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Fulltext Begoniayenyeniae (Begoniaceae), a new species from Endau Rompin National Park, Johor, Malaysia

Tan JP, Tam SM, Kiew R

PhytoKeys, 2018.
PMID: 30416344 DOI: 10.3897/phytokeys.110.25846

Begoniayenyeniae is a new species of horticultural value known only from the Endau Rompin National Park, Peninsular Malaysia. It is similar to Begoniarajah with which it had previously been confused in the number of tepals and leaf characters. The new species is compared with three similar species, B.foxworthyi, B.rajah and B.reginula and photographs of all four species and descriptions of B.yenyeniae and B.rajah are provided. Molecular analysis using the ndhF-rpl132 chloroplast marker confirms the four species as distinct. Amongst native species, the three variegated species, B.yenyeniae, B.rajah and B.reginula, are some of the most popular Malaysian begonias in cultivation. Based on its restricted distribution, Begoniayenyeniae, under the IUCN Red List Categories and Criteria, is assessed as Critically Endangered.
Preeminent productivity of 1,3-propanediol by Clostridium butyricum JKT37 and the role of using calcium carbonate as pH neutraliser in glycerol fermentation

Tee ZK, Jahim JM, Tan JP, Kim BH

Bioresour Technol, 2017 Jun;233:296-304.
PMID: 28285221 DOI: 10.1016/j.biortech.2017.02.110

Calcium carbonate was evaluated as a replacement for the base during the fermentation of glycerol by a highly productive strain of 1,3-propanediol (PDO), viz., Clostridium butyricum JKT37. Due to its high specific growth rate (µmax=0.53h(-1)), 40g/L of glycerol was completely converted into 19.6g/L of PDO in merely 7h of batch fermentation, leaving only acetate and butyrate as the by-products. The accumulation of these volatile fatty acids was circumvented with the addition of calcium carbonate as the pH neutraliser before the fermentation was inoculated. An optimal amount of 15g/L of calcium carbonate was statistically determined from screening with various glycerol concentrations (20-120g/L). By substituting potassium hydroxide with calcium carbonate as the pH neutraliser for fermentation in a bioreactor, a similar yield (YPDO/glycerol=0.6mol/mol) with a constant pH was achieved at the end of the fermentation.
Negative automatic thoughts as a mediator of the relationship between depression and suicidal behaviour in an at-risk sample of Malaysian adolescents

Choon MW, Abu Talib M, Yaacob SN, Awang H, Tan JP, Hassan S, et al.

Child Adolesc Ment Health, 2015 May;20(2):89-93.
PMID: 32680393 DOI: 10.1111/camh.12075

BACKGROUND: This study examined the mediating role of negative automatic thoughts in the relationship between depression and suicidal behaviour in a sample of at-risk Malaysian adolescents.
METHOD: A total of 1441 adolescents were initially recruited via multistage cluster sampling. Subsequently, 294 at-risk adolescents were selected for further analyses through a specified cut-off score.
RESULTS: The results showed significant positive relationships among the study variables. Specifically, negative automatic thoughts emerged as a significant mediator in the relation between depression and suicidal behaviour (z = 7.15, p
Homogeneous solid dispersion (HSD) system for rapid and stable production of succinic acid from lignocellulosic hydrolysate

Luthfi AAI, Tan JP, Harun S, Manaf SFA, Jahim JM

Bioprocess Biosyst Eng, 2019 Jan;42(1):117-130.
PMID: 30259181 DOI: 10.1007/s00449-018-2019-8

Continuous bio-production of succinic acid was reported in homogeneous solid dispersion (HSD) system utilizing porous coconut shell activated carbon (CSAC) as immobilization carrier. The aim of the present work was to implement the HSD system to increase the area of cell immobilization and the rate of succinic-acid production from the lignocellulosic medium. The ratio of the two enzymes (cellulase-to-hemicellulase) was initially optimized to break down the lignocellulose into its free monomers, wherein the best ratio was determined as 4:1. Succinic-acid production was evaluated in the HSD system by varying the substrate loading and dilution rate. The results showed that high productivities of succinic acid were obtained when 60 g/L glucose was fed over a dilution rates ranging from 0.03 to 0.4/h. The titer of succinic acid decreased gradually with higher dilution rate, whereas the residual substrate concentration increased with it. Critical dilution rate was determined to be 0.4/h at which the best productivity of succinic acid of 6.58 g/L h and its yield of 0.66 g/g were achieved using oil palm fronds (OPF) hydrolysate. This work lends evidence to the use of CSAC and lignocellulosic hydrolysate to further exploit the potential economies of scale.
Fulltext Asian "Guan" Parenting and Life Satisfaction Among Adolescents in Malaysia: The Mediating Role of Filial Piety

Nainee S, Tan SA, Tan CS, Gan SW, Tan JP

Front Psychol, 2021;12:746540.
PMID: 34899486 DOI: 10.3389/fpsyg.2021.746540

Literature on adolescent development has shown that parenting practices have positive relationships with adolescents' life satisfaction. Adolescents' life satisfaction improves when they have parents low in psychological control who uphold reciprocal self-disclosure in their communication. Guan parenting was found to correlate positively with adolescents' development. Therefore, it is methodologically important to replicate the investigation on the relationship between adolescents' life satisfaction and Guan parenting. Literature suggests that filial piety is shaped by parenting practices and adolescents who perceived intense parental concern, care, and involvement tend to uphold filial piety and express gratitude toward parents which may promote the adolescents' life satisfaction. In this study, mediation analysis was done to elucidate the relationship among parents' guan parenting style, filial piety, and life satisfaction on 606 adolescents (Mage=15.07; SDage=1.03; 52.1% females) in Malaysia. The adolescents were sampled through cluster sampling, and data were collected using self-administered questionnaires. The results showed positive relationship between paternal and maternal guan parenting with filial piety and adolescents' life satisfaction. Greater parents' filial piety was linked to higher life satisfaction among adolescents. Findings from the mediation models indicated the association among guan parenting with filial piety, gratitude toward parents, and higher life satisfaction. The findings also offered empirical evidence to the underlying mechanism of how guan parenting could affect adolescent life satisfaction via the mediating role of filial piety. The findings also supported the importance of culture-infused parenting in inculcating adolescents' filial piety besides establishing its link to life satisfaction in Asian families.
Evaluating the filial behaviour scale across three cultural groups using exploratory structural equation modelling

Zong X, Ingoglia S, Lo Coco A, Tan JP, Inguglia C, Liga F, et al.

Int J Psychol, 2023 Feb;58(1):42-51.
PMID: 36181306 DOI: 10.1002/ijop.12880

Filial piety is a Confucian concept that guides how children treat and take care of their parents. The Filial Behaviour Scale (FBS) is a 25-item instrument developed in the Chinese context measuring behavioural manifestations of filial piety. Although the components of filial piety have been found to be relevant across cultures, little research has investigated the psychometric properties of the FBS in other cultural contexts. The present study evaluated the factor structure, internal consistency, measurement invariance and construct validity of the FBS across three cultural groups: the United States, Italy and Malaysia. Participants were 1090 emerging adults (67% females; Mage = 21.29 years, SD = 1.97; White Americans: n = 455, White Italians: n = 428, Malays: n = 328). A two-factor structure emerged across groups: Obedience/Obligation (behaviours showing obedience and obligation towards parents) and Relationship (behaviours expressing affection and promoting positive parent-child relationships). The two factors demonstrated adequate internal consistency, full configural, partial metric and partial scalar invariance, as well as unique associations with depressive symptoms and parent-child relationships across groups. These findings yielded a more nuanced understanding of filial behaviour and supported the utility of a two-factor FBS among emerging adults in various cultural contexts.
The contributions of grandparents to preadolescent grandchildren's social skills in rural Malaysia

Tan JP, Gan SW, Cheah CSL, Tan SA, Nainee S, Yap CC, et al.

J Res Adolesc, 2024 Jun;34(2):410-435.
PMID: 38797867 DOI: 10.1111/jora.12959

This study aimed to generate localized knowledge by investigating the perceptions and experiences of preadolescent grandchildren and grandparents regarding grandparenting and intergenerational interactions and how these processes were related to the social skills of preadolescents from three ethnic groups in Malaysia. Using a concurrent quantitative-qualitative mixed method research design, Chinese, Malay, and Indian preadolescents (N = 465; ages 9-12 years old; M = 10.27 years; SD = 1.03) from rural areas in Malaysia completed a self-administered quantitative survey; furthermore, 25 grandparents participated in one-on-one interviews. Survey findings showed that preadolescent grandchildren who reported higher grandparental warmth and support had greater social skills, mediated by positive grandparent-grandchildren (GP-GC) relationships. The GP-GC relationship and preadolescent social skills association was stronger for skipped generation compared to three-generation households. Interview findings revealed that grandparents expressed unconditional love and autonomy support in their grandparenting roles by guiding and encouraging their preadolescent grandchildren to make decisions. The GP-GC interactions served as a dynamic force in promoting preadolescents' social skills. By employing a decolonized approach and drawing on the lived experiences of grandparents from three ethnic backgrounds in rural Malaysia, the study provided an understanding of grandparenting practices and their general implications across the three ethnic groups. The interview responses highlighted both commonalities and specificities in grandparenting practices and relationship dynamics shaped by religious, class, and sociocultural dimensions in rural Malaysia.
Nickel-iron doped on granular activated carbon for efficient immobilization in biohydrogen production

Jamaludin NFM, Abdullah LC, Idrus S, Engliman NS, Tan JP, Jamali NS

Bioresour Technol, 2024 Jan;391(Pt A):129933.
PMID: 37898370 DOI: 10.1016/j.biortech.2023.129933

Nickel-iron doped granular activated carbon (GAC-N) was used to enhance immobilization in biohydrogen production. The effect of the sludge ratio to GAC-N, ranged 1:0.5-4, was studied. The optimum hydrogen yield (HY) of 1.64 ± 0.04 mol H2/mol sugar consumed and hydrogen production rate (HPR) of 45.67 ± 1.00 ml H2/L.h was achieved at a ratio of 1:1. Immobilization study was performed at 2 d HRT with a stable HY of 2.94 ± 0.16 mol H2/mol sugar consumed (HPR of 83.10 ± 4.61 ml H2/L.h), shorten biohydrogen production from 66 d to 26 d, incrementing HY by 57.30 %. The Monod model resulted in the optimum initial sugar, maximum specific growth rate, specific growth rate, and cell growth saturation coefficient at 20 g/L, 2.05 h-1, 1.98 h-1 and 6.96 g/L, respectively. The dominant bacteria identified was Thermoanaerobacterium spp. The GAC-N showed potential as a medium for immobilization to improve biohydrogen production.
Biotechnological enhancement of lactic acid conversion from pretreated palm kernel cake hydrolysate by Actinobacillus succinogenes 130Z

Rahim NA, Luthfi AAI, Bukhari NA, Tan JP, Abdul PM, Manaf SFA

Sci Rep, 2023 Apr 08;13(1):5787.
PMID: 37031272 DOI: 10.1038/s41598-023-32964-z

The aim of this study was to establish an improved pretreatment and fermentation method i.e. immobilized cells for high recovery of fermentable sugars from palm kernel cake (PKC) and its effects on fermentability performance by Actinobacillus succinogenes 130Z in the conversion of the fermentable sugar to lactic acid. The effects of oxalic acid concentrations (1-6% w/v) and residence times (1-5 h) on the sugar recovery were initially investigated and it was found that the highest mannose concentration was 25.1 g/L at the optimum hydrolysis conditions of 4 h and 3% (w/v) oxalic acid. The subsequent enzymatic saccharification of the pretreated PKC afforded the highest enzymatic digestibility with the recovered sugars amounting to 25.18 g/L and 9.14 g/L of mannose and glucose, respectively. Subsequently, the fermentability performance of PKC hydrolysate was evaluated and compared in terms of cultivation phases (i.e. mono and dual-phases), carbonate loadings (i.e. magnesium and sodium carbonates), and types of sugars (i.e. glucose and mannose). The highest titer of 19.4 g/L lactic acid was obtained from the fermentation involving A. succinogenes 130Z in dual-phase cultivation supplemented with 30 g/L of magnesium carbonate. Lactic acid production was further enhanced by using immobilized cells with coconut shell-activated carbon (CSAC) of different sizes (A, B, C, and D) in the repeated batch cultivation of dual-phase fermentation producing 31.64 g/L of lactic acid. This work sheds light on the possibilities to enhance the utilization of PKC for lactic acid production via immobilized A. succinogenes 130Z.
Advancements in microbial-mediated radioactive waste bioremediation: A review

Tan JP, Clyde CW, Ng CC, Yeap SK, Yong CY

J Environ Radioact, 2024 Dec;280:107530.
PMID: 39378736 DOI: 10.1016/j.jenvrad.2024.107530

The global production of radioactive wastes is expected to increase in the coming years as more countries have resorted to adopting nuclear power to decrease their reliance on fossil-fuel-generated energy. Discoveries of remediation methods that can remove radionuclides from radioactive wastes, including those discharged to the environment, are therefore vital to reduce risks-upon-exposure radionuclides posed to humans and wildlife. Among various remediation approaches available, microbe-mediated radionuclide remediation have limited reviews regarding their advances. This review provides an overview of the sources and existing classification of radioactive wastes, followed by a brief introduction to existing radionuclide remediation (physical, chemical, and electrochemical) approaches. Microbe-mediated radionuclide remediation (bacterial, myco-, and phycoremediation) is then extensively discussed. Bacterial remediation involves biological processes like bioreduction, biosorption, and bioprecipitation. Bioreduction involves the reduction of water-soluble, mobile radionuclides to water-insoluble, immobile lower oxidation states by ferric iron-reducing, sulfate-reducing, and certain extremophilic bacteria, and in situ remediation has become possible by adding electron donors to contaminated waters to enrich indigenous iron- and sulfate-reducing bacteria populations. In biosorption, radionuclides are associated with functional groups on the microbial cell surface, followed by getting reduced to immobilized forms or precipitated intracellularly or extracellularly. Myco- and phycoremediation often involve processes like biosorption and bioaccumulation, where the former is influenced by pH and cell concentration. A Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis on microbial remediation is also performed. It is suggested that two research directions: genetic engineering of radiation-resistant microorganisms and co-application of microbe-mediated remediation with other remediation methods could potentially result in the discovery of in situ or ex situ microbe-involving radioactive waste remediation applications with high practicability. Finally, a comparison between the strengths and weaknesses of each approach is provided.
Multiple crystallization as a potential strategy for efficient recovery of succinic acid following fermentation with immobilized cells

Luthfi AAI, Tan JP, Isa NFAM, Bukhari NA, Shah SSM, Mahmod SS, et al.

Bioprocess Biosyst Eng, 2020 Jul;43(7):1153-1169.
PMID: 32095989 DOI: 10.1007/s00449-020-02311-x

This study aimed to enhance the crystallizability of bio-based succinic acid for its efficient recovery while maintaining the end product at the highest purity. Immobilization of Actinobacillus succinogenes was initially evaluated based on three different carriers: volcanic glass, clay pebbles, and silica particles. The adsorption capacity of metabolites with a low concentration (10 g/L) and a high concentration (40 g/L) was investigated. It was demonstrated that clay pebbles adsorbed the least succinic acid (
Parenting measurement, normativeness, and associations with child outcomes: Comparing evidence from four non-Western cultures

Ren H, Hart CH, Cheah CSL, Porter CL, Nelson DA, Yavuz-Müren HM, et al.

Dev Sci, 2024 Sep;27(5):e13388.
PMID: 36929667 DOI: 10.1111/desc.13388

This study compared parenting across four non-Western cultures to test cross-cultural commonality and specificity principles in three aspects: measurement properties, parenting normativeness, and their associations with child outcomes. Both mothers and fathers (N = 1509 dyads) with preschool-aged children (M = 5.00 years; 48% girls) from urban areas of four countries (Malaysia, N = 372; China, N = 441; Turkey, N = 402; and Japan, N = 294) reported on four parenting constructs (authoritative, authoritarian, group harmony socialization, and intrusive control) and their sub-dimensions using modified culturally relevant measures. Teachers reported on children's internalizing, externalizing, and prosocial behaviors. The commonality principle was supported by two sets of findings: (1) full measurement invariance was established for most parenting constructs and sub-dimensions, except that intrusive control only reached partial scalar invariance, and (2) no variations were found in associations between parenting and any child outcomes across cultures or parent gender at the construct level for all four parenting constructs and at the sub-dimensional level for authoritarian and intrusive control sub-dimensions. The specificity principle was supported by the other two sets of findings: (1) cross-cultural differences in parenting normativeness did not follow the pattern of economic development but yielded culture-specific patterns, and (2) at the sub-dimensional level, the authoritative parenting and group harmony socialization sub-dimensions were differently associated with child outcomes across cultures and/or parent gender. The findings suggested that examining specific dimensions rather than broad parenting constructs is necessary to reflect cultural specificities and nuances. Our study provided a culturally-invariant instrument and a three-step guide for future parenting research to examine cross-cultural commonalities/specificities. RESEARCH HIGHLIGHTS: This is the first study to use an instrument with measurement invariance across multiple non-Western cultures to examine the commonality and specificity principles in parenting. Measurement invariance was achieved across cultures for authoritative and authoritarian parenting, group harmony socialization, intrusive control, and their sub-dimensions, supporting the commonality principle. Cross-cultural differences in parenting normativeness did not follow the pattern of economic development but yielded culture-specific patterns, supporting the specificity principle. Both commonalities and specificities were manifested in associations between parenting and child outcomes across cultures.

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