Using skewness and the first-digit phenomenon to identify dynamical transitions in cardiac models

Disruptions in the normal rhythmic functioning of the heart, termed as arrhythmia, often result from qualitative changes in the excitation dynamics of the organ. The transitions between different types of arrhythmia are accompanied by alterations in the spatiotemporal pattern of electrical activity that can be measured by observing the time-intervals between successive excitations of different regions of the cardiac tissue. Using biophysically detailed models of cardiac activity we show that the distribution of these time-intervals exhibit a systematic change in their skewness during such dynamical transitions. Further, the leading digits of the normalized intervals appear to fit Benford's law better at these transition points. This raises the possibility of using these observations to design a clinical indicator for identifying changes in the nature of arrhythmia. More importantly, our results reveal an intriguing relation between the changing skewness of a distribution and its agreement with Benford's law, both of which have been independently proposed earlier as indicators of regime shift in dynamical systems.Comment: 11 pages, 6 figures; incorporating changes as in the published versio

Prevalence of HIV Infection in HIV Exposed Infants in Chennai

1. The prevalence of HIV infection among HIV exposed infants in Chennai is 4%. The prevalence was 0% among those babies on artificial feeds. The prevalence among breastfed infants was 6.7%. 2. The literacy rate of the mothers was 92% and all the 100 mothers were aware that they were HIV positive and there was a risk of mother to child transmission. 3. None of the babies born to mothers on ART was PCR positive even though the CD 4 count was 350 and not on ART. 4. Most of the mothers (n=88), were in HIV clinical stage 1 or 2 and all the 4 positive babies were from this group. All those in stage 3 or 4 and on ART had no PCR positive baby. The prevalence of infection among babies born to mothers on ART irrespective of CD 4 count and HIV stage was 0%. 5. 71% of spouses were HIV positive. 13 mothers whose spouses were negative acquired the infection from HIV positive first husband who had expired. 6. 98% of the deliveries were institutional and all the institutional deliveries were given Nevirapine prophylaxis. 7. We did not find bleeding per vaginum as a risk factor for virus transmission in our study. However, prolonged rupture of membrane > 4 hours is a risk factor in our study. 8. We found the mothers need more counselling regarding the choice of feeding during antenatal visits and at delivery. 40% of mothers chose for replacement feeds from day 1 and none of baby was PCR positive from this group but positivity in breastfeeding group may not be attributed to breastfeeding alone. We couldnot see any major difference in the nutritional status or incidence of diarrhoea and respiratory infections among breastfed babies and those on replacement feeds. CONCLUSION: 1. The prevalence of HIV infection among HIV exposed infants in Chennai is 4 % with single dose nevirapine prophylaxis to mother and baby. 2. Maternal CD 4 count 350 when they were not on ART. 3. PROM > 4 hours is a risk factor for MTCT of HIV. 4. Breastfeeding is a definite risk factor for MTCT. There was no significant difference in the nutritional status of babies on breastfeeds and replacement feeds

Growth Performance of the Monsoon River Prawn Macrobrachium malcolmsonii on Formulated Feeds with Combinations of Pulses and Cereals along with Groundnut Oilcake and Soya Meal

This study was conducted to categorize the growth performance of feeds formulated with combinations of pulses and cereals (horse gram and ragi, green gram and pearl millet, and cow gram and wheat) along with groundnut oilcake and soya meal on the post larvae (PL) of the monsoon river prawn, Macrobrachium malcolmsonii. This is to promote the inland aquaculture of this economically important species. Two types of feeds with different proportions of pulse and cereal (type-A: 25% pulse + 25% cereal; type-B: 40% pulse + 10% cereal) were prepared in each combination along with equal proportion of groundnut oil cake and soya meal (20% each). Tapioca flour (5%) and egg albumin (4%) were used as binding agents. Vitamin B-complex (1%) was also mixed. These feeds were fed to M. malcolmsonii PL for a period of 45 days. The efficacy of these feeds on growth performance and biochemical constituents were assessed. Commercially available standard Scampi feed was served as control. The overall influence of these feeds on growth, and concentrations of total protein, amino acid, carbohydrate and lipid of PL were found to be the best in scampi feed followed by the feed rich in pulse (type-B) and the feed with equal proportion of pulses and cereals (type-A). Among three combinations of pulses and cereals were tested, the feed formulated with cow gram and wheat showed the best overall performance, followed by green gram and pearl millet, and horse gram and ragi.  All the results were confirmed through paired sample t-test, DMRT, and two-way ANOVA. The survival rate was found to be better in formulated feeds fed PL when compared with control. It is assumed that the additive/ preservative added in the commercially available scampi feed may be the reason for the lower survival rate recorded. Moreover, the commercially available scampi feed is not always affordable to small farmers. Therefore, the farm made feeds with locally available commodities of pulses and cereals can be prepared and used in a sustainable manner for healthy promotion of Macrobrachium culture

Influence of combined probiotics Lactobacillus sporogenes and Bacillus subtilis on survival, growth, biochemical changes and energy utilization performance of Macrobrachium rosenbergii (De Man 1879) post larvae

A 90-day feeding experiment was studied to determine the influence of the bacterial combination Lactobacillus sporogenes and Bacillus subtilis (LS+BS) on survival, growth, biochemical constituents and energy utilization performance of the freshwater prawn Macrobrachium rosenbergii post larvae (PL). Experimental diets were the same, except for the variation in probiotic levels. The probiotics LS+BS (4:3) were used at 0%, 1%, 2%, 3% and 4% inclusion rates in the experimental diets. After the feeding trail, the growth parameters of the PLs, such as survival, weight gain, specific growth rate, feed conversion efficiency and protein efficiency rate were significantly (P<0.05) higher in 4% LS+BS incorporated diet as compared with control. The food conversion ratio was significantly (P<0.05) lower in 4% LS+BS incorporated diet. The biochemical composition of the total protein, amino acid, carbohydrate and lipid ash content were significantly (P<0.05) higher in 4% LS+BS incorporated diet. However, insignificant difference was recorded in moisture content between control and experimental groups. The energy utilization parameters, such as feeding rate, absorption rate, conversion rate and metabolic rate were significantly (P<0.05) higher in 4% LS+BS incorporated diet fed PL.  These results revealed the benefits of the incorporation of the probiotic (LS+BS) in aqua feed for M. rosenbergii PL.&nbsp

Efficacy of Cereals and Pulses as Feeds for the Post-larvae of the Freshwater Prawn Macrobrachium rosenbergii ï€

Two types of feeds were prepared using cereals (maize, bajra and Italian millet) and pulses (green gram, red gram and cow gram) respectively and fed to the post larvae of M. rosenbergii for a period of 60 days. The efficacy of these feeds on growth performance, biochemical constituents and energy utilization were assessed and compared with commercially available standard Scampi feed. Statistically insignificant differences were seen in weight gain, specific growth rate and conversion rate between control and experiments, and between experiments. However, significant differences (

Potential Energy Landscape of CO Adsorbates on NaCl(100) and Implications in Isomerization of Vibrationally Excited CO

Several full-dimensional potential energy surfaces (PESs) are reported for vibrating CO adsorbates at two coverages on a rigid NaCl(100) surface based on first principles calculations. These PESs reveal a rather flat energy landscape for physisorption of vibrationless CO on NaCl(100), evidenced by various C-down adsorption patterns within a small energy range. Agreement with available experimental results is satisfactory, although quantitative differences exist. These PESs are used to explore isomerization pathways between the C-down and higher energy O-down configurations, which reveal a significant isomerization barrier. As CO vibration is excited, however, the energy order of the two isomer changes, which helps to explain the experimental observed flipping of vibrationally excited CO adsorbates

DESIGN AND DEVELOPMENT OF ELECTRONIC SYSTEM FOR VALVE ACTUATING MECHANISM BY FUZZY LOGIC IN IC ENGINE

The electronics play an important role in modernization of engines. Presently in engine the electronic system are used for fuel ignition, radiator temperature sensing, speed sensing. We have a new idea of introducing electronic system for valve actuating mechanism. We are likely to replace cam shaft with speed sensors, microcontroller and electronic solenoid valves. Here we use the fuzzy logic which is a type of programming based on artificial intelligence. Generally in an IC engine the rotary motion of cam shaft is transmitted to the reduction gear then from there it is taken to the rocker arm and finally to the valves. Due to the presence of more mechanical parts we face friction between them which in turn reduces the efficiency of the engine. So if we use a electronically controlled valve we can increase the efficiency of the engine. There will be wastage of power in the engine as the valve mechanisms are efficient only at the specific stipulated condition. By using the microcontroller powered by fuzzy logic the mechanism can function efficiently for all different speeds. And also high temperature resistant electromagnets are attached end of cylinder and piston. The electromagnet placed in cylinder is triggered by means of alternative pulses. so the exerted force on a piston slightly increases. so the both operations are combined and controlled by means of microprocessors & microcontrollers as far increase the efficiency

In vitro antibacterial activity of some plant essential oils

BACKGROUND: To evaluate the antibacterial activity of 21 plant essential oils against six bacterial species. METHODS: The selected essential oils were screened against four gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus vulgaris) and two gram-positive bacteria Bacillus subtilis and Staphylococcus aureus at four different concentrations (1:1, 1:5, 1:10 and 1:20) using disc diffusion method. The MIC of the active essential oils were tested using two fold agar dilution method at concentrations ranging from 0.2 to 25.6 mg/ml. RESULTS: Out of 21 essential oils tested, 19 oils showed antibacterial activity against one or more strains. Cinnamon, clove, geranium, lemon, lime, orange and rosemary oils exhibited significant inhibitory effect. Cinnamon oil showed promising inhibitory activity even at low concentration, whereas aniseed, eucalyptus and camphor oils were least active against the tested bacteria. In general, B. subtilis was the most susceptible. On the other hand, K. pneumoniae exhibited low degree of sensitivity. CONCLUSION: Majority of the oils showed antibacterial activity against the tested strains. However Cinnamon, clove and lime oils were found to be inhibiting both gram-positive and gram-negative bacteria. Cinnamon oil can be a good source of antibacterial agents