effective cervical cancer screening programs in SEA countries.
Novel life-history data for threatened seahorses provide insight into fishery effects

Lawson JM, Foster SJ, Lim AC, Chong VC, Vincent AC

J Fish Biol, 2015 Jan;86(1):1-15.
PMID: 25307290 DOI: 10.1111/jfb.12527

Life-history variables for three incidentally captured species of seahorse (Kellogg's seahorse Hippocampus kelloggi, the hedgehog seahorse Hippocampus spinosissimus and the three-spot seahorse Hippocampus trimaculatus) were established using specimens obtained from 33 fisheries landing sites in Peninsular Malaysia. When samples were pooled by species across the peninsula, sex ratios were not significantly different from unity, and height and mass relationships were significant for all species. For two of these species, height at physical maturity (HM ) was smaller than the height at which reproductive activity (HR ) commenced: H. spinosissimus (HM = 99·6 mm, HR = 123·2 mm) and H. trimaculatus (HM = 90·5 mm, HR = 121·8 mm). For H. kelloggi, HM could not be estimated as all individuals were physically mature, while HR = 167·4 mm. It appears that all three Hippocampus spp. were, on average, caught before reproducing; height at 50% capture (HC ) was ≥HM but ≤HR . The results from this study probe the effectiveness of assessment techniques for data-poor fisheries that rely heavily on estimates of length at maturity, especially if maturity is poorly defined. Findings also question the sustainability of H. trimaculatus catches in the south-west region of Peninsular Malaysia, where landed specimens had a notably smaller mean height (86·2 mm) and markedly skewed sex ratio (6% males) compared with samples from the south-east and north-west of the peninsula.
Fulltext Are Indians and females less tolerant to pain? An observational study using a laboratory pain model

Das Gupta E, Zailinawati AH, Lim AW, Chan JB, Yap SH, Hla YY, et al.

Med J Malaysia, 2009 Jun;64(2):111-3.
PMID: 20058568 MyJurnal

In Malaysia, it is a common belief among health care workers that females and Indians have lower pain threshold. This experience, although based on anecdotal experience in the healthcare setting, does not allow differentiation between pain tolerance, and pain expression. To determine whether there is a difference in the tolerance to pain between the three main ethnic groups, namely the Malays, Chinese and Indians as well as between males and females. This was a prospective study, using a laboratory pain model (ischaemic pain tolerance) to determine the pain tolerance of 152 IMU medical students. The mean age of the students was 21.8 years (range 18-29 years). All of them were unmarried. The median of ischaemic pain tolerance for Malays, Chinese and Indians were 639s, 695s and 613s respectively (p = 0.779). However, statistically significant difference in ischaemic pain tolerance for males and females Indian students were observed. Possible ethnic difference in pain tolerance in casual observation is not verified by this laboratory pain model. Difference in pain tolerance between genders is shown only for Indians.
Fulltext Synthesis, Characterization, Adsorption Isotherm, and Kinetic Study of Oil Palm Trunk-Derived Activated Carbon for Tannin Removal from Aqueous Solution

Lim A, Chew JJ, Ngu LH, Ismadji S, Khaerudini DS, Sunarso J

ACS Omega, 2020 Nov 10;5(44):28673-28683.
PMID: 33195920 DOI: 10.1021/acsomega.0c03811

Oil palm trunk (OPT) represents one of the five main oil palm biomass wastes with high carbon content that can be economically converted to a large surface area, porous activated carbon (AC) adsorbent to treat palm oil mill effluent wastewater in Indonesia and Malaysia. In the first portion of this work, the design of the experiment was used to determine the optimum set of synthesis parameters required to maximize the iodine number of AC [i.e., Brunauer-Emmett-Teller (BET) specific surface area indicator] prepared from OPT via chemical activation route using H3PO4. The iodine numbers of AC and AC yield were probed as the impregnation ratio, the activation time, and the activation temperature were varied in the range of 0.28-3.47, 5.68-69.32 min, and 379-521 °C, respectively. An impregnation ratio of 2.29, an activation time of 6 min, and an activation temperature of 450 °C were identified as the optimum set of synthesis parameters. In the second portion of the work, the AC synthesized using the optimum parameters were then characterized and tested as an adsorbent for tannin. N2 sorption results revealed that the AC exhibits type IV isotherm, that is, contains micropores and mesopores and displays a relatively high BET specific surface area of 1657 m2 g-1. Adsorption equilibria isotherms for tannin adsorption onto the AC were collected at three different pH of 2, 4, and 6 and were nonlinearly fitted using Langmuir and Freundlich isotherm models, where the Langmuir isotherm gave better fitting than Freundlich. The higher adsorption capacity at lower pH can be explained in terms of the absence of electrostatic repulsion interaction between the AC surface and the tannic acid species as suggested by the point of zero charges (pHpzc) of 4.8 and an increasing ionization of tannic acid with pH rise between 4 and 7. Adsorption kinetics data were also obtained at four different pH of 2, 4, 6, and 8 where the nonlinear pseudo-first-order model best fitted the kinetic at pH of 2 and the nonlinear pseudo-second-order model represented the kinetic best at the remaining higher pH, which suggests that tannin adsorption onto AC occurred by physisorption at pH of 2 and by chemisorption at pH of 4, 6, and 8.
ENTEROAGGREGATIVE ESCHERICHIA COLI O104 FROM THAI AND IMPORTED MALAYSIAN RAW BEEF

Wameadesa N, Sae-lim A, Hayeebilan F, Rattanachuay P, Sukhumungoon P

Southeast Asian J. Trop. Med. Public Health, 2017 Mar;48(2):338-50.
PMID: 29642296

Local Thai and imported Malaysian beef in southern Thailand area carry
several Shiga toxin-producing Escherichia coli (STEC) serotypes. STEC O104 is an
important pathogen capable of causing outbreaks with considerable morbidity
and mortality. This study investigated the presence of E. coli O104 from local Thai
and imported Malaysian beef obtained from markets in Hat Yai City, Songkhla
Province during August 2015 - February 2016. Thirty-one E. coli O104 strains
were isolated from 12 beef samples (16% and 23% Thai and imported Malaysian,
respectively). Thirty strains possessed aggA (coding for a major component of
AAF/I fimbriae), a gene associated with enteroaggregative E. coli (EAEC) pathotype,
and all strains carried fimH (encoding Type 1 fimbriae). Thirty strains
belonged to phylogenetic group B1 and one strain (from Malaysian beef) to group
A. Agglutination of yeast cells was observed among 29 E. coli O104 strains. Investigation
of stx2 phage occupancy loci demonstrated that sbcB was occupied in 12
strains. Antimicrobial susceptibility assay revealed that 7 strains were resistant
to at least one antimicrobial agent and two were multi-drug resistant. One strain
carried extended spectrum β-lactamase gene blaCTX-M and three carried blaTEM. PFGE-generated DNA profiling showed identical DNA pattern between that of
one EAEC O104 strain from Thai beef and another from Malaysian beef, indicating
that these two strains originated from the same clone. This is the first report
in Thailand describing the presence of EAEC O104 from both Thai and imported
Malaysian beef and their transfer between both countries. Thorough surveillance
of this pathogen in fresh meats and vegetables should help to prevent any possible
outbreak of E. coli O104.
Metastatic alveolar rhabdomyosarcoma on the fine-needle aspiration cytology of cervical lymph node in an elderly patient, with FISH confirmation: A case report

Zhao Z, Takano A, Lim AST, Lim TH, Selvarajan S

Malays J Pathol, 2020 Apr;42(1):115-119.
PMID: 32342940

INTRODUCTION: Alveolar rhabdomyosarcoma (RMS) usually occurs in adolescents and young adults, and most frequently arises in the extremities.
CASE REPORT: We present a rare case of metastatic alveolar RMS from a nasal primary to cervical lymph nodes (LNs) in an elderly patient, diagnosed on the fine-needle aspiration (FNA) biopsy. Smears showed malignant round cells featuring focal rhabdoid appearance, with rhabdomyoblastic differentiation further supported by immunocytochemical stains. Diagnosis of alveolar RMS was confirmed by fluorescence in situ hybridization (FISH) identifying FOXO1 gene involvement with dual colour break-apart probes at locus 13q14.
DISCUSSION: The differential diagnosis for a small round blue cell tumour in the elderly generally includes metastatic small cell carcinoma, lymphoma, malignant melanoma, RMS, desmoplastic small round cell tumour and Ewing's sarcoma/primitive neuroectodermal tumour. Subtle morphological analysis and expression pattern of immunostaining for skeletal muscle differentiation led to the diagnosis of RMS. Cytogenetic testing on the FOXO1 gene rearrangement helps definite subtyping of alveolar RMS.
Stimulus-response incompatibility eliminates inhibitory cueing effects with saccadic but not manual responses

Eng V, Lim A, Kwon S, Gan SR, Jamaluddin SA, Janssen SMJ, et al.

Atten Percept Psychophys, 2017 May;79(4):1097-1106.
PMID: 28229429 DOI: 10.3758/s13414-017-1295-8

There are thought to be two forms of inhibition of return (IOR) depending on whether the oculomotor system is activated or suppressed. When saccades are allowed, output-based IOR is generated, whereas input-based IOR arises when saccades are prohibited. In a series of 4 experiments, we mixed or blocked compatible and incompatible trials with saccadic or manual responses to investigate whether cueing effects would follow the same pattern as those observed with more traditional peripheral onsets and central arrows. In all experiments, an uninformative cue was displayed, followed by a cue-back stimulus that was either red or green, indicating whether a compatible or incompatible response was required. The results showed that IOR was indeed observed for compatible responses in all tasks, whereas IOR was eliminated for incompatible trials-but only with saccadic responses. These findings indicate that the dissociation between input- and output-based forms of IOR depends on more than just oculomotor activation, providing further support for the existence of an inhibitory cueing effect that is distinct to the manual response modality.
Exploring the temporal dynamics of inhibition of return using steady-state visual evoked potentials

Lim A, Janssen SMJ, Satel J

Cogn Affect Behav Neurosci, 2020 12;20(6):1349-1364.
PMID: 33236297 DOI: 10.3758/s13415-020-00846-w

Inhibition of return is characterized by delayed responses to previously attended locations when the interval between stimuli is long enough. The present study employed steady-state visual evoked potentials (SSVEPs) as a measure of attentional modulation to explore the nature and time course of input- and output-based inhibitory cueing mechanisms that each slow response times at previously stimulated locations under different experimental conditions. The neural effects of behavioral inhibition were examined by comparing post-cue SSVEPs between cued and uncued locations measured across two tasks that differed only in the response modality (saccadic or manual response to targets). Grand averages of SSVEP amplitudes for each condition showed a reduction in amplitude at cued locations in the window of 100-500 ms post-cue, revealing an early, short-term decrease in the responses of neurons that can be attributed to sensory adaptation, regardless of response modality. Because primary visual cortex has been found to be one of the major sources of SSVEP signals, the results suggest that the SSVEP modulations observed were caused by input-based inhibition that occurred in V1, or visual areas earlier than V1, as a consequence of reduced visual input activity at previously cued locations. No SSVEP modulations were observed in either response condition late in the cue-target interval, suggesting that neither late input- nor output-based IOR modulates SSVEPs. These findings provide further electrophysiological support for the theory of multiple mechanisms contributing to behavioral cueing effects.
Looking at remembering: Eye movements, pupil size, and autobiographical memory

Janssen SMJ, Foo A, Johnson SN, Lim A, Satel J

Conscious Cogn, 2021 03;89:103089.
PMID: 33607423 DOI: 10.1016/j.concog.2021.103089

To examine the relationship between visual imagery and autobiographical memory, eye position and pupil size were recorded while participants first searched for memories and then reconstructed the retrieved memories (Experiment 1), or only searched for memories (Experiment 2). In Experiment 1, we observed that, although recollective experience was not associated with the number of fixations per minute, memories that took longer to retrieve were linked to increased pupil size. In Experiment 2, we observed that directly retrieved memories were recalled more quickly and were accompanied by smaller pupils than generatively retrieved memories. After correcting for response time, retrieval mode also produced an effect, showing that decreased pupil size is not simply due to directly retrieved memories being recalled more quickly. These findings provide compelling evidence that objective measures, such as pupil size, can be used alongside subjective measures, such as self-reports, to distinguish between directly retrieved and generatively retrieved memories.
Time course of inhibition of return in a spatial cueing paradigm with distractors

Eng V, Lim A, Janssen SMJ, Satel J

Acta Psychol (Amst), 2018 Feb;183:51-57.
PMID: 29328938 DOI: 10.1016/j.actpsy.2017.12.011

Studies of endogenous and exogenous attentional orienting in spatial cueing paradigms have been used to investigate inhibition of return, a behavioral phenomenon characterized by delayed reaction time in response to recently attended locations. When eye movements are suppressed, attention is covertly oriented to central or peripheral stimuli. Overt orienting, on the other hand, requires explicit eye movements to the stimuli. The present study examined the time course of slowed reaction times to previously attended locations when distractors are introduced into overt and covert orienting tasks. In a series of experiments, manual responses were required to targets following central and peripheral cues at three different cue-target intervals, with and without activated oculomotor systems. The results demonstrate that, when eye movements are suppressed, behavioral inhibition is reduced or delayed in magnitude by the presence of a distractor relative to conditions without distractors. However, the time course of behavioral inhibition when eye movements are required remains similar with or without distractors.
Sensory adaptation and inhibition of return: dissociating multiple inhibitory cueing effects

Lim A, Eng V, Janssen SMJ, Satel J

Exp Brain Res, 2018 05;236(5):1369-1382.
PMID: 29520444 DOI: 10.1007/s00221-018-5225-3

Inhibition of return (IOR) refers to an increase in reaction times to targets that appeared at a previously cued location relative to an uncued location, often investigated using a spatial cueing paradigm. Despite numerous studies that have examined many aspects of IOR, the neurophysiological mechanisms underlying IOR are still in dispute. The objective of the current research is to investigate the plausible mechanisms by manipulating the cue and target types between central and peripheral stimuli in a traditional cue-target paradigm with saccadic responses to targets. In peripheral-cueing conditions, we observed inhibitory cueing effects across all cue-target onset asynchronies (CTOAs) with peripheral targets, but IOR was smaller and arose later with central targets. No inhibition was observed in central-cueing conditions at any CTOAs. Empirical data were simulated using a two-dimensional dynamic neural field model. Our results and simulations support previous work demonstrating that, at short CTOAs, behavioral inhibition is only observed with repeated stimulation-an effect of sensory adaptation. With longer CTOAs, IOR is observed regardless of target type when peripheral cueing is used. Our findings suggest that behaviorally exhibited inhibitory cueing effects can be attributed to multiple mechanisms, including both attenuation of visual stimulation and local inhibition in the superior colliculus.
Fulltext Epidemiology and clinical characteristics of HIV-infected patients in Kuala Lumpur

Cheong I, Lim A, Lee C, Ibrahim Z, Sarvanathan K

Med J Malaysia, 1997 Dec;52(4):313-7.
PMID: 10968106

Between 1987 to 1995, a total of 334 patients infected with HIV were treated at the Hospital Kuala Lumpur. There were 159 Malays, 108 Chinese, 64 Indians, and 3 from other ethnic groups. Three hundred and twenty-one (96.1%) of these individuals were males and 262 (65.9%) were between the ages of 26-45 years. Intravenous drug users made up 77% (256) of the attributable risk behaviour from the group although many of them also had added risk behaviours like heterosexual activity with multiple partners (50 patients), tattoos (7 patients), homosexual practice (4 patients) and previous transfusions (3 patients). The others acquired their infection through heterosexual promiscuity (59 patients), homo/bisexual activity (7 patients), previous transfusion (5 patients) and tattoos (1 patient). Sixty-six patients (all males) had since progressed to full blown AIDS and 10 have died. The two commonest AIDS-defining events were tuberculosis infection and Pneumocystic carinii pneumonia occurring in 37 (56%) and 15 (22.7%) of patients respectively. Forty-one patients with AIDS presented for the first time with their AIDS-defining infections. The mean CD4 count of the patients when they progressed to AIDS was 130/mm3. The mean time for progression from "known" seropositivity to AIDS was 2.42 years. These results suggest that Malaysians infected with HIV are not coming forward for treatment until they are in the advanced stage of the disease.
Fulltext A rare case of nasopharyngeal carcinosarcoma

Lim AL, Zahirrudin Z, Pua KC

Med J Malaysia, 2012 Aug;67(4):428-9.
PMID: 23082458 MyJurnal

Nasopharnygeal carcinoma is known to be the commonest tumour of the nasopharynx. However, the incidence of nasopharngeal carcinosarcoma is extremely rare. Carcinosarcoma has been reported to be aggressive in nature and therefore early diagnosis and prompt treatment is important. We report a young lady who was diagnosed with nasopharyngeal carcinosarcoma in our centre. She presented with only 2 weeks history of nose block and was noted to have a mass occupying the nasopharynx with neck metastasis. She underwent panendoscope and biopsy with radical radiotherapy.
Fulltext Immunological profiles of immune restoration disease presenting as mycobacterial lymphadenitis and cryptococcal meningitis

Tan DB, Yong YK, Tan HY, Kamarulzaman A, Tan LH, Lim A, et al.

HIV Med, 2008 May;9(5):307-16.
PMID: 18400078 DOI: 10.1111/j.1468-1293.2008.00565.x

A proportion of HIV patients beginning antiretroviral therapy (ART) develop immune restoration disease (IRD). Immunological characteristics of IRD were investigated in a cohort of HIV patients beginning therapy in Kuala Lumpur, Malaysia.
Orthography-phonology consistency in English: Theory- and data-driven measures and their impact on auditory vs. visual word recognition

Lim A, O'Brien B, Onnis L

Behav Res Methods, 2024 Mar;56(3):1283-1313.
PMID: 37553536 DOI: 10.3758/s13428-023-02094-5

Research on orthographic consistency in English words has selectively identified different sub-syllabic units in isolation (grapheme, onset, vowel, coda, rime), yet there is no comprehensive assessment of how these measures affect word identification when taken together. To study which aspects of consistency are more psychologically relevant, we investigated their independent and composite effects on human reading behavior using large-scale databases. Study 1 found effects on adults' naming responses of both feedforward consistency (orthography to phonology) and feedback consistency (phonology to orthography). Study 2 found feedback but no feedforward consistency effects on visual and auditory lexical decision tasks, with the best predictor being a composite measure of consistency across grapheme, rime, OVC, and word-initial letter-phoneme. In Study 3, we explicitly modeled the reading process with forward and backward flow in a bidirectionally connected neural network. The model captured latent dimensions of quasi-regular mapping that explain additional variance in human reading and spelling behavior, compared to the established measures. Together, the results suggest interactive activation between phonological and orthographic word representations. They also validate the role of computational analyses of language to better understand how print maps to sound, and what properties of natural language affect reading complexity.
Sound production in the tiger-tail seahorse Hippocampus comes: Insights into the sound producing mechanisms

Lim AC, Chong VC, Chew WX, Muniandy SV, Wong CS, Ong ZC

J Acoust Soc Am, 2015 Jul;138(1):404-12.
PMID: 26233039 DOI: 10.1121/1.4923153

Acoustic signals of the tiger-tail seahorse (Hippocampus comes) during feeding were studied using wavelet transform analysis. The seahorse "click" appears to be a compounded sound, comprising three acoustic components that likely come from two sound producing mechanisms. The click sound begins with a low-frequency precursor signal, followed by a sudden high-frequency spike that decays quickly, and a final, low-frequency sinusoidal component. The first two components can, respectively, be traced to the sliding movement and forceful knock between the supraorbital bone and coronet bone of the cranium, while the third one (purr) although appearing to be initiated here is produced elsewhere. The seahorse also produces a growling sound when under duress. Growling is accompanied by the highest recorded vibration at the cheek indicating another sound producing mechanism here. The purr has the same low frequency as the growl; both are likely produced by the same structural mechanism. However, growl and purr are triggered and produced under different conditions, suggesting that such "vocalization" may have significance in communication between seahorses.
A study of pollen prevalence in relation to pollen allergy in Malaysian asthmatics

Sam CK, Kesavan-Padmaja, Liam CK, Soon SC, Lim AL, Ong EK

Asian Pac J Allergy Immunol, 1998 Mar;16(1):1-4.
PMID: 9681122

In this paper we report results of skin prick tests (SPT) using pollen extracts on 200 patients with clinical symptoms of asthma, and results of a parallel study in which pollen was collected and classified over a period of 18 months. The patients were outpatients from the University Hospital in Kuala Lumpur, Malaysia, while the pollen grains were collected with a spore trap placed in the campus of the University of Malaya, approximately one kilometer from the University Hospital. Pollen extracts of 3 grasses (Bahia, Bermuda, rough pigweed) and 2 flowering trees, Acacia and Melaleuca, were used in the SPT. Of the 29.5% asthmatics with positive SPT reactions, 21.5% were to one or more of the grass pollens, 21.5% to Acacia and 7.5% to Melaleuca pollen. Acacia and Bermuda grass extracts were the most allergenic, which agreed with results of the pollen collection which showed grass and Acacia pollen grains to be the two most commonly found pollens.

Study site: University Malaya Medical Centre (UMMC)

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