Pub Date : 2024-07-31DOI: 10.17576/jsm-2024-5307-03
Mohamad Azam Akmal Abu-Bakar, N. R. Aifat, J. Rovie-Ryan, M. A. Abdul-Latiff, A. Ampeng, S. Md-Nor, B. M. Md-Zain
Two sympatric mousedeer species, Tragulus kanchil and Tragulus napu, inhabit the Malaysian tropical rainforests. Previous studies have established their phylogenetic relationships based on morphological variations; however, comprehensive genetic data have yet to be extensively used to relate the relationships especially from different populations. The main objectives of this study were to determine the phylogenetic relationships, population genetics, and phylogeography of mousedeer species based on DNA sequences of the mitochondrial D-loop region. DNA from 32 mousedeer samples, representing various populations in Malaysia, was sequenced and analyzed using Neighbor-Joining, Maximum Parsimony, and Bayesian Inference approaches. The phylogenetic analyses showed two main clades representing the populations of T. kanchil and T. napu. The results also showed that the T. kanchil populations in Borneo was separated from Peninsular Malaysia taxa in MP and BI phylogenetic tree. However, Borneo population was nested in east population of Peninsular Malaysia in NJ tree. In addition, the T. kanchil population in Peninsular Malaysia further separated into east and west coast populations of Titiwangsa Range. It was supported with finding in population genetic relation that showed relatively low levels among population. This is expected because some of the populations are isolated geographically. The divergence of these populations is likely due to the Titiwangsa Range which acts as a barrier separating the east and west Peninsular Malaysia populations, and the South China Sea separates the populations of Peninsular Malaysia and Borneo. Molecular clock tree reconstruction showed that the separation of T. kanchil and T. napu occurred around 17.11 million years ago (MYAs). Furthermore, the T. kanchil populations from the east and west Peninsular Malaysia showed a branching pattern from those of Borneo of about 11.04 and 9.14 MYAs, respectively. The results of this study increase our understanding of Malaysian mousedeer phylogeny and phylogeography.
马来西亚热带雨林中栖息着两种同域的啮齿目动物，Tragulus kanchil 和 Tragulus napu。以前的研究已经根据形态变化确定了它们的系统发育关系；然而，全面的遗传数据尚未被广泛用于联系它们之间的关系，特别是来自不同种群的数据。本研究的主要目的是根据线粒体 D 环区的 DNA 序列确定胭脂鱼物种的系统发育关系、种群遗传学和系统地理学。研究人员对代表马来西亚不同种群的32个水獭样本进行了DNA测序，并采用邻接法、最大解析法和贝叶斯推断法进行了分析。系统进化分析表明，有两个主要支系分别代表 T. kanchil 和 T. napu 的种群。结果还显示，在 MP 和 BI 系统发生树中，婆罗洲的 T. kanchil 种群与马来西亚半岛的分类群分开。然而，在 NJ 树中，婆罗洲种群与马来西亚半岛东部种群嵌套。此外，马来西亚半岛的T. kanchil种群进一步分离为Titiwangsa山脉的东西海岸种群。这与种群遗传关系的发现相吻合，种群间的遗传关系水平相对较低。这在意料之中，因为有些种群在地理上是孤立的。这些种群的分化很可能是由于Titiwangsa山脉作为屏障将马来西亚半岛的东部和西部种群分隔开来，而南中国海又将马来西亚半岛和婆罗洲的种群分隔开来。分子时钟树重建显示，T. kanchil 和 T. napu 的分离发生在大约 1711 万年前。此外，马来西亚半岛东部和西部的 T. kanchil 种群与婆罗洲的 T. napu 种群的分支模式分别为 11.04 百万年前和 9.14 百万年前。这项研究的结果增加了我们对马来西亚胭脂鱼系统发育和系统地理学的了解。
{"title":"Molecular Phylogenetics and Phylogeography of Malaysian Mousedeer (Tragulus kanchil) Based on Mitochondrial DNA Sequences of the D-Loop Region","authors":"Mohamad Azam Akmal Abu-Bakar, N. R. Aifat, J. Rovie-Ryan, M. A. Abdul-Latiff, A. Ampeng, S. Md-Nor, B. M. Md-Zain","doi":"10.17576/jsm-2024-5307-03","DOIUrl":"https://doi.org/10.17576/jsm-2024-5307-03","url":null,"abstract":"Two sympatric mousedeer species, Tragulus kanchil and Tragulus napu, inhabit the Malaysian tropical rainforests. Previous studies have established their phylogenetic relationships based on morphological variations; however, comprehensive genetic data have yet to be extensively used to relate the relationships especially from different populations. The main objectives of this study were to determine the phylogenetic relationships, population genetics, and phylogeography of mousedeer species based on DNA sequences of the mitochondrial D-loop region. DNA from 32 mousedeer samples, representing various populations in Malaysia, was sequenced and analyzed using Neighbor-Joining, Maximum Parsimony, and Bayesian Inference approaches. The phylogenetic analyses showed two main clades representing the populations of T. kanchil and T. napu. The results also showed that the T. kanchil populations in Borneo was separated from Peninsular Malaysia taxa in MP and BI phylogenetic tree. However, Borneo population was nested in east population of Peninsular Malaysia in NJ tree. In addition, the T. kanchil population in Peninsular Malaysia further separated into east and west coast populations of Titiwangsa Range. It was supported with finding in population genetic relation that showed relatively low levels among population. This is expected because some of the populations are isolated geographically. The divergence of these populations is likely due to the Titiwangsa Range which acts as a barrier separating the east and west Peninsular Malaysia populations, and the South China Sea separates the populations of Peninsular Malaysia and Borneo. Molecular clock tree reconstruction showed that the separation of T. kanchil and T. napu occurred around 17.11 million years ago (MYAs). Furthermore, the T. kanchil populations from the east and west Peninsular Malaysia showed a branching pattern from those of Borneo of about 11.04 and 9.14 MYAs, respectively. The results of this study increase our understanding of Malaysian mousedeer phylogeny and phylogeography.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141795709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.17576/jsm-2024-5307-11
Fatma Tajini, Awatef Jelassi, Amal Hamdani, Ali Salem, Ola Abdelhedi, Abid Ouerghui, H. Sebai
The present study aims to investigate the antioxidant and anti-constipation activities of the derived phenolic extracts in ribs wild cardoon (Cynara sylvestris). Analysed extracts (acetone, methanol and aqueous) exhibited high level of phenolic compounds and excellent antioxidant activities with significant IC50 values (p ≤0.05), as assessed by the DPPH radical-scavenging activity (0.84±0.08 - 2.44±0.007 μg/mL), ABTS cationic radical test (0.96 ±0.01- 136.67±6.75 μg/mL) and β-carotene bleaching assay (2.09±0.02-51.12±1.32 μg/mL). Also, higher levels of insoluble dietary fibers were found (56.18 ± 0.91% DW of neutral detergent fiber). The in vivo investigation was performed on Wistar rats to explore the ability of C. sylvestris aqueous extract (CSAE) in the enhancement of the gastrointestinal transit and the treatment of induced constipation by Loperamide (commercialized as Idium). A significant increase of 15, 24.5 and 32.4% in gastrointestinal motility was recordedwhen doses of CSAE increased (75, 150 and 300 mg/kg b.w, respectively). Food intake, water consumption, number and weight of stools were also increased in a dose-dependent manner, compared to the positive control (untreated). Moreover, CSAE provided significantly (p ≤0.05) and dose-dependently protection against oxidative stress by preserving normal antioxidant enzymes activities (SOD and GPx) in intestinal and colonic mucosa, and resorted hepatic enzymes (AST and ALT) and renal (urea and creatinine) levels to normal values. These results can be explained by the abundance of phenolic compounds and insoluble fibers in this plant. Therefore, its use can be encouraged in alimentary and pharmaceutical applications as antioxidant and laxative food supplements.
{"title":"Antioxidant Activities and Laxative Effect of Bioactive Compounds from Cynara cardunculus var. sylvestris","authors":"Fatma Tajini, Awatef Jelassi, Amal Hamdani, Ali Salem, Ola Abdelhedi, Abid Ouerghui, H. Sebai","doi":"10.17576/jsm-2024-5307-11","DOIUrl":"https://doi.org/10.17576/jsm-2024-5307-11","url":null,"abstract":"The present study aims to investigate the antioxidant and anti-constipation activities of the derived phenolic extracts in ribs wild cardoon (Cynara sylvestris). Analysed extracts (acetone, methanol and aqueous) exhibited high level of phenolic compounds and excellent antioxidant activities with significant IC50 values (p ≤0.05), as assessed by the DPPH radical-scavenging activity (0.84±0.08 - 2.44±0.007 μg/mL), ABTS cationic radical test (0.96 ±0.01- 136.67±6.75 μg/mL) and β-carotene bleaching assay (2.09±0.02-51.12±1.32 μg/mL). Also, higher levels of insoluble dietary fibers were found (56.18 ± 0.91% DW of neutral detergent fiber). The in vivo investigation was performed on Wistar rats to explore the ability of C. sylvestris aqueous extract (CSAE) in the enhancement of the gastrointestinal transit and the treatment of induced constipation by Loperamide (commercialized as Idium). A significant increase of 15, 24.5 and 32.4% in gastrointestinal motility was recordedwhen doses of CSAE increased (75, 150 and 300 mg/kg b.w, respectively). Food intake, water consumption, number and weight of stools were also increased in a dose-dependent manner, compared to the positive control (untreated). Moreover, CSAE provided significantly (p ≤0.05) and dose-dependently protection against oxidative stress by preserving normal antioxidant enzymes activities (SOD and GPx) in intestinal and colonic mucosa, and resorted hepatic enzymes (AST and ALT) and renal (urea and creatinine) levels to normal values. These results can be explained by the abundance of phenolic compounds and insoluble fibers in this plant. Therefore, its use can be encouraged in alimentary and pharmaceutical applications as antioxidant and laxative food supplements.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141795469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.17576/jsm-2024-5307-07
S. Yong, C. P. Teoh, Paris Leonardo Lavin, Marcelo A. González, Clemente Michael Vui Ling Wong
Antarctic microbes have evolved and adapted unique strategies to survive in the harsh polar environment. Apart from the ability to adapt to the low nutrient soil content and extremely dry and cold polar environment, a particular strategy used by Antarctic bacteria is the production of antimicrobial compounds that can eliminate rivals in the same niche, giving them a competitive edge over other microbes. In contrast, it is unclear whether spore-forming microbes possess similar antimicrobial properties as one of their survival strategies, especially those from the Antarctic volcanic Deception island in the West Antarctic. Hence, this study aims to isolate and characterize the spore-forming microbes in Deception Island, Antarctica, as well as to identify the ones that are equipped with the ability to inhibit other microorganisms. Microbes were isolated using various growth media and were segregated into clusters based on their random amplified polymorphic DNA (RAPD) fingerprints. A total of 90 strains were isolated and clustered into 30 groups at a similarity of 60%. Representative strains from each cluster were assayed for antimicrobial activities against 13 Gram-positive and Gram-negative test bacteria comprising human pathogens. Twenty-five strains exhibited the ability to inhibit at least one test bacterium. The four strains, A60, Im31, Im32 and Im33 that showed the strongest inhibitory activities were subjected to 16S or 18S rDNA sequencing and analysis to identify them. They were identified as Pseudogymnoascus, Bacillus, Leohumicola, and Talaromyces spp. The ability of the aforementioned microbes to thrive in harsh environments and compete with fierce competitors for scarce nutrients is probably due to their ability to produce antimicrobial compounds that target and kill their rivals.
{"title":"Antarctic Spore-Forming Microorganisms from Deception Island Inhibit the Growth of Various Bacterial Strains","authors":"S. Yong, C. P. Teoh, Paris Leonardo Lavin, Marcelo A. González, Clemente Michael Vui Ling Wong","doi":"10.17576/jsm-2024-5307-07","DOIUrl":"https://doi.org/10.17576/jsm-2024-5307-07","url":null,"abstract":"Antarctic microbes have evolved and adapted unique strategies to survive in the harsh polar environment. Apart from the ability to adapt to the low nutrient soil content and extremely dry and cold polar environment, a particular strategy used by Antarctic bacteria is the production of antimicrobial compounds that can eliminate rivals in the same niche, giving them a competitive edge over other microbes. In contrast, it is unclear whether spore-forming microbes possess similar antimicrobial properties as one of their survival strategies, especially those from the Antarctic volcanic Deception island in the West Antarctic. Hence, this study aims to isolate and characterize the spore-forming microbes in Deception Island, Antarctica, as well as to identify the ones that are equipped with the ability to inhibit other microorganisms. Microbes were isolated using various growth media and were segregated into clusters based on their random amplified polymorphic DNA (RAPD) fingerprints. A total of 90 strains were isolated and clustered into 30 groups at a similarity of 60%. Representative strains from each cluster were assayed for antimicrobial activities against 13 Gram-positive and Gram-negative test bacteria comprising human pathogens. Twenty-five strains exhibited the ability to inhibit at least one test bacterium. The four strains, A60, Im31, Im32 and Im33 that showed the strongest inhibitory activities were subjected to 16S or 18S rDNA sequencing and analysis to identify them. They were identified as Pseudogymnoascus, Bacillus, Leohumicola, and Talaromyces spp. The ability of the aforementioned microbes to thrive in harsh environments and compete with fierce competitors for scarce nutrients is probably due to their ability to produce antimicrobial compounds that target and kill their rivals.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141795147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.17576/jsm-2024-5307-01
Amna Marium, Huma Naz, Tanveer Ahmed, Muhammad Umar Ijaz, Muhammad Usman, Zahid Manzoor, Basharat Ali, Awatif Omran, Yasmene F. Alanazi, Rasha M.A. Jame, Ayman El Sabagh
This research was designed to assess the toxicity of cadmium (Cd), and its effects on catalase (CAT) activity, histology of gills and geno-toxicity of Oreochromis niloticus. The acute toxicity of Cd (96-h) for fish was computed as 56.021 mg/L (LC50) and 80.7336 mg/L (LC100) using Probit method. The inferences showed that catalase level was significantly (P<0.05) lower in Cd treated O. niloticus as compared to control that was metal-stress free. It followed the order as: intestine
{"title":"Evaluation of Catalase Activity, Gill Histology and Genotoxic Effects of Cadmium in Tilapia (Oreochromis Niloticus) Fingerlings","authors":"Amna Marium, Huma Naz, Tanveer Ahmed, Muhammad Umar Ijaz, Muhammad Usman, Zahid Manzoor, Basharat Ali, Awatif Omran, Yasmene F. Alanazi, Rasha M.A. Jame, Ayman El Sabagh","doi":"10.17576/jsm-2024-5307-01","DOIUrl":"https://doi.org/10.17576/jsm-2024-5307-01","url":null,"abstract":"This research was designed to assess the toxicity of cadmium (Cd), and its effects on catalase (CAT) activity, histology of gills and geno-toxicity of Oreochromis niloticus. The acute toxicity of Cd (96-h) for fish was computed as 56.021 mg/L (LC50) and 80.7336 mg/L (LC100) using Probit method. The inferences showed that catalase level was significantly (P<0.05) lower in Cd treated O. niloticus as compared to control that was metal-stress free. It followed the order as: intestine<gills<muscles<brain. Results of gills histology showed that Cd-exposure caused prominent damage to both primary and secondary lamella. The histological alterations included fusion and curling of secondary lamella, hyperplasia in secondary lamella, epithelial lifting, and aneurysm observed in gills. Geno-toxic results showed that a significant (p<0.05) increase in micronuclei, de-shape and notched nuclei in erythrocytes of Cd-exposed O. niloticus was found as compared to control. The inferences of this study confirmed the genotoxic properties of Cd. This study will be helpful in understanding the histological and geno-toxic changes in fish body kept under Cd stress. This study will also help in the development of a specific approach to minimize the negative and genotoxic impacts of cadmium. Furthermore, tilapia can be used as a good bio-indicator for detecting toxic impacts associated with water pollution.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141795491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.17576/jsm-2024-5307-10
Amer Izzat Samsudin, Sharmilah Vetaryan, W. Y. Hooi, Yang Ping Lee
Banana (Musa spp.) is an economically important crop widely consumed all over the world. Understanding the genetic diversity and relatedness between various banana cultivars is important to continuously improve its fruit characteristics, nutritional value, and disease resistance. This study aimed to develop a DNA fingerprinting panel using polymorphic simple sequence repeat (SSR) markers for the genetic characterisation of 11 banana cultivars in Malaysia. A total of 10 polymorphic SSR markers were developed into a multiplex PCR reaction and capillary electrophoresis to uniquely profile our collection of banana cultivars. The developed fingerprinting panel successfully amplified a total of 95 alleles, with 6 to 13 alleles per SSR marker. The average SSR marker polymorphic information content (PIC) value is 0.812, indicating the informativeness of the panel. Analysis of molecular variance (AMOVA) shows that 97% of the molecular variance from our banana collection is due to inter-variety genetic diversity, while the remaining 3% is due to intra-variety genetic diversity. A population structure analysis groups our collection of banana varieties according to the presence of at least one M. balbisiana (B) genome in their genetic makeup. The Cavendish variety, however, showed a distinct structure compared to the other cultivars. This SSR fingerprinting panel provides valuable insights into the genetic diversity and relatedness between banana cultivars in Malaysia. It has the potential to assist future banana breeding initiatives and serve as an effective quality control measure for verifying varieties in a tissue culture facility involved in banana planting materials production.
香蕉（Musa spp.）了解各种香蕉栽培品种之间的遗传多样性和亲缘关系对于不断改进其果实特性、营养价值和抗病性非常重要。本研究旨在利用多态性简单序列重复（SSR）标记开发一个 DNA 指纹图谱面板，以确定马来西亚 11 个香蕉栽培品种的遗传特征。通过多重 PCR 反应和毛细管电泳，共开发出 10 个多态性 SSR 标记，对我们收集的香蕉栽培品种进行了独特的分析。所开发的指纹识别面板共成功扩增出 95 个等位基因，每个 SSR 标记有 6 至 13 个等位基因。SSR 标记的平均多态信息含量（PIC）值为 0.812，表明该面板的信息量很大。分子方差分析（AMOVA）显示，我们的香蕉样本中 97% 的分子方差来自品种间的遗传多样性，其余 3% 来自品种内的遗传多样性。种群结构分析根据香蕉品种的遗传结构中至少存在一个 M. balbisiana (B) 基因组对香蕉品种进行了分组。然而，与其他品种相比，卡文迪许（Cavendish）品种显示出独特的结构。这个 SSR 指纹图谱小组为了解马来西亚香蕉栽培品种的遗传多样性和亲缘关系提供了宝贵的信息。它有潜力协助未来的香蕉育种计划，并可作为一种有效的质量控制措施，在香蕉种植材料生产的组织培养设施中验证品种。
{"title":"Assessment of Genetic Diversity and Relatedness of Local Banana (Musa spp.) Cultivars in Malaysia Using Simple Sequence Repeat (SSR) Markers","authors":"Amer Izzat Samsudin, Sharmilah Vetaryan, W. Y. Hooi, Yang Ping Lee","doi":"10.17576/jsm-2024-5307-10","DOIUrl":"https://doi.org/10.17576/jsm-2024-5307-10","url":null,"abstract":"Banana (Musa spp.) is an economically important crop widely consumed all over the world. Understanding the genetic diversity and relatedness between various banana cultivars is important to continuously improve its fruit characteristics, nutritional value, and disease resistance. This study aimed to develop a DNA fingerprinting panel using polymorphic simple sequence repeat (SSR) markers for the genetic characterisation of 11 banana cultivars in Malaysia. A total of 10 polymorphic SSR markers were developed into a multiplex PCR reaction and capillary electrophoresis to uniquely profile our collection of banana cultivars. The developed fingerprinting panel successfully amplified a total of 95 alleles, with 6 to 13 alleles per SSR marker. The average SSR marker polymorphic information content (PIC) value is 0.812, indicating the informativeness of the panel. Analysis of molecular variance (AMOVA) shows that 97% of the molecular variance from our banana collection is due to inter-variety genetic diversity, while the remaining 3% is due to intra-variety genetic diversity. A population structure analysis groups our collection of banana varieties according to the presence of at least one M. balbisiana (B) genome in their genetic makeup. The Cavendish variety, however, showed a distinct structure compared to the other cultivars. This SSR fingerprinting panel provides valuable insights into the genetic diversity and relatedness between banana cultivars in Malaysia. It has the potential to assist future banana breeding initiatives and serve as an effective quality control measure for verifying varieties in a tissue culture facility involved in banana planting materials production.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141795431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.17576/jsm-2024-5307-16
Amber Asghar, A. Sanaullah, Muhammad Hanif, Laila A. Al-Essa
To enhance precision in estimating unknown population parameters, an auxiliary variable is often used. However, in scenarios where required information on an auxiliary variable is partially or fully unavailable, two-phase sampling is commonly employed. The challenge of estimating the variance vector using multi-auxiliary variables is a less explored area in current literature. This paper addresses the estimation of vector of unknown population variances for multiple study variables by using an estimated vector of variances derived from multi-auxiliary information. This approach is particularly relevant when population variances for the multi-auxiliary variables are not known prior to the survey. The paper introduces a generalized variance and a vector of biases for the proposed multivariate estimator. Special cases of the proposed multivariate variance estimator are provided, accompanied by expressions for mean square errors. Theoretical mathematical conditions are discussed to guide the preference for the proposed estimator. Through the analysis of real-world application-based data, the applicability and efficiency of the proposed multivariate variance estimator are demonstrated, outperforming modified versions of multivariate variance estimators. Additionally, a simulation study validates the superior performance of the proposed estimator compared to its modified estimators.
{"title":"Enhancing Precision in Population Variance Vector Estimation: A Two-Phase Sampling Approach with Multi-Auxiliary Information","authors":"Amber Asghar, A. Sanaullah, Muhammad Hanif, Laila A. Al-Essa","doi":"10.17576/jsm-2024-5307-16","DOIUrl":"https://doi.org/10.17576/jsm-2024-5307-16","url":null,"abstract":"To enhance precision in estimating unknown population parameters, an auxiliary variable is often used. However, in scenarios where required information on an auxiliary variable is partially or fully unavailable, two-phase sampling is commonly employed. The challenge of estimating the variance vector using multi-auxiliary variables is a less explored area in current literature. This paper addresses the estimation of vector of unknown population variances for multiple study variables by using an estimated vector of variances derived from multi-auxiliary information. This approach is particularly relevant when population variances for the multi-auxiliary variables are not known prior to the survey. The paper introduces a generalized variance and a vector of biases for the proposed multivariate estimator. Special cases of the proposed multivariate variance estimator are provided, accompanied by expressions for mean square errors. Theoretical mathematical conditions are discussed to guide the preference for the proposed estimator. Through the analysis of real-world application-based data, the applicability and efficiency of the proposed multivariate variance estimator are demonstrated, outperforming modified versions of multivariate variance estimators. Additionally, a simulation study validates the superior performance of the proposed estimator compared to its modified estimators.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141795514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.17576/jsm-2024-5307-17
Syahrul Idzuan Mohamad, Nur Riza Mohd Suradi, Faridatulazna Ahmad Shahabuddin
These days, public service performance is determined by competitiveness. Due to a prolonged period of stagnation, Malaysia's competitive performance is at a critical level. The public service is therefore under pressure to demonstrate that all policies and programs are highly valued. This study aims to determine the primary variables influencing the ability of Malaysia's public services to compete. Data were acquired through surveys completed by 373 respondents from 26 ministries. The relationships between talent management, human capital, and competitiveness were analysed using structural equation modelling. The results indicate a significant and positive relationship between talent management and competitiveness, with human capital serving as a significant partial mediator. This study highlights the direct importance of talent management for public services competitiveness and its indirect impact through human capital. These insights can assist policymakers in developing a strategic framework to keep the Malaysian public service competitive.
{"title":"Mediating Effects in The Structural Equation Model of Malaysian Public Service Competitiveness","authors":"Syahrul Idzuan Mohamad, Nur Riza Mohd Suradi, Faridatulazna Ahmad Shahabuddin","doi":"10.17576/jsm-2024-5307-17","DOIUrl":"https://doi.org/10.17576/jsm-2024-5307-17","url":null,"abstract":"These days, public service performance is determined by competitiveness. Due to a prolonged period of stagnation, Malaysia's competitive performance is at a critical level. The public service is therefore under pressure to demonstrate that all policies and programs are highly valued. This study aims to determine the primary variables influencing the ability of Malaysia's public services to compete. Data were acquired through surveys completed by 373 respondents from 26 ministries. The relationships between talent management, human capital, and competitiveness were analysed using structural equation modelling. The results indicate a significant and positive relationship between talent management and competitiveness, with human capital serving as a significant partial mediator. This study highlights the direct importance of talent management for public services competitiveness and its indirect impact through human capital. These insights can assist policymakers in developing a strategic framework to keep the Malaysian public service competitive.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141795409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.17576/jsm-2024-5307-18
Arnita Arnita, F. Marpaung, Fanny Ramadhani, Dewan Dinata
Discussing poverty is crucial because it affects many facets of society, including socioeconomic disparity, crime, and the inability to obtain high-quality education. One of the provinces with the highest poverty rate in Indonesia is North Sumatra. A strategy is required to gather accurate data to effectively reduce poverty. Poverty mapping and prediction were conducted in North Sumatra to get a precise spatial distribution of poverty, the operation of the poverty model, and forecasting using machine learning (ML). Poverty prediction was conducted using a random forest (RF) algorithm and poverty mapping was conducted using the K-Means algorithm. The poverty mapping showed a significant inertia value decline in the third and fourth clusters of the elbow graph. The third cluster (0.313) was superior to the fourth cluster (0.244) in the silhouette index. Thus, there were three poverty clusters - low, medium, and high - that were used in the model. The best model was created using the grid search cross-validation, while the best prediction results were created using the RF algorithm, with the following parameters: n-estimator = 50, max depth = 10, min samples split = 2, and min samples leaf = 1. The mean squared error (MSE) of the RF model's predictions was 0.002617, or satisfactory precision.
{"title":"Machine Learning for Mapping and Forecasting Poverty in North Sumatera: A Data-Driven Approach","authors":"Arnita Arnita, F. Marpaung, Fanny Ramadhani, Dewan Dinata","doi":"10.17576/jsm-2024-5307-18","DOIUrl":"https://doi.org/10.17576/jsm-2024-5307-18","url":null,"abstract":"Discussing poverty is crucial because it affects many facets of society, including socioeconomic disparity, crime, and the inability to obtain high-quality education. One of the provinces with the highest poverty rate in Indonesia is North Sumatra. A strategy is required to gather accurate data to effectively reduce poverty. Poverty mapping and prediction were conducted in North Sumatra to get a precise spatial distribution of poverty, the operation of the poverty model, and forecasting using machine learning (ML). Poverty prediction was conducted using a random forest (RF) algorithm and poverty mapping was conducted using the K-Means algorithm. The poverty mapping showed a significant inertia value decline in the third and fourth clusters of the elbow graph. The third cluster (0.313) was superior to the fourth cluster (0.244) in the silhouette index. Thus, there were three poverty clusters - low, medium, and high - that were used in the model. The best model was created using the grid search cross-validation, while the best prediction results were created using the RF algorithm, with the following parameters: n-estimator = 50, max depth = 10, min samples split = 2, and min samples leaf = 1. The mean squared error (MSE) of the RF model's predictions was 0.002617, or satisfactory precision.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141795091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.17576/jsm-2024-5307-14
Li-Yen Lee Michelle, Ishak Ahmad, S. Phang
Hexanoic acid-doped polyaniline (PAni) is a great potential candidate to replace conventional adsorbent towards the removal of heavy metal waste from electroplating industry, especially nickel (Ni). In this study, different weight % (wt %) of titanium dioxide (TiO2) and carboxymethyl cellulose (CMC) are added to form PAni composites with enhanced Ni removal efficiency. All the synthesized samples were examined with FTIR, UV-Vis, conductivity measurement, XRD, TGA, and FESEM to confirm their chemical structures, oxidation states, electrical conductivity, crystallinity and incorporation of metal oxide, thermal stability, and surface morphology, respectively. Among the different samples, PAni / TiO2 20 % exhibited the highest Ni removal efficiency of 37.5 %. Upon further addition of CMC, PAni / TiO2 / CMC 5 % showed the highest Ni removal efficiency of 89.08 %. Optimization of the experimental parameters were conducted and a maximum Ni removal efficiency of 97.88 % was achieved at pH 10, 30 min contact time at a temperature of 30 °C, and with an adsorbent dosage of 0.01 g. This study shows that the composite of PAni / TiO2 / CMC 5 % shows good potential to be applied as adsorbent of the removal of Ni ions.
{"title":"Preparation and Optimization of Polyaniline/ Titanium Dioxide/ Carboxymethyl Cellulose Powder for Effective Nickel Adsorption","authors":"Li-Yen Lee Michelle, Ishak Ahmad, S. Phang","doi":"10.17576/jsm-2024-5307-14","DOIUrl":"https://doi.org/10.17576/jsm-2024-5307-14","url":null,"abstract":"Hexanoic acid-doped polyaniline (PAni) is a great potential candidate to replace conventional adsorbent towards the removal of heavy metal waste from electroplating industry, especially nickel (Ni). In this study, different weight % (wt %) of titanium dioxide (TiO2) and carboxymethyl cellulose (CMC) are added to form PAni composites with enhanced Ni removal efficiency. All the synthesized samples were examined with FTIR, UV-Vis, conductivity measurement, XRD, TGA, and FESEM to confirm their chemical structures, oxidation states, electrical conductivity, crystallinity and incorporation of metal oxide, thermal stability, and surface morphology, respectively. Among the different samples, PAni / TiO2 20 % exhibited the highest Ni removal efficiency of 37.5 %. Upon further addition of CMC, PAni / TiO2 / CMC 5 % showed the highest Ni removal efficiency of 89.08 %. Optimization of the experimental parameters were conducted and a maximum Ni removal efficiency of 97.88 % was achieved at pH 10, 30 min contact time at a temperature of 30 °C, and with an adsorbent dosage of 0.01 g. This study shows that the composite of PAni / TiO2 / CMC 5 % shows good potential to be applied as adsorbent of the removal of Ni ions.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141795301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.17576/jsm-2024-5307-09
N. Zakaria, Z. Berahim, M. A. Md Hatta, M. Omar, R. Rosle, Mohd Razi Ismail, Nik Norasma Che’Ya, Asyraf Azmi, Mohammad Iqbal Hakim Mohd Azhan
The production of drought-tolerant rice varieties in Malaysia and the information regarding the response of local varieties to water stress are still lacking. Therefore, this experiment was conducted to determine the growth, physiological performance, molecular response, and yield of ten available rice varieties, namely MR 219, MR 220-CL2, MR 297, MRQ 76, Vietnam Hybrid, UKM RC2, UKM RC8, Putra 1, MR 303, and MR 307, under ten days of cyclic water stress. The experiment was arranged in a Randomized Complete Block Design (RCBD) with three replications. Plant height, tiller number, photosynthesis rate, stomatal conductance, transpiration rate, chlorophyll content, biomass partitioning, genotyping of SSR markers, days of harvest, and yield component were measured. Results showed that water limitations reduced tiller number per hill, while plant height, leaf dry matter, and panicle length were enhanced. It was found that MR 297 had the shortest plant height, while MR 220-CL2 had a short maturity period, a shorter panicle length, and an enhanced filled grain percentage. Putra 1 and UKM RC8 showed a higher photosynthesis rate, stomatal conductance, and transpiration rate under water limitation at 99 days after sowing (DAS). Under well-watered conditions, the total grain weight per pot of Putra 1 and MR 307 was enhanced compared to MR 219. Meanwhile, under water limitation, the total grain weight per pot of UKM RC2, MR 220-CL2, MR 307, MR 297, and Vietnam Hybrid was comparable to MR 219 and slightly enhanced in UKM RC8, Putra 1, and MR 303. Among the tested varieties, MR 220-CL2 can be selected based on early maturity criteria for the potential development of drought-tolerant varieties.
{"title":"Physiological and Yield Performance of Commercial Rice Varieties under Cyclic Water Stress in Malaysia","authors":"N. Zakaria, Z. Berahim, M. A. Md Hatta, M. Omar, R. Rosle, Mohd Razi Ismail, Nik Norasma Che’Ya, Asyraf Azmi, Mohammad Iqbal Hakim Mohd Azhan","doi":"10.17576/jsm-2024-5307-09","DOIUrl":"https://doi.org/10.17576/jsm-2024-5307-09","url":null,"abstract":"The production of drought-tolerant rice varieties in Malaysia and the information regarding the response of local varieties to water stress are still lacking. Therefore, this experiment was conducted to determine the growth, physiological performance, molecular response, and yield of ten available rice varieties, namely MR 219, MR 220-CL2, MR 297, MRQ 76, Vietnam Hybrid, UKM RC2, UKM RC8, Putra 1, MR 303, and MR 307, under ten days of cyclic water stress. The experiment was arranged in a Randomized Complete Block Design (RCBD) with three replications. Plant height, tiller number, photosynthesis rate, stomatal conductance, transpiration rate, chlorophyll content, biomass partitioning, genotyping of SSR markers, days of harvest, and yield component were measured. Results showed that water limitations reduced tiller number per hill, while plant height, leaf dry matter, and panicle length were enhanced. It was found that MR 297 had the shortest plant height, while MR 220-CL2 had a short maturity period, a shorter panicle length, and an enhanced filled grain percentage. Putra 1 and UKM RC8 showed a higher photosynthesis rate, stomatal conductance, and transpiration rate under water limitation at 99 days after sowing (DAS). Under well-watered conditions, the total grain weight per pot of Putra 1 and MR 307 was enhanced compared to MR 219. Meanwhile, under water limitation, the total grain weight per pot of UKM RC2, MR 220-CL2, MR 307, MR 297, and Vietnam Hybrid was comparable to MR 219 and slightly enhanced in UKM RC8, Putra 1, and MR 303. Among the tested varieties, MR 220-CL2 can be selected based on early maturity criteria for the potential development of drought-tolerant varieties.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141795891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：