Adaptive Mechanism Research Articles

Attitude control of UAV bicopter using adaptive LQG

This paper aims to design a controller that is able to maintain the stability of the unmanned aerial vehicle (UAV) bicopter attitude when carrying a payload. When the value of the payload inertia is in uncertainty, it is necessary to design a controller that can carry out the adaptation process. This paper proposes an Linear Quadratic Gaussian (LQG) adaptive controller to control the attitude of the bicopter with uncertain payload conditions. The proposed adaptive mechanism is a development of LQG control that can follow the response of the reference model. The success of LQG adaptive control is tested by providing uncertain payload parameters. The simulation results show that the LQG adaptive controller successfully overcomes the influence of inertial disturbances originating from the payload. There is a gain ρ in the LQG adaptive mechanism, this gain is influenced by the parameter σ which acts as a learning rate that produces a response to adapt to the response of the reference model. From the test results obtained when the value of σ is enlarged there is an increased overshoot condition/value but the root mean square error (RMSE) value decreases. That means when the RMSE decreases, the response is getting closer to the model reference. To reduce the overshoot effect of increasing the value of σ, an improvement is made in the search for the gain value of ρ. From the test results, the value of σ=1 was chosen with the development of the gain equation ρ.

Marine Bacteria: A Source of Novel Bioactive Natural Products.

Marine natural products have great pharmacological potential due to their unique and diverse chemical structures. The marine bacterial biodiversity and the unique marine environment lead to a high level of complexity and ecological interaction among marine species. This results in the production of metabolic pathways and adaptation mechanisms that are different from those of terrestrial organisms, which has drawn significant attention from researchers in the field of natural medicine. This review provides an analysis of the distribution and frequency of keywords in the literature on marine bacterial natural products as well as an overview of the new natural products isolated from the secondary metabolites of marine bacteria in recent years. Finally, it discusses the current research hotspots in this field and speculates on future directions and limitations.

Discovery and characterization of temperature adaptation modules by mining L-glutamate decarboxylase derived from psychrophilic microorganisms

Directed alterations of the enzyme's temperature adaptations, such as thermostability and optimal catalytic temperature (Topt), are usually the way to go in order to meet the applications, however they are limited by the understanding between protein structure and function. Glutamate decarboxylase (GADs) is a common enzyme in the food industry. In this study, we identified and characterized three novel L-glutamate decarboxylases from psychrophilic microorganisms. Interestingly, the two enzymes (Gad Psy.Y/Gad Psy.F) showed significant differences in temperature adaptation. Through multiple sequence alignment and structural analysis, two potential regions that may affect the Topt and thermostability of the GAD, termed temperature adaptation modules (TAMs), were targeted. To validate the role of TAMs, we constructed mutants with bi-directional transplants of TAMs, which ultimately significantly altered the temperature adaptation of Gad Psy.Y and Gad Psy.F. Molecular dynamics simulations analysis demonstrated that the introduction and disruption of salt bridges in the mutant TAMs are crucial for this alteration. These findings deepen the understanding of the mechanisms of protein temperature adaptation and provide implications for protein engineering, while also offering advantageous enzymes to support the biosynthesis of GABA.

Enhancing intrusion detection in next-generation networks based on a multi-agent game-theoretic framework

<span lang="EN-US">With cyber threats becoming increasingly sophisticated, existing intrusion detection systems (IDS) in next generation networks (NGNs) are subjected to more false-positives and struggles to offer robust security feature, highlighting a critical need for more adaptive and reliable threat detection mechanisms. This research introduces a novel IDS that leverages a dueling deep Q-network (DQN) a reinforcement learning algorithm within game-theoretic framework simulating a multi-agent adversarial learning scenario to address these challenges. By employing a customized OpenAI Gym environment for realistic threat simulation and advanced dueling DQN mechanisms for reduced overestimation bias, the proposed scheme significantly enhances the adaptability and accuracy of intrusion detection. Comparative analysis against current state-of-the-art methods reveals that the proposed system achieves superior performance, with accuracy and F1-score improvements to 95.02% and 94.68%, respectively. These results highlight the potential scope of the proposed adaptive IDS to provide a robust defense against the dynamic threat landscape in NGNs.</span>

Adaptive learning-based hybrid recommender system for deception in Internet of Thing

In the rapidly evolving Internet of Things (IoT) security domain, device vulnerabilities pose significant risks, frequently exploited by cyberattackers. Traditional reactive security measures like patching often fall short against advanced threats. This paper introduces a proactive deception system enhanced by an innovative Adaptive Learning-based Hybrid Recommender System (AL-HRS), utilizing the vulnerability and attack repository for IoT (VARIoT) database. This advanced system identifies existing vulnerabilities and dynamically recommends additional deceptive vulnerabilities based on real-time analysis of attacker behavior and historical exploit data. These recommended vulnerabilities mislead attackers into engaging with controlled environments such as honeypots, effectively neutralizing potential threats. The AL-HRS combines the predictive strengths of content-based filtering (CBF) and collaborative filtering (CF) with an adaptive learning mechanism that adjusts recommendations based on ongoing attacker interactions, ensuring the system’s efficacy amidst changing attack patterns. Our approach innovatively combines these methodologies to provide a continuously evolving security strategy, significantly enhancing the deception capability of IoT systems. Initial evaluations demonstrate a potential reduction in device compromise, highlighting the effectiveness and strategic relevance of this adaptive deception framework in IoT cybersecurity.

Mitigating salt stress in “Friariello Napoletano” (Brassica rapa subsp. sylvestris L. Janch. var. esculenta Hort.): The potential of biochar for sustainable agriculture

The agricultural sector is therefore called upon to seek efficient and sustainable strategies to improve plant resilience and tolerance to sub-optimal growth conditions. In many coastal areas of the Mediterranean, saline stress causes serious problems to vegetable crops. In this scenario, the use of upgraded agrochemicals such as plant biostimulants, biochar and plant nutrition regulators could be beneficial. The aim of the study was to evaluate the effects of amending the soil with different concentrations of poplar-derived biochar (0 %, 1 % and 2 % by volume), on the productive and qualitative response of an ecotype of “Friariello Napoletano” (Brassica rapa subsp. sylvestris L. Janch. var. esculenta Hort.) under different levels of saline irrigation (0, 30, 60 and 120 mM NaCl, giving an electrical conductivity values of 0.05, 2.09, 6.09 and 9.70 dS m–1). The experiment was conducted in an unheated greenhouse, using pot plants grown in soil with a randomized complete-block experimental design arranged in a 4 × 3 factorial scheme with three replications. Productive and physiological results (ACO2, gs, E, SPAD index) highlighted a highly glycophytic response of Friariello. Biochar integration, besides increasing total production and glucosinolate content, led to a significant reduction in toxic ion content (Na+and Cl−) under saline conditions compared to control plants. Regardless of salinity effect, the application of biochar resulted in an increase in fresh yield and photosynthetic activity (ACO2) of 12.8 % and 29.3 % respectively. The promising results underscore the potential role of biochar as a sustainable strategy for mitigating salt stress in Friariello Napoletano and potentially other vegetable crops in salt-affected regions. However, it needs to be clarified which adaptive mechanisms triggered by biochar improves production performance even and especially under sub-optimal growing conditions.

Chromosome-scale assembly and analysis of yellow Camellia (Camellia limonia) genome reveal plant adaptation mechanism and flavonoid biosynthesis in karst region

Yellow Camellia is an endangered and protected wild plant with unique medicinal value. Among the Camellia Sect. Chrysantha Chang, certain species (e.g. Camellia limonia) can grow in karst regions. The karst region is a highly sensitive ecosystem with low environmental capacity. However, the molecular mechanisms underlying the adaptation of yellow camellia to karst regions remain unclear. Here, we present a high-quality genome with 15 chromosome groups with an N50 of 198.92Mb. The divergence between C. limonia and Camellia sinensis occurred approximately 6 million years ago, indicating that the Himalayan uplift event may led to species differentiation. This enables C. limonia to thrive in a unique ecological environment like the karst region. Flavonoid compounds play a significant role in the interaction between plants and their environment. In comparison to Theaceae family genomes, C. limonia exhibits an increased number of gene family members involved in the flavonoid biosynthesis pathway, including UDP-glycosyltransferases and chalcone reductase. Additionally, two gene clusters associated with flavonoid biosynthesis were identified in the genome of C. limonia. Furthermore, comparative genomics analysis revealed the expansion of genes associated with karst environment adaptation in the genome of C. limonia, such as calmodulin genes and genes related to Calcium ion transmembrane transport. Additionally, at the gene expression level, it was observed that the secondary metabolism-related genes may be involved in the calcium tolerance of C. limonia. These findings provide important insights into the evolution of C. limonia, offering references for the study of plants in karst areas.

Functional characterization of CaSOC1 at low temperatures and its role in low-temperature escape

Environmental factors such as light and temperature tightly regulate plant flowering time. Under stressful conditions, plants inhibit vegetative growth and accelerate flowering as an emergency response. This adaptive mechanism benefits the survival of species and enhances their reproductive success. This phenomenon is often referred to as stress escape. However, the signaling pathways between low-temperature signals and flowering time are poorly understood. In this study, the MIKC transcription factor, CaSOC1, was isolated from pepper (Capsicum annuum), which showed suppressed expression under low-temperature conditions. Silencing the expression of CaSOC1 in pepper plants resulted in reduced photosynthetic capacity, inhibited vegetative growth, and increased sensitivity to low temperatures. In contrast, overexpression of CaSOC1 increased the biomass of tomato plants under normal growth conditions but suppressed their antioxidant enzyme activity at low temperatures, which negatively regulated their cold tolerance. Furthermore, intermittent low-temperature treatment with CaSOC1 overexpression promoted early flowering in tomato plants. Our findings demonstrate that CaSOC1 reduced the cold tolerance of pepper plants under short term low-temperature conditions, whereas intermittent low-temperature treatment enhanced flower bud differentiation, enabling stress escape and adaptation to long low-temperature environments.

High energetic cost of color change in octopuses

For many animals, color change is a critical adaptive mechanism believed to carry a substantial energetic cost. Yet, no study to date has directly measured the energy expenditure associated with this process. We examined the metabolic cost of color change in octopuses by measuring oxygen consumption in samples of excised octopus skin during periods of chromatophore expansion and contraction and then modeled metabolic demand over the whole octopus as a function of octopus mass. The metabolic demand of the fully activated chromatophore system is nearly as great as an octopus’s resting metabolic rate. This high metabolic cost carries ecological and evolutionary implications, including selective pressures in octopuses that may influence the adoption of nocturnal lifestyles, the use of dens, the reduction of the chromatophore system in deep-sea species, and metabolic trade-offs associated with foraging.

Comparative Skeletopy of the Mammalians Lumbar Spinal Cord

The spinal cord is the most phylogenetically ancient part of the central nervous system. The more rapid growth of the spine in relation to the spinal cord in ontogenesis leads to the fact that in adult mammals some segments of the spinal cord are shifted ro strally in relation to the eponymous vertebrae, which is called ascension of the spinal cord. Based on literature data, we compared the skeletotopy of the lumbar spinal cord of 17 species of mammals. In 4 species, we also compared the skeletotopy of newborn and adult animals. The ratio of the length of the L2 segment to the length of the VL2 vertebra and the number of the vertebra in which the 29th segment of the spinal cord is located, characterizing the degree of ascension, were determined. Based on literature data, we determined characteristics frequently used in comparative studies: finger dexterity and encephalization coefficient. It has been shown that different species differ to a greater extent in the relative length of the rostral lumbar segments, and within the same species, newborns differ from adults in the relative length of the caudal lumbar segments. For most species, the degree of spinal cord ascension significantly positively correlates with finger dexterity and the encephalization coefficient. The considered macroanatomical characteristics of the spinal cord may be used to analyze the relationships between adaptive mechanisms in various mammalian species.

SmartStudy-Learning Path Recommender system using DS and ML

Learning Path Recommender Systems (LPRS) utilize machine learning and data-driven approaches to personalize educational experiences, adapting content sequences based on individual learners’ needs and progress. With the rising demand for tailored learning, LPRS have emerged as vital tools to guide students through educational content, enhancing engagement and achievement. This review covers state-of-the-art algorithms, including collaborative filtering and reinforcement learning, used in LPRS to optimize learning paths. We discuss model accuracy, user interaction data, and adaptive feedback mechanisms, providing insights into the potential of LPRS to improve learning outcomes

Structural Insights into Cold-Active Lipase from Glaciozyma antarctica PI12: Alphafold2 Prediction and Molecular Dynamics Simulation.

Cold-active enzymes have recently gained popularity because of their high activity at lower temperatures than their mesophilic and thermophilic counterparts, enabling them to withstand harsh reaction conditions and enhance industrial processes. Cold-active lipases are enzymes produced by psychrophiles that live and thrive in extremely cold conditions. Cold-active lipase applications are now growing in the detergency, synthesis of fine chemicals, food processing, bioremediation, and pharmaceutical industries. The cold adaptation mechanisms exhibited by these enzymes are yet to be fully understood. Using phylogenetic analysis, and advanced deep learning-based protein structure prediction tool Alphafold2, we identified an evolutionary processes in which a conserved cold-active-like motif is presence in a distinct subclade of the tree and further predicted and simulated the three-dimensional structure of a putative cold-active lipase with the cold active motif, Glalip03, from Glaciozyma antarctica PI12. Molecular dynamics at low temperatures have revealed global stability over a wide range of temperatures, flexibility, and the ability to cope with changes in water and solvent entropy. Therefore, the knowledge we uncover here will be crucial for future research into how these low-temperature-adapted enzymes maintain their overall flexibility and function at lower temperatures.

Transcriptional Responses of Lacticaseibacillus rhamnosus to TNFα, IL-6, IL-8, and IL-10 Cytokines

The interaction between gut microbiota and the host immune system is a complex and understudied field, with cytokines like TNFα, IL-6, IL-8, and IL-10 playing pivotal roles. Commensal bacteria, including lactobacilli, respond to these cytokines through adaptive mechanisms that support their survival and function within the gut. While the influence of cytokines on pathogenic bacteria is well documented, their impact on commensal bacteria, particularly lactobacilli, remains underexplored. This study investigates the transcriptional responses of Lacticaseibacillus rhamnosus strains K32 and R19-3 to various cytokines using next-generation RNA sequencing (RNA-seq). Our findings reveal that cytokines, especially IL-8 and IL-10, significantly alter the L. rhamnosus transcriptome, affecting genes involved in carbohydrate metabolism, stress response, and transcriptional regulation. Notably, IL-8 and IL-10 induce a significant downregulation of genes related to the phosphotransferase system, suggesting a reduction in metabolic activity in response to inflammatory signals. This study unveils a previously unexplored aspect of L. rhamnosus adaptation, highlighting its intricate response to cytokine signals. By modulating gene expression, L. rhamnosus may mitigate the adverse effects of inflammation and promote gut health. These insights could inform the development of targeted probiotic therapies for inflammatory bowel disease (IBD) and other conditions with altered cytokine levels. Our results suggest that co-evolution between a host and gut microbiota enables bacteria to respond to specific cytokines through gene expression changes, revealing a unique and underexplored facet of the interaction between commensal bacteria and the host organism.

Alterations in center-surround contrast suppression in patients with major depressive disorder.

Previous pattern electroretinogram studies indicate reduced retinal contrast gain in patients with a major depressive disorder (MDD) which may contribute to alterations in visual perception. In line, psychophysical investigations reported elevated contrast thresholds in MDD. This study aims to gain insights into higher-level processing of visual information in MDD by evaluating contrast suppression. We examined contrast suppression of 21 MDD patients and 23 healthy controls (HC) using four different stimulus conditions (spatial frequencies 6.3 and 12.6cpd at 30% and 60% background contrast) in a psychophysical test. Participants were instructed to adjust perceived contrasts between two vertical target patches, embedded in a horizontally or vertically oriented grid background. With finer stimulus gratings, MDD patients exhibited less contrast suppression compared to HC, particularly when the stimulus contrast was high (p = 0.006; MDD vs. HC = - 45%). Contrast suppression in the HC group was significantly reduced for the coarse compared to the fine grating, while contrast suppression scores in MDD did not change with the spatial properties of the stimulus. The reduced contrast suppression in patients with MDD supports the hypothesis of altered dopaminergic neurotransmission and could be attributed to alterations in the retinal receptive fields or in dysfunctional adaptation mechanisms in depression.

Adaptation mechanisms of Alcanivorax facilitating its predominance in marine environments

IntroductionAlcanivorax, a typical alkane-degrading bacterium, has demonstrated the ability to utilize inorganic electron donor in some reports. However, a comprehensive analysis of its potentiality to utilize inorganic electron donor is still lacking.MethodsIn this study, genomic and phylogenetic analyzes were used to explore the potential oxidative capacity of inorganic compounds in Alcanivorax. And its functions were verified through physiological experiments.ResultsThe sulfur oxidation-related genes sqr and tsdA are prevalent and have various evolutionary origins. Potential genes for CO oxidation were present in 39 strains, whereas genes associated with iron, hydrogen, and ammonia oxidation were either rare or absent. The physiological functions of Sqr and TsdA were confirmed in six representative strains under heterotrophic conditions. Adding thiosulfate enhanced Alcanivorax growth. However, Alcanivorax bacteria perform sulfide detoxification through Sqr rather than by gaining energy via sulfide oxidation Although no strain was confirmed to be chemoautotrophs, we discovered that the two clades, A. xenomutans and A. profundimaris, can grow under conditions with very low organic matter.DiscussionThe ability to utilize inorganic compounds as a supplementary energy source and adapt to carbon oligotrophic growth may contribute to the prevalence of Alcanivorax in marine ecosystems.

Urban expansion and agricultural land loss: a GIS-Based analysis and policy implications in Hawassa city, Ethiopia

This study investigated the historical and future trends of urban expansion and its subsequent impact on agricultural land-use in Hawassa city, Ethiopia. A time-series of remote-sensing imageries from Landsat Thematic Mapper for the years 1984, 1990, 2000, and 2010 and Operational Land Imager for 2021 were used to extract the LULC information from the study area. Seven major land-cover classes’ waterbody, built-up, agricultural land, wetland, grassland, woody vegetation, and agroforestry were identified with visual image interpretation along with supervised image classification techniques using the maximum-likelihood algorithm for the study years. The urban and agricultural lands were then extracted from the original LULC data to quantify the extent, rates, and number of area conversion between the two. The Land Change Modeler module of TerrSet software was used to predict the spatial extents of built-up and agricultural lands in 2030 and 2050. The results showed that there have been significant changes between the LULC types in Hawassa city within the past 37 years, from which built-up and agricultural land have shown the most prevalent changes. It showed that built-up land has increased from 584.73 ha in 1,984–3,939.03 ha in 2021, representing a 573.65% increase at an annual growth rate of 15.50%. However, agricultural land decreased from 8,324.64 ha to 3,595.68 ha in the respective years, with a 56.81% decrease at a rate of −1.54% each year. A total of 3,148.74 ha (37.82%) of agricultural land was converted into built-up land within the past 37 years (85.10 ha per year, a rate of 1.02%. The built-up land is projected to increase to 5,009.85 ha and 6,794.73 ha from 2021 to 2030 and 2050, with annual growth rates of 3.02% and 2.50%, respectively. In the same years, agricultural land will decrease to 2,849.58 ha and 2033.46 ha by 2.31% and 1.50% annually, respectively, from which 64.76 ha (1.80%) and 48.41 ha (1.35%) will be converted into built-up land, respectively. Future planning and development in the city should consider the rapid increase in built-up land toward agricultural land areas and develop appropriate adaptation mechanisms for the local community, which is highly dependent on agriculture.

Acute resistance exercise and training reduce desmin phosphorylation at serine 31 in human skeletal muscle, making the protein less prone to cleavage.

Desmin intermediate filaments play a crucial role in stress transmission and mechano-protection. The loss of its integrity triggers myofibril breakdown and muscle atrophy for which desmin phosphorylation (pDes) is a priming factor. We investigated whether eccentric accentuated resistance exercise (RE) influences the regulation of pDes, effecting its susceptibility to cleavage. Ten healthy persons performed 14 RE-sessions (2 per week). Muscle biopsies were collected in both untrained and trained conditions at rest (pre 1, pre 14) and one hour after RE (post 1, post 14). Western blotting and immunohistochemistry were utilized to assess desmin content, phosphorylation at several sites and susceptibility to cleavage. In untrained condition (pre 1, post 1), RE induced dephosphorylation of serin 31 and 60. Trained muscle exhibited more pronounced dephosphorylation at Serin 31 post-RE. Dephosphorylation was accompanied by reduced susceptibility of desmin to cleavage. Additionally, training increased total desmin content, upregulated baseline serine 31 phosphorylation and attenuated pDes at serine 60 and threonine 17. Our findings suggest that acute and repeated RE changes the phosphorylation pattern of desmin and its susceptibility to cleavage, highlighting pDes as an adaptive mechanism in skeletal muscle, contributing to the proteostatic regulation in response to recurring stress.

Design of a Feedforward Decoupled Current Controller and an Optimized Voltage‐Oriented Control for Bi‐Directional Power Flow for V2G Application

ABSTRACTBi‐directional power exchange between the lithium‐ion battery and the grid can be achieved using vehicle‐to‐grid (V2G) technology. Bi‐directional battery chargers for V2G applications present opportunities and challenges, as the rapid growth of active components can compromise system reliability. This paper proposes an adaptive control mechanism for a three‐phase bi‐directional battery charging system to address this. The system integrates a bi‐directional active front‐end (AFE) converter (BAC) with an interleaved buck‐boost converter to enable adaptive constant current/constant voltage (CC/CV) mode operation and bi‐directional power flow. A feedforward decoupled current controller and pulse width modulation scheme optimize battery charging, while an optimized voltage‐oriented control (OVOC) model‐based controller ensures stable bi‐directional power exchange between the electric vehicle (EV) and the utility. Experimental results validate the effectiveness of the proposed approach, with findings demonstrating low total harmonic distortion (THD), unity power factor (UPF), and minimal DC voltage ripple. A 12.5 kW prototype further confirms the practical viability of the design, offering a promising solution for enhanced reliability and performance in V2G battery chargers.

Whole-genome sequencing reveals genetic structure and adaptive genes in Nepalese buffalo breeds.

Indigenous buffaloes, as the important livestock species contributing to economy of the country, are the lifeline of livelihood in Nepal. They are distributed across diverse geographical regions of the country and have adapted to various feeding, breeding, and management conditions. The larger group of these native buffalo breeds are present in narrow and stiff hilly terrains. Their dispersal indicates a possible environmental adaptation mechanism, which is crucial for the conservation of these breeds. We utilized whole-genome sequencing (WGS) to investigate the genetic diversity, population structure, and selection signatures of Nepalese indigenous buffaloes. We compared 66 whole-genome sequences with 118 publicly available sequences from six river and five swamp buffalo breeds. Genomic diversity parameters indicated genetic variability level in the Nepalese buffaloes comparable to those of Indian breeds, and population genetic structure revealed distinct geography-mediated genetic differentiation among these breeds. We used locus-specific branch length analysis (LSBL) for genome-wide scan, which revealed a list of potentially selected genes in Lime and Parkote breeds that inhabit the hilly region. A gene ontology (GO) analysis discovered that many GO terms were associated with cardiac function regulation. Furthermore, complementary analyses of local selection signatures, tissue expression profiles, and haplotype differences identified candidate genes, including KCNE1, CSF1R, and PDGFRB, related to the regulation of cardiac and pulmonary functions. This study is a comprehensive WGS-based genetic analysis of the native Nepalese buffalo breeds. Our study suggested that the Nepalese "hilly" buffaloes, especially the Lime and Parkote breeds, have undergone some characteristic genetic changes and evolved increased cardiac and pulmonary function for their adaptation to the steep hilly terrains of the country.

Salmonella Typhi Haplotype 58 biofilm formation and genetic variation in isolates from typhoid fever patients with gallstones in an endemic setting in Kenya

Although typhoid fever has largely been eliminated in high-income countries, it remains a major global public health concern especially among low- and middle-income countries. The causative agent, Salmonella enterica serovar Typhi (S. Typhi), is a human restricted pathogen with a limited capacity to replicate outside the human host. Human carriers, 90% of whom have gallstones in their gallbladder, continue to shed the pathogen for an ill-defined period of time after treatment. The genetic mechanisms involved in establishing the carrier state are poorly understood, but S. Typhi is thought to undergo specific genetic changes within the gallbladder as an adaptive mechanism. In the current study, we aimed to identify the genetic differences in longitudinal clinical S. Typhi isolates from asymptomatic carriers with gallstones in a typhoid endemic setting in Nairobi, Kenya. Whole-genome sequences were analyzed from 22 S. Typhi isolates, 20 from stool samples, and 2 from blood samples, all genotype 4.3.1 (H58). Out of this, 19 strains were from four patients also diagnosed with gallstones, of whom three had typhoid symptoms and continued to shed S. Typhi after treatment. All isolates had point mutations in the quinolone resistance-determining region (QRDR), and only sub-lineage 4.3.1.2.EA3 encoded multidrug resistance genes. There was no variation in antimicrobial resistance patterns among strains from the same patient/household. Non-multidrug resistant (MDR) isolates formed significantly stronger biofilms in vitro than the MDR isolates, p<0.001. A point mutation within the treB gene (treB A383T) was observed in strains isolated after clinical resolution from patients living in 75% of the households. For missense mutations in Vi capsular polysaccharide genes, tviE P263S was also observed in 18% of the isolates. This study provides insights into the role of typhoid carriage, biofilm formation, AMR genes, and genetic variations in S. Typhi during asymptomatic carriage.