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Electron Transfer Pathways in Cell
Get PDFAnalysis of the electron salvation process data indicates that the electron transfer between the electron donor and acceptor is hindered by the electron salvation process. It is proposed that the electron transfer in the cell environment must be assisted by intermediate messenger called the “transport protein”
A novel apparatus/protocol designed for optogenetic manipulation and recording of individual neurons during a motivation and working memory task in the rodent
Get PDFInnovative molecular tools allow neuroscientists to study neural circuitry associated with specific behaviors. Consequently, behavioral methods must be developed to interface with these new molecular tools in order for neuroscientists to identify the causal elements underlying behavior and decision-making processes. Here we present an apparatus and protocol for a novel Go/No-Go behavioral paradigm to study the brain attention and motivation/reward circuitry in awake, head-restrained rodents. This experimental setup allows: (1) Painless and stable restraint of the head and body; (2) Rapid acquisition to simple or complex operant tasks; (3) Repeated electrophysiological single and multiple unit recordings during ongoing behavior; (4) Pharmacological and viral manipulation of various brain regions via targeted guide cannula, and; (5) Optogenetic cell-type specific activation and silencing with simultaneous electrophysiological recording. In addition to the experimental advantages, the head-restraint system is relatively inexpensive and training parameters can be easily modulated to the specifications of the experimenter. The system runs on custom LabView software. In summary, our novel apparatus and protocol allows researchers to study and manipulate components of behavior, such as motivation, impulsivity, and reward-related working memory during an ongoing operant behavioral task without interference from non task-related behaviors. For more information on the custom apparatus, software or to collaborate please visit www.neuro-cloud.net/nature-precedings/dolzani
Vesicles and lamella: outcome of the changing formation path of a sodium N-lauroylsarcosinate hydrate/1-decanol/water system
Get PDFVesicles are closed bilayers that enclose a part of the continuous phase inside the core. In spherical shape, they attain the minimum free energy state. Conversely, lamella with maximum free energy remain in planer bilayer shape in the colloidal dispersion. Even with the same amphiphile concentration the colloidal structures depend on different parameters, many of these already addressed in different reports. However, the effect of mixing procedure as a formation path is unidentified. Here we reported water in 1-decanol and 1-decanol in water; these two different mixing procedures yield vesicles and lamella at the same point of the phase diagram of a sodium N-lauroylsarcosinate hydrate/1-decanol/water system. It was found that the favorable and unfavorable contact of water with the weak tertiary ammonium cation in amino-acid head-group plays the crucial role in this process. Moreover, this weak cationic property of this amphoteric surfactant can be exploited to carry DNA for gene therapy with a nontoxic system instead of cationic
The biological cost of consciousness
Get PDFSome philosophers maintain that consciousness as subjective experience has no biological function. However, conscious brain events seem very different from unconscious ones. The cortex and thalamus support the reportable qualitative contents of consciousness. Subcortical structures like the cerebellum do not. Likewise, attended sensory stimuli are typically reportable as conscious, while memories of those stimuli are not so reportable until they are specifically recalled. 

Reports of conscious experiences in normal humans always involve subjectivity and an implicit observing ego. Unconscious brain events are not reportable, even under optimal conditions of report. While there are claimed exceptions to these points, they are rare or poorly validated. 

Normal consciousness also implies high availability (rapid conscious access) of the questions routinely asked of neurological patients in the Mental Status Examination, such as common sense features of personal identity, time, place, and social context. Along with “current concerns,” recent conscious contents, and the like, these contents correspond to high frequency items in working memory. While working memory contents are not immediately conscious, they can be rapidly re-called to consciousness. 

The anatomy and physiology of reportable conscious sensorimotor contents are ultraconserved over perhaps 200 million years of mammalian evolution. By comparison, full-fledged language is thought to arise some 100,000 years ago in homo sapiens, while writing, which enables accel-erated cultural development, dates between 2.5 and 6 millennia. Contrary to some claims, therefore, conscious waking precedes language by hundreds of millions of years. 

Like other major adaptations, conscious and unconscious brain events have distinctive biological pros and cons. These involve information processing efficiency, metabolic costs and benefits, and behavioral pros and cons. The well known momentary limited capacity of conscious contents is an example of an information processing cost, while the very large and energy-hungry corticothalamic system makes costly metabolic demands. 

After a century of scientific neglect, fundamental concepts like “conscious,” “unconscious,” “voluntary” and “non-voluntary” are still vitally important, because they refer to major biopsychological phenomena that otherwise are difficult to discuss. 

Aluminium - Magnesium Silicate enhances antibacterial activity of Ampicillin trihydrate, against Salmonella gallinarum
Get PDFSolutions of different concentrations, of Ampicillin trihydrate (AT) and of a formulation of AT in Aluminium Magnesium Silicate (AMS), were used for sensitivity test on Salmonella gallinarum cultures. Also, S. gallinarum-infected chicks were treated with; 10 mg / Kg (AT), 10 mg / Kg (AT in AMS), 7.5 mg / Kg ( AT), 7.5 mg /Kg (AT in AMS). Mean inhibition area, 28.39 mm produced by AT did not vary significantly (P ) from 26.36 mm produced by AT in AMS. However, 17.5 105 Salmonella gallinarum culture forming units per ml of bile of the untreated chicks and 3.4 105 (80.58 % reduction), 2.5 105 (85.7 % reduction) , 5.4 105 (69.2 % reduction ) and 0.38 105 (97.8 % reduction ) of the respective treated groups, showed AMS significantly (P 0.01) improved AT`s ability to clear the infection, in vivo
A New Method for Characterization of Natural Zeolites and Organic Nanostructure using Atomic Force Microscopy
Get PDFIn order to study and develop an economic solution to environmental pollution in water, a wide variety of materials were investigated. Natural zeolites emerge from that research as the best in class of this category. Zeolites are natural materials relatively abundant and non biodegradable, economic and good to perform processes of environmental remediation. This paper contains a full description of a new method to characterize superficial properties of natural zeolites of exotic provenience (Caribbean Islets) with atomic force microscopy (AFM). AFM works with the optical microscope simplicity and the high resolution typical of a transmission electron microscope (TEM). Structural information of mesoporous material is obtained using scanning and transmission electron microscopy (SEM and TEM), only if the sample is conductive, otherwise the sample has to be processed through the grafitation technique, but this procedure induces errors of topography. Therefore, the existing AFM method, to observe zeolite powders, is made in a liquid cell-head scanner, but this work puts in evidence and confirms that it is possible to use an ambient air-head scanner to obtain a new kind of microtopography. Once optimized, this new method allows investigating of organic micelles, very soft nanostructure, of cetyltriammonium bromide (CTAB) upon an inorganic surface such as natural zeolites. It is shown some correlation between SEM microphotographies and AFM 3D images
Limits to the detection of early warning signals of population collapse
Get PDFBackground/Question/Methods

The recog­ni­tion that ecosys­tems can undergo sud­den shifts to alter­nate, less desir­able sta­ble states has led to the desire to iden­tify early warn­ing signs of these impend­ing col­lapses. This search has been moti­vated by the math­e­mat­ics of bifur­ca­tions, in which sud­den shifts result not from direct per­tur­ba­tions to the state (i.e. the pop­u­la­tion abun­dance, through mech­a­nisms such as over-harvesting) but to a slowly chang­ing para­me­ter that impacts the sys­tem sta­bil­ity. While these col­lapses can­not be antic­i­pated by observ­ing only the mean dynam­ics (as described by a deter­min­is­tic model), signs of the impend­ing col­lapse are expressed in the ran­dom per­tur­ba­tions, or noise, inher­ent in real sys­tems. The math­e­mat­i­cal the­ory of early warn­ing signs exploits this fact by seek­ing to detect pat­terns such as “crit­i­cal slow­ing down” of these per­tur­ba­tions due to the grad­ual loss of sta­bil­ity which leads to a bifurcation.

While much atten­tion has been given to empha­siz­ing the exis­tence both of sud­den col­lapses and of signs of crit­i­cal slow­ing down, lit­tle atten­tion has been paid to its detec­tion. Faced with only finite data, any method risks both false alarms and failed detec­tion events. We believe that weigh­ing these risks must be the bur­den of man­age­ment pol­icy, while research must first pro­vide a reli­able way to quan­tify the rel­a­tive risks of each. We present a method which quan­ti­fies this risk and show how to decrease the uncer­tainty inher­ent in com­mon summary-statistic approaches through the use of a like­li­hood based mod­el­ing approach.

Results/Conclusions

We demon­strate that com­monly used cor­re­la­tion tests applied to sum­mary sta­tis­tics such as auto­cor­re­la­tion and vari­ance are both inap­pro­pri­ate and insuf­fi­cient tests of early warn­ing signals.

Our method esti­mates directly the para­me­ters of a gen­er­al­ized model of the bifur­ca­tion pos­tu­lated by early warn­ing sig­nals the­ory, with and with­out the pres­ence of a grad­ual change lead­ing towards col­lapse. Using Monte Carlo sim­u­la­tion we gen­er­ate the dis­tri­b­u­tion of warning-signal sta­tis­tics expected under each model. From this we can quan­tify the risk of false alarms and missed detec­tion. We then show how apply­ing this approach to the data directly rather than the sum­mary sta­tis­tic increases the power of detec­tion. We illus­trate the approach in both sim­u­lated and empir­i­cal data of sud­den eco­log­i­cal shifts
In-group/out-group bias in contagious yawning
Get PDFBias for an in-group is a social phenomenon characterized by an affinity for one’s in-group over a perceived out-group. Activation in the amygdala, which is implicated in social and emotional processes, is increased when humans view other-race faces. This increase in activation is associated with implicit racial bias as indicated by scores on an implicit attitude test. Contagious yawning is a social process that appears to subserve empathic processes enabling the inferential modeling of the mental states of others and is exhibited in few species other than humans, including chimpanzees (Pan troglodytes), stumptail macaques (Macaca arctoides), dogs (Canis familiaris), and budgerigars (Melopsittacus undulatus). Despite these comparative data, little research has investigated intra-species variation in contagious yawning
Safety evaluation of Asparagus racemosus: a commonly used herb of Ayurvedic Medicine in Charles Foster rats
No full textAsparagus racemosus Willd., one of the most important medicinal plants, is regarded as a ‘rasayana’ in the Ayurvedic system of medicine and has been recommended for use as a galactagogue, aphrodisiac, anodyne, diuretic and nerve tonic since time immemorial, necessitating its incorporation into a number of important Ayurvedic formulations like Shatavarikalpa, Phalaghrita and Vishnutaila. However, data regarding safety or toxicity of Asparagus racemosus in animal systems is lacking. Hence, the present experiment envisaged acute and sub-acute toxicity of Asparagus racemosus root aqueous extract in adult Charles Foster rats following the guidelines of OECD including parameters like observational, hematological, biochemical and pathological studies. Except serum creatinine level in acute study and SGPT activity and serum creatinine level in sub-acute study, all the observational, hematological and biochemical parameters studied showed non-significant changes. Histopathological examination of hepatic sections of sub-acute samples showed mild inflammatory and fatty changes at higher doses
Ferric reducing antioxidant power and free radical scavenging activity of Moringa oleifera: Relevance in oxidative stress
Get PDFMoringa oleifera of family Moringaceae, commonly known as Horseradish-tree or the Ben-oil tree is an exceptionally nutritious vegetable tree with a variety of medicinal uses, distributed in tropical and subtropical regions of the world. The tree's bark, roots, fruit (pod), flowers, leaves, seeds and gum are used as an antiseptic, anticancer, anti-inflammatory, hepatoprotective and in treating rheumatism, venomous bites and other conditions. The immature green pods, called ‘drumsticks’ are probably the most valued and widely used part of the tree for water purification (e.g. desalination of ocean salt water). The leaves are highly nutritious, being a significant source of beta-carotene, vitamin C, protein, iron and potassium used in soups and sauces. The present study focuses on concentration-dependent ferric reducing antioxidant power (FRAP), free radical scavenging (DPPH), total phenolics (TP), total antioxidant capacity (TAC) and reducing power (RP) of moringa leaf and fruit (pod) extract compared with standard antioxidant. A strong positive co-relation was observed between FRAP, DPPH, TP and RP activity. Comparatively, the antioxidant potential of fruit extract was more pronounced than the leaf extract and ethanolic extract showed better activity than aqueous. On the basis of our observations, we hypothesize that moringa fruit (pod) and leaves can be a potential source of natural antioxidants due to their marked antioxidant activity