Preliminary assessment of the effect of waterseeding technique and herbicide application on weedy rice tillers

Metsulfuron methyl has been recommended to control weedy rice under wetseeded conditions (Zainal and Azmi, unpubl. data, 1994). Another weed control method involves broadcasting pregerminated seeds using the water-seeding technique. This study was undertaken to evaluate the effect of seeding methods and herbicide application on weedy rice tillers 45 d after sowing (DAS). A factorial experiment was carried out in a glasshouse at Putra University Malaysia. Treatment 1 (T1) was the wet-seeding method—broadcasting seed on saturated soil and introducing water up to 10-cm flooding depth 7 d after seeding with (H1) and without herbicide (H0). Treatment 2 (T2) was water seeding—continuous flooding at 10-cm depth from seeding to date of data collection with H1 and H0. All treatments were replicated five times and arranged in a factorial randomized complete block design. Both weedy rice seeds and pregerminated MR219 seeds were sown on the soil surface (Tropic Fluvaquent) into 25.5-cm-diameter × 40-cm-high experimental containers using the MARDI-recommended seed rate (500 seeds m–2) (MARDI 2004) to achieve uniform establishment. Herbicide (metsulfuron methyl 1.75% combined with bensulfuron methyl 8.25%) was applied 14 DAS at 0.05 kg ai ha–1. Water was brought in 7 DAS for treatments with herbicide (T1) to facilitate herbicide application. The effects of water seeding and herbicide application on tillering ability of weedy rice (45 DAS) were analyzed using ANOVA. The means of these treatments were compared using Duncan’s new multiple range test. Only the seeding method was significantly different at P ≤0.05. There were no significant effects or interactions for the other sources of variation tested (see table). Weedy rice tillers decreased in both seeding methods (see figure)

Spatial variability of selected forest soil properties related to carbon management in tropical lowland and montane forests

A better understanding of spatial variability of forest soil properties related to carbon (C) sequestration will improve management strategies towards conserving forest areas that project higher C stocks. This study was aimed at determining spatial variability of soil C, C:N (nitrogen) and forest floor depth in tropical lowland and montane forests at varying topographic positions. Quadrants of 10 m ×10 m were established for soil (0-15 cm depth) and forest floor sampling along three slope positions. This amounted to 120 quadrants at the montane forest and 60, in the lowland forest. Soil and forest floor samples were geo-referenced using global positioning system. Univariate statistics, including normality check, non-spatial outlier detection and data transformation were performed on test variables, followed by variography and kriging analyses to quantify spatial variability. Results showed that spatial structure of test variables differed across topographic positions and within the lowland forest. Surface maps showed distinct spatial clustering and displayed acceptable accuracy of interpolated values. Soil C stocks were highest in the summit, followed by toeslope, sideslope and Jengka Virgin Jungle Reserve. Site specific management for carbon sequestration monitoring in tropical forest should be based on topographic delineation

Carbon stocks in different carbon pools of a tropical lowland forest and a montane forest with varying topography

Increasing atmospheric carbon dioxide concentrations at alarming rates have triggered the need to revisit potential opportunities in conserving and monitoring carbon (C) stocks for climate change mitigation. The dynamic nature of tropical forests based on topographic variations and biomass components needs reliable estimation of forest C to support conservation and forest monitoring strategies. This study was aimed to determine C stocks of varying components (i.e. litter, soil, aboveground biomass and roots) in a tropical lowland forest and a tropical montane forest at varying topographic positions. Systematically designed 10 m × 10 m plots were established for soil (0–15 cm depth), litter and aboveground biomass sampling along three slope positions at the montane forest and one plot in the lowland forest due to minimal topographic variability. Basic soil characteristics and botanical distribution of both forest sites were determined. Carbon stocks were significantly higher in the tropical montane forest, where litter and soil C stocks at the summit were three and five folds significantly higher compared with the lowland forest. No significant differences were found in vegetation structure (mean diameter at breast height, mean height and stand basal area) but the aboveground biomass ranged from 100 to 120 Mg C ha-1 and was the most dominant pool (> 40%) for all sites. Soil C pools were comparable (100 to 120 Mg C ha-1) with aboveground biomass pools at the summit and toeslope position of the montane forest

Advanced Computer Technologies in Enhancing New Energy Vehicles

The development of the new energy vehicle (NEV) industry is rapid, which has greatly promoted the progress of automotive technology through computer systems. In this paper, the potential nuclear effects of computer technology on NEVs are explored. This report analyses the development and comparative analysis of five key areas: Battery Management Systems (BMS), Charging Management Systems (CMS), autonomous driving technology, fault diagnosis systems, and intelligent control mechanisms. Utilising sophisticated algorithms, artificial intelligence (AI), machine learning and big data analytics allows these systems to reduce energy consumption, better vehicle performance, and prolong battery life. Finally, the paper considers those innovations as being crucial for advancements in NEV technology, such as Vehicles Diagnostics & Training using Virtual Reality (VR) and energy storage via Vehicle-to-Grid (V2G) Technology. Additionally, this paper highlights the importance of fault diagnosis systems to ensure vehicle reliability and minimise downtime. Key future suggestions pertain to a deeper AI use for intelligent decisions, the development of ultra-fast charging solutions and cybersecurity improvements to safeguard connected vehicles. This underscores the changing effect of computer technology on the NEV industry and suggests directions for future research to help it adapt and prosper.&nbsp

Innovations and Challenges in Soft Robotic Dynamics: Advanced Modeling, Interaction, and Control Mechanisms

Soft robots are a rapidly growing field of robotics that uses compliant and deformable materials to create systems that can have differently shaped adaptive forces in unstructured environments. Because they are self-contained and inherently safe for human-robot interaction, these robots have potentially wide applications, including medical devices, industrial automation, machine inspection equipment, or environmental monitoring. Nevertheless, soft robots present unique challenges in design and control, especially when it comes to dynamic modeling and real-time control, given their infinite degrees of freedom, non-linear material response behavior, and complex interactions with the environment. In this paper, we review the methods of structural models; these include finite element methods (FEM), piecewise constant curvature (PCC) models, Cosserat rod theory, and mass-spring-damping model, with various trade-offs between computational expense and accuracy. We also dive into interaction simulation techniques, FSI, and contact mechanics, as well as actuation driven by magnetic and electric fields. This work discusses crucial concerns associated with computationally efficient, real-time control, material durability, and the unpredictability of environmental conditions. An integrated review of the future perspectives for more robust, efficient, and versatile soft robotics is presented.&nbsp

A universal description for the experimental behavior of salt-(in)dependent oligocation-induced DNA condensation

We report a systematic study of the condensation of plasmid DNA by oligocations with variation of the charge, Z, from +3 to +31. The oligocations include a series of synthetic linear ε-oligo(l-lysines), (denoted εKn, n = 3–10, 31; n is the number of lysines equal to the ligand charge) and branched α-substituted homologues of εK10: εYK10, εLK10 (Z = +10); εRK10, εYRK10 and εLYRK10 (Z = +20). Data were obtained by light scattering, UV absorption monitored precipitation assay and isothermal titration calorimetry in a wide range concentrations of DNA and monovalent salt (KCl, CKCl). The dependence of EC50 (ligand concentration at the midpoint of DNA condensation) on CKCl shows the existence of a salt-independent regime at low CKCl and a salt-dependent regime with a steep rise of EC50 with increase of CKCl. Increase of the ligand charge shifts the transition from the salt-independent to salt-dependent regime to higher CKCl. A novel and simple relationship describing the EC50 dependence on DNA concentration, charge of the ligand and the salt-dependent dissociation constant of the ligand–DNA complex is derived. For the ε-oligolysines εK3–εK10, the experimental dependencies of EC50 on CKCl and Z are well-described by an equation with a common set of parameters. Implications from our findings for understanding DNA condensation in chromatin are discussed

Chromatin and epigenetics: current biophysical views

Recent advances in high-throughput sequencing experiments and their theoretical descriptions have determined fast dynamics of the "chromatin and epigenetics" field, with new concepts appearing at high rate. This field includes but is not limited to the study of DNA-protein-RNA interactions, chromatin packing properties at different scales, regulation of gene expression and protein trafficking in the cell nucleus, binding site search in the crowded chromatin environment and modulation of physical interactions by covalent chemical modifications of the binding partners. The current special issue does not pretend for the full coverage of the field, but it rather aims to capture its development and provide a snapshot of the most recent concepts and approaches. Eighteen open-access articles comprising this issue provide a delicate balance between current theoretical and experimental biophysical approaches to uncover chromatin structure and understand epigenetic regulation, allowing free flow of new ideas and preliminary results

Spatial variability of forest floor thickness for estimation of refined carbon stocks in a tropical montane forest

Spatial variations of forest floor thickness in tropical montane forest influences carbon stocks estimates in forest floor and soil, microbial decomposition and soil conservation. Delineation of forest floor thickness according to decomposing layers (litter, hemic, sapric) and total forest floor will provide refined measurements of forest floor carbon stocks to improve site-specific carbon management. This study was aimed at determining spatial variability of the depths of decomposing forest floor layers in a tropical montane forest at varying topography. Sampling grids (10 m × 10 m) were established along three slope positions (summit, sideslope and toeslope) with 120 quadrants and their depths measured. Forest floor samples were georeferenced using a global positioning system. Variables were first explored using univariate statistics, including normality check, non-spatial outlier detection and data transformation. Variography and kriging analyses were used to quantify spatial variability of forest floor depths. Results showed that spatial structure of test variables differed across topographic positions. The coefficient of variation for test variables ranged from 27 to 64%. Surface maps displayed distinct spatial clustering and acceptable accuracy of interpolated values. Hemic and total forest floor were highest at the toeslope where hemic constituted approximately 80% of total forest floor. Site-specific management of forest floor carbon stocks in tropical montane forest should be based on topographic delineation