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How the Discovery of Brain Correlates of Consciousness Supports Non-Reductive Physicalism
Get PDFIn this work I attempt to justify the claim that the discovery of statistically relevant brain correlates of consciousness supports Non-Reductive Physicalism. First I distinguish the main varieties of Reductive and Non-Reductive Physicalism, selecting the right one that is benefited by progress in brain sciences. Second, I discuss epistemological problems in the search of brain correlates of consciousness, focusing on the simultaneous occurrence of conscious activity, known by means of subjective report, and the corresponding brain activity, registered with the help of technology. Finally, I argue – using Salmon´s concept of Statistical Explanation - that statistics affords a distinction of causal (physical) from casual (illusory) correlations
Using causal models to distinguish between neurogenesis-dependent and -independent effects on behaviour
Get PDFThere has been a substantial amount of research on the relationship between hippocampal neurogenesis and behaviour over the past fifteen years, but the causal role that new neurons have on cognitive and affective behavioural tasks is still far from clear. This is partly due to the difficulty of manipulating levels of neurogenesis without inducing off-target effects, which might also influence behaviour. In addition, the analytical methods typically used do not directly test whether neurogenesis mediates the effect of an intervention on behaviour. Previous studies may have incorrectly attributed changes in behavioural performance to neurogenesis because the role of known (or unknown) neurogenesis-independent mechanisms were not formally taken into consideration during the analysis. Causal models can tease apart complex causal relationships and were used to demonstrate that the effect of exercise on pattern separation is via neurogenesis-independent mechanisms. Many studies in the neurogenesis literature would benefit from the use of statistical methods that can separate neurogenesis-dependent from neurogenesis-independent effects on behaviour
Theory of the Origin, Evolution, and Nature of Life
No full textLife is an inordinately complex unsolved puzzle. Despite significant theoretical progress, experimental anomalies, paradoxes, and enigmas have revealed paradigmatic limitations. Thus, the advancement of scientific understanding requires new models that resolve fundamental problems. Here, I present a theoretical framework that economically fits evidence accumulated from examinations of life. This theory is based upon a straightforward and non-mathematical core model and proposes unique yet empirically consistent explanations for major phenomena including, but not limited to quantum gravity, phase transitions of water, why living systems are predominantly CHNOPS (carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur), homochirality of sugars and amino acids, homeoviscous adaptation, the triplet code, and DNA mutations. The theoretical framework proves the unity of macrocosmic and microcosmic realms, validates predicted laws of nature, and solves the puzzle of the origin and evolution of cellular life in the universe
Mind over chatter: plastic up-regulation of the fMRI alertness network by EEG neurofeedback
Get PDFEEG neurofeedback (NFB) is a brain-computer interface (BCI) approach used to shape brain oscillations by means of real-time feedback from the electroencephalogram (EEG), which is known to reflect neural activity across cortical networks. Although NFB is being evaluated as a novel tool for treating brain disorders, evidence is scarce on the mechanism of its impact on brain function. In this study with 34 healthy participants, we examined whether, during the performance of an attentional auditory oddball task, the functional connectivity strength of distinct fMRI networks would be plastically altered after a 30-min NFB session of alpha-band reduction (n=17) versus a sham-feedback condition (n=17). Our results reveal that compared to sham, NFB induced a specific increase of functional connectivity within the alertness/salience network (dorsal anterior and mid cingulate), which was detectable 30 minutes after termination of training. Crucially, these effects were significantly correlated with reduced mind-wandering 'on-task' and were coupled to NFB-mediated resting state reductions in the alpha-band (8-12 Hz). No such relationships were evident for the sham condition. Although group default-mode network (DMN) connectivity was not significantly altered following NFB, we observed a positive association between modulations of resting alpha amplitude and precuneal connectivity, both correlating positively with frequency of mind-wandering. Our findings demonstrate a temporally direct, plastic impact of NFB on large-scale brain functional networks, and provide promising neurobehavioral evidence supporting its use as a noninvasive tool to modulate brain function in health and disease
Comments on “Assessing future risk: quantifying the effects of sea level rise on storm surge risk for the southern shores of Long Island, New York”
No full textTide gauge and satellite data indicate that the rate of sea level rise has not increased significantly in response to the last 3/4 century of CO2 emissions, so there is no reason to expect that it will do so in response to the next 3/4 century of CO2 emissions. The best prediction for sea level in the future is simply a linear projection of the history of sea level at the same location in the past. For Long Island, that is about 7-8 inches by 2080
Structural and Dynamic Studies of Amino Acids, Proteins and Nucleic Acids By Chemical-Hyperspectral Imaging, FT-IR/NIR, Vibro-Rotational Spectroscopy, Plasma, Microwave and Neutron Spectroscopy
Get PDFA detailed review of structural and dynamic studies of amino acids, proteins and nucleic acids by spectroscopic techniques: microwaves, near infrared, UV, X-rays and neutrons, including also EXAFS, chemical-hyperspectral imaging and fluorescence correlation spectroscopy and FLIM, FRAP imaging with references, instrumentation diagrams and application examples for several related areas
Critical nutritional stress among adult tribal populations of West Bengal and Orissa, India.
Get PDFThis paper deals with cross-sectional studies carried out during the period 2004-2007. It is based on eight data sets of tribals of Paschim Medinipur and Bankura Districts of West Bengal and Keonjhar District of Orissa. The tribes include Bhumijs, Kora Mudis, Lodhas, Santals, Bathudis and Savars. Height and weight were measured following standard techniques. The body mass index (BMI) was computed following standard equation. Nutritional status (chronic energy deficiency, CED) was evaluated using internationally accepted cut-off values of BMI. We followed the World Health Organization's classification (1995) of the public health problem of low BMI, based on adult populations worldwide. Our results show that, in general, among the tribes studied:
i)Both sexes had very low levels of BMI
ii)There existed high rates of CED indicating a critical nutritional condition 
iii)Women experienced greater nutritional stress
iv)The nutritional situation is similar in both West Bengal as well as Orissa.

Suppression of TNF-α induced NFκB activity by gallic acid and its semi-synthetic alkyl-gallates: Possible role in cancer chemoprevention
No full textNFκB, a transcription factor, regulates the expression of a number of genes involved in carcinogenesis. Thus, agents that can suppress NFκB activation have the potential to suppress carcinogenesis. In the present investigation, gallic acid was isolated from Alchornea glandulosa (Euphorbiaceae) and eight semi-synthetic alkyl gallates were prepared from the reaction of the corresponding alcohols with gallic acid at 80oC for 48 h in good yields (70-97%). All the compounds were evaluated against TNF-α-induced NFκB activation with stable transfected 293/NFκB-Luc human embryonic kidney cells. Treatment of cells with gallic acid and the gallate esters (20 µg/ml) significantly reduced TNF-α induced NFκB activation. With IC50 values in a range of 10 to 50 µM, gallic acid esters mediated inhibitory activity greater than that of gallic acid (IC50 76 µM). In addition to the inhibition of NFκB activation, gallic acid mediated a modest cytotoxic effect, but none of the gallate esters affected cell viability at the tested concentrations. Based on these encouraging intracellular responses, we suggest suppression of NFκB activation by gallate esters could play a chemopreventive role in carcinogenesis, and further investigations are warranted
Bioconversion of eugenol into food flavouring agent vanillin
Get PDFMicroorganisms have the ability to chemically modify a wide variety of organic compounds by a process referred to as biological or microbial transformation, or in general, bioconversion. The microbial cells and their catalytic machinery (enzymes) accept a wide array of complex molecules as substrates, yielding products with unparallel chiral (enantio-), positional (region-) and chemical (chemo-) selectivity through various biochemical reactions. The present study was formulated on the objective of the conversion of abundantly available phytomolecules eugenol into vanillin, a compound of industrial importance, using microorganisms Aspergillus flavus, Aspergillus niger and Pseudomonas aeruginosa. These microbes were found to be capable of converting eugenol to industrially important cost-effective products, vanillin (used as flavouring agent). The results were analyzed using thin layer and gas chromatographic techniques. Our results demonstrated that A. flavus, A. niger and P. aerouginosa were able to transform eugenol to vanillin. Our findings may provide a novel approach for the production of cost-effective vanillin using microorganisms
Grid Potential Analysis and Docking Studies on a Dataset of N-Arylsulfonyl-3-AcetylIndoles as Anti-HIV Agent
Get PDFA grid potential analysis employing the AutoGPA module in MOE2009.10 was performed on a dataset of 42 molecules of N-arylsulfonyl-3-acetylindoles as anti-HIV agent. The molecular docking simulations were also employed to position the inhibitors to their binding site to determine the most appropriate binding mode for different conformations of molecule. The uniqueness of AutoGPA module is that it automatically builds the 3D-QSAR model on the pharmacophore based molecular alignment. The best AutoGPA 3D-QSAR model obtained in the present study gives the cross-validated q2 value of 0.588 and r2pred value of 0.701 among the fifty six 3D-QSAR model developed. Furthermore, the steric and electrostatic contour maps for AutoGPA model along with the 3D structure of protein (binding residue of active site) inlaid were obtained to better understand the structural requirements against HIV and interaction between binding residues of protein and inhibitors. The study shows that hydrophobic and hydrogen bonding potential groups are favorable for optimization of parent nucleus for better activity