Efficient Active Learning for Image Classification and Segmentation using a Sample Selection and Conditional Generative Adversarial Network

Training robust deep learning (DL) systems for medical image classification or segmentation is challenging due to limited images covering different disease types and severity. We propose an active learning (AL) framework to select most informative samples and add to the training data. We use conditional generative adversarial networks (cGANs) to generate realistic chest xray images with different disease characteristics by conditioning its generation on a real image sample. Informative samples to add to the training set are identified using a Bayesian neural network. Experiments show our proposed AL framework is able to achieve state of the art performance by using about 35% of the full dataset, thus saving significant time and effort over conventional methods

Male migration and risky sexual behavior in rural India: is the place of origin critical for HIV prevention programs?

<p>Abstract</p> <p>Background</p> <p>Recent studies of male migrants in India indicate that those who are infected with HIV are spreading the epidemic from high risk populations in high prevalence areas to populations in low prevalence areas. In this context, migrant men are believed to initiate and have risky sexual behaviors in places of destination and not in places of origin. The paucity of information on men's risky sexual behaviors in places of origin limits the decision to initiate HIV prevention interventions among populations in high out-migration areas in India.</p> <p>Methods</p> <p>A cross-sectional behavioral survey was conducted among non-migrants, returned migrants (with a history of migration), and active (current) migrants in rural areas across two districts with high levels of male out-migration: Prakasam district in Andhra Pradesh and Azamgarh district in Uttar Pradesh. Surveys assessed participant demographics, migration status, migration history, and sexual behavior along the migration routes, place of initiation of sex. District-stratified regression models were used to understand the associations between migration and risky sexual behaviors (number of partners, condom use at last sex) and descriptive analyses of migrants' place of sexual initiation and continuation along migration routes.</p> <p>Results</p> <p>The average age at migration of our study sample was 19 years. Adjusted regression analyses revealed that active migrants were more likely to engage in sex with sex workers in the past 12 months (Prakasam: 15 percent vs. 8 percent; adjusted odds ratio (aOR)=2.1, 95% CI 1.2-3.4; Azamgarh: 19 percent vs.7 percent; aOR=4.0, 95% CI 2.4-6.6) as well as have multiple (3+) sex partners (Prakasam: 18 percent vs. 9 percent; aOR=2.0, 95% CI 1.3-3.2; Azamgarh: 28 percent vs. 21 percent; aOR=1.9, 95% CI 1.2-3.0) than non-migrants. Contrary to popular belief, a high proportion of active and returned migrants (almost 75 percent of those who had sex) initiated sex at the place of origin before migrating, which is equivalent to the proportion of non-migrants who engaged in sex with sex workers as well as with casual unpaid partners. Moreover, non-migrants were more likely than migrants to engage in unprotected sex.</p> <p>Conclusion</p> <p>Findings of this study document that returned migrants and active migrants have higher sexual risk behaviors than the non-migrants. Most migrants initiate non-marital sex in the place of origin and many continue these behaviors in places of destination. Migrants’ destination area behaviors are linked to sex with sex workers and they continue to practice such behaviors in the place of origin as well. Unprotected sex in places of destination with high HIV prevalence settings poses a risk of transmission from high risk population groups to migrants, and in turn to their married and other sexual partners in places of origin. These findings suggest the need for controlling the spread of HIV among both men and women resulting from unsafe sex in places of origin that have high vulnerability due to the frequent migratory nature of populations.</p

Evaluation of an IUL Flash & Go Automated Colony Counter

An IUL Flash & Go automated colony counter was used to enumerate E. coli (ATCC 700728) colonies and its performance was compared with manual counting on spiral plates. A total of 85 plates were analyzed. Linear regression analysis and the log differences between the manual and automated counts were determined. The results were analyzed to evaluate the reliability and accuracy of the colony counter.  A correlation coefficient of 0.969, a slope of 0.932 and intercept of 0.25 all indicate a strong, linear relationship. The mean log value difference between the manual and Flash & Go count methods was -0.035. Of the 85 plates counted, 95% of the plates were within 0.15 log10 difference between the manual and Flash & Go automated counts. These results demonstrate that the Flash & Go automated colony counter is an effective, accurate and time saving alternative to the standard method of manual counting.      

Experimental determination of the electrical resistivity of beef

&nbsp;A. K. Mahapatra, B. L. Jones, C. N. Nguyen, G. Kannan(Agricultural Research Station, Fort Valley State University, 1005 State University Drive, Fort Valley, GA 31030, USA)&nbsp;Abstract: Electrical resistivity properties of beef were investigated. &nbsp;The resistivity behavior under three frequencies of 1, 10 and 100-kHz, different temperatures (5, 10, 15, and 20℃), different length and cross-sectional areas (width: 7 cm, two depths: &nbsp;3 and 5 cm, and four lengths: 7, 11, 15, and 19 cm) were determined. &nbsp;The electrical series circuit was found to be adequate to measure the resistivity properties of beef. &nbsp;Samples with warmer temperatures offered much less resistance and the resistivity values obtained at temperatures 5℃ and below were not consistent. &nbsp;Increasing temperature had a significant effect on the resistivity values of beef (p&lt;0.05).&nbsp; Increase in frequency did not have any significant effect on the resistivity properties of beef (p&gt;0.05). &nbsp;It was observed that resistivity was higher across the myofiber axes than along the myofiber axes. &nbsp;However, there was no significant difference between the fiber directions in terms of resistivity (p&gt;0.05). &nbsp;The mean resistivity of beef at 20℃ for across the myofiber and along the myofiber directions was found to be 365.42 Ohms.cm and 346.67 Ohms.cm, respectively.Keywords: electrical resistivity, beef, anisotropy&nbsp;Citation: Mahapatra A. K., B. L. Jones, C. N. Nguyen, and G. Kannan. &nbsp;Experimental determination of the electrical resistivity of beef. &nbsp;Agric Eng Int: CIGR Journal, 2010, 12(3): 124-128.&nbsp;&nbsp

ENHANCEMENT OF BIOAVAILABILITY OF GLIPIZIDE USING SOLID DISPERSIONS WITH GUM AEGLE MARMELOS

Objective: The aim of the proposed study was formulation and in vitro/ vivo evolution   of solid dispersions of glipizide with gum Aegle marmelos. Methods: The phase solubility of glipizide in 0.1N HCl was investigated in the presence of different concentrations of gum Aegle marmelos. The solid dispersions (SDs) of glipizide with gum Aegle marmelos were formulated using solvent evaporation method at ratios of 1:1, 1:2, and 1:5 (glipizide: gum Aegle marmelos). Dissolution studies were conducted. The physicochemical characterization of the formulations was performed by using Fourier-transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Subsequently, bioavailability of pure glipizide, solid dispersion and marketed product was performed in rat. Results: Glipizide solubility increased as the concentration of gum Aegle marmelos in 0.1N HCl was raised. The solubility study indicates spontaneous drug solubilization, which is supported by negative values of Gibb's free energy (ΔGotr). Glipizide rate of dissolution was increased in SDs containing gum, and the rate increased as the concentration of gum in the SDs increases. After preparing SDs and physical mixtures with gum, the mean dissolution time (MDT) of glipizide decreases considerably. FTIR spectroscopy study revealed that stability and the absence of a well-defined glipizide-gum interaction. The amorphous condition of glipizide in SDs of glipizide with gum was revealed by DSC and XRD studies. Conclusion: The DSC and XRD studies indicate conversion of drug from crystalline to microcrystalline or amorphous form after formulation of solid dispersion with Aegle gum. The solid dispersion of glipizide with Aegle gum (893.04±25.5) showed better therapeutic activity compared to pure glipizide (535.65±11.5) and marketed formulation (767.5±13.6)

Oxidation mechanism in metal nanoclusters: Zn nanoclusters to ZnO hollow nanoclusters

Zn nanoclusters (NCs) are deposited by Low-energy cluster beam deposition technique. The mechanism of oxidation is studied by analysing their compositional and morphological evolution over a long span of time (three years) due to exposure to ambient atmosphere. It is concluded that the mechanism proceeds in two steps. In the first step, the shell of ZnO forms over Zn NCs rapidly up to certain limiting thickness: with in few days -- depending upon the size -- Zn NCs are converted to Zn-ZnO (core-shell), Zn-void-ZnO, or hollow ZnO type NCs. Bigger than ~15 nm become Zn-ZnO (core-shell) type: among them, NCs above ~25 nm could able to retain their initial geometrical shapes (namely triangular, hexagonal, rectangular and rhombohedral), but ~25 to 15 nm size NCs become irregular or distorted geometrical shapes. NCs between ~15 to 5 nm become Zn-void-ZnO type, and smaller than ~5 nm become ZnO hollow sphere type i.e. ZnO hollow NCs. In the second step, all Zn-void-ZnO and Zn-ZnO (core-shell) structures are converted to hollow ZnO NCs in a slow and gradual process, and the mechanism of conversion proceeds through expansion in size by incorporating ZnO monomers inside the shell. The observed oxidation behaviour of NCs is compared with theory of Cabrera - Mott on low-temperature oxidation of metal.Comment: 9 pages, 8 figure

N-(2-Amino-3,5-dibromo­benz­yl)-N-methyl­cyclo­hexan-1-aminium p-toluenesulfonate

The title compound, C14H21Br2N2 +·C7H7O3S−, features a salt of protonated bromhexine, a pharmaceutical used in the treatment of respiratory disorders, and the p-toluenesulfonate anion. The crystal packing is stabilized by inter­molecular N—H⋯O, N—H⋯Br and C—H⋯O hydrogen bonds

Inelastic effects in electron transport studied with wave packet propagation

A time-dependent approach is used to explore inelastic effects during electron transport through few-level systems. We study a tight-binding chain with one and two sites connected to vibrations. This simple but transparent model gives insight about inelastic effects, their meaning and the approximations currently used to treat them. Our time-dependent approach allows us to trace back the time sequence of vibrational excitation and electronic interference, the ibrationally introduced time delay and the electronic phase shift. We explore a full range of parameters going from weak to strong electron-vibration coupling, from tunneling to contact, from one-vibration description to the need of including all vibrations for a correct description of inelastic effects in transport. We explore the validity of single-site resonant models as well as its extension to more sites via molecular orbitals and the conditions under which multi-orbital, multi-vibrational descriptions cannot be simplified. We explain the physical meaning of the spectral features in the second derivative of the electron current with respect to the bias voltage. This permits us to nuance the meaning of the energy value of dips and peaks. Finally, we show that finite-band effects lead to electron back-scattering off the molecular vibrations in the regime of high-conductance, although the drop in conductance at the vibrational threshold is rather due to the rapid variation of the vibronic density of states.Comment: 38 pages, 14 figure

Assessment of Marine Weather forecasts over the Indian Sector of Southern Ocean

The Southern Ocean (SO) is one of the important regions where significant processes and feedbacks of the Earth\u27s climate take place. Expeditions to the SO provide useful data for improving global weather/climate simulations and understanding many processes. Some of the uncertainties in these weather/climate models arise during the first few days of simulation/forecast and do not grow much further. NCMRWF issued real-time five day weather forecasts of mean sea level pressure, surface winds, winds at 500 hPa & 850 hPa and rainfall, daily to NCAOR to provide guidance for their expedition to Indian sector of SO during the austral summer of 2014–2015. Evaluation of the skill of these forecasts indicates possible error growth in the atmospheric model at shorter time scales. The error growth is assessed using the model analysis/reanalysis, satellite data and observations made during the expedition. The observed variability of sub-seasonal rainfall associated with mid-latitude systems is seen to exhibit eastward propagations and are well reproduced in the model forecasts. All cyclonic disturbances including the sub-polar lows and tropical cyclones that occurred during this period were well captured in the model forecasts. Overall, this model performs reasonably well over the Indian sector of the SO in medium range time scale