Lattice and QR decomposition-based algorithms for recursive least squares adaptive nonlinear filters

Journal ArticleThis paper presents a lattice structure for adaptive Volterra systems. The stucture is applicable to arbitrary planes of support of the Volterra kernels. A fast least squares lattice and a fast QR-lattice adaptive nonlinear filtering algorithms based on the lattice structure are also presented. These algorithms share the fast convergence property of fast least squares transversal Volterra filters; however, unlike the transversal filters they do not suffer from numerical instability

Lattice algorithms for recursive least squares adaptive second-order volterra filtering

Journal ArticleThis paper presents two computationally efficient recursive least-square (RLS) lattice algorithms for adaptive nonlinear filtering based on a truncated second-order Volterra system model. The lattice formulation transforms the nonlinear filtering problem into an equivalent multichannel, linear filtering problem and then generalizes the lattice solution to the nonlinear filtering problem. One of the algorithms is a direct extension of the conventional RLS lattice adaptive linear filtering algorithm to the nonlinear case. The other algorithms is based on the QR decomposition of the prediction error covariance matrices using orthogonal transformations. Several experiments demonstrating and comparing the properties of the two algorithms in finite and "infinite" precision environments are included in the paper. The results indicate that both the algorithms retain the fast convergence behavior of the RLS Volterra filters and are numerically stable

Association of Physical Activity with Co-morbid Conditions in Geriatric Population

To find out association of physical activity with co-morbid conditions in geriatric population, a cross-sectional study was conducted in different cties of Pakistan in 2015. A total of 114 participants were inducted by non-probability convenience sampling technique. Data was collected after informed verbal consent by a validated questionnaire that is Rapid Assessment of Physical Activity (RAPA). Participants were categorized into two groups i.e. physically active and physically inactive. Data was entered and analyzed in SPSS version 20. There were 66 (57.9%) males and 48 (42.1%) females with mean age of 57.04±7.348 years. Among hypertensive individuals (n=43, 37.7%) there were 39 (90.7%) physically inactive, among individuals having angina (n=17, 14.9%) there were 15 (88.2%) physically inactive. Out of 37 (32.5%) diabetics, 35 (94.6%) were physically inactive. Among individuals suffering from arthritis (n=40, 35.1%), there were 38 (95%) physically inactive. A significant association was found between physical activity and diabetes and arthritis with p-value of 0.048 and 0.029 respectively. Physical activity is significantly associated with diabetes and arthritis in geriatric population. Adequate physical activity should be performed to reduce the risk of co-morbid conditions and improve the quality of life in geriatric population

Non-Local Deformation of a Supersymmetric Field Theory

In this paper, we will analyse a supersymmetric field theory deformed by generalized uncertainty principle and Lifshitz scaling. It will be observed that this deformed supersymmetric field theory contains non-local fractional derivative terms. In order to construct such deformed N=1 supersymmetric theory, a harmonic extension of functions will be used. However, the supersymmetry will be only preserved for a free theory and will be broken by the inclusion of interaction terms.Comment: 12 pages, pulished versio

Customized vacuum assisted closure therapy of wounds as a simple and cost-effective technique of wound closure-a prospective observational study from underdeveloped world

Background: Aim of the study was to study the efficacy and cost-effectiveness of indigenously designed customized vacuum assisted closure (VAC) of wounds in our patients. The management of difficult to heal wounds has been the main force that led to the development of advanced gadgets for their management. The technique of vacuum assisted closure has revolutionized the management of difficult to heal wounds and delivers better results as compared to conventional technique. Our aim was to assess the efficacy and cost effectiveness of customized VAC therapy.Methods: This prospective study was conducted in the department of surgery and allied specialties, GMC Srinagar, from June 2018 and September 2020. During this period, 80 patients were subjected to VAC therapy and were included in this study.Results: VAC dressing was used in 80 patients. 55 were males and 25 were females. Most of the wounds in our study were located over lower limbs (70%). RTA was the most common mode of injury followed by fall from height. After the VAC therapy, 78.8% patients were managed by STSG, 11.3% by flap cover, 6.3% by secondary suturing and 3.8% healed by secondary intention. Pain was experienced by 30% of the patients, 7.5% had hypoalbuminemia, 3.8% had surrounding skin maceration. The average total cost of the VAC therapy was 863.13 (±399.82) Indian rupees (11.76 USD). The mean duration of hospital stay for our patients was 22 days.Conclusions: Customized VAC Therapy has revolutionary potential in the management of the difficult to treat wounds as far as its safety, speed and cost effectiveness is considered especially in a setup of poor income nations like ours

Blood urea nitrogen as an early predictor of severity in acute pancreatitis

Background: Acute pancreatitis presents as acute abdominal pain and is usually associated with raised pancreatic enzyme levels in the blood or urine. Aims and objectives of the study was to evaluate the role of serial BUN measurement as an early prognostic marker of acute pancreatitis.Methods: From each patient detailed history was taken, general and systemic examination were done and relevant investigations were conducted. BUN was repeated after 24 hours and the change in the level of BUN was noted. Imaging in the form of CT after 72 hours of admission were performed in each patient. The severity of acute pancreatitis was gauged by modified CTSI and the same was compared to the change in BUN values over first 24 hours of admission.Results: Mean BUN values at ‘0’ hour in severe acute pancreatitis and non-severe acute pancreatitis were 31.91±6.79 and 15.44±5.95 mg/dl, respectively. The difference between the two groups was statistically significant with p value of <0.001. Similarly, the difference in BUN values at ‘24’ hours between the two groups was statistically significant. BUN value ≥23 mg/dl at ‘0’ hour was found to be the optimal cut off for determining the severity of pancreatitis with sensitivity of 91.3%. BUN ≥25 mg/dl at 24 hours was found to be the optimal cut-off for determining the severity of acute pancreatitis with sensitivity of 95.7%.Conclusions: BUN as a single marker for acute pancreatitis can be useful as it is easy to perform and cheap marker to predict severity without the need for complex calculations.

Electronic cigarettes use and perception amongst medical students: a cross sectional survey from Sindh, Pakistan

Objective: The manufacturers of electronic cigarettes (e-cigarettes) are actively marketing their product through electronic and social media. Undergraduate medical students are expected to have better knowledge and awareness as they directly interact with patients in their training, The purpose of this study is therefore, to determine knowledge, use and perception regarding e-cigarettes among medical students from Sindh, Pakistan. Results: A cross-sectional study was conducted between 1st July and 30th September 2016 at five different medical colleges situated in the second largest province of Sindh, Pakistan. The data was collected through a structured, self-administered questionnaire. Of the 500 students, the mean age was 21.5 ± 1.7 years and 58% were females. Over (65.6%) students were aware of e-cigarettes, 31 (6.2%) reported having used e-cigarettes, of whom 6 (1.2%) self-reported daily use. Users of conventional tobacco products were significantly more likely to have heard of e-cigarettes (87.6% vs 51.6%, p \u3c 0.001) and having used them (13.9% vs 1.3%, p \u3c 0.001). On multivariable logistic regression analysis we found a strong association of e-cigarette use with consumption of conventional cigarettes [OR: 10.6, 95% CI 3.6-30.8, p \u3c 0.001], use of smokeless tobacco products [OR: 7.9, 95% CI 2.7-23.4, p \u3c 0.001] however a weak association was observed for Shisha use [OR: 3.05, 95% CI 0.9-9.6, p = 0.05]

Synthesis of 3-[4-(2-furoyl)-1-piperazinyl]-N- (substituted)propanamides as promising antibacterial agents with mild cytotoxicity

Purpose: To evaluate the antibacterial activity and cytotoxicity of a series of molecules with amalgamation of furoyl, piperazine and amide moieties.Methods: New derivatives, namely 3-[4-(2-furoyl)-1-piperazinyl]-N-(substituted) propanamides, were synthesized and evaluated for their antibacterial activity and toxicity to mammalian cells. The synthesis was initiated by treating different aryl/aralkyl amines (1a-u) with 3-bromopropionyl chloride (2) to obtain the solid electrophiles 3a-u, which were collected by filtration. Thereafter, the different N-aryl/aralkyl-3- bromopropionamides (3a-u) and 2-furoyl-1-piperazine (4) at equimolar ratios were allowed to react in acetonitrile and in the presence of a base, K2CO3, to form the target compounds, 5a-u. Structural elucidation was carried out using EI-MS (electron impact mass spectrometry), IR (infrared) and 1H-NMR (proton nuclear magnetic resonance). The antibacterial activity of the synthesized compounds was evaluated against various bacterial strains. Furthermore, hemolysis was determined to assess cytotoxicity using bovine red blood cells.Results: Molecules 5g, 5a, 5p, 5g and 5i were found to be potent agents against S. aureus, S. typhi, P. aeruginosa, E. coli and B. subtilis with respective minimum inhibitory concentration (MIC) values of 8.34 ± 0.55, 8.37 ± 0.12, 8.65 ± 0.57, 8.97 ± 0.12 and 9.24 ± 0.50 μM, compared to 7.80 ± 0.19, 7.45 ± 0.58, 7.14 ± 0.58, 7.16 ± 0.58 and 7.29 ± 0.90 μM for the reference standard, ciprofloxacin. The most active compounds, 5a, 5g, 5i and 5p, showed a hemolysis of 15.48, 8.03, 5.52 and 4.35 %, respectively.Conclusion: The synthesized compounds exhibit good antibacterial activity. The hemolysis data indicate that these compounds have a low toxicity level. However, in vivo studies are required to ascertain their potentials as new drug candidates.Keywords: 4-(2-Furoyl)-1-piperazine, 1H-NMR, EI-MS, Antimicrobial activity, Hemolytic activit

Genetic Aberrations of the K-ras Proto-oncogene in Bladder Cancer in Kashmiri Population

PURPOSE: To assess the frequency of specific point mutations in the K-ras gene in a group of Kashmiri patients with bladder cancer. MATERIALS AND METHODS: We analyzed the incidence of K-ras exon 1 gene mutations in tumors and surgical margins in 60 patients with transitional cell carcinoma of varied clinical stages and histological grades using the polymerase chain reaction-single strand conformation polymorphism and DNA sequencing. RESULTS: A significant correlation was found between the K-ras, the lymph node status, and tumor recurrence (P < 0.05). Also, smokers and patients with higher tumor grade showed a significantly higher relative risk of developing K-ras mutations than the normal ones. CONCLUSION: K-ras exon 1 gene mutations were found with low frequency in the bladder cancer tumors from Kashmir valley, which suggests that K-ras gene might be involved in a sub-set of bladder tumors, but it needs further investigation on a larger cohort sample to authenticate the current findings