Physical and antimicrobial characterization of self assembled silver nanoparticle/chitosan onto low density polyethylene film as active packaging polymer

Colloidal Silver nanoparticles with a size of 5 nm produced by chemical reduction using poly ethylene glycol (PEG 200). Layers of silver nanoparticles and chitosan were deposited onto low density polyethylene (LDPE) substrate by layer by layer (LBL) self-assembly technique. Silver nanocomposite films were built by sequential dipping of LDPE film in either anionic silver nanoparticles or cationic chitosan. Silver nanoparticles and chitosan led to the formation of nanocomposite films possessing antimicrobial properties with the thickness of 2, 4, 8, 12 and 20 layers. Silver nanocomposite films were characterized by atomic force microscopy (AFM). Thermal, mechanical and barrier properties of LBL deposited nanocomposite films were investigated. Results showed that the LBL deposition of silver nanoparticles and chitosan increased the crystallinity of the composites and also improved mechanical and barrier properties of LDPE film significantly (p<0.05). Antimicrobial activity of silver nanocomposites against Escherichia coli and Staphylococcus aureus was evaluated. Growth kinetic parameters of E.coli and S.aureus affected by silver nanocomposites were calculated by modeling of absorbance data according to Gomperz equation. LDPE-silver nanocomposite affected bacterial growth parameters significantly (p<0.05). The specific growth rate reduced from 0.30 to 0.11 h-1 for E. coli and decreased 0.27 to 0.06 h-1 for S. aureus

Pembangunan Identitas Keagamaan dalam Ruang Digital (Studi Kasus tentang Kristen Cabang Muhammadiyah di Media Sosial)

This research aims to understand the development of the religious identity of Kristen Cabang Muhammadiyah on social media. The method used is a qualitative approach with Twitter social media analysis. The research findings indicate that social media plays a significant role in the construction of religious identity in the digital era. Through social media, individuals and religious groups can interact, share information, and strengthen their religious identity. Strategies for developing religious identity on social media include disseminating relevant content, building online communities, collaborating with religious figures, promoting engagement in offline activities, and strengthening solidarity among religious followers. Social media content analysis shows that the response to Kristen Cabang Muhammadiyah is still limited and does not indicate a sustained discussion trend. The impact of social media activities on religious identity includes increasing awareness, expanding message reach, building communities, and enhancing public understanding. This research provides valuable insights for understanding the dynamics of religious identity in the digital space and the relationship between religions in Indonesia and the influence of social media on them

Knowledge, attitude and practice on leptospirosis among undergraduate students in University Putra Malaysia

Introduction: Leptospirosis is an infectious and zoonotic disease caused by pathogenic bacteria called leptospires which can be transmitted through the exposure to the urine or excretion of infected animals, and also water or soil that being contaminated with secretion of the infected animals. Leptospirosis remains a concern in Malaysia, as the number of cases had steadily increased. This study aims to determine the knowledge, attitude and practice (KAP) among final year students of selected programmes in Universiti Putra Malaysia (UPM). Methods: A cross sectional study was conducted among students of Environmental and Occupational Health (ENVOCH) (57 students), Nursing (22 students) and Veterinary Medicine (97 students). Thus, the total sample sizes were 170, however the response rate were 81.76%. Questionnaire was used as the study instrumentation. Results: There was a significant association between race and knowledge, also gender and attitude with p<0.05, (p=0.008) and (p=0.001) respectively. Furthermore, there was also an association between attitude and practice (p<0.05). Meanwhile, there was a significant difference on the knowledge between students of ENVOCH with Veterinary Medicine and Nursing with Veterinary Medicine (p<0.05). Conclusion: Most of the final year students in this study had moderate level of KAP towards Leptospirosis disease. Thus, improvement in education and training must be done to face this issue

Diversity of Trichoderma species isolated from soil

Soils consist of complex mixtures of mineral, water, air, organic matter and as an ecosystem of a large number of countless microorganisms such as bacteria, fungi and nematodes. Due to the limitation on understanding of fungi biodiversity in soil, many people do not know there consists of very useful microbe that can help in suppression of plant pathogens. Trichoderma (Hypocreales, Ascomycota) is one of the microorganisms that living in all types of soil. Trichoderma species has been used as a biological control agent of phytopathogens due to its abundance and having an antagonistic property. This study will provide checklists of Trichoderma species that have been isolated from cultivated crop soils in Malaysia. The objectives of this study are to isolate and identify Trichoderma species from soil based on morphological characterization and to calculate diversity of Trichoderma species based on Shannon-Wiener Index. Soil samples from each cultivated agricultural crops were collected in three spots in 17 locations around Malaysia. Isolation of Trichoderma was completed using soil dilution technique to obtain a pure single colony-forming unit (CFU). A total of 253 of Trichoderma isolates were successfully isolated from rhizosphere of different crops. All isolates were tentatively identified into six species such as T. harzianum (114 isolates), T. asperellum (65 isolates), T. hamatum (22 isolates), T. viride (26 isolates),T. koningii (20 isolates) and T. virens (6 isolates).The differences between species were characterized based on their colony features, pigmentation on potato dextrose agar (PDA) and the branching of conidiophores. The diversity index of Trichoderma species found in the Malaysia soil was 1.43 and T. harzianum was dominated. Due to diverse species of Trichoderma found in Malaysia, it will increase the opportunity in selection for biological control agent of plant diseases

What are the Features of Quality for Arabic Teachers Agreed by Students and Teachers?

Teacher is an important factor swaying students’ achievement. The success of an educational entity reflects the quality of the teachers engaged. Teacher factor is identified as one of the main obstacles to the Arabic education. Assessment process of the teachers’ quality would help those concerned identify the weakness before preventive and remedial actions being taken. This study intends to identify the features of quality for Arabic teachers agreed by students and teachers as the first step in a continuous assessment of the teachers’ quality. The respondents of the qualitative approach are 9 excellent Arabic teachers and 90 students from SMKA throughout Malaysia. The qualitative data are analyzed through descriptive and comparative methods using the Atlas.ti. installer. The finding of this study regarding the experiences of excellent Arabic teachers shows that there are 17 GBA quality characteristics that are seen in 4 categories, i.e. 1) Personality, 2) Assessment and Feedback, 3) Class and Student Management, and 4) Teaching and Learning (T&amp;L). The outcome also uncovers types of similarity and difference in determining the teachers’ quality based on teacher and student perspective. The teachers are found as leaning to more comprehensive assessment compared to the students who prioritize the quality of a good teacher-student relationship

DNA Strand Patterns on Aluminium Thin Films

A new patterning method using Deoxyribose Nucleic Acid (DNA) strands capable of producing nanogaps of less than 100 nm is proposed and investigated in this work. DNA strands from Bosenbergia rotunda were used as the fundamental element in patterning DNA on thin films of aluminium (Al) metal without the need for any lithographic techniques. The DNA strands were applied in buffer solutions onto thin films of Al on silicon (Si) and the chemical interactions between the DNA strands and Al creates nanometer scale arbitrary patterning by direct transfer of the DNA strands onto the substrate. This simple and cost-effective method can be utilized in the fabrication of various components in electronic chips for microelectronics and Nano Electronic Mechanical System (NEMS) applications in general

Comorbidities Associated With Attention-Deficit/Hyperactivity Disorder in Children and Adolescents at a Tertiary Care Setting

Studies have revealed high rates of neurodevelopmental and psychiatric comorbid conditions among individuals diagnosed with attention-deficit/hyperactivity disorder (ADHD). However, research on this topic in the Arab world has been limited. This study evaluates the medical, neurodevelopmental, and psychiatric comorbidities in children and adolescents diagnosed with ADHD in Dubai, United Arab Emirates (UAE). A total of 428 pediatric patients diagnosed with ADHD were included. Children and adolescents with ADHD had high rates of comorbid disorders. Twenty comorbid conditions were identified. More than 3 quarters of the study sample had at least 1 comorbid disorder. The most common comorbidity among children was autism spectrum disorder, and among adolescents was anxiety disorders. Comprehensive assessments are highly warranted to identify and manage associated comorbid conditions. Further research is needed in exploring the biopsychosocial factors contributing to the elevated rate of comorbidity in children and adolescents with ADHD

Silver/poly (lactic acid) nanocomposites: preparation, characterization, and antibacterial activity

In this study, antibacterial characteristic of silver/poly (lactic acid) nanocomposite (Ag/PLA-NC) films was investigated, while silver nanoparticles (Ag-NPs) were synthesized into biodegradable PLA via chemical reduction method in diphase solvent. Silver nitrate and sodium borohydride were respectively used as a silver precursor and reducing agent in the PLA, which acted as a polymeric matrix and stabilizer. Meanwhile, the properties of Ag/PLA-NCs were studied as a function of the Ag-NP weight percentages (8, 16, and 32 wt% respectively), in relation to the use of PLA. The morphology of the Ag/PLA-NC films and the distribution of the Ag-NPs were also characterized. The silver ions released from the Ag/PLA-NC films and their antibacterial activities were scrutinized. The antibacterial activities of the Ag/PLA-NC films were examined against Gram-negative bacteria (Escherichia coli and Vibrio parahaemolyticus) and Gram-positive bacteria (Staphylococcus aureus) by diffusion method using Muller–Hinton agar. The results indicated that Ag/PLA-NC films possessed a strong antibacterial activity with the increase in the percentage of Ag-NPs in the PLA. Thus, Ag/PLA-NC films can be used as an antibacterial scaffold for tissue engineering and medical application

Characterization and biocompatibility properties of silver nanoparticles produced using short chain polyethylene glycol

Silver nanoparticles are of interest due to their unique physicochemical and antimicrobial properties. The nanoparticles were produced by chemical reduction using short chain polyethylene glycol (PEG) as reducing agent, solvent and stabilizer in absence of other chemicals. Silver nanoparticles were separated from colloidal dispersion by ultra centrifuge at 14000 rpm. The reduction of silver ion (Ag+) to silver nanoparticles (Agº) was monitored by pH measurement and UV-visible spectroscopy of colloidal dispersion at fixed intervals. Silver nanoparticles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM) and diphenyl-picrylhydrazyl (DPPH) radical scavenging method. Antimicrobial activity of silver nanoparticles was investigated against Escherichia coli, Staphylococcus aureus and Vibrio parahaemolyticus by agar plate test. Results indicated 51.5% conversion efficiency of silver ions to silver nanoparticles. Colloidal dispersion containing 4.12 mg/ml silver nanoparticles showed uniform size of 5.5 ± 1.1 nm with a typical visible spectra band at 447 nm. Silver nanoparticles showed significant (p < 0.05) antimicrobial efficiency and with concentration of 100 ppm resulted in 46.22%, 66.51% and 69.06% inhibition against S. aureus, E. coli and V. parahaemolyticus, respectively. The nanoparticles were also found to reduce DPPH free radical up to 88.9%. Results of this study proved that the silver nanoparticles produced by polyethylene glycol possess antimicrobial and antioxidant activity

Molecular characterisation of grouper iridovirus isolates from Peninsular Malaysia

Grouper Iriovirus (GIV) is one of the most devastating viral diseases of marine and cultured groupers worldwide. In the current study, 5 presumptive Malaysian GIV isolates were characterised through PCR amplification of the major capsid protein (MCP) gene and phylogenetic analysis of the sequences. The sequences from the five GIV isolates showed 100% homology with each other and a close relationship with grouper iridovirus isolate (GIV_Tn_352), which was clustered in group 1 together with King grouper iridovirus isolate (KGIV_Cy_346), Singapore grouper iridovirus (SGIV), and Crimson snapper iridovirus isolate (CSIV). The phylogenetic tree also showed different degree of relatedness with other Ranavirus strains which were obtained from the blast of GIV MCP gene in the NCBI database. This study confirmed the GIV isolates from Malaysia are related to other isolates that were reported previously