Application of finite element models to eddy current probe design for aircraft inspection

Eddy current nondestructive testing (NDT) methods are used extensively in the inspection of aircraft structures. Improvements and innovations in probe design are constantly required for detection of flaws in complex multilayer aircraft structures. This thesis investigates alternate designs of eddy current probes for addressing some of these problems;An important aspect of probe design is the capability to simulate probe performance. Numerical computation and visualization of the electromagnetic fields can provide valuable insight into the design of new probes. Finite element methods have been used in this dissertation to numerically compute the electromagnetic fields associated with the probe coils, and the eddy current probe signals. A major contribution of this thesis is development of techniques to reduce the computer resource requirement in the finite element modeling: of the eddy current phenomenon;The first flaw detection problem is addressed by focusing the flux of the probe using active compensation techniques. A novel eddy current probe using a combination of coils is proposed and studied using: the 3D model simulation. The probe consists of two current carrying concentric coils to detect flaws closer to the sample edges;Detection of defects in second and third layer of samples has been demonstrated using: the remote field eddy current (RFEC) method. In the RFEC method the pickup coils are located in the far field region which leads to a large volume to be modeled numerically with large number of elements. A method involving partitioning the volume in the 3D finite element model is demonstrated for the RFEC detection of defects;Magneto-optic/eddy current imaging (MOI) techniques have shown considerable promise in the detection of corrosion in the second layer. MOI is a nondestructive testing method currently in use in aircraft frame inspection and it involves optically sensing the magnetic field induced by the eddy currents in the test sample. A numerical model for simulating the MOI test geometry has been developed as an aid for tool optimization;In the modeling work, effort is focused towards reducing the computation time and utilize larger computer memory the programs that solve the linear equations obtained in the finite element method have been parallelized using the message passing interface (MPI) to run on a cluster of computers

Effect of maternal education on antenatal care utilization, maternal and perinatal outcome in a tertiary care hospital

Background: Antenatal Care (ANC) utilization facility is available but poorly utilized because of many factors which play indirect role in inadequate utilization of antenatal care facility: low social status of women in the society, less opportunity for basic education, less ability to make decisions. Therefore, the present study is an attempt to study the effect of maternal education on antenatal care utilization, maternal and perinatal outcome in a tertiary care hospital.Methods: A prospective study was carried out on 525 cases delivered during period of one year at Dayanand Medical College and Hospital, Ludhiana, Punjab, India; a tertiary care hospital catering both urban and rural population. All cases were categorized into two groups: booked and unbooked. The age, parity and education of each patient in booked and unbooked cases was noted. Further, its impact on antenatal care utilization, maternal and perinatal outcome was studied.Results: On studying education pattern, among illiterate subjects 50% were booked and 50% were unbooked; For graduate and above were 80.6% and 19.4%respectively. Among mothers who were illiterate 90.9% had low birth weight babies and 13.6% had stillborn. Among those graduates and above 38.7% had low birth weight babies,1.5 % stillborn and 1.2% neonatal deaths.Conclusions: The educational status of the women came out as a significantly important variable and predictor of perinatal outcome. Hence, whole hearted efforts should be directed in educating women population and also improving health care facilities in rural areas to provide early referral to higher centers

Optimization of Self-Nulling Eddy Current Probe for the Detection of Shallow Fatigue Cracks

The Self-Nulling Eddy Current Probe has been the focus of much research during the past several years [1–7]. Developed under NASA’s Airframe Structural Integrity Program, past research has focused on applying the Self-Nulling Probe technology to the inspection of damage to thin aluminum airframe skins. As a result of this work prototype fatigue crack detectors, single and multi-layer thickness gauges, and a system for the detection of cracks under installed fasteners have been developed[l–2,5–7]. The probe has also been successful at detecting surface flaws in thick bulk materials, for which a commercial instrument has been produced and marketed by Kramer Branson, Inc.-This paper will explore the fatigue crack detection mechanism of the Self-Nulling Probe for shallow flaws in thick materials as compared to that of through cracks in thin skins. The resulting change in the performance of the Self-Nulling Probe will then be detailed, and proposed modifications to optimize the performance of the probe for the detection of shallow fatigue cracks enumerated

Psychiatric comorbidities among people with epilepsy: A population-based assessment in disadvantaged communities

Psychiatric disorders are frequent among people with epilepsy but often under-recognized. The diagnosis and treatment of these disorders in low- and low-middle-income countries (LMICs) are challenging. METHODS: This cross-sectional survey included people recruited during a community epilepsy screening program involving 59,509 individuals from poor communities in Ludhiana in Northwest India. Adults (age ≥18 years) with confirmed epilepsy on antiseizure medications were screened for depression and anxiety using the Neurological Disorders Depression Inventory for Epilepsy (NDDI-E) and Generalized Anxiety Disorder-7 (GAD-7) twice over two years of follow-up. They were later interviewed for symptoms using the Brief Psychiatric Rating Scale, which was then confirmed by assessments by an experienced psychiatrist. RESULTS: Of the 240 people with confirmed epilepsy, 167 (70%) were adults, of whom, 116 (70%) eventually participated in the study. The NDDI-E with a cut-off of 15 identified depression in 14 (12%) of 116 people after one year of follow-up and 17 (15%) at two years. The GAD-7 using a cut-off of 6 identified 22 (19%) at one year and 32 (28%) with anxiety at two years. The area under the curves for NDDI-E was estimated as 0.62 (95%CI, 0.51-0.73; SE: 0.06; p = 0.04) and for GAD-7 as 0.62 (95%CI, 0.46-0.78; SE: 0.08; p = 0.12). Brief Psychiatric Rating Scale identified 63 (54%) people with psychiatric symptoms, for whom, a psychiatric diagnosis was confirmed in 60 (52%). A psychiatric diagnosis was associated with education below high school [Odds Ratio (OR): 2.59, 95%CI, 1.12-5.1; p = 0.03], later age of seizure onset (OR, 1.05, 95%CI: 1.0-1.10; p = 0.04), seizure frequency of at least one/year at enrolment (OR, 2.36, 95%CI: 1.0-5.58; p = 0.05) and the use of clobazam (OR, 5.09, 95%CI, 1.40-18.42; p = 0.01). CONCLUSION: Depression and anxiety are common in people with epilepsy. Our findings underscore the low yields of screening instruments, NDDI-E and GAD-7, and comparatively better professionally-administered diagnostic assessments in resource-limited settings in LMICs. Moreover, previously established cut-offs do not apply to the community studied

A cluster-randomised trial comparing home-based primary health care and usual clinic care for epilepsy in a resource-limited country

OBJECTIVE: To ascertain whether home-based care with community and primary healthcare workers' support improves adherence to antiseizure medications, seizure control, and quality of life over routine clinic-based care in community samples of people with epilepsy in a resource-poor country. METHODS: Participants included consenting individuals with active epilepsy identified in a population survey in impoverished communities. The intervention included antiseizure medication provision, adherence reinforcement and epilepsy self- and stigma management guidance provided by a primary health care-equivalent worker. We compared the intervention group to a routine clinic-based care group in a cluster-randomised trial lasting 24 months. The primary outcome was antiseizure medication adherence, appraised from monthly pill counts. Seizure outcomes were assessed by monthly seizure aggregates and time to first seizure and impact by the Personal Impact of Epilepsy scale. RESULTS: Enrollment began on 25.09.2017 and was complete by 24.07.2018. Twenty-four clusters, each comprising ten people with epilepsy, were randomised to either home- or clinic-care. Home-care recepients were more likely to have used up their monthly-dispensed epilepsy medicine stock (Regression Coefficient: 0.585; 95% Confidence Intervals, 0.289 to 0.881; P=0.001) and had fewer seizures (Regression coefficient: -2.060; 95%CI, -3.335 to -0.785; P=0.002). More people from clinic-care (n=44; 37%) than home-care (n=23; 19%) exited the trial (P=0.003). The time to first seizure, adverse effects and the personal impact of epilepsy were similar in the two arms. SIGNIFICANCE: Home care for epilepsy compared to clinic care in resource-limited communities improves medication adherence and seizure outcomes and reduces the secondary epilepsy treatment gap

Healthcare Seeking Behaviour of Hospitalised COVID-19 Patients During Second Wave in Tertiary Care Hospital of Northern India

Background: The Coronavirus Disease (COVID-19) pandemic continues its deadly reign all over the world. Devising effective strategies for detecting and controlling the infection has become ever more critical. Effective prevention and control of the pandemic is entirely dependent on human behavior in terms of practicing preventive and curative measures. During the second wave of COVID-19, people’s perceptions of preventive and curative measures changed. Objective: To study healthcare-seeking behavior of hospitalized COVID-19 patients. Methods: Hospitalized patients due to COVID-19 in the month of March, April and May of 2021 were included in the study. Their attendants/close relatives were contacted telephonically to know about the admitted patients’ healthcare-seeking behavior. Verbal consent was taken from attendants before the commencement of the interview, followed by informing them about the purpose of the interview. Results: Amongst the subjects, there were more males than females (67.5 vs 32.4%), age ranged between 18 to 88 with a mean value of 56.61 ± 14.7 years. Self-medication was significantly associated with study subjects’ mortality (p=0.03). Conclusion: Elderly people were having higher mortality rate than their younger counterparts. People were hesitant to visit primary care physicians after having symptoms of COVID-19

Mask Use pattern, Public Perception and Barriers to Effective Mask Usage-A battle far from over

Background & Objective: Proper mask wearing reduces the transmissibility and risk of Covid-19 infection still compliance to mask use is low. This study was conducted to observe the mask usage pattern, perception and barriers to effective mask usage (EMU). Settings and Design: This cross-sectional study was conducted in collaboration with district police administration to observe mask usage pattern in various crowded places. Methods and Material: Participants from general public (n=6995) in 10 preselected areas of city were observed and then interviewed about their perceptions about EMU. Indirect observation of EMU was also done by screening CCTV footage, followed by another set of observation at same places after conducting a health education campaign. Data was entered in Microsoft excel and analyzed using SPSS. P value <0.05 was considered significant. Results: EMU was seen in nearly 62% participants. Younger age, native population, education above matric, persons driving two & four wheelers, had significantly higher compliance. During CCTV observation, EMU was 57.5%, and was highest near public places, roads and intersections while lowest near bus stand and religious places. Some improvement in compliance was seen after health education at these places. Breathing difficulty, no use of wearing mask and feeling uncomfortable were the most common reasons given by participants for non-compliance.Conclusions: EMU was lower in elderly, migrants, less educated, unemployed, daily wage workers, so these groups should be especially sensitized about preventive measures. There is need for extensive public education to bring out behavioral change regarding proper mask wearing to control this pandemic and prevent further waves

How sustained is sustained viral response in patients with hepatitis C virus infection?

Abstract Background Sustained virological response (SVR) is achieved in a high proportion of patients with chronic hepatitis C infection, particularly those with genotype 2 or 3 HCV infection. However, data on long-term durability of virological response in patients who achieve SVR are limited. Aim To evaluate the long-term durability of virological response in patients who have achieved SVR with interferon-based combination therapy. Methods One hundred patients with chronic HCV infection who had obtained SVR after IFN and ribavirin combination therapy were followed up for up to 8 years with annual HCV RNA testing. Results During a followed up of 6 months to 8 years, 8 of 100 patients with initial SVR developed late relapse of HCV infection. Relapse was more common in patients who had cirrhosis (5/28 [18%] vs. (3/72 [4%] with no cirrhosis; p=0.037). Conclusion SVR is durable in most patients, but some patients do have late relapse; long term follow up may be particularly important in a subset of patients with HCV infection who have liver cirrhosis

Prevalence of sustained hypertension and obesity among urban and rural adolescents: a school-based, cross-sectional study in North India.

OBJECTIVE: Recent data on sustained hypertension and obesity among school-going children and adolescents in India are limited. This study evaluates the prevalence of sustained hypertension and obesity and their risk factors among urban and rural adolescents in northern India. SETTING: A school-based, cross-sectional survey was conducted in the urban and rural areas of Ludhiana, Punjab, India using standardised measurement tools. PARTICIPANTS: A total of 1959 participants aged 11-17 years (urban: 849; rural: 1110) were included in this school-based survey. PRIMARY AND SECONDARY OUTCOME MEASURES: To measure sustained hypertension among school children, two distinct blood pressure (BP) measurements were recorded at an interval of 1 week. High BP was defined and classified into three groups as recommended by international guidelines: (1) normal BP: 95th percentile. The Indian Academy of Pediatrics classification was used to define underweight, normal, overweight and obesity as per the body mass index (BMI) for specific age groups. RESULTS: The prevalence of sustained hypertension among rural and urban areas was 5.7% and 8.4%, respectively. The prevalence of obesity in rural and urban school children was 2.7% and 11.0%, respectively. The adjusted multiple regression model found that urban area (relative risk ratio (RRR): 1.7, 95% CI 1.01 to 2.93), hypertension (RRR: 7.4, 95% CI 4.21 to 13.16) and high socioeconomic status (RRR: 38.6, 95% CI 16.54 to 90.22) were significantly associated with an increased risk of obesity. However, self-reported regular physical activity had a protective effect on the risk of obesity among adolescents (RRR: 0.4, 95% CI 0.25 to 0.62). Adolescents who were overweight (RRR: 2.66, 95% CI 1.49 to 4.40) or obese (RRR: 7.21, 95% CI 4.09 to 12.70) and reported added salt intake in their diet (RRR: 4.90, 95% CI 2.83 to 8.48) were at higher risk of hypertension. CONCLUSION: High prevalence of sustained hypertension and obesity was found among urban school children and adolescents in a northern state in India. Hypertension among adolescents was positively associated with overweight and obesity (high BMI). Prevention and early detection of childhood obesity and high BP should be strengthened to prevent the risk of cardiovascular diseases in adults