Existing nonvolatile ternary content-addressable-memory (nvTCAM) suffers from limited word-length (WDL), large write-energy (E W ) and search-energy (E S ), and large cell area (A). This paper ...develops a 3T1R nvTCAM cell using a single multiple-level cell (MLC)-resistive RAM (ReRAM) device to achieve long WDL, lower E W and E S , and reduced cell area. Two peripheral control schemes were developed, dual-replica-row selftimed and invalid-entry power consumption suppression (IEPCS), for the suppression of dc current in 3T1R nvTCAM cells in order to reduce E S . Two versions of the IEPCS scheme were developed (basic and charge-recycle-controlled) to alter the tradeoff between area overhead and power consumption in the updating of invalid-bits. A 128 b × 64 b 3T1R nvTCAM macro was fabricated using back-end-of-line ReRAM under 90-nm CMOS process. The fabricated MLC-based 3T1R nvTCAM macro achieved sub-1-ns search-delay and sub-6-ns wake-up time with supply voltage of 1 V and WDL = 64 b.
Tyrosine kinase inhibitors (TKIs) that target BCR-ABL are the frontline treatments in chronic myeloid leukemia (CML). Growing evidence has shown that TKIs also enhance immunity. Since gamma-delta T ...(γδT) cells possess the potent anticancer capability, here we investigated the potential involvement of γδT cells in TKI treatments for CML. We characterized γδT cells isolated from chronic-phase CML patients before and during TKI treatments. γδT expression increased significantly in CML patients who achieved major molecular response (MMR) and deep molecular response (DMR). Their Vδ2 subset of γδT also expanded, and increased expression of activating molecules, namely IFN-γ, perforin, and CD107a, as well as γδT cytotoxicity. Mechanistically, TKIs augmented the efflux of isopentenyl pyrophosphate (IPP) from CML cells, which stimulated IFN-γ production and γδT expansion. Notably, the size of the IFN-γ
naïve γδT population in TKI-treated CML patients was strongly correlated with their rates to reach DMR and with the duration on DMR. Statistical analysis suggests that a cutoff of 7.5% IFN-γ
naïve subpopulation of γδT in CML patients could serve as a determinant for MR
sustainability. Our results highlight γδT cells as a positive regulator for TKI responses in CML patients.
Many cost-aware IoE devices require embedded nonvolatile memory (eNVM) to achieve high-speed read and low-power write operations for serving as code and data storage unit. Resistive random access ...memory (ReRAM) is a good candidate for eNVM of Internet-of-Everything (IoE) but suffers low read yield and require long read latency (<inline-formula> <tex-math notation="LaTeX">T_{\text {CD}} </tex-math></inline-formula>) against small <inline-formula> <tex-math notation="LaTeX">R </tex-math></inline-formula>-ratio, large cell-resistance variations, and device-mismatch induced input offset at current-mode sense amplifier (CSA). The wide distribution in write time also causes large wasted write power (<inline-formula> <tex-math notation="LaTeX">E_{\text {W}} </tex-math></inline-formula>) and long NVM-stress-time (<inline-formula> <tex-math notation="LaTeX">T_{\text {STRS}} </tex-math></inline-formula>). This paper proposes a bitline-current-aware small-offset CSA, using dynamic trip-point-mismatch sampling (DTPMS) scheme, to improve read yield and shorten <inline-formula> <tex-math notation="LaTeX">T_{\text {CD}} </tex-math></inline-formula>. This paper also proposes a low dc-current voltage-mode write termination (LDC-VWT) module, including SET and RESET termination circuits, to suppress <inline-formula> <tex-math notation="LaTeX">E_{\text {W}} </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">T_{\text {STRS}} </tex-math></inline-formula>. A fabricated 65-nm 2-Mb ReRAM macro achieved <inline-formula> <tex-math notation="LaTeX">T_{\text {CD}}= 2.6 </tex-math></inline-formula> ns and confirm the write-termination operations for reduction in <inline-formula> <tex-math notation="LaTeX">T_{\text {STRS}} </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">E_{\text {W}} </tex-math></inline-formula>.
This paper outlines the RC-filtered stress-decoupled (RCSD) 4T2R nonvolatile TCAM (nvTCAM) with the following benefits: 1) reduced NVM-stress; 2) reduced ML parasitic load; and 3) suppression of ...match-line (ML) leakage current from match cells. The RCSD-4T2R cell achieves a 6× reduction in NVM-stress, a 2× increase in maximum wordlength, and a 2× reduction in search delay. In this paper, we also outline two search schemes, referred to as dynamic source-line pulse controlled (DSL-PC) search and dataline-pulse controlled (DL-PC) search, which were developed specifically for the RCSD-4T2R nvTCAM. We fabricated a 128 × 32 b RCSD-4T2R nvTCAM macro with HfO ReRAM using a 180 nm CMOS process. Using the DSL-PC and DL-PC schemes, the measured search delay of the RCSD-4T2R nvTCAM macro was 1.2 ns under typical VDD.
Many IoT and wearable devices require an on-chip small-to-mid-capacity nonvolatile memory (NVM) with a fast read-access time (T AC ) and reliable read operations: for applications including ...data-logging, configurable look-up tables (LUT), eFuse, and physically unclonable functions (PUF). STT-MRAM 1-4 is a good candidate for these applications due to its fast write speed, low-voltage write, and high endurance. However, STT-MRAM suffers from a small read-signal margin (RSM) due to a small tunnel magnetoresistance ratio (TMR: (R AP -R P )/R P ) between the cell resistance of parallel (P, R P ) and anti-parallel (AP, R AP ) states 1-6. Moreover, the read-disturb behavior of STT-MRAM cells is sensitive to the BL read voltage (V BL_RD ) and the stress/read time. Compact 1T1MTJ arrays are suitable for high-density applications 5-6; however, they use a power-hungry current-mode read scheme with a slow read speed due to the small RSM. Researchers have proposed 2T2MTJ (Fig. 30.3.1) arrays 1-4 with differential bitlines (BL and BLB) and a voltage-mode read scheme, with an enlarged RSM (V RSM ), for fast, low-power read operations. V RSM refers to the voltage difference between BL (V BL )and BLB (V BLB ). 2T2MTJ STT-MRAM read operations still face the following challenges: (1) V BL and V BLB both drop from V BL_RD to 0V quite quickly due to the large cell read current (V P and V AP ) or low R-value in both R P and R AP , resulting in small sensing window (T SMW ), which is the period when V RSM >offset; (2) the maximum V RSM (V RSM_MAX ) occurs at different times (t RSM_MAX ) for different cells due to TMR (R AP /R P ) variation; and (3) a degraded V RSM due to the use of a low V BL_RD to avoid read disturbs for high data-reliability applications. (1) and (2) lead to a decrease in V RSM after reaching its peak (t RSM_MAX ), despite an increase in BL development time (t BL ). When using a conventional voltage-mode sense amplifier (CNV-VSA) with a common activated (SAEN=1) timing (f SAEN ) under the effects of (1)-(3), the signal to be amplified (ΔV IN <;V RSM_MAX ) is subject to degradation at the VSA's differential inputs, resulting in a sensing failure at a low V BL_RD .
Group A streptococcus (GAS) is a versatile pathogen that causes a wide spectrum of diseases in humans. Invading host cells is a known strategy for GAS to avoid antibiotic killing and immune ...recognition. However, the underlying mechanisms of GAS resistance to intracellular killing need to be explored. Endothelial HMEC-1 cells were infected with GAS, methicillin-resistant
(MRSA) and
Typhimurium under nicotinamide (NAM)-supplemented conditions. The intracellular NAD
level and cell viability were respectively measured by NAD
quantification kit and protease-based cytotoxicity assay. Moreover, the intracellular bacteria were analyzed by colony-forming assay, transmission electron microscopy, and confocal microscopy. We found that supplementation with exogenous nicotinamide during infection significantly inhibited the growth of intracellular GAS in endothelial cells. Moreover, the NAD
content and NAD
/NADH ratio of GAS-infected endothelial cells were dramatically increased, whereas the cell cytotoxicity was decreased by exogenous nicotinamide treatment. After knockdown of the autophagy-related ATG9A, the intracellular bacterial load was increased in nicotinamide-treated endothelial cells. The results of Western blot and transmission electron microscopy also revealed that cells treated with nicotinamide can increase autophagy-associated LC3 conversion and double-membrane formation during GAS infection. Confocal microscopy images further showed that more GAS-containing vacuoles were colocalized with lysosome under nicotinamide-supplemented conditions than without nicotinamide treatment. In contrast to GAS, supplementation with exogenous nicotinamide did not effectively inhibit the growth of MRSA or
Typhimurium in endothelial cells. These results indicate that intracellular NAD
homeostasis is crucial for controlling intracellular GAS infection in endothelial cells. In addition, nicotinamide may be a potential new therapeutic agent to overcome persistent infections of GAS.
Regular expression matching becomes indispensable elements of Internet of Things network security. However, traditional ternary content addressable memory (TCAM) search engine is unable to handle ...patterns with wildcards, as it precisely tracks only one active state with single transition. This paper proposes a promising simultaneous pattern matching methodology for wildcard patterns by two separated engines to represent discrete finite automata. A key preprocessing to encode possible postfix pattern by a unique key ensures that follow-up patterns can accurately traverse all possible matches with limited hardware resources. This approach is practical and scalable for achieving good performance and low space consumption in network security, and it can be applicable to any regular expressions even with multiwildcard patterns. The experimental results demonstrate that this scheme can efficiently and accurately recognize wildcard patterns by simultaneously tracking only two active states. By adopting SRAM TCAM in the proposed architecture, the energy consumption is reduced to around 39%, compared with the energy consumption using a computing system that contains a large memory lookup and comparison overhead.
Many search engines or filters for the internet-of-things and big-data employ ternary content-addressable-memory (TCAM) to suppress power consumption in the transmission of data between end-devices ...and servers. Nonvolatile TCAMs (nvTCAM) are designed to achieve zero standby power with smaller area overhead and faster power off/on operations than those found in conventional TCAM+NVM 2-macro schemes. In this paper, we discuss the challenges involved in the design of nvTCAMs and propose a universal 5T2R nvTCAM cell with tolerance for the various R-ratios and write parameters associated with emerging memory devices. A 128×64b-nvTCAM macro was fabricated using HfO ReRAM and a 90nm-CMOS process for concept verification.
Recent embedded ReRAM has a small resistance-ratio (R-ratio), which results in a small read sensing margin (I SM ). A larger BL current (I BL ) increases the input offset (I OS ) of current-mode ...sense amplifiers (CSA), resulting in low-yield read operations and long read access times (T CD ). This work proposes an I BL -aware small-I OS CSA, using a dynamic trip-point-mismatch sampling (DTPMS) scheme to increase tolerance for small I SM and residual BL precharge current (I PRE ) in order to improve memory yield and speed up T CD in cases of small R-ratio. A fabricated 65nm 2Mb ReRAM macro achieved T CD =2.6ns at VDD=1V. For the first-time, a ReRAM macro with sub-3ns T CD is presented.
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