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1.
Heliyon ; 10(5): e26665, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38486727

ABSTRACT

This research introduces the Multi-Objective Liver Cancer Algorithm (MOLCA), a novel approach inspired by the growth and proliferation patterns of liver tumors. MOLCA emulates the evolutionary tendencies of liver tumors, leveraging their expansion dynamics as a model for solving multi-objective optimization problems in engineering design. The algorithm uniquely combines genetic operators with the Random Opposition-Based Learning (ROBL) strategy, optimizing both local and global search capabilities. Further enhancement is achieved through the integration of elitist non-dominated sorting (NDS), information feedback mechanism (IFM) and Crowding Distance (CD) selection method, which collectively aim to efficiently identify the Pareto optimal front. The performance of MOLCA is rigorously assessed using a comprehensive set of standard multi-objective test benchmarks, including ZDT, DTLZ and various Constraint (CONSTR, TNK, SRN, BNH, OSY and KITA) and real-world engineering design problems like Brushless DC wheel motor, Safety isolating transformer, Helical spring, Two-bar truss and Welded beam. Its efficacy is benchmarked against prominent algorithms such as the non-dominated sorting grey wolf optimizer (NSGWO), multiobjective multi-verse optimization (MOMVO), non-dominated sorting genetic algorithm (NSGA-II), decomposition-based multiobjective evolutionary algorithm (MOEA/D) and multiobjective marine predator algorithm (MOMPA). Quantitative analysis is conducted using GD, IGD, SP, SD, HV and RT metrics to represent convergence and distribution, while qualitative aspects are presented through graphical representations of the Pareto fronts. The MOLCA source code is available at: https://github.com/kanak02/MOLCA.

2.
Heliyon ; 10(4): e26369, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38404848

ABSTRACT

In this study, we tackle the challenge of optimizing the design of a Brushless Direct Current (BLDC) motor. Utilizing an established analytical model, we introduced the Multi-Objective Generalized Normal Distribution Optimization (MOGNDO) method, a biomimetic approach based on Pareto optimality, dominance, and external archiving. We initially tested MOGNDO on standard multi-objective benchmark functions, where it showed strong performance. When applied to the BLDC motor design with the objectives of either maximizing operational efficiency or minimizing motor mass, the MOGNDO algorithm consistently outperformed other techniques like Ant Lion Optimizer (ALO), Ion Motion Optimization (IMO), and Sine Cosine Algorithm (SCA). Specifically, MOGNDO yielded the most optimal values across efficiency and mass metrics, providing practical solutions for real-world BLDC motor design. The MOGNDO source code is available at: https://github.com/kanak02/MOGNDO.

3.
Sci Rep ; 14(1): 1816, 2024 Jan 20.
Article in English | MEDLINE | ID: mdl-38245654

ABSTRACT

The exponential distribution optimizer (EDO) represents a heuristic approach, capitalizing on exponential distribution theory to identify global solutions for complex optimization challenges. This study extends the EDO's applicability by introducing its multi-objective version, the multi-objective EDO (MOEDO), enhanced with elite non-dominated sorting and crowding distance mechanisms. An information feedback mechanism (IFM) is integrated into MOEDO, aiming to balance exploration and exploitation, thus improving convergence and mitigating the stagnation in local optima, a notable limitation in traditional approaches. Our research demonstrates MOEDO's superiority over renowned algorithms such as MOMPA, NSGA-II, MOAOA, MOEA/D and MOGNDO. This is evident in 72.58% of test scenarios, utilizing performance metrics like GD, IGD, HV, SP, SD and RT across benchmark test collections (DTLZ, ZDT and various constraint problems) and five real-world engineering design challenges. The Wilcoxon Rank Sum Test (WRST) further confirms MOEDO as a competitive multi-objective optimization algorithm, particularly in scenarios where existing methods struggle with balancing diversity and convergence efficiency. MOEDO's robust performance, even in complex real-world applications, underscores its potential as an innovative solution in the optimization domain. The MOEDO source code is available at: https://github.com/kanak02/MOEDO .

4.
J Pediatr Urol ; 13(5): 489.e1-489.e5, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28284732

ABSTRACT

INTRODUCTION: The adoption of robot-assisted laparoscopic (RAL) procedures in the field of urology has occurred rapidly, but is, to date, without pediatric-specific instrumentation. Surgical fog is a significant barrier to safe and efficient laparoscopy. This appears to be a significant challenge when adapting three-dimensional 8.5-mm scopes to use in pediatric RAL surgery. The objective of the present study was to compare matched controls from a prospectively collected database to procedures that were performed utilizing special equipment and a protocol to minimize surgical fog in pediatric RAL procedures. METHODS: A prospectively collected database of all patients who underwent RAL pediatric urology procedures was used to compare: procedure, age, sex, American Society of Anesthesiologists score, weight, console time, number of times the camera was removed to clean the lens during a procedure, length of hospital stay, and morphine equivalents required in the postoperative period. A uniquely developed protocol was used, it consisted of humidified (95% relative humidity) and warmed CO2 gas (95 °F) insufflation via Insuflow® on a working trocar, with active smoke evacuation via PneuVIEW®XE on the opposite working trocar with a gas pass through of 3.5-5 l/min. The outcomes were compared with matched controls (Summary Fig). RESULTS: The novel gas protocol was utilized in 13 procedures (five pyeloplasties, two revision pyeloplasties, three ureteroureterostomies (UU), three nephrectomies) and compared with 13 procedures (six pyeloplasties, one revision pyeloplasty, three UU, three nephrectomies) prior to the protocol development. There was no statistical difference in age (P = 0.78), sex (P = 0.11), ASA score (P = 1.00) or weight (P = 0.69). There were no open conversions, ≥Grade 2 Clavien complications, or readmissions within 30 days in either group. CONCLUSIONS: This novel gas protocol yielded a statistically significant reduction in procedure time, by decreasing the number of times the camera was required to be pulled during the case by more than five occurrences, and saved approximately 35 min on average per case.


Subject(s)
Laparoscopy/methods , Operative Time , Patient Safety , Pneumoperitoneum, Artificial/methods , Robotic Surgical Procedures/methods , Case-Control Studies , Child , Child, Preschool , Databases, Factual , Female , Humans , Humidity/prevention & control , Intraoperative Complications/prevention & control , Laparoscopy/adverse effects , Male , Pneumoperitoneum, Artificial/adverse effects , Prognosis , Prospective Studies , Robotic Surgical Procedures/adverse effects , Treatment Outcome , Urologic Diseases/diagnosis , Urologic Diseases/surgery , Urologic Surgical Procedures/adverse effects , Urologic Surgical Procedures/methods
5.
Osteoporos Int ; 26(9): 2291-8, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25807914

ABSTRACT

UNLABELLED: Age was a modifier of the independent association between hyponatremia and osteoporosis (OP). Risk of OP was the highest in the youngest age group as compared to older patients. A longer duration of hyponatremia revealed a similar association with OP in all anatomical sites. INTRODUCTION: Epidemiologic studies provide conflicting results on the relationship between hyponatremia and OP. Our aim is to test the modification effect of age on the relationship between hyponatremia and OP at various anatomical sites in a large patient population. METHODS: This is a cross-sectional observation of consecutive patients with available bone densitometry, demographic, clinical, and laboratory data from 2001 to 2013 at a single center. OP was defined as a bone mineral density of ≤2.5 standard deviations below the mean peak bone mass of young, healthy adults. Hyponatremia was defined as serum sodium ≤135 mmol/L. Multiple logistic regressions were used to calculate adjusted odds ratio (OR). RESULTS: Overall, 24,784 patients were included. There were 4549 males (18.4 %). Hyponatremia was present in 703 patients (2.8 %), femoral neck OP in 2603 (10.5 %), total hip OP in 1885 (7.5 %), and lumbar OP in 4830 (19.5 %). Total hip OP occurred in 17.6 % (n = 124) of patients with hyponatremia as compared to 6.6 % (n = 880) of patients with sodium level of "140-145" mmol/L (P < 0.001). After multivariable adjustments, hyponatremia was associated with 2.46-fold higher odds of total hip OP (95 % CI, 1.36 to 4.46) in age <55 years, 1.96-fold (1.13 to 3.41) in age 55 to 67 years, and 1.55-fold (1.13 to 2.12) in age >67 years (age-sodium category interaction P value = 0.002). CONCLUSIONS: Age appeared as a modifier of the independent association between hyponatremia and OP. Risk of OP was the highest in the youngest age group as compared to older patients.


Subject(s)
Hyponatremia/complications , Osteoporosis/etiology , Age Factors , Aged , Bone Density/physiology , Cross-Sectional Studies , Female , Femur Neck/physiopathology , Hip Joint/physiopathology , Humans , Hyponatremia/epidemiology , Hyponatremia/physiopathology , Lumbar Vertebrae/physiopathology , Male , Michigan/epidemiology , Middle Aged , Osteoporosis/epidemiology , Osteoporosis/physiopathology , Risk Factors , Time Factors
6.
Eur Respir J ; 38(1): 176-83, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21148225

ABSTRACT

The composite physiologic index (CPI) was derived to represent the extent of fibrosis on high-resolution computed tomography (HRCT), adjusting for emphysema in patients with idiopathic pulmonary fibrosis (IPF). We hypothesised that longitudinal change in CPI would better predict mortality than forced expiratory volume in 1 s (FEV(1)), forced vital capacity (FVC) or diffusing capacity of the lung for carbon monoxide (D(L,CO)) in all patients with IPF, and especially in those with combined pulmonary fibrosis and emphysema (CPFE). Cox proportional hazard models were performed on pulmonary function data from IPF patients at baseline (n = 321), 6 months (n = 211) and 12 months (n = 144). Presence of CPFE was determined by HRCT. A five-point increase in CPI over 12 months predicted subsequent mortality (HR 2.1, p = 0.004). At 12 months, a 10% relative decline in FVC, a 15% relative decline in D(L,CO) or an absolute increase in CPI of five points all discriminated median survival by 2.1 to 2.2 yrs versus patients with lesser change. Half our cohort had CPFE. In patients with moderate/severe emphysema, only a 10% decline in FEV(1) predicted mortality (HR 3.7, p = 0.046). In IPF, a five-point increase in CPI over 12 months predicts mortality similarly to relative declines of 10% in FVC or 15% in D(L,CO). For CPFE patients, change in FEV(1) was the best predictor of mortality.


Subject(s)
Emphysema/complications , Idiopathic Pulmonary Fibrosis/diagnosis , Lung/physiology , Pulmonary Fibrosis/complications , Aged , Carbon Monoxide/chemistry , Diffusion , Emphysema/mortality , Female , Fibrosis , Forced Expiratory Volume , Humans , Idiopathic Pulmonary Fibrosis/mortality , Longitudinal Studies , Male , Middle Aged , Proportional Hazards Models , Pulmonary Fibrosis/mortality , Regression Analysis , Tomography, X-Ray Computed/methods , Vital Capacity
8.
Acta Radiol ; 49(8): 870-5, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18618350

ABSTRACT

BACKGROUND: The accuracy of the number of high-resolution computed tomography (HRCT) images necessary to diagnose diffuse lung disease (DLD) is not well established. PURPOSE: To evaluate the impact of HRCT sampling frequency on reader confidence and accuracy for diagnosing DLD. MATERIAL AND METHODS: HRCT images of 100 consecutive patients with proven DLD were reviewed. They were: 48 usual interstitial pneumonia, 22 sarcoidosis, six hypersensitivity pneumonitis, five each of desquamative interstitial pneumonitis, eosinophilic granulomatosis, and lymphangioleiomyomatosis, and nine others. Inspiratory images at 1-cm increments throughout the lungs and three specified levels formed complete and limited examinations. In random order, three experts (readers 1, 2, and 3) ranked their top three diagnoses and rated confidence for their top diagnosis, independently and blinded to clinical information. RESULTS: Using the complete versus limited examinations for correct first-choice diagnosis, accuracy for reader 1 (R1) was 81% versus 80%, respectively, for reader 2 (R2) 70% versus 70%, and for reader 3 (R3) 64% versus 59%. Reader accuracy within their top three choices for complete versus limited examinations was: R1 91% versus 91% of cases, respectively, R2 84% versus 83%, and R3 79% versus 72% of cases. No statistically significant differences were found between the diagnosis methods (P=0.28 for first diagnosis and P=0.17 for top three choices). The confidence intervals for individual raters showed considerable overlap, and the point estimates are almost identical. The mean interreader agreement for complete versus limited HRCT for both top and top three diagnoses were the same (moderate and fair, respectively). The mean intrareader agreement between complete and limited HRCT for top and top three diagnoses were substantial and moderate, respectively. CONCLUSION: Overall reader accuracy and confidence in diagnosis did not significantly differ when fewer or more HRCT images were used.


Subject(s)
Lung Diseases/diagnosis , Lung/diagnostic imaging , Tomography, X-Ray Computed/methods , Adult , Aged , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Observer Variation , Reproducibility of Results , Sample Size
9.
Biomed Pharmacother ; 59 Suppl 1: S152-7, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16275485

ABSTRACT

Overswinging or CHAT (brief for Circadian Hyper-Amplitude-Tension), that is an excessive circadian variation in blood pressure (BP), has been associated with a large increase in cardiovascular disease risk, present even in the absence of an elevated BP itself. This usually asymptomatic condition is usually overlooked by current practice based on spot-checks, because to be diagnosed, measurements need to be taken around-the-clock, preferably for 7 days at the outset. Once diagnosed, however, a usual circadian BP pattern can be restored by means of certain non-pharmacologic or pharmacologic interventions timed appropriately. Thereby, it is possible to reduce the risk of cardiovascular morbidity and mortality, cerebral ischemic events and nephropathy in particular. For the preparation of guidelines regarding the diagnosis of BP disorders and for the institution of primary as well as secondary preventive measures, it is important to know what the incidence of CHAT is on a global basis. We found 191 cases of CHAT among 1602 mostly 7-day/24-h BP profiles, obtained from several centers in different countries participating in an ongoing project on the BIOsphere and the COSmos (BIOCOS). CHAT incidence is about the same between men and women, but it is diagnosed more often among patients with borderline hypertension or with glucose intolerance. It is also more common among MESOR-hypertensive than among MESOR-normotensive individuals. Priority should be given to the development of an unobtrusive and affordable device to automatically monitor BP and to analyze the data as-one-goes, so that cardiovascular disease risk can be prevented.


Subject(s)
Blood Pressure/physiology , Circadian Rhythm/physiology , Hypertension/diagnosis , Adult , Female , Glucose Intolerance/complications , Heart Rate/physiology , Humans , Hypertension/epidemiology , Japan/epidemiology , Male , Risk Assessment , Rural Population , Stroke/epidemiology , Urban Population
10.
Biomed Pharmacother ; 59 Suppl 1: S76-85, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16275512

ABSTRACT

Time structurally (chronomically) interpreted half-hourly monitoring of blood pressure (BP) and heart rate (HR) for at least 7 days and preferably for 17 days is recommended, separately for a diagnosis of BP disorders and when necessary again for the same or longer spans for treatment, whenever a positive diagnosis of a disorder is made. In this study, 30 clinically healthy subjects underwent 7-day monitoring and provided a series of findings, including the detection of Circadian Hyper-Amplitude-Tension (CHAT), that is blood pressure overswinging, which carries a high risk of hard cardiovascular events. The results specifically bear upon south-east Asian-Indian immigrants. They show that cardiovascular disease risk increases with age, with a positive family history of hypertension and/or other cardiovascular diseases and even with the duration of stay in the USA. A relation to body mass index is also shown. Such monitoring for prehabilitation may eventually reduce the need for rehabilitation.


Subject(s)
Blood Pressure/physiology , Chronobiology Phenomena , Circadian Rhythm/physiology , Heart Rate/physiology , Periodicity , Adult , Aging/physiology , Asian , Blood Pressure Monitoring, Ambulatory , Body Mass Index , California/epidemiology , Female , Humans , India/epidemiology , India/ethnology , Male , Regression Analysis
11.
Arch Dis Child ; 88(5): 378, 2003 May.
Article in English | MEDLINE | ID: mdl-12716701
12.
Arch Dis Child ; 88(4): 302, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12651753

ABSTRACT

We suggest a formula to aid diagnosis of hypertension in children and adolescents in general practice. The values obtained from this formula were found to correlate well with the values in the charts recommended by the Update of 1987 Task Force report on high blood pressure in children and adolescents.


Subject(s)
Hypertension/diagnosis , Adolescent , Blood Pressure , Child , Child, Preschool , Family Practice/methods , Female , Humans , Infant , Male , Reference Values , Time Factors
13.
Eur J Gastroenterol Hepatol ; 13(11): 1375-8, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11692066

ABSTRACT

The causative association between Helicobacter pylori and gastric mucosal inflammation is well established. The inflammatory process leads to the acquisition of mucosa-associated lymphoid tissue (MALT) by the stomach. Evidence links H. pylori gastritis with the development of low-grade primary gastric lymphoma with a phenotype specific for lymphoma of MALT type. It is now accepted that primary low-grade MALT lymphomas regress with H. pylori eradication therapy. However, the response of primary, diffuse, large-cell gastric lymphoma to H. pylori eradication therapy is still not established. We report a case of a primary high-grade gastric lymphoma regressing after H. pylori eradication therapy.


Subject(s)
Helicobacter Infections/complications , Helicobacter Infections/drug therapy , Helicobacter pylori , Lymphoma, B-Cell/etiology , Neoplasm Regression, Spontaneous , Omeprazole/analogs & derivatives , Stomach Neoplasms/etiology , 2-Pyridinylmethylsulfinylbenzimidazoles , Aged , Female , Humans , Lansoprazole , Lymphoma, B-Cell/pathology , Omeprazole/therapeutic use , Stomach Neoplasms/pathology
14.
Phys Rev Lett ; 84(20): 4581-4, 2000 May 15.
Article in English | MEDLINE | ID: mdl-10990745

ABSTRACT

A tight-binding representation of the kicked Harper model is used to obtain an integrable semiclassical Hamiltonian consisting of "quantized" bands of orbits. New bands appear when renormalized Harper parameters exceed integer multiples of pi/2. Orbits with frequencies commensurate with the kicking frequency are shown to correlate with classical accelerator modes in the original kicked problem. Signatures of this superdiffusive and, in our view, resonant transport are seen in both classical and quantum behavior. An important feature of our analysis is the emergence of a natural scaling relating classical and quantum couplings which is necessary for establishing correspondence.

15.
Article in English | MEDLINE | ID: mdl-11969717

ABSTRACT

We present evidence that anomalous transport in the classical standard map results in strong enhancement of fluctuations in the localization length of quasienergy states in the corresponding quantum dynamics. This generic effect occurs even far from the semiclassical limit and reflects the interplay of local and global quantum suppression mechanisms of classically chaotic dynamics. Possible experimental scenarios are also discussed.

16.
Article in English | MEDLINE | ID: mdl-11969782

ABSTRACT

We address the issue of fluctuations, about an exponential line shape, in a pair of one-dimensional kicked quantum systems exhibiting dynamical localization. An exact renormalization scheme establishes the fractal character of the fluctuations and provides a method to compute the localization length in terms of the fluctuations. In the case of a linear rotor, the fluctuations are independent of the kicking parameter k and exhibit self-similarity for certain values of the quasienergy. For given k, the asymptotic localization length is a good characteristic of the localized line shapes for all quasienergies. This is in stark contrast to the quadratic rotor, where the fluctuations depend upon the strength of the kicking and exhibit local "resonances." These resonances result in strong deviations of the localization length from the asymptotic value. The consequences are particularly pronounced when considering the time evolution of a packet made up of several quasienergy states.

17.
Article in English | MEDLINE | ID: mdl-11970223

ABSTRACT

We report a study of atomic motion in time-dependent optical potentials. We measure momentum transfer in parameter regimes for which the classical dynamics are chaotic, and observe the quantum suppression of chaos by dynamical localization. The high degree of control over the experimental parameters enables detailed comparisons with theoretical predictions, and opens new avenues for investigating quantum chaos.

18.
Phys Rev B Condens Matter ; 54(7): 4966-4973, 1996 Aug 15.
Article in English | MEDLINE | ID: mdl-9986459
19.
Phys Rev Lett ; 77(2): 263-266, 1996 Jul 08.
Article in English | MEDLINE | ID: mdl-10062407
20.
Phys Rev Lett ; 76(26): 4907-4910, 1996 Jun 24.
Article in English | MEDLINE | ID: mdl-10061410
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