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Objectives: Total number of avoided endoscopies using Baveno VI criteria is relatively low. Spleen elastography is an attractive tool and when compared with liver stiffness, it better represents the dynamic changes occurring in portal hypertension. The aim of the study was to evaluate spleen shear wave elastography (SWE) in compensated advanced chronic liver disease (cACLD) patients for ruling out the presence of esophageal high-risk varices (HRV). Methods: A total of 401 patients with cACLD were included in this cross-sectional study. The total sample was split into training set (200 patients) and validation set (201 patients). Spleen stiffness was measured with two-dimensional shear wave elastography (2D SWE). Esophageal HRV were defined as large varices (diameter >5 mm) or small varices with red color signs. In the training set, the receiver operating characteristic (ROC) curve was drawn and the area under the curve (AUC) of spleen SWE was assessed. A cutoff value was chosen (highest sensitivity and negative predictive value). In the validation set, the spleen SWE cutoff score and Baveno VI criteria were validated. Results: The prevalence of HRV was 12% in the training set and 13% in the validation set. Spleen SWE had an AUC of 0.89 in ruling out the presence of high-risk esophageal varices (cutoff value of 48.7 kPa, sensitivity of 100%, and specificity of 53%). Validating spleen SWE ≤48.7 kPa in a different cohort of 201 cACLD patients, 55% of screening endoscopies could be avoided without missing any HRV, whereas using Baveno VI criteria only 30% of screening endoscopies could be spared. Conclusion: Spleen SWE ≤48.7 kPa was able to identify cACLD patients who could safely avoid screening endoscopy with good accuracy. Spleen SWE could avoid an additional 25% of screening endoscopies compared to the Baveno VI criteria and no HRV were missed.

Introduction: Barrett’s esophagus (BE) is a complication of gastroesophageal reflux disease (GERD). It is seen among 15% of GERD patients as per a population-based study by Ronkainen et al. Barrett’s has malignant potential and annual progression to carcinoma depends on the presence or absence of dysplasia. There are various risk factors for the development of BE. We compared two symptomatic cohorts of GERD patients from the same geographical area who were evaluated for the presence of Barrett’s and various factors that can contribute to Barrett’s. Materials and methods: Cross-sectional study. Two GERD cohorts, one from Kottayam and the other from Trivandrum were taken. The presence of Barrett’s and the factors contributing to the development of Barrett’s were analyzed between the two groups. Since biopsy data of all patients were not available, endoscopically suspected esophageal metaplasia (ESEM) was taken as Barrett’s. Results: 415 patients were enrolled for the study (203 from Trivandrum and 212 from Kottayam). 192 females (99 from Trivandrum and 93 from Kottayam), and 223 males (104 from Trivandrum and 119 from Kottayam). Barrett’s esophagus and especially long-segment Barrett’s were significantly more common in Kottayam than Trivandrum (68 vs 22 and 36 vs 9) (p-value 50 years) was not statistically significant among the two cohorts (mean age of Trivandrum was 48 years and Kottayam was 49 years). Duration of GERD symptoms was significantly more in the Trivandrum cohort compared to Kottayam (p-value

Hardware acceleration of deep learning using analog non-volatile memory (NVM) requires large arrays with high device yield, high accuracy Multiply-ACcumulate (MAC) operations, and routing frameworks for implementing arbitrary deep neural network (DNN) topologies. In this article, we present a 14-nm test-chip for Analog AI inference--it contains multiple arrays of phase change memory (PCM)-devices, each array capable of storing 512 x 512 unique DNN weights and executing massively parallel MAC operations at the location of the data. DNN excitations are transported across the chip using a duration representation on a parallel and reconfigurable 2-D mesh. To accurately transfer inference models to the chip, we describe a closed-loop tuning (CLT) algorithm that programs the four PCM conductances in each weight, achieving

We demonstrate a novel process for building a Resistive RAM (ReRAM) stack which reduces the forming voltage ( $\text{V}_{\textit {form}}$ ) and increases the switching resistance, both characteristics that are important ingredients for the use of ReRAM in scalable analog compute for AI. Utilizing this process, we explore analog switching characteristics above 100k $\Omega $ and demonstrate 4-bit programming at Rmax $=1\text{M}\Omega $ . Utilizing the same writing characteristics, CIFAR-10 inference simulation shows 90% accuracy, comparable to the full precision model accuracy.

Recent advances in deep neural network demand more than millions of parameters to handle and mandate the high-performance computing resources with improved efficiency. The cross-bar array architecture has been considered as one of the promising deep learning architectures that shows a significant computing gain over the conventional processors. To investigate the feasibility of the architecture, we examine non-idealities and their impact on the performance. Specifically, we study the impact of failed cells due to the initialization process of the resistive memory based cross-bar array. Unlike the conventional memory array, individual memory elements cannot be rerouted and, thus, may have a critical impact on model accuracy. We categorize the possible failures and propose hardware implementation that minimizes catastrophic failures. Such hardware optimization bounds the possible logical value of the failed cells and gives us opportunities to compensate for the loss of accuracy via off-line training. By introducing the random weight defects during the training, we show that the model becomes more resilient on the device initialization failures, therefore, less prone to degrade the inference performance due to the failed devices. Our study sheds light on the hardware and software co-optimization procedure to cope with potentially catastrophic failures in the cross-bar array., 17 pages, 7 figures

We demonstrate a MIM capacitor structure using ZrO2 for the dielectric layer which exhibits a 25% capacitance increase (from ~43fF/mm2 to >55fF/mm2 for a ~55A film) with minimal leakage current increase compared to Hf based dielectrics, extending the usefulness of MIM on-chip decoupling capacitors. The MIM structure, suitable for BEOL processing is TiN/ZrO2/TiN combined with an anneal which is shown to improve the capacitance vs. leakage performance compared to doped and undoped HfO2 based control structures. GI-XRD measurements demonstrate that the capacitance increase corresponds with a phase transformation of the ZrO2 from amorphous to cubic phase, which is shown to have a dielectric constant (k) up to 35. Reliability models based on hard-breakdown (HBD) show that this structure exceeds the end-of-life targets. Servers and high-performance chips have historically relied on on-chip decoupling capacitors (decap) to reduce power supply noise in order to achieve 3 – 5.4 GHz operating frequency. Although packaging decap can be very effective at mitigating low and mid-frequency noise, on-chip decap, such as MIMCAP, is critical for mitigating mid and high-frequency noise. As Fig. 1 shows, an increase in on-chip decap can result in a significant performance benefit, due to their fast response time slowing the fastest droops, giving time for slower response elements to contribute. One method of achieving this increased decap is to increase the k of the material being used as the insulator in the MIMCAP. Following high-k gate dielectric technology, HfO2 and other Hf based dielectric stacks have been used for this layer successfully [1]. But there is a significant difference in the thermal budget that the dielectric is exposed to following the deposition between gate dielectric and MIMCAP applications. The gate dielectric, deposited prior to any metallization, will typically be exposed to a relatively high thermal budget compared to the insulator layer of a decoupling MIMCAP, which is usually placed between wiring levels in the back end of the line (BEOL) [2]. Since the thermal budget after deposition will affect the crystal structure of a material, and different crystal phases of the same material can have dramatically different dielectric constants [3], the actual dielectric constant of a particular high-k material may vary significantly depending on whether it is used as the gate dielectric or as the MIM insulator. In this work, we explore the use of a ZrO2 as the high- k layer for MIMCAP applications and show that its low crystallization temperature enables it to achieve a significantly higher k value compared to HfO2 when processed under BEOL compatible thermal conditions. Fig. 2 shows the development of the high-k phase of a 55A ZrO2 film as the anneal temperature is increased. The peaks at 35, 42 and 52 are the signature of the bottom TiN electrode and do not change with anneals; but the peaks at 30.2 and 50.3 degrees, which are seen to develop as the anneal temperature increases, match with the 111 and 220 planes of the cubic phase of ZrO2. MIMCAPs built using similarly annealed ZrO2 layers as dielectrics exhibit an increase in capacitance as shown in Fig. 3a: there is a slight increase after anneal A, significantly more increase after anneal B, and additional moderate increases after C and D. No such capacitance increase is seen when Hf based dielectrics are used (Fig. 3b). The maximum capacitance is found to be ~56fF/um2 after anneal D compared to ~43fF/um2 for the unannealed device, an increase of more than 25%, while the leakage current remains virtually unchanged at 1V, and increases by 2. Thus, we can achieve high capacitance with a relatively thick high-k layer, keeping the leakage current low, all while maintaining compatibility with BEOL processing. [1] T. Ando et al., “CMOS Compatible MIM Decoupling Capacitor with Reliable Sub-nm EOT High-k Stacks for the 7nm Node and Beyond,” Tech. Dig. IEDM 2016, pp. 9.4.1 - 9.4.4. [2] K. Fischer et al., “Low-k Interconnect Stack with multi-layer Air Gap and Tri-Metal-Insulator-Metal Capacitors for 14-nm High Volume Manufacturing,” IEEE Interconnect Tech. Conf. 2015, 10.1109/IITC-MAM.2015.7325600. [3] X. Zhao and D. Vanderbilt, “First-principles Study of Electronic and Dielectric Properties of ZrO2 and HfO2” MRS Proceedings, 747. doi:10.1557/PROC-747-T5.2/N7.2. Figure 1

Introduction: The effectiveness of a local anaestheticis increased by the addition of an adjuvant. Magnesium sulphate along with bupivacaine is effective in reducing the pain and extending the analgesia period. Aim: To compare the duration of analgesia among subjects receiving plain bupivacaine and bupivacaine with magnesium sulphate among patients undergoing total abdominal hysterectomy. Materials and Methods: This double-blinded randomised clinical trial was conducted in Department of Anaesthesiology at Shri Sathya Sai Medical College and Research Institute, Ammapettai, Tamil Nadu, India, (tertiary care center) between November 2019 and October 2021. The study was done among 50 subjects undergoing elective total abdominal hysterectomy. The subjects were divided into two groups, one group received only bupivacaine while the other group received bupivacaine with 500 mg magnesium sulphate. Onset and duration of blocks were observed. Haemodynamic parameters were monitored intraoperatively and postoperatively. Data was analysed using Chi-square test, Fischer’s exact test. Results: Demographic variables like age (p-value=0.17), height (p-value=0.62), weight (p-value=0.14) and BMI (p-value=0.24) were comparable between the two groups. The mean duration of analgesia was significantly more among the bupivacaine and magnesium sulphate group (416.72±93.6) in comparison to the bupivacaine alone group (204.56±71.25). The bupivacaine and magnesium sulphate group required two doses of rescue analgesia in 24 hours, while the other group required four doses of analgesia. Significantly more side-effects were noted among the bupivacaine alone group (12 vs 6) (p-value=0.04). Conclusion: The study showed that bupivacaine and magnesium sulphate group showed less intraoperative side effects, reduced postoperative VAS score increased duration of analgesia, decreased requirement of analgesia required in 24 hours and reduced postoperative side-effects.

Introduction: Nonalcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver disease. The spectrum of NAFLD includes simple steatosis, nonalcoholic steatohepatitis (NASH), advanced fibrosis, and cirrhosis. Our study aimed to calculate visceral fat volume at the L3–L4 vertebral level and its association with hepatic fibrosis assessed by transient elastography. Methods: All patients above 18 years undergoing computed tomography (CT) abdomen in the Department of Radiodiagnosis of Medical College Thiruvananthapuram during the study period with NAFLD were included. Transient elastography was done. Patients were categorized to advanced fibrosis (>10 kPa) and without advanced fibrosis (10 kPa) and 34 (54%) patients were without advanced fibrosis. About 0.733 was the AUROC for visceral fat in predicting advanced fibrosis. The cutoff was 167.5cm3 (sensitivity was 77.4% and specificity was 51.5% in predicting advanced fibrosis). Conclusion: About 0.733 was the AUROC for visceral fat in predicting advanced fibrosis. The cutoff was 167.5cm3 (sensitivity was 77.4% and specificity was 51.5% in predicting advanced fibrosis).