Neurocognitive basis of model-based decision making and its metacontrol in childhood.

Human behavior is supported by both goal-directed (model-based) and habitual (model-free) decision-making, each differing in its flexibility, accuracy, and computational cost. The arbitration between habitual and goal-directed systems is thought to be regulated by a process known as metacontrol. However, how these systems emerge and develop remains poorly understood. Recently, we found that while children between 5 and 11 years displayed robust signatures of model-based decision-making, which increased during this developmental period, there were substantial individual differences in the display of metacontrol. Here, we inspect the neurocognitive basis of model-based decision-making and metacontrol in childhood and focus this investigation on executive functions, fluid reasoning, and brain structure. A total of 69 participants between the ages of 6-13 completed a two-step decision-making task and an extensive behavioral test battery. A subset of 44 participants also completed a structural magnetic resonance imaging scan. We find that individual differences in metacontrol are specifically associated with performance on an inhibition task and individual differences in thickness of dorsolateral prefrontal, temporal, and superior-parietal cortices. These brain regions likely reflect the involvement of cognitive processes crucial to metacontrol, such as cognitive control and contextual processing.

Configuration spaces of hard spheres.

Hard sphere systems are often used to model simple fluids. The configuration spaces of hard spheres in a three-dimensional torus modulo various symmetry groups are comparatively simple and could provide valuable information about the nature of phase transitions. Specifically, the topological changes in the configuration space as a function of packing fraction have been conjectured to be related to the onset of first-order phase transitions. The critical configurations for 1 to 12 spheres are sampled using a Morse-theoretic approach, and they are available in an online, interactive database. Explicit triangulations are constructed for the configuration spaces of the two sphere system, and their topological and geometric properties are studied. The critical configurations are found to be associated with geometric changes to the configuration space that connect previously distant regions and reduce the configuration space diameter as measured by the commute time and diffusion distances. The number of such critical configurations around the packing fraction of the solid-liquid phase transition increases exponentially with the number of spheres, suggesting that the onset of the first-order phase transition in the thermodynamic limit is associated with a discontinuity in the configuration space diameter.

Use of the temporal extension of the buccal fat pad for closure of oro-antral communications.

Oro-antral communications/fistulae (OAC/OAF) can cause significant patient morbidity, with treatment for defects greater than 5mm in size requiring surgical reconstruction. This technical note evaluates the effectiveness, and proposes the use of, the temporal extension of the buccal fat pad (TEBFP) for the closure of large OAC. The TEBFP can be an effective means of large OAC closure due to its ease of harvesting, with minimal damage to surrounding structures or aesthetic changes. The use of the TEBFP provides stability, versatility, and tension-free closure, with minimal postoperative complications.

PredictSuperFam-PSS-3D1D: A server for predicting superfamily for the annotation of twilight zone protein sequences.

Annotation of twilight zone protein sequences has been hitherto attempted by predicting the fold of the given sequence. We report here the PredictSuperFam-PSS-3D1D method, which predicts the superfamily for a given twilight zone (TZ) protein sequence. Earlier, we have reported that adding predicted secondary structure information into the threading methods could improve fold prediction especially for the TZ protein sequences. In this study, we have analysed the application of the same method to predict superfamilies. Here, in this method, the twilight zone protein sequence is threaded with the 3D1D profiles of the known protein superfamilies library. In addition, weightage for the predicted secondary structure (PSS) is also employed. The performance of the method is benchmarked with twilight zone sequences. In the benchmarks, 62 and 65 percentages of superfamily predictions are obtained with GOR IV and NPS@ predicted secondary structures, respectively. Receiver Operating Characteristic (ROC) curves indicate that the method is sensitive in predicting the superfamilies. A case study has been conducted with the hypothetical protein sequences of Schistosoma haematobium (Blood Fluke) using this method and the results are analyzed. Our method predicts the superfamily for TZ sequences for which, methods based on sequence similarity alone are inadequate. A web server has been developed for our method and it is available online at http://bioinfo.bdu.ac.in/psfpss.

Magnesium Aluminate Nanoparticles for Chemical Detoxification of Sarin and Soman.

The solutions of Mg(NO3)2, Al(NO3)3, and (NH4)2CO3 were mixed at pH 8 and then heated at 95 °C for 4 h, aged at room temperature for 16 h, and calcined at 650 °C for 4 h to obtain magnesium aluminate nanoparticles. The obtained materials exhibited spinel structure with the particle size being 6 to 26 nm. The nanoparticles demonstrated type IV nitrogen adsorption isotherm, typical of mesoporosity with a surface area of 325 m²/g. They were utilized for studies on chemical detoxification of deadly chemical warfare agents such as sarin and soman. Our results showed that the magnesium aluminate nanoparticles effectively decontaminated more than 99% of sarin and soman within 8-10 min when used at a ratio of 1:50-60% w/w.

Effect of Deposition Potential and Bath Temperature on One-Step Electrochemical Synthesis of One and Two Dimensional Nanostructured ZnO Thin Films on Fluorine Doped Tin Oxide Substrates.

Different zinc oxide (ZnO) morphologies such as platelets, nanowalls and nanorods were electrochemically synthesized on fluorine doped tin oxide (FTO) substrates by varying the deposition potentials and bath temperatures, respectively. Cyclic voltammetry (CV) curves reveal that ZnO deposition potentials are decreased as the bath temperatures are increased. X-ray diffraction (XRD) patterns and transmission electron microscope (TEM) images confirm that the synthesized ZnO nanostructures are hexagonal wurtzite structure. The XRD results reveal that the crystallinity of the films is increased when ZnO deposition potentials and temperatures are increased. Field emission scanning electron microscope (FE-SEM) images display platelets, nanowalls and nanorods structures for films synthesized -1.1 V, -1.2 V and -1.3 V respectively. The increase in deposition potential not only increases the growth rate of ZnO with metallic zinc deposition, but also decreases zinc hydroxide chloride hydrate. Fourier transform infrared microscope (FTIR) spectra confirm that the formation of zinc hydroxide (Zn(OH)2) is decreased as the bath temperatures are increased from 30 to 70 °C. Photoluminescence (PL) spectra depict that the crystal quality of the ZnO films are notably improved as the bath temperatures are increased. The film thickness is increased as the deposition potentials and bath temperatures are increased. The dye absorbance is increased with respect to the film thickness. The efficiencies of dye sensitized solar cells (DSSCs) fabricated with diverse morphologies such as platelets, nanowalls and nanorods are found to be 0.10, 0.49 and 0.47%, respectively. Electrochemical impedance spectroscopy (EIS) spectra reveal that the charge transfer recombination resistance (Rrec) is continuously decreased as metal zinc deposition is increased in ZnO films with increase in deposition potentials.

Role of Annealing Temperatures on Mechanical, Optical, Electrical and Magnetic Properties of Nanohydroxyapatite Biomaterial.

Nanosized hydroxyapatite [Ca10(Po4)6(OH)2 or HAp] was prepared by applying wet-chemical precipitation technique. Thermogravimetric and Differential Scanning Calorimetry (TG/DSC) analyses, showed that the prepared sample was stable up to 919.2 °C. X-ray diffraction (XRD) pattern showed that as-prepared and annealed samples are in hexagonal structure. The average crystallite size is found to be 39, 46, 51 and 65 nm for the as-prepared, 700, 800 and 900 °C annealed HAp respectively. The dislocation density, strain and surface area were decreased with increase in annealing temperature. FT-IR and Raman spectra showed both as-prepared and annealed samples having characteristic bands of HAp. FE-SEM and TEM images which depicted and confirmed the hexagonal structure of HAp. The optical band gap calculated from the UV absorption behavior of as-prepared and annealed at 700, 800 and 900 °C HAp are 3.86, 3.84, 3.54, and 3.03 eV respectively. As the annealing temperature increases, the conductivity decreases whereas the impedance increases. The ac conductivity of as-prepared and annealed samples are in the order of 10-5 Sm-1. The VSM analysis confirmed that both as-prepared and annealed samples of HAp are in diamagnetic nature. The antibacterial activity of apatite samples depend on the types of bacterial strains and also their activity changed with the crystallite size.

Lingual frenotomy in neonates: past, present, and future.

During the last decade, increasing awareness of breastfeeding and its health benefits has not been reflected in the provision of lingual frenotomy in neonates with tongue-tie. This could be because of inconsistencies in our understanding of the importance and treatment of ankyloglossia. In this review, we discuss the current clinical guidance on diagnosis and management, and the future of such a service in the early postpartum period.

Improved Tet-On and Tet-Off systems for tetracycline-regulated expression of genes in Candida.

Tetracycline-regulated expression of genes is often used for functional analysis of Candida albicans genes. However, the widely used Tet-On system has certain limitations such as prolonged lag time (up to 8 h) for induction and non-uniform expression among the cells. We speculated that poor expression of tetracycline-controlled transactivator (Tet-transactivator) from CaADH1 promoter could be responsible for this, and thus compared the effect of expressing this protein under the control of CaADH1, CaTDH3 and CaRP10 promoters on the expression of GFP from the TET promoter. Only CaRP10 promoter facilitated a more uniform and rapid induction of GFP. However, a high concentration of doxycycline was needed for induction, which is not desirable for assessing certain phenotypes. Tet-Off systems are known to require a low concentration of doxycycline, but a limitation of the widely used Tet-Off system for C. albicans is the use of CaENO1 promoter, which is known to be repressed in the presence of gluconeogenic carbon source, for expression of transactivator. Thus, we have converted the above-mentioned Tet-On systems to Tet-Off systems by site-directed mutagenesis of the Tet-transactivator. Compared to the Tet-On systems, the Tet-Off systems required about 200-fold less concentration of doxycycline for modulation of gene expression. Only the Tet-Off system with CaRP10 promoter driving the expression of transactivator allowed rapid and high level expression of GFP compared to those with CaADH1 or CaTDH3 promoters. The utility of CaRP10 based Tet-On and Tet-Off systems was further validated by the conditional expression of the CaTUP1 gene. We have also adapted these systems for use with Candida tropicalis and find that the Tet-Off system is functional in this species. The Tet systems reported here will be useful for conditional expression of genes in C. albicans as well as C. tropicalis.

Complete genome sequence and comparative genomics of the probiotic yeast Saccharomyces boulardii.

The probiotic yeast, Saccharomyces boulardii (Sb) is known to be effective against many gastrointestinal disorders and antibiotic-associated diarrhea. To understand molecular basis of probiotic-properties ascribed to Sb we determined the complete genomes of two strains of Sb i.e. Biocodex and unique28 and the draft genomes for three other Sb strains that are marketed as probiotics in India. We compared these genomes with 145 strains of S. cerevisiae (Sc) to understand genome-level similarities and differences between these yeasts. A distinctive feature of Sb from other Sc is absence of Ty elements Ty1, Ty3, Ty4 and associated LTR. However, we could identify complete Ty2 and Ty5 elements in Sb. The genes for hexose transporters HXT11 and HXT9, and asparagine-utilization are absent in all Sb strains. We find differences in repeat periods and copy numbers of repeats in flocculin genes that are likely related to the differential adhesion of Sb as compared to Sc. Core-proteome based taxonomy places Sb strains along with wine strains of Sc. We find the introgression of five genes from Z. bailii into the chromosome IV of Sb and wine strains of Sc. Intriguingly, genes involved in conferring known probiotic properties to Sb are conserved in most Sc strains.

Critical role for CaFEN1 and CaFEN12 of Candida albicans in cell wall integrity and biofilm formation.

Sphingolipids are involved in several cellular functions, including maintenance of cell wall integrity. To gain insight into the role of individual genes of sphingolipid biosynthetic pathway, we have screened Saccharomyces cerevisiae strains deleted in these genes for sensitivity to cell wall perturbing agents calcofluor white and congo red. Only deletants of FEN1 and SUR4 genes were found to be sensitive to both these agents. Candida albicans strains deleted in their orthologs, CaFEN1 and CaFEN12, respectively, also showed comparable phenotypes, and a strain deleted for both these genes was extremely sensitive to cell wall perturbing agents. Deletion of these genes was reported earlier to sensitise cells to amphotericin B (AmB), which is a polyene drug that kills the cells mainly by binding and sequestering ergosterol from the plasma membrane. Here we show that their AmB sensitivity is likely due to their cell wall defect. Further, we show that double deletant of C. albicans is defective in hyphae formation as well as biofilm development. Together this study reveals that deletion of FEN1 and SUR4 orthologs of C. albicans leads to impaired cell wall integrity and biofilm formation, which in turn sensitise cells to AmB.

A comparative study on defect estimation using XPS and Raman spectroscopy in few layer nanographitic structures.

Defects in planar and vertically oriented nanographitic structures (NGSs) synthesized by plasma enhanced chemical vapor deposition (PECVD) have been investigated using Raman and X-ray photoelectron spectroscopy. While Raman spectra reveal the dominance of vacancy and boundary type defects respectively in vertical and planar NGSs, XPS provides additional information on vacancy related defect peaks in the C 1s spectrum, which originate from non-conjugated carbon atoms in the hexagonal lattice. Although an excellent correlation prevails between these two techniques, our results show that estimation of surface defects by XPS is more accurate than Raman analysis. Nuances of these techniques are discussed in the context of assessing defects in nanographitic structures.

Inhibitory Effect of Sophorolipid on Candida albicans Biofilm Formation and Hyphal Growth.

Candida albicans causes superficial and life-threatening systemic infections. These are difficult to treat often due to drug resistance, particularly because C. albicans biofilms are inherently resistant to most antifungals. Sophorolipid (SL), a glycolipid biosurfactant, has been shown to have antimicrobial and anticancer properties. In this study, we investigated the effect of SL on C. albicans biofilm formation and preformed biofilms. SL was found to inhibit C. albicans biofilm formation as well as reduce the viability of preformed biofilms. Moreover, SL, when used along with amphotericin B (AmB) or fluconazole (FLZ), was found to act synergistically against biofilm formation and preformed biofilms. Effect of SL on C. albicans biofilm formation was further visualized by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM), which revealed absence of hyphae, typical biofilm architecture and alteration in the morphology of biofilm cells. We also found that SL downregulates the expression of hypha specific genes HWP1, ALS1, ALS3, ECE1 and SAP4, which possibly explains the inhibitory effect of SL on hyphae and biofilm formation.

Prophylactic efficacy of S-2(2-aminoethylamino)ethyl phenyl sulfide (DRDE-07) against sulfur mustard induced lung toxicity in mice.

OBJECTIVE: The present study was planned to investigate the prophylactic efficacy of S-2(2-aminoethylamino)ethyl phenyl sulfide (DRDE-07), against topically applied SM induced pulmonary toxicity in mouse. MATERIALS AND METHODS: Animals were pretreated with S-2(2-aminoethylamino)ethyl phenyl sulfide (DRDE-07) (249.4 mg/kg by oral gavage) 30 minutes before SM exposure. The SM (6.48 mg/kg) was applied on hair clipped dorsocaudal region (percutaneous) of the animal. The animals were sacrificed on day 1, 3, 5 and 7. The biochemical changes those were observed in the bronchoalveolar lavage (BAL) fluid and lung tissue included protein, LDH, MPO, ß-glucuronidase, MMP-2, MMP-9, activated macrophages, reduced glutathione and lipid peroxidation level. RESULTS AND DISCUSSION: Pretreatment with DRDE-07 (0.2 LD50) attenuated SM-induced changes at all time point tested. BAL fluid biochemical endpoints indicated epithelial and endothelial cell damages as evidenced by increase in BAL protein, LDH level and increased number of activated macrophages. The increased myeloperoxidase activity and ß-glucuronidase level exhibited the degranulation of neutrophils due to SM toxicity in lung. The zymogrphy analysis of BAL fluid showed a significant increase in matrix metalloproteases (MMP) activity due to inflammatory cells accumulation. CONCLUSION: Thirty minutes pretreatment with DRDE-07 decreased vascular permeability reduced the inflammation and oxidative stress, hence may be recommended as a potential prophylactic agent for SM intoxication.

Control of Aedes aegypti and Ae. albopictus, the vectors of dengue and chikungunya, by using pheromone C21 with an insect growth regulator: Results of multicentric trials from 2007-12 in India.

BACKGROUND & OBJECTIVES: Aedes mosquito control has gained much importance nowadays in view of rise in number of reported cases of dengue and chikungunya in India and other countries. In the present study, C21 attracticide (containing a pheromone and an insect growth regulator­IGR, developed by Defence Research and Development Establishment (DRDE), Gwalior, India was tested for its feasibility for surveillance and control of Aedes mosquito in a multicentric mode from October 2007 to June 2012 in urban (Delhi, and Bengaluru district, Karnataka) and suburban (Alappuzha district, Kerala) settings of the country in three phases. METHODS: Across the randomly selected households in each study area, two to four containers treated with attracticide (experimental) and untreated (control) were placed and monitored by trained surveillance workers on weekly/ fortnightly basis for determining the presence of eggs, larvae and pupae. Container positivity, percent larvae, egg and pupae collected were determined during different phases and analyzed statistically using SPSS 18.0. RESULTS: Container positivity was found statistically significant at Bengaluru and Alappuzha, Kerala while in Delhi, it was found non-significant. Eggs collected from experimental containers were significantly higher in comparison to control at all the locations except Delhi. Also larvae collected from control containers were significantly higher at all the locations except Bengaluru. Pupae collected from control containers remained significantly higher at all the locations as no pupal formation was recorded from experimental containers. INTERPRETATION & CONCLUSION: The use of C21 attracticide hampered pupal formation, thus inhibiting adult population in the study areas. The study established that C21 attracticide was efficacious in the field conditions and has potential for use in surveillance and management of dengue and chikungunya mosquitoes.

An insight into the harmful effects of soy protein: A review.

Soy protein (SP) is a protein derived from soybean meal. SP is obtained from the removal of the outer shell of soybean and the fatty acid. The dietary supplementation of SP was was reported to have positive effects on human health. Therefore, the attention towards SP is increasing among the consumers, industrialist and researchers. However, the side effects and toxicity related to SP was not summarized, to date. This review summarized the toxic effects such as hormonal disturbances, carcinogenic and organotoxicity of SP based on the clinical and experimental studies. The review mainly focused on the effect of soy isoflavone-genistein on various organs. The main aim of the present review is to increase the public awareness on the harmful effect of SP on the various health aspects and draw the attention of the health care personnel and researchers.

Plasma Membrane Proteolipid 3 Protein Modulates Amphotericin B Resistance through Sphingolipid Biosynthetic Pathway.

Invasive opportunistic fungal infections of humans are common among those suffering from impaired immunity, and are difficult to treat resulting in high mortality. Amphotericin B (AmB) is one of the few antifungals available to treat such infections. The AmB resistance mechanisms reported so far mainly involve decrease in ergosterol content or alterations in cell wall. In contrast, depletion of sphingolipids sensitizes cells to AmB. Recently, overexpression of PMP3 gene, encoding plasma membrane proteolipid 3 protein, was shown to increase and its deletion to decrease, AmB resistance. Here we have explored the mechanistic basis of PMP3 effect on AmB resistance. It was found that ergosterol content and cell wall integrity are not related to modulation of AmB resistance by PMP3. A few prominent phenotypes of PMP3 delete strain, namely, defective actin polarity, impaired salt tolerance, and reduced rate of endocytosis are also not related to its AmB-sensitivity. However, PMP3 overexpression mediated increase in AmB resistance requires a functional sphingolipid pathway. Moreover, AmB sensitivity of strains deleted in PMP3 can be suppressed by the addition of phytosphingosine, a sphingolipid pathway intermediate, confirming the importance of this pathway in modulation of AmB resistance by PMP3.

Ultrananocrystalline diamond-CMOS device integration route for high acuity retinal prostheses.

High density electrodes are a new frontier for biomedical implants. Increasing the density and the number of electrodes used for the stimulation of retinal ganglion cells is one possible strategy for enhancing the quality of vision experienced by patients using retinal prostheses. The present work presents an integration strategy for a diamond based, high density, stimulating electrode array with a purpose built application specific integrated circuit (ASIC). The strategy is centered on flip-chip bonding of indium bumps to create high count and density vertical interconnects between the stimulator ASIC and an array of diamond neural stimulating electrodes. The use of polydimethylsiloxane (PDMS) housing prevents cross-contamination of the biocompatible diamond electrode with non-biocompatible materials, such as indium, used in the microfabrication process. Micro-imprint lithography allowed edge-to-edge micro-scale pattering of the indium bumps on non-coplanar substrates that have a form factor that can conform to body organs and thus are ideally suited for biomedical applications. Furthermore, micro-imprint lithography ensures the compatibility of lithography with the silicon ASIC and aluminum contact pads. Although this work focuses on 256 stimulating diamond electrode arrays with a pitch of 150 µm, the use of indium bump bonding technology and vertical interconnects facilitates implants with tens of thousands electrodes with a pitch as low as 10 µm, thus ensuring validity of the strategy for future high acuity retinal prostheses, and bionic implants in general.