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Unconventional functions, including activation functions and power functions, are extremely hard-to-realize primarily due to the difficulty in arriving at the hierarchical design. The hierarchical design allows the synthesis tool to map the functionality with that of standard cells employed through the regular ASIC synthesis flow. For conventional functions, the hierarchical design is structured and then supplied to the synthesis flow, whereas, for unconventional functions, the same method is not reliable, since the current synthesis method does not offer any design-space exploration scheme to arrive at an easy-to-realize design entity. The unconventional functions either take a long synthesis run-time or additional efforts are spent in restructuring the hierarchical design for the desired function to synthesizable ones. Cartesian genetic programing (CGP) allows to not only incorporate custom logic gates for synthesizing the hierarchical design but also aids in the design-space exploration for the targeted function through the custom gates. The CGP configuration evolves difficult-to-realize complex functions with multiple solutions, and filtering through desired Pareto-optimal requirements offers a unique hierarchical design. Incorporating CGP-derived hierarchical designs into the traditional synthesis flow is instrumental for implementing and evaluating higher-order designs comprising nonlinear functional constructs. Six activation functions and power functions that fall in the category of unconventional functions are realized by the CGP method using custom cells to demonstrate the capability. Further, the hierarchical design of these unconventional functions is flattened and compared with the same function that is directly synthesized using basic gates. The CGP-derived synthesis method reports 3× less synthesis time for realizing the complex functions at the hierarchical level compared to the synthesis using basic gate cells. Hardware characteristics and error metrics are also investigated for the CGP realized complex functions and are made freely available for further usage to the research and designers’ community.

Abstract A COVID-19 patient often presents with multiple comorbidities and is associated with adverse outcomes. A comprehensive assessment of the prevalence of comorbidities in patients with COVID-19 is essential. This study aimed to assess the prevalence of comorbidities, severity and mortality with regard to geographic region, age, gender and smoking status in patients with COVID-19. A systematic review and multistage meta-analyses were reported using PRISMA guidelines. PubMed/MEDLINE, SCOPUS, Google Scholar and EMBASE were searched from January 2020 to October 2022. Cross-sectional studies, cohort studies, case series studies, and case–control studies on comorbidities reporting among the COVID-19 populations that were published in English were included. The pooled prevalence of various medical conditions in COVID-19 patients was calculated based on regional population size weights. Stratified analyses were performed to understand the variations in the medical conditions based on age, gender, and geographic region. A total of 190 studies comprising 105 million COVID-19 patients were included. Statistical analyses were performed using STATA software, version 16 MP (StataCorp, College Station, TX). Meta-analysis of proportion was performed to obtain pooled values of the prevalence of medical comorbidities: hypertension (39%, 95% CI 36–42, n = 170 studies), obesity (27%, 95% CI 25–30%, n = 169 studies), diabetes (27%, 95% CI 25–30%, n = 175), and asthma (8%, 95% CI 7–9%, n = 112). Moreover, the prevalence of hospitalization was 35% (95% CI 29–41%, n = 61), intensive care admissions 17% (95% CI 14–21, n = 106), and mortality 18% (95% CI 16–21%, n = 145). The prevalence of hypertension was highest in Europe at 44% (95% CI 39–47%, n = 68), obesity and diabetes at 30% (95% CI, 26–34, n = 79) and 27% (95%CI, 24–30, n = 80) in North America, and asthma in Europe at 9% (95% CI 8–11, n = 41). Obesity was high among the ≥ 50 years (30%, n = 112) age group, diabetes among Men (26%, n = 124) and observational studies reported higher mortality than case–control studies (19% vs. 14%). Random effects meta-regression found a significant association between age and diabetes (p

Goal: Conventionally, a surgeon's skill is assessed through visual observation by experts and by tracking patient outcomes. These techniques are very subjective and demands enormous time and effort. Hence, the aim of this study is to construct a framework for automated objective assessment of micro-neurosurgical skill. Methods: A mask region-based convolution neural network (RCNN) is trained to identify and localize instances of surgical instruments from the recorded neurosurgery videos. Then the tool motion and tool handling metrics are computed by tracking the detected instrument locations through time. Microscope adjustment patterns are also investigated via the proposed time based metrics.Results: This study highlights the metrics that could potentially emphasize the variance in expertise between a veteran and a novice. These variations include an expert exhibiting a lower velocity, lower acceleration, lower jerks, reduced path length, higher normalized angular displacement, increased bi-manual handling, shorter idle time and smaller inter tool-tip distances while handling tools accompanied with frequent microscope adjustments and reduced maximum and median intervals between adjustments when compared to a novice. Conclusions: The developed vision based framework has proven to be a reliable method to assess the degree of surgical skill objectively and offer prompt and precise feedback to the neurosurgeons.

Abstract SincNet architecture has shown significant benefits over traditional Convolutional Neural Networks (CNN), especially for speaker recognition applications. SincNet comprises parameterized Sinc functions as filters in the first layer followed by convolutional layers. Although SincNet is compact in nature and offers top-level understanding of the features extracted, the effect of window function used in SincNet is not thoroughly addressed yet. Hamming and Hann are popularly used as the default time-localized windows to reduce spectral leakage. Hence, a comprehensive investigation of 28 different windowing functions on SincNet architecture towards speaker recognition task using TIMIT dataset was performed in this work. Additionally, “trainable” window functions were configured with tunable parameters to characterize the performance. The paper benchmarks the effect of the time-localized windowing function in terms of the bandwidth, side-lobe suppression, and spectral leakage for the filter banks employed in the first layer of the SincNet architecture. Trainable Gaussian and Cosine-Sum functions exhibited relative improvement of 41.46% and 82.11% in the sentence level classification error rate over Hamming window when employed on SincNet architecture.

The problem of immobility of legs leading to a potentially life threatening condition including deep venous thrombosis (DVT) is well known. The reduced mobility of leg affects a large number of patients in a wide range of clinical scenarios spanning from swelling of the legs to pulmonary embolism. In normal human beings, an elegant system of venous return, both active and passive is responsible for prevention of deep venous thrombosis. The paper proposes a prophylaxis and exercise device that mimics the natural principles of venous return to promote the blood flow. The device is based on electromechanical actuation, and simultaneous alternating compression mechanism, that is compact and, suitably form fitted in design and additionally requires no specialised training for the usage. The device was tested on a healthy volunteer on two different days and findings support the efficacy of the prophylaxis and exercise device in significantly improving the blood flow rate in the lower limb. The prototype device is considered as a major step towards designing a clinically validated lower limb device.

Neurosurgical procedures are performed using operating microscopes. The technology of most microscopes has not changed much over the past 60 years. The National Institute of Mental Health and Neurosciences and International Institute of Information Technology based at Bengaluru have embarked on joint collaboration for developing robot for neurosurgical applications. As a working prototype, robotic microscope Mythri 1.0 has been developed. An overview of the development process, working, and features of the device is presented in the article.

Percutaneous coronary intervention (PCI) is increasingly employed in the treatment of complex coronary artery disease. The entrapment or fracture of a coronary angioplasty guidewire is a rare complication of PCI. We herein describe a 61-year-old man who presented with chronic stable angina. The patient’s coronary angiogram revealed triple-vessel coronary artery disease, and he was scheduled for primary PCI. During the procedure, the guidewire fractured within the right coronary artery. Despite multiple attempts, the wire could not be retrieved. The wire unraveled in its coils, and its stretching resulted in its eventual snapping in the right radial artery. The initial plan was to attempt guidewire retrieval through a brachial cut-down, and if successful, to manage the obtuse marginal lesion by PCI, thereby precluding general anesthesia and a sternotomy. Unfortunately, the guidewire snapped at the brachial level, necessitating its retrieval by coronary artery bypass surgery. The patient remained asymptomatic and event-free over 6 months of follow-up.

Stereotactic techniques are used in a wide range of neurosurgical procedures. The procedures demand a high degree of spatial accuracy and minimal error. There are diverse functional surgeries that require stereotactic procedures, including deep brain stimulation, brain biopsies, and epilepsy procedures. Though the disease processes are diverse, all these procedures require accurate targeting of deep structures without visual guidance. The use of robots for stereotactic procedures is a natural progression in the surgeon's quest for higher accuracy and lower complications. This paper reviews the role of robots in stereotactic procedures and outlines current status of robots in stereotactic procedures. The shortcomings of current systems and an outline of an ideal stereotactic device are presented.

The present paper discusses the numerical investigation of turbulent premixed flames under lean conditions. Lean premixed combustion, a low NOx emission technique but are prone to instabilities, extinction and blow out. Such flames are influenced by preferential diffusion due to different mass diffusivities of reactants and difference between heat and mass diffusivities in the reaction zone. In this numerical study, we estimate non-reacting flow characteristics with implementation of an Algebraic Flame Surface Wrinkling Model (AFSW) in the open source CFD code OpenFOAM. In these flows, the mean velocity fields and recirculation zones were captured reasonably well by the RANS standard k-epsilon turbulence model. The simulated turbulent velocity is in good agreement with experiments in the shear-generated turbulence layer. The reacting flow study was done at three equivalence ratios of 0.43, 0.5 and 0.56 to gauge the ability of numerical model to predict combustion quantities. At equivalence ratios 0.5 and 0.56 the simulations showed numerical oscillations and non-convergence of the turbulent quantities. This leads to a detailed parametric variation study where, the pre-constant of AFSW model is varied with values 0.3, 0.35 and 0.4. However the study revealed the weak dependence of pre-constant value on the equivalence ratio. Hence the pre-constant value is fit for specific equivalence ratio based on the parametric variation study. The tuned AFSW model with fitted pre-constant specific to given equivalence ratio predicted are compared with experiments and discussed. The tuned AFSW model produced turbulent flame speed values which are good agreement with experiments.

Rationale. Contact investigation is an established tool for early case detection of tuberculosis (TB). In India, contact investigation is not often conducted, despite national policy, and the yield of contact investigation is not well described. Objective. To determine the yield of evaluating household contacts of sputum smear-positive TB cases in Rajnandgaon district, Chhattisgarh, India. Methods. Among 14 public health care facilities with sputum smear microscopy services, home visits were conducted to identify household contacts of all registered sputum smear-positive TB cases. We used a standardized protocol to screen for clinical symptoms suggestive of active TB with additional referral for chest radiograph and sputa collection. Results. From December 2010 to May 2011, 1,556 household contacts of 312 sputum smear-positive TB cases were identified, of which 148 (9.5%) were symptomatic. Among these, 109 (73.6%) were evaluated by sputum examination resulting in 11 cases (10.1%) of sputum smear-positive TB and 4 cases (3.6%) of smear-negative TB. Household visits contributed additional 63% TB cases compared to passive case detection alone. Conclusion. A standard procedure for conducting household contact investigation identified additional TB cases in the community and offered an opportunity to initiate isoniazid chemoprophylaxis among children.

BackgroundEach follow-up during the course of tuberculosis treatment currently requires two sputum examinations. However, the incremental yield of the second sputum sample during follow-up of different types of tuberculosis patients has never been determined precisely.ObjectivesTo assess the incremental yield of the second sputum sample in the follow-up of tuberculosis patients under the Revised National Tuberculosis Control Programme (RNTCP) in Chhattisgarh, India.MethodologyA record review of tuberculosis (TB) patients registered in 2009 using a structured proforma from two sources, Tuberculosis and Laboratory Register, was undertaken in the six districts of Chhattisgarh, India.ResultsIn smear positive cases, of 10,048 follow-up examinations, 45 (0.5%) were found to be smear positive only on the second sputum when the result of the first sample was negative. In smear negative pulmonary and extra pulmonary TB patients, of 6,206 follow-up smear examinations, 11(0.2%) were found to be smear positive.ConclusionsThe incremental yield of a second smear examination was very low, indicating that examination of one sputum sample is enough during follow-up among TB patients. There is insufficient yield to support sputum smear microscopy for monitoring smear negative pulmonary TB and extra pulmonary TB patients. These results indicate that the follow-up smear microscopy can be substantially simplified with favourable resource implications.