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Visual stimulus-induced gamma oscillations in electroencephalogram (EEG) recordings have been recently shown to be compromised in subjects with preclinical Alzheimer’s Disease (AD), suggesting that gamma could be an inexpensive biomarker for AD diagnosis provided its characteristics remain consistent across multiple recordings. Previous magnetoencephalography studies in young subjects have reported consistent gamma power over recordings separated by a few weeks to months. Here, we assessed the consistency of stimulus-induced slow (20–35 Hz) and fast gamma (36–66 Hz) oscillations in subjects (n = 40) (age: 50–88 years) in EEG recordings separated by a year, and tested the consistency in the magnitude of gamma power, its temporal evolution and spectral profile. Gamma had distinct spectral/temporal characteristics across subjects, which remained consistent across recordings (average intraclass correlation of ~0.7). Alpha (8–12 Hz) and steady-state-visually evoked-potentials were also reliable. We further tested how EEG features can be used to identify 2 recordings as belonging to the same versus different subjects and found high classifier performance (AUC of ~0.89), with temporal evolution of slow gamma and spectral profile being most informative. These results suggest that EEG gamma oscillations are reliable across sessions separated over long durations and can also be a potential tool for subject identification.

Visual stimulus-induced narrowband gamma oscillations in electroencephalogram (EEG) recordings have been recently shown to be compromised in subjects with Mild Cognitive Impairment or Alzheimer’s Disease (AD), suggesting that gamma could be an inexpensive and easily accessible biomarker for early diagnosis of AD. However, to use gamma as a biomarker, its characteristics should remain consistent across multiple recordings, even when separated over long intervals. Previous magnetoencephalography studies in young subjects have reported that gamma power remains consistent over recordings separated by a few weeks to months. Here, we assessed the consistency of slow (20-35 Hz) and fast gamma (36-66 Hz) oscillations induced by static full-field gratings in male (N=20) and female (N=20) elderly subjects (>49 years) in EEG recordings separated by more than a year, and tested the consistency in the magnitude of gamma power, its temporal evolution and spectral profile. Gamma oscillations had distinct spectral and temporal characteristics across subjects, which remained consistent across recordings (average intraclass correlation, ICC of ∼0.7). Alpha oscillations (8-12 Hz) and steady-state-visually-evoked-potentials (SSVEPs) were also found to be reliable. We further tested how EEG features can be used to identify two recordings as belonging to the same versus different subjects and found high classifier performance (area under ROC curve of ∼0.89), with the temporal evolution of slow gamma and spectral profile emerging as the most informative features. These results suggest that EEG gamma oscillations are reliable across recordings and can be used as a clinical biomarker as well as a potential tool for subject identification.Significance statementWe demonstrate the reliability of stimulus-induced gamma oscillations in elderly humans for the first time in EEG. Since gamma has recently been shown to be compromised in patients with Mild Cognitive Impairment or early Alzheimer’s Disease (AD), together these results mark the first steps towards an EEG based clinical biomarker for early diagnosis of AD. We observed high reliability in the power spectrum, gamma power and its temporal characteristics, within the test-retest period of one year. Alpha and steady-state-visually-evoked potential power were also found to be reliable. These spectral and temporal features could also be used to identify EEG recordings as belonging to the same versus different subjects with high performance, suggesting a potentially key role in subject identification also.

Recent studies have shown the existence of two gamma rhythms in the hippocampus subserving different functions but, to date, primate studies in primary visual cortex have reported a single gamma rhythm. Here, we show that large visual stimuli induce a slow gamma (25–45 Hz) in area V1 of two awake adult female bonnet monkeys and in the EEG of 15 human subjects (7 males and 8 females), in addition to the traditionally known fast gamma (45–70 Hz). The two rhythms had different tuning characteristics for stimulus orientation, contrast, drift speed, and size. Further, fast gamma had short latency, strongly entrained spikes and was coherent over short distances, reflecting short-range processing, whereas slow gamma appeared to reflect long-range processing. Together, two gamma rhythms can potentially provide better coding or communication mechanisms and a more comprehensive biomarker for diagnosis of mental disorders.SIGNIFICANCE STATEMENTGamma rhythm has been associated with high-level cognitive functions such as attention and feature binding and has been reported to be abnormal in brain disorders such as autism and schizophrenia. Unlike previous studies that have shown a single gamma rhythm in the primate visual cortex, we found that large visual gratings induce two distinct gamma oscillations in both monkey LFP and human EEG. These rhythms, termed slow (25–45 Hz) and fast (45–70 Hz), exhibited distinct tuning preferences, latencies, and coherence profiles, potentially reflecting processing at two different ranges. Multiple gamma oscillations in visual cortex may provide a richer representation of external visual stimuli and could be used for developing brain–machine interfacing applications and screening tests for neuropsychiatric disorders.

Background: Global Youth Tobacco Survey (GYTS) represented that the prevalence of tobacco by adolescents was around 19% in Gujarat. It shows the alarming statistics of tobacco use by adolescents. Objective: (1) To study the sociodemographic profile of students (from fifth to eighth standards), (2) to assess the knowledge, attitude, and practices regarding tobacco consumption among them, (3) to study the prevalence of tobacco consumption among them, (4) to study the association between tobacco consumption and other variables and (5)to impart them health education regarding the hazards of tobacco. Materials and Methods: A cross-sectional study was done by multistage sampling method from February 2013 to December 2014 after obtaining ethical consideration from the district education officer (DEO) and principals of the schools. According to the 14.6% prevalence of GYTS, the sample size was calculated, and 2,842 students from fifth to eighth standards from 18 schools of six zones of Ahmedabad were enrolled and studied using a predesigned, pretested, structured questionnaire. Health education session was organized by using audiovisual aids regarding the harmful effects of tobacco. The study was conducted, and data were analyzed by using appropriate statistical software. Result: Of the 2,842 students, 69.1% of them were aware that tobacco is hazardous to health and 26.3% students knew that passive smoking is harmful. One-fourth of them were aware about antitobacco messages. Regarding attitude, more than one-third of the students believed that tobacco consumption makes one smart and helps in making a number of friends. If tobacco was offered free of cost, 14.5% were ready to use. Regarding their practices, the prevalence of tobacco use was 12.2%. The mean age of initiation was 11.66 ± 1.89 years. The mean number of pouches consumed per week was 1.8 ± 1.65. About 35% students attempted to quit tobacco in the last 1 year and 47% were unable to quit. Conclusion: Tobacco use is an important risk behavior among adolescents. Peer pressure was the most predominant risk factor for tobacco consumption.

Reproductive factors are not considered to play a significant role in the aetiology of breast cancer in low incidence regions like Gujarat, although it is well established that they exert a major influence on such tumours in the western developed world. Women in the western Indian region have a very low prevalence of smoking, alcohol consumption but a high prevalence of vegetarianism. Noting the changes in the life style practices with increasing affluence is likely to yield several interesting findings in such a population. Physical activity and dietary factors have emerged as important parameters and their lack may contribute significantly to the risk of breast cancers. The breast cancer risk significantly increased with higher consumption of total fat (25% of total calories), frequent intake of fried foods and sweets. A significant protection was offered by frequent consumption of green yellow leafy vegetables, foods rich in b-carotene and isoflavonoids. The present study demonstrated a good protective effect of dietary intake of antioxidant vitamins. The breast cancer risk increases with elevation of circulating lipid components except HDL-cholesterol.

Background: Rabies is a zoonotic disease, which is caused by animal bites. Dog bites are responsible for 99% of rabies cases. Postexposure prophylaxis with anti-rabies vaccine is the only way to prevent rabies infection. Aims and Objectives: To analyze the magnitude of animal bite and actual practices following such bites, and to evaluate the quality of care delivered to the victim of animal bite in community health centers (CHCs). Materials and Methods: A hospital-based cross-sectional study was carried out in Rural Health Training Center of NHL Municipal Medical College (Singarva CHC), Ahmedabad, Gujarat, India. Total 580 animal bite cases were interviewed with pretested questionnaire during November 2012 to January 2013. Results: In our study, median age of the study population was 22 years; 4% of patients were below 5 years of age. Majority of bites were due to dogs (98%) followed by monkeys (1%) and cats (1%). Bites in male subjects were 76%. Class II bites constituted 91%. Most common site of bites was legs (61%) followed by hands (16%) and thighs (10%). Timing of the bites showed that 42% bites occurred in the evening, about 33% in the morning, and 23% in the afternoon. Majority of cases (60.3%) were reported within 24 h after bite and 2% cases after 5 days. Total 72% patients have missed one or more doses. Among them, default for second dose was 19% followed by 21% for third dose. Fourth and fifth doses were missed by 26% and 34% patients, respectively. 27%, 31%, 24%, and 17% delayed dose were found in second, third, fourth, and fifth doses, respectively. Conclusion: Majority of patients believed that anti-rabies vaccine is not given on Sunday, and it is the most common cause for

Real-time (RT) simulation is a highly reliable simulation method that is mostly based on electromagnetic transient simulation of complex systems comprising many domains. It is increasingly used in power and energy systems for both academic research and industrial applications. Due to the evolution of the computing power of RT simulators in recent years, new classes of applications and expanded fields of practice could now be addressed with RT simulation. This increase in computation power implies that models can be built more accurately and the whole simulation system gets closer to reality. This Task Force paper summarizes various applications of digital RT simulation technologies in the design, analysis, and testing of power and energy systems.

This task force paper summarizes the state-of-the-art real-time digital simulation concepts and technologies that are used for the analysis, design, and testing of the electric power system and its apparatus. This paper highlights the main building blocks of the real-time simulator, i.e., hardware, software, input-output systems, modeling, and solution techniques, interfacing capabilities to external hardware and various applications. It covers the most commonly used real-time digital simulators in both industry and academia. A comprehensive list of the real-time simulators is provided in a tabular review. The objective of this paper is to summarize salient features of various real-time simulators, so that the reader can benefit from understanding the relevant technologies and their applications, which will be presented in a separate paper.