Extraction Of Nanocellulose And Characterization Of Migration Behaviour For Poly(Lactic Acid) Nanocellulose Silver Nanocomposite

The objectives of this research is to study the effect of concentration of phosphoric acid (H3PO4) on the properties of cellulose nanocrystal (PCNC), examine the effect of PCNC on the properties of poly(lactic acid) PLA nanocomposites as well as the migration behaviour of silver (Ag) from PLA/PCNC/Ag nanocomposites . Three different concentrations of H3PO4 were utilized (i.e., 5M, 8M and 11M) to extract PCNC from sugarcane bagasse. The properties of the PCNC were determined by Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). TEM results showed that the aspect ratio of PCNC was reduced as the increasing concentration of the H3PO4. The aspect ratio of PCNC isolated by 5M H3PO4 was 45 and reduced to 39 when the H3PO4 was increased to 8M. The self-interaction of PCNC was induced by the P-O-P linkages (evidenced from FTIR and XPS results). XRD results showed that increased H3PO4 concentration increased the crystallinity index of the PCNC. The crystallinity index and crystal size of the PCNC was increased from 61.7 to 69.0 and 3.68 to 5.36 respectively, when the acid concentration was increased from 5M to 11M. The effect of PCNC on mechanical and thermal properties on the PLA nanocomposites was determined by using tensile test and Differential Scanning Calorimetry (DSC). The tensile modulus and strength of PLA was slightly increased by incorporation of PCNC (synthesized using 5M H3PO4). The degree of crystallinity of PLA shows highest increment which was about 51% by the addition of PCNC isolated from 5M H3PO4. The overall and specific migration test of PLA/PCNC/Ag was performed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), respectively. The migration studies show none of the PLA nanocomposites were exceeding overall migration limit (60 mg kg-1) and specific migration limit (0.05 mg kg-1). Nonetheless, it was found that the PCNC can acts as carrier for Ag from the PLA nanocomposites and this influencing the migration behaviour of the Ag nanoparticle

Extraction Of Nanocellulose From Sugarcane Bagasse Using Different Acids And Its Effects On Poly(Lactic Acid)

The usage of abundant sugarcane bagasse as a source for the extraction of cellulose nanocrystals (CNC) would reduce waste in the environment. Strong acid hydrolysis by sulphuric acid (H2SO4) was a common method to produce CNC but the negative charged sulphate group on the surface of CNC had reduced the thermal properties and caused poor compatibility with poly(lactic acid) (PLA). This present study is to determine the feasibility of utilizing mild acid, phosphoric acid (H3PO4) to produce better thermal properties of CNCs and improved its compatibility with PLA. In this study, CNCs was extracted from sugarcane bagasse through alkaline treatment followed by acid hydrolysis. The obtained CNCs were then incorporated in PLA matrix to produce nanocomposite by solution casting method. The surface characteristics and thermal properties of different acid derived CNCs and the PLA/CNC nanocomposite were determined. The X-ray Photoelectron Spectroscopy (XPS) result showed that S-CNC (CNC by H2SO4 hydrolysis) was having slightly higher oxygen/carbon (O/C) ratio than P-CNC (CNC by H3PO4 hydrolysis). The particle size of P-CNC was smaller than S-CNC, however, the zeta potential of S-CNC is higher than P-CNC. The Fourier Transform Infra-Red Spectroscopy (FTIR) result indicated that PLA/P-CNC-10 gave better compatibility compared to PLA/S-CNC-10 nanocomposites. The degree of crystallinity (Xc) of PLA/P-CNC-10 is higher than the PLA/S-CNC-10. Thermogravimetric Analysis (TGA) results indicate that P-CNC could increase the thermal stability of PLA/P-CNC-10 nanocomposites

Whole‑Genome Sequencing of Pseudomonas koreensis Isolated from Diseased Tor tambroides

Unlike environmental P. koreensis isolated from soil, which has been studied extensively for its role in promoting plant growth, pathogenic P. koreensis isolated from fish has been rarely reported. Therefore, we investigated and isolated the possible pathogen that is responsible for the diseased state of Tor tambroides. Herein, we reported the morphological and biochemical characteristics, as well as whole-genome sequences of a newly identified P. koreensis strain. We assembled a high-quality draft genome of P. koreensis CM-01 with a contig N50 value of 233,601 bp and 99.5% BUSCO completeness. The genome assembly of P. koreensis CM-01 is consists of 6,171,880 bp with a G+C content of 60.5%. Annotation of the genome identified 5538 protein-coding genes, 3 rRNA genes, 54 tRNAs, and no plasmids were found. Besides these, 39 interspersed repeat and 141 tandem repeat sequences, 6 prophages, 51 genomic islands, 94 insertion sequences, 4 clustered regularly interspaced short palindromic repeats, 5 antibiotic-resistant genes, and 150 virulence genes were also predicted in the P. koreensis CM-01 genome. Culture-based approach showed that CM-01 strain exhibited resistance against ampicillin, aztreonam, clindamycin, and cefoxitin with a calculated multiple antibiotic resistance (MAR) index value of 0.4. In addition, the assembled CM-01 genome was successfully annotated against the Cluster of Orthologous Groups of proteins database, Gene Ontology database, and Kyoto Encyclopedia of Genes and Genome pathway database. A comparative analysis of CM-01 with three representative strains of P. koreensis revealed that 92% of orthologous clusters were conserved among these four genomes, and only the CM-01 strain possesses unique elements related to pathogenicity and virulence. This study provides fundamental phenotypic and genomic information for the newly identified P. koreensis strain

Non-Standard Errors

In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty: Non-standard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for better reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants

Sustainability Framing of Controlled Environment Agriculture and Consumer Perceptions: A Review

The ongoing criticism of conventional agricultural activities being unsustainable in the face of climate change and global population growth has been one of the key drivers for technological innovation in this space. Controlled Environment Agriculture (CEA), especially in the high-tech form of vertical farming, as a new agri-food technology, has been positioned as a sustainable solution to the dilemma of feeding the world and preserving the planet. Acknowledging sustainability as a multi-dimensional concept encompassing environmental, economic, social, and cultural aspects, this review briefly outlines the evolving meaning of sustainability, and how CEA has been framed as sustainable in the literature. Specifically, the review examines studies that have investigated consumer perceptions and acceptance of CEA and discussed how sustainability features of CEA were presented to consumers in a diverse way across these studies. The review highlights that the social and cultural dimensions of sustainability were largely neglected not only in research that focused on the development of CEA, but also in the exploration of consumers’ perceptions of CEA. A more holistic examination of the sustainability of CEA and a comprehensive understanding from consumers is important for transitioning towards more sustainable production systems enabled by new technologies such as CEA

Tailoring Chemical, Physical, and Morphological Properties of Sugarcane Bagasse Cellulose Nanocrystals via Phosphorylation Method

In this work, three different concentrations of phosphoric acid (H3PO4) were used (i.e. 5 M, 8 M, and 11 M) to isolate cellulose nanocrystals (hereafter labeled as 5-PCNC, 8-PCNC and 11-PCNC, respectively) from sugarcane bagasse. The PCNC was analyzed using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). From TEM and XRD results, it was found that the morphology and crystallinity index of the PCNC was influenced by the different concentration of phosphoric acid. FTIR and XPS results indicate that self-interaction of CNC occurs via P–O–P linkages. These data are important for PCNC selection in application; one may consider the aspect ratio (5-PCNC could be a good choice); while other may require higher crystallinity index (8-PCNC and 11-PCNC could be a good candidate)

Complete chloroplast genome data of Shorea macrophylla (Engkabang): Structural features, comparative and phylogenetic analysis

Shorea macrophylla belongs to the Shorea genus under the Dipterocarpaceae family. It is a woody tree that grows in the rainforest in Southeast Asia. The complete chloroplast (cp) genome sequence of S. macrophylla is reported here. The genomic size of S. macrophylla is 150,778 bp and it possesses a circular structure with conserved constitute regions of large single copy (LSC, 83,681 bp) and small single copy (SSC, 19,813 bp) regions, as well as a pair of inverted repeats with a length of 23,642 bp. It has 112 unique genes, including 78 protein-coding genes, 30 tRNA genes, and four rRNA genes. The genome exhibits a similar GC content, gene order, structure, and codon usage when compared to previously reported chloroplast genomes from other plant species. The chloroplast genome of S. macrophylla contained 262 SSRs, the most prevalent of which was A/T, followed by AAT/ATT. Furthermore, the sequences contain 43 long repeat sequences, practically most of them are forward or palindrome type long repeats. The genome structure of S. macrophylla was compared to the genomic structures of closely related species from the same family, and eight mutational hotspots were discovered. The phylogenetic analysis demonstrated a close relationship between Shorea and Parashorea species, indicating that Shorea is not monophyletic. The complete chloroplast genome sequence analysis of S. macrophylla reported in this paper will contribute to further studies in molecular identification, genetic diversity, and phylogenetic research