The prefrontal landscape: implications of functional architecture for understanding human mentation and the central executive

1996 ◽  
Vol 351 (1346) ◽  
pp. 1445-1453 ◽  
Keyword(s):  
Prefrontal Cortex ◽  
Semantic Processing ◽  
Central Executive ◽  
Functional Architecture ◽  
Domain Specific ◽  
Prefrontal Cortical ◽  
Long Term Storage ◽  
The One ◽  
Object Cognition

The functional architecture of prefrontal cortex is central to our understanding of human mentation and cognitive prowess. This region of the brain is often treated as an undifferentiated structure, on the one hand, or as a mosaic of psychological faculties, on the other. This paper focuses on the working memory processor as a specialization of prefrontal cortex and argues that the different areas within prefrontal cortex represent iterations of this function for different information domains, including spatial cognition, object cognition and additionally, in humans, semantic processing. According to this parallel processing architecture, the ‘central executive’ could be considered an emergent property of multiple domain-specific processors operating interactively. These processors are specializations of different prefrontal cortical areas, each interconnected both with the domain-relevant long-term storage sites in posterior regions of the cortex and with appropriate output pathways.

scholarly journals Efficient Cryopreservation of Populus tremula by In Vitro-Grown Axillary Buds and Genetic Stability of Recovered Plants

Plants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 77
Author(s):  
Elena O. Vidyagina ◽  
Nikolay N. Kharchenko ◽  
Konstantin A. Shestibratov
Keyword(s):  
Survival Rate ◽  
Axillary Buds ◽  
Long Term Storage ◽  
Average Survival ◽  
Transgenic Lines ◽  
Ssr Loci ◽  
One Step ◽  
The One

Axillary buds of in vitro microshoots were successfully frozen at –196 °C by the one-step freezing method using the protective vitrification solution 2 (PVS2). Microshoots were taken from 11 transgenic lines and three wild type lines. Influence of different explant pretreatments were analyzed from the point of their influence towards recovery after cryopreservation. It was found out that the use of axillary buds as explants after removal of the apical one increases recovery on average by 8%. The cultivation on growth medium of higher density insignificantly raises the regenerants survival rate. Pretreatment of the osmotic fluid (OF) shows the greatest influence on the survival rate. It leads to the increase in survival rate by 20%. The cryopreservation technology providing regenerants average survival rate of 83% was developed. It was based on the experimental results obtained with explant pretreatment. Incubation time in liquid nitrogen did not affect the explants survival rate after thawing. After six months cryostorage of samples their genetic variability was analyzed. Six variable simple sequence repeat (SSR) loci were used to analyze genotype variability after the freezing-thawing procedure. The microsatellite analysis showed the genetic status identity of plants after cryopreservation and of the original genotypes. The presence of the recombinant gene in the transgenic lines after cryostorage were confirmed so as the interclonal variation in the growth rate under greenhouse conditions. The developed technique is recommended for long-term storage of various breeding and genetically modified lines of aspen plants, as it provides a high percentage of explants survival with no changes in genotype.

scholarly journals Prefrontal Cortical Response to Conflict during Semantic and Phonological Tasks

2007 ◽  
Vol 19 (5) ◽  
pp. 761-775 ◽  
Author(s):  
Hannah R. Snyder ◽  
Keith Feigenson ◽  
Sharon L. Thompson-Schill
Keyword(s):  
Prefrontal Cortex ◽  
Cognitive Control ◽  
Phonological Processing ◽  
Functional Organization ◽  
Inferior Frontal Gyrus ◽  
General Function ◽  
Left Inferior Frontal Gyrus ◽  
Domain Specific ◽  
Prefrontal Cortical ◽  
Specific Effects

Debates about the function of the prefrontal cortex are as old as the field of neuropsychology—often dated to Paul Broca's seminal work. Theories of the functional organization of the prefrontal cortex can be roughly divided into those that describe organization by process and those that describe organization by material. Recent studies of the function of the posterior, left inferior frontal gyrus (pLIFG) have yielded two quite different interpretations: One hypothesis holds that the pLIFG plays a domain-specific role in phonological processing, whereas another hypothesis describes a more general function of the pLIFG in cognitive control. In the current study, we distinguish effects of increasing cognitive control demands from effects of phonological processing. The results support the hypothesized role for the pLIFG in cognitive control, and more task-specific roles for posterior areas in phonology and semantics. Thus, these results suggest an alternative explanation of previously reported phonology-specific effects in the pLIFG.

Development of Equipment that Uses Far-Red Light to Impose Seed Dormancy in Arabidopsis for Spaceflight

2020 ◽  
Vol 4 (2) ◽  
pp. 8-19
Author(s):  
Caleb P. Fitzgerald ◽  
Richard J. Barker ◽  
Won-Gyu Choi ◽  
Sarah J. Swanson ◽  
Shawn D. Stephens ◽  
...  
Keyword(s):  
Life Support ◽  
Red Light ◽  
Aluminum Foil ◽  
Long Term Storage ◽  
Human Habitation ◽  
Petri Dishes ◽  
Bioregenerative Life Support System ◽  
The One ◽  
Bioregenerative Life Support

AbstractIn order to use plants as part of a bioregenerative life support system capable of sustaining long-term human habitation in space, it is critical to understand how plants adapt to the stresses associated with extended growth in spaceflight. Optimally, dormant seeds would be germinated on orbit to divorce the effects of spaceflight from the one-time stresses of launch. At an operational level, it is also important to develop experiment protocols that are flexible in timing so they can adapt to crew schedules and unexpected flight-related delays. Arabidopsis thaliana is widely used for investigating the molecular responses of plants to spaceflight. Here we describe the development of a far-red light seed treatment device that suppresses germination of Arabidopsis seeds for periods of ≥12 weeks. Germination can then be induced when the seeds encounter red light, such as transfer to the illumination from on orbit plant growth hardware. This device allows for up to twelve 10×10 cm square Petri dishes containing seeds on nutrient gel to be irradiated simultaneously. The far-red device is contained within a light-proof fabric tent allowing the user to wrap the Petri dishes in aluminum foil in the dark, preventing room lights from reversing the far-red treatment. Long-term storage of the wrapped plates is accomplished using foil storage bags. The throughput of this device facilitates robust, high-replicate biological experiment design, while providing the long-term pre-experiment storage required for maximum mission flexibility.

Semantic Repetition Priming for Verbal and Pictorial Knowledge: A Functional MRI Study of Left Inferior Prefrontal Cortex

1997 ◽  
Vol 9 (6) ◽  
pp. 714-726 ◽  
Author(s):  
Anthony D. Wagner ◽  
John E. Desmond ◽  
Jonathan B. Demb ◽  
Gary H. Glover ◽  
John D. E. Gabrieli
Keyword(s):  
Prefrontal Cortex ◽  
Repetition Priming ◽  
Conceptual Knowledge ◽  
Word Processing ◽  
Semantic Processing ◽  
Semantic Analysis ◽  
Functional Neuroimaging ◽  
Cortical Activation ◽  
Prefrontal Cortical ◽  
Mri Study

Functional neuroimaging studies of single-word processing have demonstrated decreased activation in left inferior prefrontal cortex (LIPC) during repeated semantic processing relative to initial semantic processing. This item-specific memory effect occurs under implicit test instructions and represents word-toword semantic repetition priming. The present study examined the stimulus generality of LIPC function by measuring prefrontal cortical activation during repeated relative to initial semantic processing of words (word-to-word semantic repetition priming) and of pictures (picture-to-picture semantic repetition priming). For both words and pictures, LIPC activation decreased with repetition, suggesting that this area subserves semantic analysis of stimuli regardless of perceptual form. Decreased activation was greater in extent for words than for pictures. The LIPC area may act as a semantic executive system that mediates on-line retrieval of long-term conceptual knowledge necessary for guiding task performance.

scholarly journals Engineering of super bactericidal cotton using pyridinium/di-N-chloramine siloxane with intensified synergism

2021 ◽  
Author(s):  
Yong Chen ◽  
Yuyu Wang ◽  
Zhendong Wang ◽  
Qiang Zhang ◽  
Qiuxia Han
Keyword(s):  
Uv Resistance ◽  
Killing Rate ◽  
Long Term Storage ◽  
Silicone Coating ◽  
Chemical Inertness ◽  
Crucial Information ◽  
The One ◽  
Silane Monomer ◽  
Term Storage

Abstract Tuning the ratio of complementary biocidal groups in a composite unit is proved to be a tactic to better minimize their weaknesses to realize higher synergism. A silane monomer, 6-(pyridin-4-yl)-3-(3-(trimethoxysilyl)propyl)-1,3,5-triazinane-2,4-dione, with biocidal precursors of one pyridinium and two N-chloramine sites was synthesized, hydrolyzed and dehydrocondensed on cotton cellulose. Specially, isonicotinaldehyde was ammonolyzed with biuret to produce 6-(pyridin-4-yl)-1,3,5-triazinane-2,4-dione that subsequently reacted with (γ-chloropropyl)trimethoxysilane to synthesize the silane monomer through nucleophilic substitution. The modifier on cotton was quaternized and chlorinated to transform the one pyridine and two amide N−H structures in each unit of the silicone to pyridinium and N-chloramine counterparts. The cationic pyridinium increases the hydrophilicity of the unit and electrically draws anionic bacteria to its two adjacent highly fatal N-chloramine sites, achieving a faster contact-killing rate than not only monofunctionality but also basic synergistic integration of one cationic center and one N-chloramine. This phenomenon is therefore referred to as “intensified synergism” and provides crucial information for the design of more powerful biocides. The pyridinium/di-N-chloramine silicone coating exhibited extraordinary durability towards UV irradiation, washing cycles and long-term storage due to the good UV resistance and chemical inertness of pyridinium and silicone backbone.

scholarly journals The Medial Prefrontal Cortex and Fear Memory: Dynamics, Connectivity, and Engrams

2021 ◽  
Vol 22 (22) ◽  
pp. 12113
Author(s):  
Lucie Dixsaut ◽  
Johannes Gräff
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Memory Formation ◽  
Memory Storage ◽  
Long Term Memory ◽  
Brain Areas ◽  
Long Term Storage ◽  
And Storage

It is becoming increasingly apparent that long-term memory formation relies on a distributed network of brain areas. While the hippocampus has been at the center of attention for decades, it is now clear that other regions, in particular the medial prefrontal cortex (mPFC), are taking an active part as well. Recent evidence suggests that the mPFC—traditionally implicated in the long-term storage of memories—is already critical for the early phases of memory formation such as encoding. In this review, we summarize these findings, relate them to the functional importance of the mPFC connectivity, and discuss the role of the mPFC during memory consolidation with respect to the different theories of memory storage. Owing to its high functional connectivity to other brain areas subserving memory formation and storage, the mPFC emerges as a central hub across the lifetime of a memory, although much still remains to be discovered.

Preparation And elemental analysis of ancient fibers

1987 ◽  
Vol 45 ◽  
pp. 410-411
Author(s):  
Allen Angel ◽  
Kathryn A. Jakes
Keyword(s):  
Cross Sections ◽  
Physical Structure ◽  
Energy Dispersive ◽  
Archaeological Sites ◽  
X Ray ◽  
Long Term Storage ◽  
Backscattered Electron ◽  
Electron Imaging

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.

Radioimmunotherapy for treatment of acute myeloid leukaemia and myelodysplastic syndrome

2005 ◽  
Vol 44 (03) ◽  
pp. 107-117
Author(s):  
R. G. Meyer ◽  
W. Herr ◽  
A. Helisch ◽  
P. Bartenstein ◽  
I. Buchmann
Keyword(s):  
Acute Myeloid Leukaemia ◽  
Myeloid Leukaemia ◽  
Primary Tumour ◽  
The Other ◽  
Haematopoietic Stem Cell ◽  
Other Hand ◽  
Primary Reduction ◽  
The One ◽  
Acute Myeloid

SummaryThe prognosis of patients with acute myeloid leukaemia (AML) has improved considerably by introduction of aggressive consolidation chemotherapy and haematopoietic stem cell transplantation (SCT). Nevertheless, only 20-30% of patients with AML achieve long-term diseasefree survival after SCT. The most common cause of treatment failure is relapse. Additionally, mortality rates are significantly increased by therapy-related causes such as toxicity of chemotherapy and complications of SCT. Including radioimmunotherapies in the treatment of AML and myelodyplastic syndrome (MDS) allows for the achievement of a pronounced antileukaemic effect for the reduction of relapse rates on the one hand. On the other hand, no increase of acute toxicity and later complications should be induced. These effects are important for the primary reduction of tumour cells as well as for the myeloablative conditioning before SCT.This paper provides a systematic and critical review of the currently used radionuclides and immunoconjugates for the treatment of AML and MDS and summarizes the literature on primary tumour cell reductive radioimmunotherapies on the one hand and conditioning radioimmunotherapies before SCT on the other hand.

Hidden “holes” in the capital of banks and the supply of credit to the real sector of economy

2018 ◽  
pp. 49-68 ◽  
Author(s):  
M. E. Mamonov
Keyword(s):  
Credit Risk ◽  
The Other ◽  
Real Sector ◽  
Capital Management ◽  
Loan Loss ◽  
Short Term ◽  
The Real ◽  
Ex Post ◽  
The One

Our analysis documents that the existence of hidden “holes” in the capital of not yet failed banks - while creating intertemporal pressure on the actual level of capital - leads to changing of maturity of loans supplied rather than to contracting of their volume. Long-term loans decrease, whereas short-term loans rise - and, what is most remarkably, by approximately the same amounts. Standardly, the higher the maturity of loans the higher the credit risk and, thus, the more loan loss reserves (LLP) banks are forced to create, increasing the pressure on capital. Banks that already hide “holes” in the capital, but have not yet faced with license withdrawal, must possess strong incentives to shorten the maturity of supplied loans. On the one hand, it raises the turnovers of LLP and facilitates the flexibility of capital management; on the other hand, it allows increasing the speed of shifting of attracted deposits to loans to related parties in domestic or foreign jurisdictions. This enlarges the potential size of ex post revealed “hole” in the capital and, therefore, allows us to assume that not every loan might be viewed as a good for the economy: excessive short-term and insufficient long-term loans can produce the source for future losses.

Modelling of Moisture Movement in Wood during Outdoor Storage

2001 ◽  
Vol 6 (2) ◽  
pp. 3-14 ◽  
Author(s):  
R. Baronas ◽  
F. Ivanauskas ◽  
I. Juodeikienė ◽  
A. Kajalavičius
Keyword(s):  
Experimental Data ◽  
Finite Difference ◽  
Climatic Conditions ◽  
Two Dimensional ◽  
Moisture Movement ◽  
Finite Difference Technique ◽  
Long Term Storage ◽  
Space Formulation ◽  
Term Storage

A model of moisture movement in wood is presented in this paper in a two-dimensional-in-space formulation. The finite-difference technique has been used in order to obtain the solution of the problem. The model was applied to predict the moisture content in sawn boards from pine during long term storage under outdoor climatic conditions. The satisfactory agreement between the numerical solution and experimental data was obtained.

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