Design and Analysis of Soft Error Rate in FET/CNTFET Based Radiation Hardened SRAM Cell

Aerospace equipages encounter potential radiation footprints through which soft errors occur in the memories onboard. Hence, robustness against radiation with reliability in memory cells is a crucial factor in aerospace electronic systems. This work proposes a novel Carbon nanotube field-effect transistor (CNTFET) in designing a robust memory cell to overcome these soft errors. Further, a petite driver circuit to test the SRAM cells which serve the purpose of precharge and sense amplifier, and has a reduction in threefold of transistor count is recommended. Additionally, analysis of robustness against radiation in varying memory cells is carried out using standard GPDK 90 nm, GPDK 45 nm, and 14 nm CNTFET. The reliability of memory cells depends on the critical charge of a device, and it is tested by striking an equivalent current charge of the cosmic ray’s linear energy transfer (LET) level. Also, the robustness of the memory cell is tested against the variation in process, voltage and temperature. Though CNTFET surges with high power consumption, it exhibits better noise margin and depleted access time. GPDK 45 nm has an average of 40% increase in SNM and 93% reduction of power compared to the 14 nm CNTFET with 96% of surge in write access time. Thus, the conventional MOSFET’s 45 nm node outperforms all the configurations in terms of static noise margin, power, and read delay which swaps with increased write access time.

Prostate Cancer: Early Detection and Assessing Clinical Risk Using Deep Machine Learning of High Dimensional Peripheral Blood Flow Cytometric Phenotyping Data

Detecting the presence of prostate cancer (PCa) and distinguishing low- or intermediate-risk disease from high-risk disease early, and without the need for potentially unnecessary invasive biopsies remains a significant clinical challenge. The aim of this study is to determine whether the T and B cell phenotypic features which we have previously identified as being able to distinguish between benign prostate disease and PCa in asymptomatic men having Prostate-Specific Antigen (PSA) levels < 20 ng/ml can also be used to detect the presence and clinical risk of PCa in a larger cohort of patients whose PSA levels ranged between 3 and 2617 ng/ml. The peripheral blood of 130 asymptomatic men having elevated Prostate-Specific Antigen (PSA) levels was immune profiled using multiparametric whole blood flow cytometry. Of these men, 42 were subsequently diagnosed as having benign prostate disease and 88 as having PCa on biopsy-based evidence. We built a bidirectional Long Short-Term Memory Deep Neural Network (biLSTM) model for detecting the presence of PCa in men which combined the previously-identified phenotypic features (CD8+CD45RA-CD27-CD28- (CD8+ Effector Memory cells), CD4+CD45RA-CD27-CD28- (CD4+ Effector Memory cells), CD4+CD45RA+CD27-CD28- (CD4+ Terminally Differentiated Effector Memory Cells re-expressing CD45RA), CD3-CD19+ (B cells), CD3+CD56+CD8+CD4+ (NKT cells) with Age. The performance of the PCa presence ‘detection’ model was: Acc: 86.79 ( ± 0.10), Sensitivity: 82.78% (± 0.15); Specificity: 95.83% (± 0.11) on the test set (test set that was not used during training and validation); AUC: 89.31% (± 0.07), ORP-FPR: 7.50% (± 0.20), ORP-TPR: 84.44% (± 0.14). A second biLSTM ‘risk’ model combined the immunophenotypic features with PSA to predict whether a patient with PCa has high-risk disease (defined by the D’Amico Risk Classification) achieved the following: Acc: 94.90% (± 6.29), Sensitivity: 92% (± 21.39); Specificity: 96.11 (± 0.00); AUC: 94.06% (± 10.69), ORP-FPR: 3.89% (± 0.00), ORP-TPR: 92% (± 21.39). The ORP-FPR for predicting the presence of PCa when combining FC+PSA was lower than that of PSA alone. This study demonstrates that AI approaches based on peripheral blood phenotyping profiles can distinguish between benign prostate disease and PCa and predict clinical risk in asymptomatic men having elevated PSA levels.

Adoptive Transfer Immunization of Mice

This procedure is designed to enrich and expand antibody-forming cells for use in generating monoclonal antibodies. Gamma-irradiation is used to wipe out the immune system in a recipient animal, after which spleen cells that have reverted to memory cells are obtained from syngeneic donor animals and transferred to the irradiated animal, allowing the implanted immune cells to take over. This method can produce an 80-fold enrichment of antibody-producing cells over that obtained in the original immunized animal.

The Combined Effects of Cycling Endurance and TID on Floating Gate Memory Cells

In this paper, the combined effects of cycling endurance and radiation on floating gate memory cell are investigated in detail, the results indicate that: 1.The programmed flash cells with a prior appropriate number of program and erase cycling stress exhibit much smaller threshold voltage shift than their counterpart in response to radiation, which is mainly ascribed to the recombination of trapped electrons (introduced by cycling stress) and trapped holes (introduced by irradiation) in the oxide surrounding the floating gate; 2.The radiation induced transconductance degradation in prior cycled flash cell is more severe than those without cycling stress in both of the programmed state and erased state; 3. Radiation is more likely to induce interface generation in programmed state than in erased state. This paper will be useful in understanding the issues involved in cycling endurance and radiation effects as well as in designing radiation hardened floating gate memory cells.

Dependence on Bcl6 and Blimp1 drive distinct differentiation of murine memory and follicular helper CD4+ T cells

During the immune response, CD4+ T cells differentiate into distinct effector subtypes, including follicular helper T (Tfh) cells that help B cells, and into memory cells. Tfh and memory cells are required for long-term immunity; both depend on the transcription factor Bcl6, raising the question whether they differentiate through similar mechanisms. Here, using single-cell RNA and ATAC sequencing, we show that virus-responding CD4+ T cells lacking both Bcl6 and Blimp1 can differentiate into cells with transcriptomic, chromatin accessibility, and functional attributes of memory cells but not of Tfh cells. Thus, Bcl6 promotes memory cell differentiation primarily through its repression of Blimp1. These findings demonstrate that distinct mechanisms underpin the differentiation of memory and Tfh CD4+ cells and define the Bcl6–Blimp1 axis as a potential target for promoting long-term memory T cell differentiation.

RNA-Binding Protein Expression Alters Upon Differentiation of Human B Cells and T Cells

B cells and T cells are key players in the defence against infections and malignancies. To exert their function, B cells and T cells differentiate into effector and memory cells. Tight regulation of these differentiation processes is key to prevent their malfunction, which can result in life-threatening disease. Lymphocyte differentiation relies on the appropriate timing and dosage of regulatory molecules, and post-transcriptional gene regulation (PTR) is a key player herein. PTR includes the regulation through RNA-binding proteins (RBPs), which control the fate of RNA and its translation into proteins. To date, a comprehensive overview of the RBP expression throughout lymphocyte differentiation is lacking. Using transcriptome and proteome analyses, we here catalogued the RBP expression for human B cells and T cells. We observed that even though the overall RBP expression is conserved, the relative RBP expression is distinct between B cells and T cells. Differentiation into effector and memory cells alters the RBP expression, resulting into preferential expression of different classes of RBPs. For instance, whereas naive T cells express high levels of translation-regulating RBPs, effector T cells preferentially express RBPs that modulate mRNA stability. Lastly, we found that cytotoxic CD8+ and CD4+ T cells express a common RBP repertoire. Combined, our study reveals a cell type-specific and differentiation-dependent RBP expression landscape in human lymphocytes, which will help unravel the role of RBPs in lymphocyte function.

Electrical Screening Method of VNAND Flash Channel Hole Bending Defects

A novel electrical screening method of channel hole bending (ChB) defects is proposed for the implementation of high-density vertical NAND (VNAND) flash memory. The ChB defects induces the leakage current between the two adjacent channel holes, which leads to fatal failure in storage systems. Thus, it is one of the key requirements for VNAND mass production to screen ChB defects electrically in advance. In the proposed screening method, a 3D checkerboard (CKBD) pattern is introduced, which consists of alternating programed (‘0’) and inhibited (‘1’) memory cells in a diagonal and horizontal direction. By measuring the leakage current between the channel holes, ChB defects can be successfully detected electrically.