Phosphorylation on PstP controls cell wall metabolism and antibiotic tolerance in Mycobacterium smegmatis [preprint]

The mycobacterial cell wall is a dynamic structure that protects Mycobacterium tuberculosis and its relatives from environmental stresses. Modulation of cell wall metabolism under stress is thought to be responsible for decreased cell wall permeability and increased tolerance to antibiotics. The signaling pathways that control cell wall metabolism under stress, however, are poorly understood. Here, we examine the signaling capacity of a cell wall master regulator, the Serine Threonine Phosphatase PstP, in the model organism Mycobacterium smegmatis. We studied how interference with a regulatory phosphorylation site on PstP affects growth, cell wall metabolism and antibiotic tolerance. We find that a phospho-mimetic mutation, pstP T171E, slows growth, misregulates both mycolic acid and peptidoglycan metabolism in different conditions, and interferes with antibiotic tolerance. These data suggest that phosphorylation on PstP controls its substrate specificity and is important in the transition between growth and stasis

Memory-Immersed Collaborative Digitization for Area-Efficient Compute-in-Memory Deep Learning

This work discusses memory-immersed collaborative digitization among compute-in-memory (CiM) arrays to minimize the area overheads of a conventional analog-to-digital converter (ADC) for deep learning inference. Thereby, using the proposed scheme, significantly more CiM arrays can be accommodated within limited footprint designs to improve parallelism and minimize external memory accesses. Under the digitization scheme, CiM arrays exploit their parasitic bit lines to form a within-memory capacitive digital-to-analog converter (DAC) that facilitates area-efficient successive approximation (SA) digitization. CiM arrays collaborate where a proximal array digitizes the analog-domain product-sums when an array computes the scalar product of input and weights. We discuss various networking configurations among CiM arrays where Flash, SA, and their hybrid digitization steps can be efficiently implemented using the proposed memory-immersed scheme. The results are demonstrated using a 65 nm CMOS test chip. Compared to a 40 nm-node 5-bit SAR ADC, our 65 nm design requires $\sim$25$\times$ less area and $\sim$1.4$\times$ less energy by leveraging in-memory computing structures. Compared to a 40 nm-node 5-bit Flash ADC, our design requires $\sim$51$\times$ less area and $\sim$13$\times$ less energy

Antibacterial and Anti-Inflammatory Activities of <i>Thymus vulgaris</i> Essential Oil Nanoemulsion on Acne Vulgaris

Antibiotics are frequently used in acne treatment and their prolonged use has led to an emergence of resistance. This study aimed to investigate the use of natural antimicrobials as an alternative therapy. The antimicrobial and anti-inflammatory activities of five commonly used essential oils (EOs) (tea tree, clove, thyme, mentha and basil EOs), and their possible mechanisms of action against Cutibacterium acnes and Staphylococcus epidermidis, were explored. The effect of the most potent EO on membrane permeability was elucidated and its anti-inflammatory action, when formulated as nanoemulsion, was tested in an in vivo acne model. The in vitro studies showed that thyme EO had the most potent antimicrobial and antibiofilm activity, with phenolics and terpenoids as main antimicrobial constituents of EO. Thyme EO affected cell membrane permeability of both bacterial species, evident by the detection of the leakage of intracellular ions and membrane integrity by the leakage of nucleic acids. Morphological alteration in bacterial cells was confirmed by transmission electron microscopy. Thyme EO nanoemulsion led to the suppression of an inflammatory response in acne animal models along with a bacterial load decrease and positive histopathological changes. Collectively, thyme EO nanoemulsion showed potent antimicrobial and anti-inflammatory effects compared to the reference antibiotics, suggesting its effectiveness as a natural alternative in acne treatment

LibraryCarpentry/lc-shell: Library Carpentry: Introduction to the Shell for librarians, June 2019

Library Carpentry lesson to learn how to use the Shell

swcarpentry/shell-novice: Software Carpentry: the UNIX shell, June 2019

Software Carpentry lesson on how to use the shell to navigate the filesystem and write simple loops and scripts