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PE_PGRS33 is a member of multi-gene family restricted to pathogenic Mycobacteria and their functions remain elusive. PE_PGRS33 is highly polymorphic in nature to evade host's immune response. Therefore, we investigated PE_PGRS33 gene polymorphisms in clinical isolates and functional characterization using in vitro experiments. A total of 103 clinical isolates were recruited. Genomic DNA was extracted, PE_PGRS33 gene amplification, sequencing. Afterward, we have cloned, expressed PE_PGRS33 wild type and three polymorphic alleles in M. smegmatis. Further, performed in vitro stresses assays, THP-1 differentiated macrophage infection assays followed by quantification of cytokine expression. We have identified nine novel polymorphisms and also demonstrated that in comparison to M. smegmatis expressing wild type/Mut_alleles displayed altered in growth kinetics and colony morphology. M. smegmatis harbouring Mut_allele3 survived better under oxidative, acidic stress and were resistant to lysozyme treatment. qRT-PCR of cytokines TNF-α, IL-12 and IL-10 after infection with recombinant M. smegmatis showed two Mut_allele (Mut_allele1 and Mut_allele3) induced higher expression of TNF-α, IL-12, while IL-10 expression was decreased in both mutant alleles as compared to wild type PE_PGRS33 at each experimental time point. Results of our functional study suggest that PE_PGRS33 gene polymorphisms aid in the survival or persistence of M. tuberculosis and differentially modulate the expression of various cytokines. Overall this study suggests that Mtb clinical strains harbouring different PE_PGRS33 alleles could act as a virulence determinant by differentially regulating pathways essential for the pathogen's ability to adapt inside the host. [ABSTRACT FROM AUTHOR]

Gallbladder cancer is one of the most common cancers of biliary tract with aggressive pathophysiology, now emerging as a global health issue. Although minority of gallbladder cancer patients could receive such curative resection due to late diagnosis, this increases the survival rate. Lack of potential target molecule (s) for early diagnosis, better prognosis and effective therapy of gallbladder cancer has triggered investigators to look for novel technological or high throughput approaches to identify potential biomarker for gallbladder cancer. Intervention of non-coding RNAs in gallbladder cancer has been revealed recently. Non-coding RNAs are now widely implicated in cancer. Recent reports have revealed association of non-coding RNAs (microRNAs or miRNAs and long non-coding RNAs or lncRNAs) with gallbladder cancer. Here, we present an updated overview on the biogenesis, mechanism of action, role of non-coding RNAs, the identified cellular functions in gallbladder tumorigenesis, their prognostic & therapeutic potentials (efficacies) and future significance in developing effective biomarker(s), in future, for gallbladder. [ABSTRACT FROM AUTHOR]

Highlights: [•] A short channel threshold voltage model is presented for Re-S/D SOI MOSFETs. [•] The effect of substrate induced surface potential is considered in modeling. [•] The effect of substrate bias voltage is demonstrated on threshold voltage. [•] At shorter channel length, back surface of silicon body gets inverted earlier. [•] The front/back channel dominance is studied with device parameters. [Copyright &y& Elsevier]

A comprehensive subthreshold model of asymmetric gate all around (GAA) junctionless (JL) FETs with scaled equivalent oxide thickness is developed in the work. The perimeter weighted sum approach is implemented to model the channel potential and threshold voltage of the device. Further, a novelty in the perimeter weighted approach is proposed to model subthreshold slope of the device. With the proposed novelty appended, the perimeter weighted approach can present a complete subthreshold solution of three dimensional multi-gate devices. Silicon dioxide, Silicon nitride, and stack of Hafnium oxide with interfacial Silicon dioxide are implied as gate dielectric to study the scaling of equivalent oxide thickness of the device in sub-1nm domain. The device characteristics for asymmetric GAA structure imparted due to the dielectric thickness asymmetry have been studied. The numerical results are compared with 3D Sentaurus TCAD device simulation outputs for variation in device parameters. • This work presents subthreshold model of asymmetric gate all around (GAA) junctionless (JL) FETs with scaled equivalent oxide thickness (EOT). • The existing perimeter weighted sum approach can be applied to modelchannel potential and threshold voltage, but not subthreshold slope, of the multi-gate devices. • In the work, a novel perimeter weighted based subthreshold slope model of multi gate three dimensional devices is derived for the first time. • Since scaling of EOT in sub-1nm domain has been adopted in industry for more than a decade, the model assumes the GAA JLFETs with scaled EOT. • The scaling of EOT is achieved by implementing single layer of silicon nitride and stack of high- k dielectric with interfacial SiO 2 layer. [ABSTRACT FROM AUTHOR]

Self-heating in nanoscale gate-all-around (GAA) MOSFETs can be attributed to the low thermal conductivity of channel material, gate dielectric material, and large thermal resistance of the source and drain contacts. Self-heating can severely increase the thermal noise level in nanoscale gate-all-around (GAA) MOSFETs as the peak lattice temperature increases several degrees above the ambient temperature. This work presents a detailed analysis of thermal noise in InGaAs based nanowire (NW)/nanosheet (NS) GAA metal-oxide-semiconductor field-effect transistors (MOSFETs). Calibrated electro-thermal simulation results are used to analyze the influence of interfacial thermal resistance (ITR), the number of nanowires/nanosheets (N) and mole fraction of Gallium on drain noise power spectral density (S ID), induced gate noise power spectral density (S IG), and cross-correlation noise power spectral density (S IC). The impact of engineered source/drain contacts and thermal conductivity of buried oxide (BOX) materials on S ID , S IG , and S IC parameters is also investigated in this work. It is observed that Si 3 N 4 outperforms SiO 2 as a BOX material. The noise power spectral densities such as S ID , S IG , and S IC decrease by 8%, 27%, and 22%, respectively, in NW GAA MOSFETs and 16%, 26%, and 18%, respectively, in NS GAA MOSFETs, when Si 3 N 4 replaces SiO 2 as a BOX layer. [ABSTRACT FROM AUTHOR]

Nanowire Field Effect Transistors (NWFETs) have been considered as the next-generation technology for sub-10 nm technology nodes, succeeding FinFETs. However, the highly confined nature of Nanowire FETs creates reliability issues that significantly impact their performance. Therefore, this work proposes a machine learning-based technique for analyzing the self-heating-induced reliability issues in NWFETs. The influence of self-heating effects in NWFET has been predicted in terms of saturation current (I dsat), threshold voltage (V th), the maximum carrier temperature along the channel (eTmax), and the maximum Lattice temperature (LTmax) with multivariable regression. TCAD-assisted machine learning has been used for algorithm training and prediction. A dataset has been created by varying the parameters of the NWFETs like the thickness of the channel (t si), the thickness of oxide (t ox), Length of source/drain (L sd), length of source/drain contact (L sdc), doping concentrations etc. The Random Forest Regression algorithm has been used to estimate the performance of NWFETs in predicting the desired output parameters suitably with the given dataset. • A machine learning-based technique have been proposed for analysing the self-heating-induced reliability issues in NWFETs. • RFR algorithm is used to estimate the performance of NWFETs in predicting the output parameters with the given dataset. • The influence of self-heating effects in NWFET has been predicted in terms of I dsat , V th , Lattice, and carrier temperature. [ABSTRACT FROM AUTHOR]

Abstract: A model for the subthreshold current and subthreshold swing of fully depleted short-channel Si–SOI-MESFETs is presented in the paper. The subthreshold current of the device is modeled empirically by an exponential function of gate–source and drain–source voltages. The short-channel effects have been included in terms of some empirical constants in the model which have been finally derived from the two-dimensional potential distribution function of the device. The subthreshold swing characteristics of the device are obtained using the subthreshold current model. The validity of the proposed model is shown by comparing the theoretical data with the simulation results obtained by using the ATLAS™ device simulation software. [Copyright &y& Elsevier]

The performance of a silicon nanotube-based feedback field-effect transistor (SiNT FBFET) with a core-source architecture has been explored in this work for the use in logic-in-memory (LIM) applications. Both n-channel and p-channel FETs with extremely symmetric transfer characteristics and a high O N / O F F current ratio of 10 9 are implemented in a single structure using the core and outer gates. SiNT FBFET exhibits significant data retention attributes during memory operations for up to 10 3 s. The SiNT FBFET-based inverter circuit retains output logic states of "1" and "0" for 1.705 s and 1.948 s, respectively, at megahertz operating frequency without standby power consumption. Additionally, SiNT FBFET has also been used to build ternary NAND/NOR logic gates with memory functionality. Numerical mixed-mode simulations of the circuits have been carried out using the commercially available Synopsys "Sentaurus" TCAD tool for examining the performance and memory characteristics of SiNT FBFETs. This study demonstrates the possible use of SiNT FBFET in multivalued logic systems and the development of next-generation memory devices. • A reconfigurable silicon nanotube-based FBFET with a high O N / O F F current ratio of 10 9 and symmetrical current–voltage characteristics for both n and p-channel modes of operation is demonstrated. • A high retention time of 10 3 s in O N / O F F states for both n- and p-channel modes of operation has been observed. • The device achieves superior retention times for output logic states (1.705 s for '1' and 1.948 s for '0') without standby power consumption, aiding in designing logic-in-memory (LIM) features for an inverter. • Universal ternary NAND (TNAND) and ternary NOR (TNOR) logic gates with memory operations have been successfully implemented using SiNT FBFETs. [ABSTRACT FROM AUTHOR]

This paper proposes the structure of a vertical PNPN single gated feedback field-effect transistor (vertical FBFET) and investigates its performance using a TCAD simulator. The performance of the device is investigated against variations in a few geometrical and process parameters. The device exhibits an ultra-steep switching characteristic with a minimum subthreshold swing of 0.03 mV/dec and a high O N / O F F current ratio of ∼ 1011. Subsequently, the hysteresis characteristic of the vertical FBFET is analyzed against variation in interface trap charges at Si and Al 2 O 3 interfaces. Due to the presence of negative/positive interface trap charges at silicon and Al 2 O 3 interface, the memory window is enlarged/reduced from 1.1 V to 1.21 V/0.96 V respectively. The vertical FBFET also shows a wide variation in the memory window for channel length and temperature variations. • Vertical FBFET shows minimum subthreshold swing of 0.03 mV/dec and a high O N / O F F current ratio of ∼ 1011. • Large variation in hysteresis characteristics observed for vertical FBFET for channel length above 70 nm. • Interface trap charges present at interface of silicon and Al 2 O 3 shows variation in memory window up to 0.25 V. [ABSTRACT FROM AUTHOR]

Background As on today, the global mortality rate of gallbladder cancer is still very high. Both genetic and epigenetic alterations play pivotal roles in the development of cancer. We selected seven tumour associated genes, implicated in other cancers, to assess their methylation status in gallbladder cancer and gallstone diseases. Aim of study To study the promoter methylation of certain tumour associated genes in the molecular pathogenesis of gallbladder cancer and gall stone diseases. Materials and methods Methylation specific PCR for seven tumour associated genes, viz., MASPIN, 14-3-3 sigma gene, THBS1, FLNC, HLTF, COX-2 and SOCS1, was performed in 50 gallbladder cancer (GBC), 30 gall stone diseases (GSD) and their respective adjacent control tissues. Semi-quantitative PCR and immunohistochemistry was carried out to check the expression level. Student's t-test was carried out to compare the differences in the methylation and expression patterns between cases and control tissues. Results We observed methylation of CpG islands in seven of the studied markers, but, the frequency of methylation was found varying among different samples. Of them, 14–33 sigma showed methylation in 45 GBC (90%; p = 0.0001) and 25 GSD (86.66%; p = 0.001), MASPIN in 35 GBC (70%; p = 0.0008) and 18 GSD (51.43%; p = 0.040), FLNC in 16 GBC (32%; p = 0.0044) and 9 GSD (25.71%; p = ns), THBS1 in 26 GBC (52%; p = 0.0009) and 10 GSD (28.57%; p = 0.0505), HLTF in 8 GBC (16%; p = ns) and 2 GSD (5.71%; p = ns), COX2 in 10 GBC (20%; p = ns) and 6 GSD (17.14%; p = ns) and SOCS-1 in 3 GBC samples only (6%; p = ns), but not in GSD. Semi-quantitative PCR revealed down regulation in MASPIN, 14-3-3 sigma, THBS1, HLTF, COX2 and SOCS1 in advanced gallbladder cases. Immunohistochemistry further confirmed the down-regulation of SOCS1 in GBC. Conclusion The present study infers that accumulation of epigenetic alterations increases poor prognosis of GBC patients. Out of seven genes, MASPIN and THBS1 play key epigenetic role in GBC, but not in GSD. The reason for downregulation of SOCS1 only in GBC, and unaltered expression of 14-3-3 sigma protein in all the GBC and GSD tissue samples is not clear. Further investigation on the expression pattern of these genes in GBC cell lines may elucidate their likely functional role in in association with gallbladder cancer. [ABSTRACT FROM AUTHOR]

Highlights: [•] HLA class I and II alleles were genotyped at low resolution level in Sahariya tribe. [•] Significant association of HLA-DRB1∗15 with susceptibility to TB was found. [•] We also found significant association of HLA-DRB1∗16 with resistance to TB. [Copyright &y& Elsevier]