Enhancing herbicides sorption in sodic soils through biochar amendment : A promising approach for sustainable agriculture

This study is essential for assessing the binding capacity of Prosopis wood biochar to commonly used herbicides, Pretilachlor and Pendimethalin. Understanding their sorption dynamics at varying biochar application rates and exposure times is crucial for sustainable and effective herbicide management in intensively farming agricultural fields and for reducing environmental contamination. The Prosopis wood biochar was produced in an earthen kiln at 300-350°C. The batch experiment was conducted to study the sorption potential of biochar additions at rates of 0, 5, and 10 t ha-1. The herbicides were added to the homogenized soil-biochar mixes at zero, whole, twice, and four times the recommended dose. The sorption of the herbicides by soil biochar mixture was studied for 12 and 24 hours. The result showed that Pendimethalin sorption increased with biochar application rate, requiring 24 hours for 95% sorption at 4X dose without biochar (77.95 mg/kg soil) and 12 hours with 10 t/ha biochar (75.82 mg/kg soil). The Kd value increased with biochar application (0.57-77.95 mg/kg soil) and decreased with pendimethalin application (77.95-3.04 mg/kg soil). Maximum sorption (95%) was attained within 12 hours for 1X and 2X rates and 24 hours for 4X rates when biochar was added. This demonstrated that although pendimethalin residue in the soil can be immobilized by adding biochar within 8 hours at lower rates, more than 24 hours were required when pendimethalin was applied at higher rates or repeatedly. Biochar can be used to reduce pendimethalin leaching in agricultural fields, especially sodic soils, at higher application rates.

THE DNA DAMAGE RESPONSE IN TP53 DEFICIENCY

The DNA Damage Response (DDR) is an evolutionarily conserved network of proteins that maintain genome stability in cells and serve as an anti-cancer barrier. The DDR is activated in early pre-neoplastic lesions and is often dysregulated or functionally deficient in late-stage neoplasia. The signaling and repair arms of the DDR pathways can serve as both cancer drivers and as important therapeutic targets. The following work is divided into two parts: (1) how altered double strand break repair pathways may serve as therapeutic targets for restoring sensitivity to DNA damaging agents in cancers and (2) the role of Mre11-Rad50-Nbs1 (MRN) complex, the first-responder to DNA double strand breaks, in pre-neoplastic lesions as a key cell-cycle regulator. TP53 deficiency has long been associated with poor patient outcomes and decreased response to DNA damaging agents, specifically radiotherapy. Chapter 2 of this dissertation identifies hyperactive end-joining pathways as a significant mediator of radio-resistance. We show that p53-deficiency in an isogenic model system is sufficient to induce resistance to radiation. The resistance to therapy can be partially reversed with inhibition of DNA Protein Kinase (DNA-PK), a serine-threonine regulatory kinase involved in Non-Homologous End Joining. Further, we identify a potential resistance pathway that a subset of p53-deficient cells with inhibition of DNA-PK may employ to avoid cell-death. Finally, we suggest that dual-suppression of DNA-PK and Polymerase Theta may be a clinically relevant mechanism to restore treatment sensitivity in p53-deficient cancers. Our data show that repair of S phase DNA damage by hyperactive end-joining repair pathways mediates therapeutic resistance in p53-deficient cells. The MRN complex binds to DNA DSBs, activates master signaling kinases, and initiates end resection at the break to begin repair. Data in this dissertation demonstrate that the MRN complex regulates a p53-independent, G2/M checkpoint in response to burgeoning replication stress during oncogenesis. This checkpoint response regulates mitotic entry of under-replicated DNA, enabling cells with genome instability to exit the cell-cycle via permanent G2 arrest or by mitotic catastrophe. This checkpoint response provides insight into how the DDR restrains genome instability during oncogenesis.Doctor of Philosoph

Abrazivní povrchová úprava dílů SLM M300 vyrobených z panenského prášku

This diploma thesis explores the effectiveness of abrasive surface finishing technique on SLM (Selective Laser Melting) manufactured M300 maraging steel parts using virgin powder. The study investigates various abrasive methods to determine the optimal finishing process that enhances the surface quality of 3D printed parts. The experimental setup involved applying different abrasive finishing techniques to the SLM-produced M300 parts and measuring the resulting surface roughness and morphology changes. Technique such as centrifugal tumbling were analysed to evaluate their efficiency in reducing surface irregularities and improving wear resistance, the topography images were checked as well as the morphology of tumbled samples also were investigated, Chemical composition and surface wettability were also calculated. The thesis concludes with recommendations for the industrial application of these techniques, particularly highlighting the benefits and limitations observed during the experiments. This work aims to contribute to the broader understanding of surface finishing methods for 3D printed metal parts, offering insights into their practical applications and potential improvements in surface integrity.Tato diplomová práce zkoumá účinnost techniky abrazivní povrchové úpravy na SLM (Selective Laser Melting) vyrobených dílech z martenzitické oceli M300 s použitím panenského prášku. Studie zkoumá různé abrazivní metody k určení optimálního dokončovacího procesu, který zlepšuje kvalitu povrchu 3D tištěných dílů. Experimentální uspořádání zahrnovalo aplikaci různých technik abrazivní povrchové úpravy na díly M300 vyrobené SLM a měření výsledné drsnosti povrchu a změn morfologie. Techniky, jako je odstředivé omílání, byly analyzovány, aby se vyhodnotila jejich účinnost při snižování nerovností povrchu a zlepšení odolnosti proti opotřebení, byly zkontrolovány topografické snímky a také byla zkoumána morfologie převalovaných vzorků, bylo také vypočteno chemické složení a smáčivost povrchu. V závěru práce jsou uvedena doporučení pro průmyslové využití těchto technik se zdůrazněním výhod a omezení pozorovaných během experimentů. Tato práce si klade za cíl přispět k širšímu pochopení metod povrchové úpravy 3D tištěných kovových dílů a nabídnout pohled na jejich praktické aplikace a potenciální zlepšení integrity povrchu.346 - Katedra obrábění, montáže a strojírenské metrologievýborn

Adoption Behavior of Paddy Farmers on Soil Health Card Recommendations

The study was conducted in Madurai district of Tamil Nadu to assess the adoption behavior of paddy farmers on Soil Health Card (SHC) based recommendations. A total of 120 paddy farmers who were the beneficiaries of SHC scheme were contacted to collect the data. A pre tested interview schedule was used to collect the data. The results revealed that overall adoption on SHC recommendations found to be medium (45.50%). With regard to straight fertilizers application before the introduction of SHC 40.80 percent of the respondents had applied excess NPK fertilizers. After the introduction, the excess range has been reduced up to 5.8 per cent and in the same way the deficient application was also rectified by 4.7 per cent of the farmers. With regard to complex fertilizers 12.8 per cent of the respondents had followed the exact recommendation of complex fertilizers. The adoption behavior of micronutrients showed that 29.50 per cent of respondents followed recommended dose of micronutrients after SHC scheme. About 6.00 per cent respondents had started to follow the correct dose of Bio fertilizers after the introduction of SHC. Overall adoption level of the farmers was up to medium level and hence emphasis is needed to inspire the farmers to adopt soil testing practices and soil fertility management

Clinical Comparison of Photodynamic Therapy with Methylene Blue and Malachite Green Adjunctive to Srp in Chronic Periodontitis

Chronic periodontitis is an infectious disease resulting in inflammation within the supporting tissues of the teeth, progressive attachment and bone loss. The removal of the plaque biofilm and mineralized deposits from the tooth surface are the fundamental aspects of periodontal therapy which is achieved primarily by scaling and root planing (SRP). Since mechanical therapy alone fails to eliminate bacteria that penetrate the connective tissue, the use of adjuncts to SRP has been advocated. There is evidence that local antimicrobials adjunctive to SRP provide additional benefits to the result of periodontal treatment. Photodynamic therapy (PDT) is one such approach that combines low level laser light with a photosensitizer that binds to the target cells. In the excited state, photosensitizers react with oxygen in the environment generating reactive oxygen species that cause oxidative damage to target cells. This study has shown a significant reduction in probing depth (PD) and increase in clinical attachment level (CAL) when PDT with methylene blue / malachite green was employed adjunctive to SRP. Thus, PDT can be an alternative modality for management of chronic periodontitis

Assessment of Potential Land Suitability for Tea (Camellia sinensis (L.) O. Kuntze) in Sri Lanka Using a GIS-Based Multi-Criteria Approach

The potential land suitability assessment for tea is a crucial step in determining the environmental limits of sustainable tea production. The aim of this study was to assess land suitability to determine suitable agricultural land for tea crops in Sri Lanka. Climatic, topographical and soil factors assumed to influence land use were assembled and the weights of their respective contributions to land suitability for tea were assessed using the Analytical Hierarchical Process (AHP) and the Decision-Making Trail and Evaluation Laboratory (DEMATEL) model. Subsequently, all the factors were integrated to generate the potential land suitability map. The results showed that the largest part of the land in Sri Lanka was occupied by low suitability class (42.1%) and 28.5% registered an unsuitable land cover. Furthermore, 12.4% was moderately suitable, 13.9% was highly suitable and 2.5% was very highly suitable for tea cultivation. The highest proportion of “very highly suitable” areas were recorded in the Nuwara Eliya District, which accounted for 29.50% of the highest category. The model validation results showed that 92.46% of the combined “highly suitable” and “very highly suitable” modelled classes are actual current tea-growing areas, showing the overall robustness of this model and the weightings applied. This result is significant in that it provides effective approaches to enhance land-use efficiency and better management of tea production