Top PDF Topological reorganization of odor representations in the olfactory bulb.

Topological reorganization of odor representations in the olfactory bulb.

Topological reorganization of odor representations in the olfactory bulb.

The relationships between activity patterns across different populations of neurons provide initial insights into the mechanisms underlying pattern reorganization. During the early phase of an odor response, MC and IN activity patterns were topologically related to glomerular activity maps, suggesting that MC and IN activity patterns are initially driven to a large extent by glomerular input. The subsequent reorganization of activity patterns, however, implies that the chemotopic organization is unstable. This may be expected because inhibitory feedback from INs modifies MC activity, which in turn changes IN activity patterns. Because patterns of inhibitory feedback evoked by different stimuli are not identical, the pattern of inhibitory feedback onto MCs would modify OB output activity in an odor-specific manner. The reorganization of activity patterns is therefore likely to result, at least in part, from interactions between MCs and INs. After a few hundred milliseconds, OB output activity patterns stabilize [34], implying that feedback interactions between the populations of MCs and INs approach a dynamic equilibrium. An important mechanism contributing to the topological reorganization of MC activity patterns is the local sparsening of MC activity within initial foci. Foci in the MC layer were associated with dense IN activity in deeper layers, suggesting that local sparsening of MC activity patterns is caused by topologically related inhibitory feedback from INs. One prediction from this hypothesis is that the focality of IN activity should be lower than the initial focality of MC activity because connections from MCs to INs are divergent. This was indeed observed. A second prediction is that inhibitory feedback should reduce, but not completely abolish, the focality of MC activity patterns to maintain a dynamic equilibrium. Indeed, the focality of MC and IN activity patterns remained significantly different from that of randomized patterns (Figures 6A and 11A). A third predic- tion is that MC activity should not spread from the focus to adjacent regions because, unlike in the insect antennal lobe [67,77], extensive interglomerular excitatory interactions between principal neurons have not been described in the vertebrate OB (but see [78,79]). Consistent with this hypoth- esis, the density of activity outside foci was stable during the odor response (Figure 6C). Finally, the reduction of chemo- topy by topologically related inhibitory feedback and local sparsening could be reproduced in simulations (unpublished data). Hence, the topological reorganization of MC activity
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Olfactory dysfunction and neurotransmitter disturbance in olfactory bulb of transgenic mice expressing human A53T mutant α-synuclein.

Olfactory dysfunction and neurotransmitter disturbance in olfactory bulb of transgenic mice expressing human A53T mutant α-synuclein.

with special pathogen free (SPF) standards. Mice were maintained on a B6/C3H background. All animals were housed in their home cages and maintained on a reverse day/night cycle by artificially changing the light of the room. All tests were performed at the night cycle of animals in an undisturbed room. Standard rodent food and water were available ad libitum except spe- cific experiment period. Room temperature was maintained at 22±1°C, and relative humidity was set at 50±10%. At 1 month, the offspring were genotyped by semi-quantitative polymerase chain reaction (PCR) assay of DNA extracted from tails to discriminate tg mice from wt ones. Then these heterozygous tg mice were crossed to generate homozygous tg mice and quantita- tive PCR was used to differentiate homozygotes from heterozygotes. We selected male homo- zygous tg mice and wt littermates for our experiment. At 3 m old, 6 m old and 10 m old, tg (n = 30) and wt littermates (n = 30) were tested on olfactory function including social scent dis- crimination, non-social scent discrimination, odor memory and odor detection. A rater blind to genotype measured the sniffing time of each mouse and the latency to find the pellet. At 6 m old, wt (n = 12) and tg (n = 12) mice were sacrificed for cholinergic and DAergic staining (n = 3 per group), acetylcholine esterase (AchE) activity (n = 4 per group) and western blot (n = 5 per group) randomly. At 10 m old, wt (n = 13) and tg (n = 13) mice were sacrificed for cholinergic and DAergic staining (n = 4 per group), AchE activity (n = 4 per group) and west- ern blot (n = 5 per group) randomly. The data were analyzed by an observer who was blind to genotype.
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Involvement of cerebral nervous system areas and cytokines on  and anti inflammatory activities of kielmeyera rugosa choisy () in rodents

Involvement of cerebral nervous system areas and cytokines on and anti inflammatory activities of kielmeyera rugosa choisy () in rodents

The piriform cortex (PC) is a three-layered structure in which the principal excitatory neurons are pyramidal cells. One attractive feature of the piriform cortical slice preparation is that functionally distinct inputs from the olfactory bulb via the lateral olfactory tract. The infor- mation arriving through theses distal synapses provides the vast majority of olfactory signals to the cortex that is presumably used for sensory tasks such as odor discrimination and recognition (Suzuki and Bekkers, 2006; Bathellier et al., 2009). The PC, beyond of the olfactory function due to its connections with olfactory bulb, presents an influence on the aggressive and mating behavior, once this area receives information from the amygdala and hippocampus and projects their axons to amygdala and hypothalamus. These areas make connec- tion with the brain stem, including the raphe and parabrachial nuclei as well as the PAG, influencing the ascending and descending nociceptive circuits.
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Synaptic learning rules and sparse coding in a model sensory system.

Synaptic learning rules and sparse coding in a model sensory system.

and stores sensory information is a fundamental question in systems neuroscience. One challenge is to understand how neural oscillations, synchrony, population coding, and sparseness interact in the process of transforming and transferring information. Another question is how synaptic plasticity, the ability of synapses to change their strength, interacts efficiently with these different coding strategies to support learning and information storage. We ap- proached these questions, rarely accessible to direct experimental investigation, in the olfactory system of the locust, a well-studied example. Here, the neurons in the antennal lobe carry neural representations of odor identity using dense, spatially distributed, oscillatory synchronized patterns of neural activity. Odor information cannot be interpreted by considering their activity independently. On the contrary, in the mushroom body—the next processing region, involved in the storage and retrieval of olfactory memories and analogous to the olfactory cortex—odor representations are sparse and carried by more selective neurons. Sparse information coding by ensembles of neurons provides several important advantages including high memory capacity, low overlap between stored objects, and easy information retrieval. How is this sparseness achieved? Here, with a rigorous computational model of the olfactory system, we demonstrate that plasticity at the input afferents to the mushroom body can efficiently mediate the delicate tuning necessary to selectively filter intense sensory input, condensing it to the sparse responses observed in the mushroom body. Our results suggest a general mechanism for plasticity- enabled sparse representations in other sensory systems, such as the visual system. Overall, we illustrate a potential central role for plasticity in the transfer of information across different coding strategies within neural systems.
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Photoperiod mediated changes in olfactory bulb neurogenesis and olfactory behavior in male white-footed mice (Peromyscus leucopus).

Photoperiod mediated changes in olfactory bulb neurogenesis and olfactory behavior in male white-footed mice (Peromyscus leucopus).

Brain plasticity, in relation to new adult mammalian neurons generated in the subgranular zone of the hippocampus, has been well described. However, the functional outcome of new adult olfactory neurons born in the subventricular zone of the lateral ventricles is not clearly defined, as manipulating neurogenesis through various methods has given inconsistent and conflicting results in lab mice. Several small rodent species, including Peromyscus leucopus, display seasonal (photoperiodic) brain plasticity in brain volume, hippocampal function, and hippocampus-dependent behaviors; plasticity in the olfactory system of photoperiodic rodents remains largely uninvestigated. We exposed adult male P. leucopus to long day lengths (LD) and short day lengths (SD) for 10 to 15 weeks and then examined olfactory bulb cell proliferation and survival using the thymidine analog BrdU, olfactory bulb granule cell morphology using Golgi-Cox staining, and behavioral investigation of same-sex conspecific urine. SD mice did not differ from LD counterparts in granular cell morphology of the dendrites or in dendritic spine density. Although there were no differences due to photoperiod in habituation to water odor, SD mice rapidly habituated to male urine, whereas LD mice did not. In addition, short day induced changes in olfactory behavior were associated with increased neurogenesis in the caudal plexiform and granule cell layers of the olfactory bulb, an area known to preferentially respond to water-soluble odorants. Taken together, these data demonstrate that photoperiod, without altering olfactory bulb neuronal morphology, alters olfactory bulb neurogenesis and olfactory behavior in Peromyscus leucopus.
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Inducible and targeted deletion of the ERK5 MAP kinase in adult neurogenic regions impairs adult neurogenesis in the olfactory bulb and several forms of olfactory behavior.

Inducible and targeted deletion of the ERK5 MAP kinase in adult neurogenic regions impairs adult neurogenesis in the olfactory bulb and several forms of olfactory behavior.

We also examined the sensitivity of ERK5 icKO mice to farnesene, a synthetic, aggression-evoking pheromone [30,31]. ERK5 icKO mice were only able to detect farnesene at the highest concentration tested (500 mM) while control mice detected it at 100 mM (Fig. 6A; t-test, p = 0.009). Furthermore, mice were also examined for their detection of TMT, a component of fox scent that is known to elicit innate fear and alarm in rodents [24,32,33]. When mice detect TMT, they will typically avoid it and may Figure 3. ERK5 icKO mice have normal olfactory detection to discrete odorants in a habituation/dishabituation assay. Naı¨ve, adult mice were pre-trained with four presentations of mineral oil-soaked cotton swabs, then exposed to three structurally different odorants, citralva, isoamyl acetate (IAA), and ethyl vanillin with 4 trials per odorant. Step-wise decrease in the number of investigation during sequential presentations of the same odor followed by renewed interest in investigation of the first presentation of a new odorant suggests normal olfactory habituation/ dishabituation behavior. n $16 mice per treatment group from 2 independent experiments.
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Exposição a odores sociais: efeitos sobre a neurogênese adulta e a atividade neuronal de camundongos C57BL/6J machos

Exposição a odores sociais: efeitos sobre a neurogênese adulta e a atividade neuronal de camundongos C57BL/6J machos

Rodents, such as mice and rats, recognize conspecifics from social odors present in each individual’s urine. This ability is referred to as social memory or social recognition. It is established that social isolation leads to a social memory deficit in mice and that environmental enrichment by social odors – feces and urine from other mice placed in the cage bedding – prevents this deficit. Other forms of environmental enrichment lead to better performance in declarative memory tasks and increase adult neurogenesis in the Hippocampus and Olfactory Bulb of control mice. The new neurons that are born in the adult brain seem to have a crucial function in the establishment of new memories. Nevertheless, it has not been demonstrated whether the protective effect of environmental enrichment by social odors on social memory happens at the same time as an increase in the number of newborn neurons in the brain. Moreover, the brain structures activated during social memory processing are not fully described yet, and there is special doubt about whether the Hippocampus plays any important role in it. Thus, the main goal of this work was to access the effect of prolonged social odor presentation (environmental enrichment) on the adult neurogenesis of socially isolated mice and the effect of brief presentation of social odors (social encounter) on the neuronal activation pattern of control mice. In order to do that, we performed BrdU and NeuN immunofluorescence to quantify the number of new neurons born in the Hippocampus and Olfactory Bulb of one week socially isolated mice kept in an environment enriched by social odors and c-Fos immunohistochemistry to quantify the number of activated neurons in several brain regions of control mice presented to an unknown set of social stimuli (novel juvenile). The
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Reduced proliferation in the adult mouse subventricular zone increases survival of olfactory bulb interneurons.

Reduced proliferation in the adult mouse subventricular zone increases survival of olfactory bulb interneurons.

In the young adult, approximately 50% of adult-born cells that migrate into the OB differentiate to form interneurons that integrate into OB circuitry, while the other half undergo programmed cell death as progenitors, neuroblasts or young neuronal cells in the SVZ, RMS or OB [31,32,33]. At the molecular level, noradrenergic [34,35] and cholinergic transmis- sion [36,37,38], as well as cAMP response element binding protein (CREB) signaling, are thought to play important roles in regulating survival and death of adult-born cells residing in the OB. Disruption of CREB signaling reduces the survival of newborn neurons in the OB [39] and inhibits expression of the neurogenic transcription factor Pax 6 [40]. Pax 6 regulates the survival of mature OB DA neurons by controlling their expression of crystalline aA, which prevents apoptosis by inhibition of procaspase-3 activation [41]. At a more integrated level, survival of adult-born OB cells is associated with sensory experience [42]. Enriched odor exposure [43] and learning of olfactory discrim- ination [44] and associative [45] tasks are among the factors that promote survival, and this depends on the age of the cell and its location in the OB [46]. Sensory deprivation, on the other hand, decreases survival of new granule cells [47,48].
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Parallel odor processing by two anatomically distinct olfactory bulb target structures.

Parallel odor processing by two anatomically distinct olfactory bulb target structures.

The olfactory cortex encompasses several anatomically distinct regions each hypothesized to provide differential representation and processing of specific odors. Studies exploring whether or not the diversity of olfactory bulb input to olfactory cortices has functional meaning, however, are lacking. Here we tested whether two anatomically major olfactory cortical structures, the olfactory tubercle (OT) and piriform cortex (PCX), differ in their neural representation and processing dynamics of a small set of diverse odors by performing in vivo extracellular recordings from the OT and PCX of anesthetized mice. We found a wealth of similarities between structures, including odor-evoked response magnitudes, breadth of odor tuning, and odor-evoked firing latencies. In contrast, only few differences between structures were found, including spontaneous activity rates and odor signal-to-noise ratios. These results suggest that despite major anatomical differences in innervation by olfactory bulb mitral/tufted cells, the basic features of odor representation and processing, at least within this limited odor set, are similar within the OT and PCX. We predict that the olfactory code follows a distributed processing stream in transmitting behaviorally and perceptually-relevant information from low-level stations.
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Regulation of spike timing-dependent plasticity of olfactory inputs in mitral cells in the rat olfactory bulb.

Regulation of spike timing-dependent plasticity of olfactory inputs in mitral cells in the rat olfactory bulb.

In the developing olfactory bulb, the inhibitory synapses distributed along the secondary dendrites of the MCs can dynamically regulate the extent of spike propagation, with a smaller activation of the inhibitory synapses facilitating the spike propagation [48]. The lateral and recurrent inhibitions in the olfactory bulb play distinct roles in shaping the MC spiking pattern, which is critical to odor information processing [49]. Both the two forms of inhibition are thought to be important in odor Figure 8. Bidirectional regulation of STDP. (A) The effects of prior EPL stimulation on the subsequent LTP induction were reversed by the interleaved application of ISO (3.0 mM). The PS alone delivered to distal inputs at the EPL (EPL PSs) led to the enhancement of the LTP magnitude produced with a +30 ms pairing protocol (Dt = +30 ms). However, this protocol failed to facilitate LTP after the application of ISO during the STDP induction (EPL PSs+ISO; n = 6, compare with EPL PSs, p,0.01, compared with baseline, p.0.05). The arrow refers to the time-point of PS. (B) The effect of prior EPL stimulation on subsequent LTD induction was reversed by the interleaved application of ISO (3.0 mM; EPL PSs+ISO; n = 6, compare with EPL PSs, p,0.01, compared with control, p.0.05). The LTD was induced with a 250 ms pairing protocol (Dt = 250 ms). (C) An interleaved application of GBZ (1.5 mM) reversed the effect of the prior GCL stimulation on the subsequent LTP induction. Prior TBS alone delivered to proximal inputs at the GCL (GCL PSs) led to the suppression of the LTP magnitude produced with a +30 ms pairing protocol. An interleaved application of GBZ (1.5 mM; GCL PSs+GBZ) during STDP induction reversed the suppression of LTP by the GCL PSs (n = 6; P,0.01). (D) An interleaved application of GBZ (1.5 mM) reversed the effect of prior GCL stimulation on the subsequent LTD induction (n = 6, p,0.01). The control in A and C were the same as those in Fig. 3C, and the control in B and D were obtained from Fig. 3G. (E) Statistical plot showing that ISO (n = 6) or GBZ (n = 6) application could reverse the effects of EPL and GCL stimulation on the ISI to control the no-priming level (p,0.01).
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Odor memory stability after reinnervation of the olfactory bulb.

Odor memory stability after reinnervation of the olfactory bulb.

In this study, we administrated methimazole systemically to ablate the OSNs. Previous studies have demonstrated that methimazole is metabolized by a cytochrome P450 in sustentac- ular cells and Bowman glands, causing massive apoptosis and promoting the degeneration of OE supportive cells [6,51,52]. This leads to detachment of OSNs while progenitor cells remain intact [53]. Contrary to other methods, methimazole lesions induce minimal damage to the LP with no evident metaplasia of the OE [6]. The structure of the LP has an important role in axon navigation in the olfactory system. Axon bundles pack together and run through the LP and they grow and innervate the OB [54]. Recent studies demonstrate that sensory axons are presorted before they reach the OB. This early organization is crucial for correct targeting of glomeruli [55]. Therefore, after an extensive damage, the structural integrity of the LP is essential for navigation of new axons. Here, we report that 45 days after methimazole administration the major features of M72 and I7 glomerular Figure 4. No refinement of glomerular circuits after regeneration. A, The mean number of lateral glomeruli increased 45 days after methimazole administration (* denotes P,0.05). No evident refinement of glomeruli is observed 90 days after methimazole exposure (P.0.05). B, Percentage of hemibulbs showing the indicated number of glomeruli. C, Image of dorsal bulb from regenerated mice (left) and normalized plane with the distribution of miss routed axons at 45 (blue dots) and 90 (orange dots) days post lesion (right). D, Box plot of the number of miss routed axons. Mean 6 SEM are represented. Scale bar 200 mm, (ND, no difference).
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	Field Cancerisation of the Upper Aerodigestive Tract: Screening for Second Primary Cancers of the Oesophagus in Cancer Survivors

Field Cancerisation of the Upper Aerodigestive Tract: Screening for Second Primary Cancers of the Oesophagus in Cancer Survivors

Tobacco, alcohol, and betel quid are the main causes of squamous cell cancers of the upper aerodigestive tract. These substances can cause multifocal carcinogenesis leading to multiple synchronous or metachronous cancers of the oesophagus, head and neck region, and lungs (‘ield cancerisation’). Globally there are several million people who have survived either head and neck squamous cell cancer (HNSCC) or lung cancer (LC). HNSCC and LC survivors are at increased risk of developing second primary malignancies, including second primary cancers of the oesophagus. The risk of second primary oesophageal squamous cell cancer (OSCC) ranges from 8-30% in HNSCC patients. LC and HNSCC survivors should be ofered endoscopic surveillance of the oesophagus. Lugol chromoendoscopy is the traditional and best evaluated screening method to detect early squamous cell neoplasias of the oesophagus. More recently, narrow band imaging combined with magnifying endoscopy has been established as an alternative screening method in Asia. Low-dose chest computed tomography (CT) is the best evidence- based screening technique to detect (second primary) LC and to reduce LC-related mortality. Low-dose chest CT screening is therefore recommended in OSCC, HNSCC, and LC survivors. In addition, OSCC survivors should undergo periodic pharyngolaryngoscopy for early detection of second primary HNSCC. Secondary prevention aims at quitting smoking, betel quid chewing, and alcohol consumption. As ield cancerisation involves the oesophagus, the bronchi, and the head and neck region, the patients at risk are best surveilled and managed by an interdisciplinary team.
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The Existence Of Leading Islands Securing And The Border Areas Unitary State Of Indonesia An Analysis In Law Perspective

The Existence Of Leading Islands Securing And The Border Areas Unitary State Of Indonesia An Analysis In Law Perspective

Based on the objectives to be achieved and problems that have been formulated, the method used is juridical- sociological. The juridical approach is intended to explore and study the legislation as a basis for a research, while the sociological approach is intended to explore the factors and impacts incurred from the occurrence of border-area dispute and solution by the government. The specifications of this research are normative law called also as doctrinal research. A site was chosen by researcher to conduct a research is a government agency that includes the Navy (Department of Hydro-Oceanographic) related to the sea boundaries of the Republic of Indonesia and neighboring countries, local governments, especially in the leading islands border to the Republic of Indonesia related to culture, security, politics and thinking about the area/island they occupy, as a part of the Unitary of the Republic of Indonesia. The population is all research objects to be researched. In this research, the population is Navy and the relevant agencies involved in the security of sea area. The samples were chosen to be a material of research is the bearer of the security function in marine areas through the random system and interviews with relevant parties, such as Bakorkamla and community.
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An Analysis Of The Difference In Gender Level Of Cassava Production And Access To Land In Abia State Nigeria

An Analysis Of The Difference In Gender Level Of Cassava Production And Access To Land In Abia State Nigeria

Gupta (2000) views gender to refer to the widely shared expectations and norms within a society about appropriate male and female behavior, characteristics, and roles. It is a social and cultural construct that differentiates women from men and defines the ways in which women and men interact. Worthy to note that there has been some controversy on the social relationship between the two sexes that make up gender and this has raised a lot of dust and storm. Agriculture is the most assured engine of growth and development and reliable key to industrialization. Nigeria is the largest producer of cassava in the world (Ogbe et al, 2003). It is a very important staple food consumed in different forms by millions of Nigerians. Cassava roots are rich in energy, containing mainly starch and soluble carbohydrates, but are poor in protein. Cassava is once seen as the food for the poor but due to its value addition it is therefore a food for all. These and other features endowed it with a special capacity to bridge the gap in food security, poverty alleviation and environmental protection (Clair et.al, 2000). In many rural areas in Nigeria and several developing countries, women play a crucial role in providing and improving household food security (CTA, 2005).
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High-throughput analysis of promoter occupancy reveals new targets for Arx, a gene mutated in mental retardation and interneuronopathies.

High-throughput analysis of promoter occupancy reveals new targets for Arx, a gene mutated in mental retardation and interneuronopathies.

tract, have transcriptional repressor activity while the aristaless- related domain, located at the C-terminus, has transcriptional activator activity [19,20]. A few co-factors of Arx have been identified: the Groucho/transducin-like enhancer of split (TLE) family of co-repressors interacts with Arx octapeptide, whereas repression by the second domain occurs through the interaction with C-terminal binding proteins (CtBPs) [20]. In addition, Arx has four polyalanine tracts. The two ones located in the N- terminal part of Arx seem particularly important for the function of the protein as several expansions have been identified in patients. For this type of mutations, it has recently been suggested that the level of transcriptional repression activity may depend on the length of the alanine expansion [19]. Changes in the transcriptional activity of Arx may thus have subtle effects on neuronal function and contribute to the pathogenesis of ARX- related disorders, in particular intellectual deficiency and epilepsy. Although two gene expression profile analyses comparing E14.5 wild-type and Arx mutant ventral telencephalic tissues have recently been published in mouse, very few targets for this transcription factor have been described and only three (Lmo1, Ebf3 and Shox2) have been found to be direct [21,22]. Here, using chromatin immunoprecipitation in Arx-transfected neuroblastoma cells (N2a) or E15.5 mouse embryonic brain, followed by hybridization to mouse promoter arrays (ChIP-chip) [23], we identified new direct targets of Arx. We found a total of 1006 Arx- bound genes. A significant proportion of these promoters were enriched for a sequence very similar to a motif previously identified as Arx-binding motif. Both fixation and regulation of subsets of these targets have then been confirmed by ChIP-PCR and by the analysis of transcriptomic experiments performed from either Arx-overexpressing N2a cells or Arx knock-out mice.
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Developmental characterization of neuronal subpopulations involved in zebrafish visual processing

Developmental characterization of neuronal subpopulations involved in zebrafish visual processing

For each line and each developmental stage, the best representative samples are presented in the figures below as z-planes and z-maximum projections obtained from the original z-stacks (in Supplementary data). For the anatomical description of GFP expression (and TH expression when applicable), we follow a rostral to caudal order and separated structures from either the central (including the retina) or peripheral nervous system. The tentative assignment of the different structures is done by comparison of the original data with reference brains and gene and protein expression patterns reported in the literature and should be considered as an orientation for future work. Note that for the unknown anatomical structures, a name was created with the conjunction of the brain subdivision and a number given from rostral to caudal and dorsal to ventral (for ex. Rho1 – rhombencephalic cluster 1).
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Evaluation of susceptibility of the ZRE1 alloy to hot cracking in conditions of forced strain

Evaluation of susceptibility of the ZRE1 alloy to hot cracking in conditions of forced strain

This work in combination with industrial tests of casting welding show that the causes of high-temperature brittleness are the partial tears of the structure and the hot cracks of both the castings and the welded and padded joints. Such phenomena should be treated as irreversible failures caused by the process of crystallisation that is in the area of co-existence of the solid and liquid structural constituent. The assessment of the resistance to hot fractures was conducted on the basis of the transvarestriant trial. The transvarestriant trial consists in changing of strain during welding It was stated that the range of the high-temperature brittleness is very broad, which significantly limits the application of the welding techniques to join or mend the elements made of alloy ZRE-1. The brittleness is caused mainly by metallurgical factors, i.e., precipitation of inter-metal phases from the solid solution.
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The Impact of the Expansion of the Bolsa Familia Program on the Time Allocation of Youths And Their Parents Lia Chitolina Miguel Nathan Foguel Naercio Menezes-Filho

The Impact of the Expansion of the Bolsa Familia Program on the Time Allocation of Youths And Their Parents Lia Chitolina Miguel Nathan Foguel Naercio Menezes-Filho

Table 6 shows the results of estimating equation (3) to obtain the effect of the introduction of BVJ on school enrollment. It shows that the estimated effect of the interaction between treatment and time is positive and significant at the 5 per cent level, regardless of whether the control variables are included (column 1) or not (column 2). The estimated effects evinces that the expansion of the PBF for young people of 16 years of age increased the probability attending school by approximately 4 percentage points with respect to 15-year-olds. This result is noteworthy because, in addition to the immediate relief of poverty, one of the main purposes of the PBF is to reduce the transmission of poverty in the medium and long terms by increasing school enrollment among the poorest households. The results suggest that the expansion of the PBF to 16-year-olds has contributed to that goal.
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An Advancement To The Security Level Through Galois Field In The Existing Password Based Technique Of Hiding Classified Information In Images

An Advancement To The Security Level Through Galois Field In The Existing Password Based Technique Of Hiding Classified Information In Images

The Galois encoder generates the encrypted data that can be used for transmitting the Galois encrypted message. At the receiver 4 bit of encrypted data is decoded using the Galois decoder .Multiplier as private key & look up table at the Rx end is used for decryption of the original message signal. The same pseudo random algorithms used at the Galois transmitter side are used at the Galois receiver side to find the M and E, which are the pixels used for matching the data and embedding the 2BCs based on password. The location where the first bit of the 2BC is embedded in E can be obtained from the password. Then, depending on the technique used to embed the second bit of the 2BC, the second bit can be read directly, read from position 3, or read from different positions in a particular order according to techniques 1, 2and 3, respectively. The extracted bits are then combined to obtain the different 2BCs. The data bits are extracted from the M pixels based on the locations obtained from the 2BC‟s. When the location is „5‟, the receiver will check if the bits in locations 8, 7, 6 and 5 are the same. If they are the same, then this case corresponds to a “no match” and hence the complement of the bit in position 5 is taken as the data bit, else the same bit is
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Paced-mating increases the number of adult new born cells in the internal cellular (granular) layer of the accessory olfactory bulb.

Paced-mating increases the number of adult new born cells in the internal cellular (granular) layer of the accessory olfactory bulb.

The continuous addition of new cells during life has been found in several brain regions including: different cortical areas, the olfactory tubercles, anterior olfactory nuclei, tenia tecta, islands of Calleja, amygdala, caudate nucleus and nucleus accumbens [1,2,3,4]. However, the most studied regions that incorporate new neurons in adulthood are the hippocampus and the olfactory bulb (OB) [5,6]. In the hippocampus these new cells are born in the dentate gyrus and integrate into the granular layer. In the olfactory bulb this process has been extensively described in mice and consists of three stages: proliferation, migration and survival of the new cells. Proliferation begins in the subventricular zone (SVZ) located in the walls of the lateral ventricles, where most of the cells are generated. The process begins with the astrocyte-like stem B cells that give rise directly to neuroblast A cells that migrate tangentially along the rostral migratory stream (RMS), where a few cells can also be generated [7,8] to finally reach the OB [9,10]. Once in the OB they migrate radially to the granular and glomerular layers of the structure and integrate as mature interneurons [11,12,13,14].
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