Biology subjects

Sarma, M.

Publications and source records attributed to Sarma, M..

3 recordsLinked to original sources

bioRxiv2025

OmniShim - a vendor-independent B0 Shimming software toolbox

PurposeTo introduce the OmniShim Toolbox, a software package designed to calibrate and perform B0 shimming in user-defined regions of interest across systems from different vendors, supporting various shim orders. MethodsIn this study, we systematically compared the performance of vendor-implemented B0 shim routines with our custom developed OmniShim toolbox, designed to improve static magnetic field homogeneity. Single-voxel magnetic resonance spectroscopy (MRS) data were acquired from the prefrontal cortex and occipital lobe, while magnetic resonance spectroscopic imaging (MRSI) data were collected from regions above and below the corpus callosum in healthy volunteers. Measurements were conducted on both 3T and 7T MR systems to evaluate the robustness and scalability of each B0 shimming strategy across different field strengths. Additionally, functional MRI (fMRI) data were acquired at 7T to assess the impact of improved shimming on EPI data quality and BOLD contrast. ResultsThe OmniShim Toolbox demonstrated superior B0 homogeneity across all applications and field strength, leading to reduced signal dropout in fMRI and MRSI data, significantly improved spectral linewidths in SV MRS and MRSI data as well improved detection of neural networks by resting state fMRI. ConclusionThe proposed OmniShim Toolbox offers a robust and flexible approach to control B0 inhomogeneity, resulting in substantial improvements in image quality and spectral resolution. These enhancements benefit a broad range of MR applications.

bioengineering↗

bioRxiv2024

BaYaka mothers balance childcare and subsistence tasks during collaborative foraging in Congo Basin

Across cultures, mothers face trade-offs between childcare and other labor. In hunter-gatherer societies, mothers face this choice on a daily basis when deciding either to take infants on foraging trips or to leave them with caregivers in the village. Yet, it remains unclear how the presence of infants in foraging groups constrains mothers mobility during foraging. Here, we present GPS, energy expenditure and food returns data of 359 foraging trips of 23 BaYaka mothers in the Republic of the Congo. We find that mothers spent more time on out-of-village foraging activities when they took infants along, compared to when they left infants behind. However, infant presence in foraging groups does not affect mothers travel distance, travel range, energy expenditure or food returns. Regardless of infant presence, women travel longer and further in a larger area when foraging in groups, compared to when foraging alone, especially in groups with more adults, females and both kin and non-kin. Our results suggest that BaYaka mothers develop ways to accommodate childcare with foraging activities by combining individual-level and group-level behavioural strategies. Our study highlights that group foraging may allow mothers with infants to maintain high mobility, which may have been a key to human range expansion.

ecology↗

bioRxiv2021

Native MOWChIP-seq: Genome-wide profiles of key protein bindings reveal functional differences among various brain regions

Genome-wide profiling of interactions between genome and various functional proteins is critical for understanding regulatory processes involved in development and diseases. Conventional assays require a large number of cells and high-quality data on tissue samples are scarce. Here we optimized a low-input chromatin immunoprecipitation followed by sequencing (ChIP-seq) technology for profiling RNA polymerase II (Pol II), transcription factor (TF), and enzyme binding at the genome scale. The new approach, termed native MOWChIP-seq, produces high-quality binding profiles using 1000-50,000 cells. We used the approach to examine the binding of Pol II and two TFs (EGR1 and MEF2C) in cerebellum and prefrontal cortex of mouse brain and found that their binding profiles are highly reflective of the functional differences between the two brain regions. Our analysis reveals the potential for linking genome-wide TF or Pol II profiles with neuroanatomical origins of brain cells.

genomics↗